Article

A quantitative technique for the identification of canopy stratification in tropical and temperate forests

March 2000
Forest Ecology and Management 127(1):77-86

March 2000
127(1):77-86

Authors:

University of Melbourne

Canopy stratification is one of the oldest concepts in tropical forest ecology. However, there has been considerable debate over the existence and identification of strata. Much of the confusion arises from the differing definitions of strata (i.e. vertical stratification of phytomass, individual crowns, or species) and the methods used to evaluate them (e.g. profile diagrams). In this paper, a quantitative technique for identifying stratification of individual tree crowns in the forest canopy is presented. Strata are identified by comparing sorted tree heights to a moving average of height at the base of the live crown. Height and crown measurements were obtained from 21 published profile diagrams of forests, representing many biogeographic regions and covering a wide variety of forest types. The technique provides an objective measure of canopy strata allowing for a valid comparison of stratification between the different profile diagrams. Neither the original author's estimates of strata nor the number of strata detected by the quantitative technique support the premise that tropical forests have more strata than temperate forests. With the sole exception of a mono-layered European Douglas-fir plantation, all forests in this study had two or three layers.

Automated characterization of forest canopy vertical layering for predicting forest inventory attributes by layer using airborne LiDAR data

Article

Full-text available

Jun 2023

Forest canopy vertical layering influences stand development and yield and is critical information for forest management planning and wood supply analysis. It is also relevant for other applications including habitat modelling, forest fuels management and assessing forest resilience. Forest inventories that use coincident airborne Light Detection and Ranging (LiDAR) data and field plots (i.e. area-based approach) to predict forest attributes generally do not consider the multi-layer canopy structure that may be found in many natural and managed forest stands. With airborne LiDAR, it is possible to separate single-layer and multi-layer stands. This information can be used to allocate predictions of forest attributes such as timber volume (m3 ha−1), by canopy layer. In this study, we used single-photon LiDAR data to automate the mapping of vertical stand layering in a temperate mixedwood forest with a variety of forest types and vertical complexities. We first predicted whether each 25 × 25 m grid cell had one or two canopy layers, and then partitioned inventory attributes (e.g. basal area (BA), gross total stem volume (GTV)) by canopy layer. We compared two methods for estimating attributes by layer at the stand level using nine independent validation stands. Overall agreement between the reference and predicted structure for the calibration plots was 74% (n = 266). At the grid-cell level, attributes were generally underestimated for the upper layer and overestimated for the lower layer. For the validation stands, the relative height of the lower layer was under-predicted compared to the reference data (46–52% versus 57%), while the proportion of BA and GTV in the lower layer were very similar to the reference values (17–19% versus 18% for BA and 12–15% versus 12% for GTV). Overall, the approach showed promise in distinguishing single- and two-layered stand conditions and partitioning estimates of inventory attributes such as BA and GTV by layer—both for grid cells and at the stand level. The inclusion of forest information by canopy layer enhances the utility of LiDAR-derived forest inventories for forest management in forest areas with complex, multi-layer stand conditions.

What is beneath the canopy? Structural complexity and understorey light intensity in Suserup Skov, eastern Denmark

Article

Full-text available

Jan 2007

A detailed understanding of the structural complexity and its effects on understorey light intensity in natural forests are important references for the further development of nature-based forest management. Based on a full inventory of a 1-ha plot in Suserup Skov, a near-natural temperate deciduous forest in Denmark, this research describes the structural complexity in three dimensions and identify structural factors, which determine the relative light intensity in the understorey, using profile- and crown-projection diagrams related to relative light intensity (RLI) measured one metre above the ground. The horizontal pattern showed a fine-grained mosaic of trees in different developmental phases resulting in a variable canopy height ranging from 1 to 40 m. Beneath the canopy one to three understorey layers were common. The main reasons for this well developed stratification were irregularity in canopy cover among small neighbouring structural units and the presence of four co-occurring tree species with different reproductive strategies and life cycles. Relating the spatial structure to the understorey light intensity, we found the continuous cover of dense growing understorey layers across neighbouring structural units to be the main determinant for RLI.

Canopy stratification in tropical seasonal forests: How the functional traits of community change among the layers

Article

Full-text available

Sep 2014

The discussion of the existence and measurement of layers in forests refers to one of the earliest and most controversial concepts of forest ecology, the stratification. Since there is no consensus on the most appropriate methodology to describe the vertical structure of forest communities, we chose for this paper to develop a methodology that was adequate to represent the stratification observed on site. The objective was to determine the species and functional traits characteristic of each vertical layer in the semideciduous seasonal forests (SSF). The study was conducted in ten fragments (10 ha) located in southeastern Brazil. Stratification was performed according to species using the median and the 3 rd quartile (non-parametric statistical analysis) of tree heights were used for canopy stratification the (understory, midstory and canopy). This result shows the small range of the midstorey layer, highlighting the dichotomy between the canopy and understory. The variations found for the quartile and median values represent the history of successional stage of each fragment, allowing variations in the vertical occupation by species of certain layers. The analysis of SSF vertical structure allowed a visualization of the division of species and their respective functional traits performing different ecosystem functions in each layers.

Creation of multi-layered canopy structures in young oak-dominated urban woodlands – The ‘ecological approach’ revisited

Article

Dec 2012

Additivity of stand basal area predictions in canopy stratifications for natural oak forests

Article

Jul 2021
FOREST ECOL MANAG

Stand basal area is an important variable for evaluating forest productivity. In this study, four types of growth models were used for modeling the stand basal area of natural oak forests in Hunan Province, China. The results showed that the Schumacher model (Eq. (3)) performed the best. Because of different canopy layers in natural oak secondary forests, it is important to develop stand basal area models considering canopy stratification. Three widely used canopy stratification methods were used for natural oak forests: the clustering analysis of tree height, classification scheme of the International Union of Forest Research Organizations (IUFRO) standard, and canopy competition cutoff height (CCH) method. According to the standards set forth in the National Standards of the People's Republic of China (GB/T 26424-2010), the forests were divided into two layers: upper and lower. Among the three canopy stratification approaches, the IUFRO method was selected as the best. In addition, it should be noted that the sum of the basal area predictions at different layers can generate inconsistent results, as compared to predictions from the total stand basal area model. To solve the additivity of stand basal area predictions , the additive stand basal area growth model was established by nonlinear seemingly unrelated regression (NSUR). Comparing with the whole stand basal area growth model without stratification, the R 2 values of basal area growth models with stratification increased by 4.78% (from 0.9277 to 0.9721). In addition, compared with equations estimated separately, the NSUR method increased R 2 by 0.82% (from 0.9721 to 0.9801). The results reveal that the NSUR method can be applied to solve the additivity of stand basal area predictions at each layer and can improve model precision, which provides helpful insights into developing stand growth models in natural forests.

Evaluating tropical forest classification and field sampling stratification from lidar to reduce effort and enable landscape monitoring

Article

Nov 2019
FOREST ECOL MANAG

In high biodiversity areas, such as the Amazon, forest inventory is a challenge due to large variations in vegetation structure and inaccessibility. Capturing the full gradient of variability requires the acquisition of a large number of sample plots. Pre-stratified inventory is an efficient strategy that reduces sampling effort and cost. Low-cost remote sensing techniques may significantly expand pre-stratification capacity; however, the simplest option, satellite optical imagery, cannot detect small variations in primary forests. Alternatively, three-dimensional information obtained from airborne laser scanning (ALS, a.k.a. airborne lidar) has been successfully used to estimate structural parameters in tropical forests. Our objective was to assess to what extent forest plot sampling effort could be reduced, while accurately estimating mean vegetation characteristics in the landscape, by stratifying with ALS structural properties, relative to a random, uniformed conventional approach. The study was developed in an 800-ha area of wet Amazonian forest (Acre, Brazil), including portions of palms, bamboo and dense forest. We estimated relevant structural attributes from ALS: canopy height, openness, rugosity and fractions of leaf area index (LAI) along the vertical profile. We clustered vegetation to define heterogeneity into structural types, employing the Ward method and Euclidean distance. Also, principal component analysis was employed to characterize the groups using field and ALS-derived structural attributes. We simulated sampling intensities to estimate the gain in reducing the field efforts based on pre-stratified and non-stratified forest inventory scenarios. The resulting stratification clearly distinguished the forest’s structural variation gradient and the vegetation density profile. For a fixed uncertainty of 10% in basal area estimation, the ALS-aided stratified inventory reduced the necessary number of field plots by 41%, relative to simple random sampling. The resulting reduction in sampling effort can offset the cost of ALS data collection, significantly enhancing its financial feasibility. In addition, ALS provides broad-coverage quantifications of basal area (or aboveground carbon stock), canopy structure, and accurate terrain characterization, which have an added value for forest management.

Singh etal 2015

Data

Feb 2015

Effects of LiDAR point density and landscape context on estimates of urban forest biomass

Article

Full-text available

Feb 2015
ISPRS J PHOTOGRAMM

Light Detection and Ranging (LiDAR) data is being increasingly used as an effective alternative to conven-tional optical remote sensing to accurately estimate aboveground forest biomass ranging from individual tree to stand levels. Recent advancements in LiDAR technology have resulted in higher point densities and improved data accuracies accompanied by challenges for procuring and processing voluminous LiDAR data for large-area assessments. Reducing point density lowers data acquisition costs and over-comes computational challenges for large-area forest assessments. However, how does lower point den-sity impact the accuracy of biomass estimation in forests containing a great level of anthropogenic disturbance? We evaluate the effects of LiDAR point density on the biomass estimation of remnant forests in the rapidly urbanizing region of Charlotte, North Carolina, USA. We used multiple linear regression to establish a statistical relationship between field-measured biomass and predictor variables derived from LiDAR data with varying densities. We compared the estimation accuracies between a general Urban For-est type and three Forest Type models (evergreen, deciduous, and mixed) and quantified the degree to which landscape context influenced biomass estimation. The explained biomass variance of the Urban Forest model, using adjusted R 2 , was consistent across the reduced point densities, with the highest dif-ference of 11.5% between the 100% and 1% point densities. The combined estimates of Forest Type bio-mass models outperformed the Urban Forest models at the representative point densities (100% and 40%). The Urban Forest biomass model with development density of 125 m radius produced the highest adjusted R 2 (0.83 and 0.82 at 100% and 40% LiDAR point densities, respectively) and the lowest RMSE val-ues, highlighting a distance impact of development on biomass estimation. Our evaluation suggests that reducing LiDAR point density is a viable solution to regional-scale forest assessment without compromis-ing the accuracy of biomass estimates, and these estimates can be further improved using development density.

Frontiers in using LiDAR to Analyze Urban Landscape Heterogeneity.

Thesis

Full-text available

Jan 2014

Kunwar K. Singh

SINGH, KUNWAR KRISHNA VEER. Frontiers in using LiDAR to Analyze Urban Landscape Heterogeneity. (Under the direction of committee chair Ross K. Meentemeyer.) Light Detection and Ranging (LiDAR) technology has facilitated extraordinary advances in our ability to remotely sense precise details of both built and natural environments. The inherent complexity of urban landscapes and the massive data volumes produced by LiDAR require unique methodological considerations for big data remote sensing over large metropolitan regions. The heterogeneous landscapes of the rapidly urbanizing Charlotte Metropolitan Region of North Carolina provided an ideal testing ground for developing methods of analysis for urban ecosystems over large regional extents, including: (1) fusion of LiDAR digital surface models (DSMs) with Landsat TM imagery to balance spatial resolution, data volume, and mapping accuracy of urban land covers, (2) comparison of LiDAR-derived metrics to fine grain optical imagery – and their integration – for detecting forest understory plant invaders, and (3) data reduction techniques for computationally efficient estimation of aboveground woody biomass in urban forests. In Chapter 1, I examined tradeoffs between potential gains in mapping accuracy and computational costs by integrating DSMs (structural and intensity) extracted from LiDAR with TM imagery and evaluating the degree to which TM, LiDAR, and LiDAR-TM fusion data discriminated land covers. I used Maximum Likelihood and Classification Tree algorithms to classify TM data, LiDAR data, and LiDAR-TM fusions. I assessed the relative contributions of LiDAR DSMs to map classification accuracy and identified an optimal spatial resolution of LiDAR DSMs for large area assessments of urban land cover. In Chapter 2, I analyzed combinations of datasets developed from categorized LiDAR-derived variables (Overstory, Understory, Topography, and Overall Vegetation Characteristics) and IKONOS imagery (Optical) to detect and map the understory plant invader, Ligustrum sinense, using Random Forest (RF) and logistic regression (LR) algorithms, and I assessed the relative contributions of sensors and forest landscape structures. I compared the top performing models developed using RF and LR and used the best overall model to map the distribution of L. sinense occurrence across the urbanizing forest landscapes of the region. In chapter 3, I examined the effects of LiDAR point density and landscape context on the estimation of

Characterization of Canopy Layering in Forested Ecosystems Using Full Waveform Lidar

Article

Full-text available

Apr 2013

Canopy structure, the vertical distribution of canopy material, is an important element of forest ecosystem dynamics and habitat preference. Although vertical stratification, or "canopy layering," is a basic characterization of canopy structure for research and forest management, it is difficult to quantify at landscape scales. In this paper we describe canopy structure and develop methodologies to map forest vertical stratification in a mixed temperate forest using full-waveform lidar. Two definitions-one categorical and one continuous-are used to map canopy layering over Hubbard Brook Experimental Forest, New Hampshire with lidar data collected in 2009 by NASA's Laser Vegetation Imaging Sensor (LVIS). The two resulting canopy layering datasets describe variation of canopy layering throughout the forest and show that layering varies with terrain elevation and canopy height. This information should provide increased understanding of vertical structure variability and aid habitat characterization and other forest management activities.

Disturbance history and historical stand dynamics of a seasonal tropical forest in western Thailand

Article

Aug 2005

Disturbances influence forest dynamics across a range of spatial and temporal scales. In tropical forests most studies have focused on disturbances occurring at small spatial and temporal scales (i.e., gap dynamics). This is primarily due to the difficulty of reconstructing long‐term disturbance histories of forests in which most tree species lack annual growth rings. Consequently, the role of past disturbances in tropical forests is poorly understood. We used a combination of direct and indirect methods to reconstruct the historical disturbance regime and stand development patterns in mature and regenerating seasonal dry evergreen forest (SDEF) in the Huai Kha Khaeng Wildlife Sanctuary in western Thailand. Direct estimates of long‐term establishment and growth patterns were obtained from 12 tree species that form annual growth rings as a consequence of the region's strong intra‐annual rainfall seasonality. Indirect estimates of establishment patterns were obtained from analyses of stand structure and individual tree architecture and application of age‐estimation models to 10 dominant canopy‐tree species using demographic data from a large‐scale, permanent forest‐dynamics plot. The combination of direct and indirect methodologies revealed a complex disturbance history in the seasonal evergreen forest over the past 250 years. In the mid‐1800s, 200–300 ha of forest were destroyed by a catastrophic disturbance, which led to the synchronous establishment of many of the trees that presently dominate the forest canopy. Since then widespread disturbances of variable intensity have occurred at least three times (1910s, 1940s, and 1960s). These disturbances created discrete temporal pulses of establishment in small to large gaps in the forest matrix across several square kilometers. Background mortality and gap formation were evident in every decade since 1790, but these varied in intensity and frequency. The SDEF retains a distinct structural and floristic legacy from the catastrophic disturbance of the mid‐1800s. The single‐age cohort that established after the disturbance has developed a complex three‐dimensional structure as a consequence of differences in interspecific growth patterns of the canopy‐tree species and subsequent disturbances of moderate and low intensity. While no single methodological approach provided a complete picture of the disturbance history and stand development patterns of the seasonal evergreen forest, taken together they offered new insights into the long‐term dynamics of a primary tropical forest. In particular, the study highlighted the role of disturbance at multiple spatial and temporal scales and varying intensities in determining the structure and composition of a complex, species‐rich tropical forest and raises important questions about the role of rare, catastrophic events on tropical forest dynamics.

Importance of structure and its measurement in quantifying function of forest ecosystems

Article

Full-text available

Nov 2010

The structure of forests, the three-dimensional arrangement of individual trees, has a profound effect on how ecosystems function and cycle carbon, water, and nutrients. The increased need to understand local to global dynamics of ecosystems, a prerequisite to understand the coupling of the biosphere to other components of Earth systems, has created a demand for extensive ecosystem structure data. Repeated satellite observations of vegetation patterns in two dimensions have made significant contributions to our understanding of the state and dynamics of the global biosphere. Recent advances in remote sensing technology allow us to view the biosphere in three dimensions and provide us with refined measurements of horizontal, as well as vertical, structure of forests. This paper provides an introductory review of the importance of the three-dimensional characterization of terrestrial ecosystem structure of forests and woodlands and its potential measurement from space. We discuss the relevance of these measurements for reducing the uncertainties of terrestrial carbon cycle and the response of ecosystems to future climate. By relating the 3-D structure to forest biomass, carbon content, disturbance characteristics, and habitat diversity, we examine the requirements for future satellite sensors in terms of precision and spatial and temporal resolutions. In particular, we focus this review on measurements from lidar and radar sensors that provide vertical and horizontal characterization of vegetation and are currently recommended for next generation of NASA's Earth observing and European Earth Explorer systems.

Estimating Forest Above-Ground Biomass in Central Amazonia Using Polarimetric Attributes of ALOS/PALSAR Images

Article

Full-text available

May 2023

Polarimetric synthetic aperture radar (SAR) images are essential to understand forest structure and plan forest inventories with the purpose of natural resource management and environmental conservation efforts. We developed a method for estimating above-ground biomass (AGB) from power and phase-radar attributes in L-band images. The model was based on the variables “Pv” (from Freeman–Durden decomposition) and “σ°HH”, complemented by the attributes of Touzi decomposition “αS2”, “τm”, “ ΦS3”, and “ ΦS2”. The analyses demonstrated the contribution of volumetric, multiple, and direct scattering resulting from the interaction between the signal and the random structure of canopies and their forest biomass. The proposed model had good predictive capacity and a positive correlation (R2 = 0.67 and = 0.81, respectively), with Syx = 56.9 Mg ha−1 and a low average estimation error of 7.5% at R2 = 0.81 in the validation. An additional exploratory analysis of the parallel polarimetric responses did not reveal a defined pattern for the different phytophysiognomies—although all indicated a predominance of multiple and/or volumetric scattering. This fact can be related to the floristic and structural variation in the primary forest units, the degree of human intervention in legal logging, and the differences among succession stages.

KEANEKARAGAMAN HAYATI TUMBUHAN DI SEKITAR KAWASAN BENDUNGAN LABUHAN KECAMATAN BATANG ALAI SELATAN KALIMANTAN SELATAN

Article

Full-text available

Jun 2022

Biodiversity in species, and ecosystems is decreasing at a dangerous rate due to environmental damage. One method to describe a vegetation is vegetation analysis. This study aims to determine plant biodiversity and stand structure profile diagrams to provide an overview of vegetation conditions in the Labuhan DAM area. Determination of the location of the sample using the path method determined on the right and left of the river before and after the dam with a path length of 40 mx 20 m. Based on the analysis, the results found 10 species of understorey, 13 types of trees and the dominant tree canopy stratification, namely trembesi and alaban.Keanekaragaman hayati pada spesies, dan ekosistem semakin menurun pada tingkat yang membahayakan akibat kerusakan lingkungan. Salah satu metode untuk mendeskripsikan suatu vegetasi yaitu analisis vegetasi. Penelitian ini bertujuan untuk mengetahui keanekaragaman hayati tumbuhan dan diagram profil struktur tegakan guna memberikan gambaran kondisi vegetasi di kawasan Bendungan Labuhan. Penentuan lokasi sampel menggunakan metode jalur yang ditentukan pada kanan kiri sungai sebelum dan sesudah bendungan dengan panjang jalur 40 m x 20 m. Berdasarkan analisis diperoleh hasil ditemukan 10 jenis tumbuhan bawah 13 jenis pohon dan stratifikasi tajuk pohon yang dominan yaitu trembesi dan alaban.

TREE STRATIFICATION BASED ON ERUPTION DAMAGE LEVEL IN MOUNT MERAPI NATIONAL PARK YOGYAKARTA INDONESIA

Article

Full-text available

Apr 2021

Mount Merapi's eruption has caused damage to the forests in the Mount Merapi National Park (MMNP). Nine years after the eruption, the vertical structure of vegetation can illustrate the progress of succession. This study aimed to analyze the tree composition and stratification in different forest damage levels after the 2010 Merapi eruption. The study was conducted in March 2019 at three stations, namely station A (heavy damage area), station B (moderate damage area), and station C (minor damage area). Vegetation parameters in each station were taken in a 10x100 plot and were processed using a tree profile diagram. Abiotic parameters were measured in each plot and analyzed using the correlation test. The results showed that the three stations were still dominated by the tree in Stratum C, but the tree density and tree height varied in proportion to the damage level. Station A in the heavy damage area has the lowest tree density (23 trees/0.1 ha) with a maximum tree height of 12 meters, in contrast to Station C in the minor damage area with tree density reaching 195 trees/0.1 ha and maximum tree height reaching 30 meters. Nine years after the Mount Merapi big eruption, the MMNP forests in Yogyakarta Province are still classified as young secondary forests.

Seeing beyond the trees: a comparison of tropical and temperate plant growth forms and their vertical distribution

Article

Full-text available

Feb 2020
ECOLOGY

Forests are the most diverse and productive terrestrial ecosystems on Earth, so sustainably managing them for the future is a major global challenge. Yet, our understanding of forest diversity relies almost exclusively on the study of trees. Here, we demonstrate unequivocally that other growth forms (shrubs, lianas, herbs, epiphytes) make up the majority of vascular plant species in both tropical and temperate forests. By comparing the relative distribution of species richness among plant growth forms for over 3,400 species in 18 forests in the Americas, we construct the first high‐resolution quantification of plant growth form diversity across two ecologically important regions at a near‐continental scale. We also quantify the physical distribution of plant species among forest layers, that is, where among the vertical strata plants ultimately live their adult lives, and show that plants are strongly downshifted in temperate forests vs. tropical forests. Our data illustrate a previously unquantified fundamental difference between tropical and temperate forests: what plant growth forms are most speciose, and where they ultimately live in the forest. Recognizing these differences requires that we re‐focus ecological research and forest management plans to encompass a broader suite of plant growth forms. This more holistic perspective is essential to conserve global biodiversity.

Phytosociology of stratification in a lowland tropical rainforest occurring north of the Tropic of Cancer in Meghalaya, India

Article

Full-text available

Aug 2019

Uma Shankar

Stratification in lowland rainforests of Meghalaya, India, which represent the westernmost limit of the rainforests north of the Tropic of Cancer, was studied in horizontal and vertical planes to elucidate the patterns in stacking of species diversity and community attributes, and to draw comparisons with rainforests of ‘Indo-Malaya’ ecozone (biogeographical realm). All individuals ≥10 cm GBH (girth at breast height) were enumerated in six transects of 10 m width and up to 500 m length covering 2.45 ha area. The stratification of whole assemblage of species in vertical plane is referred to as ‘storey structure’ (=height class distribution), which explains structural complexity. In horizontal plane, it is typically referred to as ‘stand structure’ (=girth class distribution), which explains structural heterogeneity. The stratification of an individual species in vertical plane is referred to as ‘loftiness’ and in horizontal plane, it is frequently referred to as ‘population structure’. The stand structure was characterized by a negative exponential relationship or a reverse J-shaped curve, which is typical of a well regenerating forest stand. The storey structure was characterized by the low stature of the rainforest (

Short Communication: Species composition and density of mangrove forest in Kedawang Village, Pasuruan, East Java, Indonesia

Article

Full-text available

May 2019

Isroni W, Islamy RA, Musa M, Wijanarko P. 2019. Short Communication: Species composition and density of mangrove forest in Kedawang Village, Pasuruan, East Java. Biodiversitas 20: 1688-1692. Mangrove is one of ecosystems located in estuary and shallow coastal waters and its existence has a significant role for life. The aim of this study was to identify species composition and density of mangrove forest in Kedawang village, Nguling Sub-district, Pasuruan District, East Java, Indonesia. Survey method using belt transects was carried at three sampling points. Results of this study showed that mangrove vegetation in Kedawang includes five species from three families, namely Avicenniaceae (Avicennia alba and Avicennia marina), Rhizophoraceae (Rhizophora apiculata and Rhizophora mucronata), and Sonneratiace (Sonneratia alba). At sampling point 1, A. alba dominated with a density of 37 individuals/ha at tree level, 380 individuals/ha at pole level and 3100 individuals/ha at stake level. At sampling point 2, the tree level was dominated by A. alba with 142 individuals/ha, while R. mucronata dominated the pole and stake level with 1300 and 1467individuals/ha, respectively. At sampling point 3, the pole and stake level was dominated by A. alba with 167 and 933 individuals/ha respectively, while A. marina dominated the sapling level with 800 individuals/ha. At all stations, the density at stake level is greater than that tree level. Therefore, it is necessary to carry out conservation efforts in the form of protection combined with restoration by enrichment planting at all study locations to increase the diversity and density of mangrove vegetation.

Short Communication: Population and stand structure of Cinnamomum sintoc in the Low Land Forest of Mount Ciremai National Park, West Java, Indonesia

Article

Full-text available

Apr 2019

Ismail AY, Kusmana C, Sudiana E, Widodo P. 2019. Short Communication: Population and stand structure of Cinnamomum sintoc in the Low Land Forest of Mount Ciremai National Park, West Java, Indonesia. Biodiversitas 20: 1042-1047. Cinnamomum sintoc (C. sintoc) is one of the anthelmintic and anti-inflammatory medicinal plants which produces essential oils from its roots, skin, and leaves. This study aimed to analyze the population and stand structure of C. sintoc in Mount Ciremai National Park, West Java, Indonesia. Data collection was carried out using plots/ strips method. The plots were purposively placed and made at each altitude and direction of the slope. The research recorded 804 individual trees from each growth edge. Individual density between slope directions and altitudes was not significantly different for all diameter classes, but was significantly different between slope directions of stratum B (P = 0.001) and E (P = 0.012). These results indicate that sintoc population is spread evenly and can be cultivated at various slope and altitude directions and has no preference for the two topographic variables.

Using airborne laser scanning to predict plant species richness and assess conservation threats in the oil sands region of Alberta's boreal forest

Article

Feb 2018
FOREST ECOL MANAG

Timely and cost-effective monitoring of biodiversity across large areas is a major challenge, yet an important component of monitoring programs that inform policy and conservation strategies. Recent advances in Airborne Laser Scanning (ALS) provide new opportunities to simultaneously measure vegetation structure and terrain morphology at fine spatial scales. However, there is limited research on whether ALS metrics correlate with biodiversity measures. Here we used vascular plant data from 283 quarter-hectare (50 m × 50 m) plots from the boreal forest in northeast Alberta, Canada, to evaluate the potential for ALS-derived metrics to explain species richness patterns for vascular plants, as well as for four growth forms: herbaceous (including forbs and graminoids) and woody plants. We found canopy height from ALS was the most consistent and important (positive) factor related to local patterns in vascular plant species richness. Multivariate regression models of ALS-derived metrics explained 20–35% of the variation in species richness among vascular plants and the four subclasses. When considering the current distribution of in situ oil sands leases in the region, vascular plant richness inside of the leases is higher than outside. Areas delineated for woodland caribou conservation had lower average plant richness suggesting that it will do little to protect hotspots of vascular plant diversity in Alberta's boreal forest. Our results highlight the value of using fine-scale measures of ALS-derived vegetation structure to explain, predict, and potentially monitor local plant diversity for a high latitude forested ecosystem.

Flora vascular, estrutura comunitária e conservação de fragmentos da floresta atlântica na Bacia Hidrográfica do Rio Cachoeira, Joinville, SC, Brasil

Article

Full-text available

Dec 2017

Este estudo objetivou conhecer a flora e a estrutura de áreas remanescentes da floresta atlântica inseridas na Bacia Hidrográfica do Rio Cachoeira, município de Joinville, Santa Catarina. Selecionaram-se os cinco maiores fragmentos florestais em extensão localizados na área urbana do município, além do canal do rio principal da bacia, para o levantamento da flora aquática. As coletas foram realizadas mensalmente em todas as áreas amostrais. A organização sistemática da flora adotou o sistema APG IV. Amostrou-se um total de 381 espécies distribuídas em 226 gêneros e 89 famílias. As famílias mais ricas foram: Myrtaceae (35), Fabaceae (29), Rubiaceae (22), Bromeliaceae (20), Asteraceae (17), Lauraceae (16), Poaceae (14), Cyperaceae (13), Sapindaceae (11) e Araceae (10). As cinco espécies de maior valor de importância foram Euterpe edulis, Alchornea triplinervia, Psychotria nuda, Hyeronima alchorneoides e Ficus gomelleira. Os fragmentos apresentaram elevado índice de diversidade e baixa similaridade entre si. Aproximadamente 50% dos indivíduos compuseram classes de altura e diamétrica inferiores. Os fragmentos estão, em sua maioria, em estádio sucessional médio de regeneração natural. Os resultados indicam a importância desses fragmentos como áreas relictuais para a conservação da diversidade da floresta atlântica em áreas urbanas.

Assessing high compositional differences of beetle assemblages across vertical woodland strata in the New Forest, Hampshire, England

Article

Full-text available

Jul 2016

Closed-canopy woodlands are complex ecosystems with strong vertical environmental stratification. The degree to which this vertical stratification has led to compartmentalisation in invertebrate assemblages in temperate woodlands has been researched to a limited extent, yet there are still gaps in our understanding. Here, we used five different sampling methods to sample beetles across vertical strata of nine woodland sites in the New Forest National Park, Hampshire, England. The sampling methods yielded 2412 individuals across 157 species, of which 46 were significant indicator species for one stratum or a combination of strata. Multivariate analysis of composition showed a strong separation at a subfamily level between strata, with many only found in a single stratum. This suggests a strongly compartmentalised vertical stratification of the beetle assemblages at both species and higher taxonomic levels. Our results display that multiple strata need to be sampled to obtain true estimates of overall beetle species richness in woodlands and forests. Limitations in using a single sampling method and biases using mixed sampling method protocols across a vertical transect are also discussed.

Sampling in Forest Inventories

Chapter

Jan 2016

In sampling, a part of a population is selected and used to obtain estimates of characteristics of that population. The current chapter gives an overview on sampling methods applied in the scope of forest inventories, describes their general approaches and estimation procedures, and discusses advantages and disadvantages of the individual designs. Fixed area plots and point sampling for the selection of trees on sampling units are presented. Alternative designs for the estimation of change by sampling on successive occasions are introduced. The final section gives an overview of sampling and non-sampling errors occurring in forests surveys.

Forest Canopies as Earth’s Support Systems: Priorities for Research and Conservation

Chapter

Full-text available

May 2013

In this chapter we address three sets of questions about the present and future role of canopy science within the larger context of forest science. First we review research that either promotes or constrains canopy science as a distinct field. Second, we examine what is known about how canopies are being altered by human use of tropical forests, and consider priorities for research in human interactions with forest canopies. Third, we ask how canopy science can help address the urgent need to understand patterns of human impacts and global environmental changes, specifically in tropical forest ecosystems. It is evident from this volume that canopy researchers are shifting their priorities toward forest canopy conservation by embracing whole-forest approaches with reference to ecosystem services, forest health, climate change, sustainability science, economics, education, and the social sciences.

Assessment of forest canopy vertical structure with multi-scale remote sensing: from the plot to the large area

Thesis

Full-text available

Jan 2016

Phil Wilkes

The attribution of forest structure forms an integral part of international monitoring and reporting obligations with regard to sustainable forest management. Furthermore, detailed information about forest structure allows land managers and forest scientists to determine a forests ability to provide ecosystems services. Currently, forest attribution is achieved using a network of forest inventory plots that are revisited periodically. This approach comprises a sparse sample, both temporally and spatially, that may not capture variance in forest structure. This is particularly true in dynamic native forests where variability in forest structure can be high. In recent years the capability of remote sensing techniques has been realised for sustainable forest management applications. Advantages of a remote sensing approach include synoptic and high temporal coverage as well as reduced costs to the end-user. Furthermore, recent advancement in active sensors, such as Light Detection and Ranging Instruments (LiDAR) have allowed for detailed three-dimensional forest measurement of structure across large areas. This thesis presents new metrics, techniques and acquisition specifications for the attribution of forest canopy over large areas (e.g. comprising two or more forest types where forest structure maybe unknown a priori) using active and passive remote sensing. In particular, the focus is on attributes that quantify the vertical structure of forests; canopy height and canopy vertical structure. Canopy height is a commonly measured multipurpose attribute that is utilised, for example, to estimate biomass. Attribution of the canopy height profile, although less common, is important for mapping habitat suitability, biomass and fire susceptibility. Current techniques to attribute forests tend to be tailored to a particular forest type or location and therefore application of these models across large areas is unreliable. Here the aim is to develop metrics and techniques that are transferable between different forest types and applicable to forests where there is no prior knowledge of forest structure. Here a multi-scale remote sensing approach was taken, where plot scale measurements were upscaled to attribute large areas. Initially, existing LiDAR derived metrics applicable at the plot scale were tested at three 5 km x 5 km study areas in Victoria, Australia where forests cover a broad range of structural types. Results indicate existing metrics of canopy height were applicable across the range of forest types, for example the 95th percentile of LiDAR derived height estimated inventory measured canopy height with a RMSE of 12% (~5 m). An existing mixture modelling technique to attribute the canopy height profile was found unsuitable when applied across heterogeneously forested landscape. This was due to the inability to parameterise the model correctly without a priori knowledge of forest structure e.g. presence or absence of shade tolerant layers. For this reason a new technique was developed utilising a nonparametric regression of LiDAR derived gap probability that generalised the canopy profile. Taking the second derivative of the regression curve identified locations within the canopy that correspond with canopy strata, this therefore allowed a dynamic attribution of canopy vertical structure. Model output was validated with a crown volume modelling approach at 24 plots, where crown models were parameterised with inventory data and allometry. Results indicate this technique can estimate the number of canopy strata with a RMSE of 0.41 strata. Furthermore, the new technique met the transferability criteria, as a universal regression coefficient was transferable between forest types with different structural attributes. As LiDAR acquisition that cover large areas will inevitably encounter a range of forest types, parameters for attributing canopy structure that were transferable between forest types were investigated; in particular sampling frequency. To effectively assess a range of pulse densities would require repeat capture over a study area at a range of flying heights, which would be prohibitively expensive. For this reason a new technique was developed that systematically thinned point clouds. This technique differs from previous approaches by allowing simulation of multi-return instruments as well as repeat capture of the same plot. Six sites from around Australia were utilised which covered a broad range of forest types, from open savanna to tropical rainforest. For a suite of metrics, the ability of progressively less dense point clouds (4 – 0.05 pl m-2) to estimate canopy structure was estimated by comparison with higher density data (10 pl m-2). Results indicate that canopy structure can be adequately attributed with data captured at 0.5 pl m-2. When pulse densities are <0.5 pl m-2, the inability to adequately identify ground resulted in poor metric estimation, this was particularly evident in high biomass forest. Conversely at lower pulse densities in savanna systems, the inability to characterise sparse vegetation resulted in poor attribution of the canopy profile. Techniques derived at the plot scale were then applied to estimate canopy height across 2.9 million hectares of heterogeneous forest. Canopy height in the study area ranged from 0 – 70 m and comprised forest types from open woodland to tall closed canopy rainforest. LiDAR derived canopy height was used to train ensemble regression trees (random forest), where predictor datasets included synoptic passive optical imagery and other ancillary spatial datasets, such as Landsat TM and MODIS. Results suggest canopy height can be estimated with a RMSE of 30% (5.5 m) when validated with an independent inventory dataset. This is a similar error to that reported in previous studies for less complex forests and is within the European Space Agency target for canopy height estimation. However, model output did show a systematic error, where the height of short and tall forests were over and underestimated respectively. This was corrected by subtracting a modelled estimate of error from the random forest output. Production of a canopy height map over a large area allowed for a consistent product that covered a broad range of forest types, derivation at a 30 m resolution allowed the identification of landscape features such as logging coupes. The presented technique utilised an open source computing framework as well as freely available predictor datasets to facilitate uptake of by land management agencies and forest scientists.

Characterization of Brazilian forest types utilizing canopy height profiles derived from airborne laser scanning

Article

Full-text available

Jul 2016
APPL VEG SCI

Questions This study explores how airborne laser scanning surveys can contribute to characterizing and discriminating different Brazilian forest types based on canopy height profiles, and how sampling intensity and plot size affect the results. Location Seven different vegetation types in Brazil – open ombrophilous Amazonian forest type in the state of Pará State, dense ombrophilous Atlantic forest in the state of São Paulo, semi‐deciduous and rupestrian field in the state of Minas Gerais, and three fast‐growing eucalyptus plantations in the state of São Paulo. Methods Canopy height profiles were modelled for each forest type using a two‐parameter Weibull distribution. Differences in the values of the Weibull cumulative distribution parameters were studied to evaluate their discriminative capacity. Simulation was subsequently used to determine the number of cells needed to define a reliable sampling intensity for each cell size tested. Eight grid cell sizes were tested against six sampling intensities using 1000 iterations for all seven forest types. Results Each forest presented distinct characteristics regarding the canopy height profile. The higher presence of ground returns was remarkable in less layered structured forests (i.e. rupestrian field and eucalyptus plantations). Depending on the forest type, monotonic and sigmoidal shapes were observed for the cumulative distribution function of the canopy height profile. A sigmoidal cumulative distribution function was typical of a more layered structure (dense and open ombrophilous, and semi‐deciduous), whereas less structured typologies (i.e. Rupestrian field and forest plantation) were associated with monotonically shaped functions. Modelling convergence for the canopy height profile was achieved in most cases with data representing at least 2% cover. Conclusion Canopy height profiles generated from ALS data proved different among five different forest types: open ombrophilous, dense ombrophilous, semi‐deciduous, rupestrian field and eucalyptus plantations. Furthermore, large‐scale forest inventories can benefit from the results observed in this study, as it provides recommendations on grid cell size and sampling intensity levels.

The structure of tropical forests and sphere packings

Article

Nov 2015

Significance Explaining the tree size structure of tropical forests is of crucial importance because other important forest attributes can be derived from this. The tree diameter distribution, for example, determines the amount of carbon stored in a forest. Here we present a simple and powerful approach based on stochastic geometry and tree allometries that can be used to predict tree diameter distributions.

LiDAR technology applied to vegetation quantification and qualification

Thesis

Full-text available

Dec 2014

Eric Bastos Gorgens

The methodology to quantify vegetation from airborne laser scanning (or LiDAR - Light Detection And Ranging) is somehow consolidated, but some concerns are still in the checklist of the scientific community. This thesis aims to bring some of those concerns and try to contribute with some results and insights. Four aspects were studied along this thesis. In the first study, the effect of threshold heights (minimum height and height break) in the quality of the set of metrics was investigated aiming the volume estimation of a eucalyptus plantation. The results indicate that higher threshold height may return a better set of metrics. The impact of threshold height was more evident in young stands and for canopy density metrics. In the second study, the stability of the LiDAR metrics between different LiDAR surveys over the same area was analyzed. This study demonstrated how the selection of stable metrics contributed to generate reliable models between different data sets. According to our results, the height metrics provided the greatest stability when used in the models, specifically the higher percentiles (>50%) and the mode. The third study was designed to evaluate the use of machine learning tools to estimate wood volume of eucalyptus plantations from LiDAR metrics. Rather than being limited to a subset of LiDAR metrics in attempting explain as much variability in a dependent variable as possible, artificial intelligence tools explored the complete metrics set when looking for patterns between LiDAR metrics and stand volume. The fourth and last study has focused upon several highly important forest typologies, and shown that it is possible to differentiate the typologies through their vertical profiles as derived from airborne laser surveys. The size of the sampling cell does have an influence on the behavior observed in analyses of spatial dependence. Each typology has its own specific characteristics, which will need to be taken into consideration in projects targeting monitoring, inventory construction, and mapping based upon airborne laser surveys. The determination of a converged vertical profile could be achieved with data representing 10 % of the area for all typologies, while for some typologies 2 % coverage was sufficient.

Linking vertebrate species richness to tree canopy height on a global scale

Article

Full-text available

Jun 2015

Aim: In this paper we explore global links between tree canopy height and species richness of amphibians, birds and mammals. We follow the ideas first laid out by MacArthur and MacArthur in 1961 who found that in the eastern USA higher tree canopies supported more bird species, which they attributed to an increase of available niches as forests grow taller. We test if their findings can be generalized over large regions and other taxa by employing novel methods and using current datasets. Location: Global Methods: We used the global distribution maps of the three above taxa to infer species richness. Our tree canopy height information was derived from remotely sensed LiDAR data. The analysis was conducted globally and within biogeographical realms. We modeled richness, using tree canopy height and other environmental correlates, with generalized additive models and geographically weighted regressions. Results: Globally, tree canopy height proved to be of lesser importance in explaining species richness patterns compared to other environmental drivers. Within biogeographical realms, tree canopy height was found to be a more important predictor of diversity in the Neotropic and Australian realms. Regional patterns show that tree canopy height has an important effect on diversity of amphibians throughout the world and in several tropical regions across taxa. Net Primary Productivity (NPP) explains more of the variation in richness both globally and within most regions. Main Conclusions: Overall, tree canopy height is not an important predictor of diversity. However we highlight its relative importance in particular locations and settings.

CARACTERIZAÇÃO ESPAÇOTEMPORAL DE DUAS FLORESTAS ESTACIONAIS DO OESTE BAIANO, BARREIRAS-BA - DOI 10.5216/bgg.v32i1.18961

Article

Full-text available

Jun 2012

Em estudos com fitofisionomias do Bioma Cerrado, as florestas estacionais estiveram entre as formações com maior carência de estudo. Apesar do aumento expressivo de pesquisas nos últimos anos, elas se concentram em estados do sul e sudeste brasileiro, já em boa parte do Cerrado nordestino, ainda há muitas lacunas no conhecimento dos processos ecológicos que as envolvem. Este artigo tem como objetivo suprir parte dessa deficiência ao descrever a estrutura espacial e a dinâmica da cobertura vegetal de duas florestas estacionais. Ao longo da paisagem regional, essas fitofisionomias, em que estão restritas a eixos de drenagem próximos às vertentes dos chapadões dominantes na região. Para a avaliação espaço-estrutural das duas fitofisionomias, foram elaborados diagramas de perfis de vegetação e análise florística, já a dinâmica temporal foi observada através do cálculo do Índice de Área Foliar (LAI) das estações chuvosa e seca usando como referência imagens de satélite. Averiguou-se que as florestas estudadas possuem características estruturais e florísticas diferenciadas, as quais têm papel fundamental na dinâmica temporal percebida pelo LAI, cujos índices são semelhantes na estação chuvosa, distinguindo-se significativamente na estação seca. Este estudo demonstra a importância dessas metodologias na definição de unidades da paisagem.

Individual Tree Simulation and Stand Visualization of Pinus Tabulaeformis Plantation

Article

Dec 2011

Forest visualization is a scientific, technical and efficient assistant tool for forest resources data management, forest management plan assesses and designs. Expending little time and investment but providing huge amount of benefits, forest visualization tools play a more increasingly important role in modern forest management, especially in China that has the largest plantation in the world. In this present paper, we reported a successful application of forest visualization of Pinus tabulaeformis Carr plantation using the outstanding stand visualization tool, Landscape Management System-Stand Visualization System (LMS-SVS) in Mulan-Weichang Forestry Administration of Hebei province, China. In addition, the outcomes of stand visual simulation were also analyzed and discussed. The study indicates that the LMS-SVS can provide direct, three-dimensional and elegant plan, profile and perspective views, and extensive statistical charts of the experimental P. tabulaeformis Carr plantation. In the fictitious forest environment, using freely individual tree marking, the LMS-SVS can design or modify the forest management plans, and simulates the whole forest management process for certain goals. As a conclusion, the LMS-SVS is an ideal tool for visual forest management and has broad prospects for a modern forestry in China. 1 INTRIDUCTION Forest is a complex and dynamic ecosystem provides a variety of benefits including water conservation, recreation, wildlife habitat, timber, foods and other forest products [1, 2]. However, these precious and vital natural resources are seriously threatened by natural disasters, environment pollutions, population bomb and improper utilization [3-6]. In order to achieve the supporting information for sustainable forest management, it is indispensable to simulate and forecast the dynamic changes of forest.

Linking Tools of Forest and Wildlife Managers: Wildlife Habitat Evaluation Using the Landscape Management System

Article

Full-text available

Jan 2002

Natural resource managers are increasingly being asked to consider values outside their fields. This is especially evident with regards to wildlife habitat changes caused by forest management activities. Forest managers are being asked to balance both wildlife habitat and forest product outputs from the forest. Our approach of implementing a Habitat Evaluation Procedure as a module of the Landscape Management System is an example of how forest growth and yield models can be integrated with existing wildlife models to expand the forest manager's tool set. The Landscape Management System uses the Forest Vegetation Simulator to simulate forest growth and changes caused by silvicultural activities on the Satsop Forest ownership, located in southwestern Washington State. The Habitat Evaluation Procedure module then calculates Habitat Suitability Indexes and Habitat Units for Cooper's hawk (Accipiter Cooperii), pileated woodpecker (Drycopus pileatus), southern red- backed vole (Clethrionomys gapperi), and spotted towhee (Pipilo erythrophthalmus) from the resulting projected forest inventories. The result is a tool that allows forest managers to assess changes in wildlife habitat caused by potential forest management at the stand and ownership levels. Because the Landscape Management System produces summaries of a variety of forest outputs, both tabular and visual, the results can then be used in analyses of existing and proposed forest management plans. On a stand-by-stand basis, multiple silvicultural pathways can be tested to assess which pathways meet varying desired habitat and forest product outputs. Through the use of stand and ownership level simulations and analyses of multiple target outputs, forest managers and decisionmakers are able to better understand output tradeoffs at the landscape and watershed levels. The public has become increasingly concerned over the past three decades about potential negative effects on wild- life caused by development and other modifications of wild- life habitat. Conversion of naturally regenerated forests to intensively managed plantations for timber production has raised concerns about habitat for species that are associated with these forest structures at the present time and in the future. While planning current and future forest manage- ment activities, forest managers are being asked to address how management will affect forest systems in the coming decades. As concern grows and more species are studied, many of these species become candidates for special consideration ranging from a "species of concern" at the State level, such as the pileated woodpecker (Dryocopus pileatus) in Wash- ington State, to "threatened" or "endangered," such as the northern spotted owl (Strix occidentalis caurina) in the Pacific Northwest, the red-cockaded woodpecker (Picoides borealis) in the Southeast, and the Kirtland's warbler (Dendroica kirtlandii) in the Lake States region, at both the State and Federal levels. Listing of these species resulted in regulatory constraints on forest management. Changes in Federal forest management in the Pacific Northwest under the Northwest Forest Plan to protect old forest habitat and the spotted owl exemplify the regulatory constraints. Har- vest on Pacific Northwest National Forests has virtually stopped. Technology has increased greatly during this time as well. Computing power has greatly increased, and forest growth and yield models, such as the Forest Vegetation Simulator (FVS), have been developed to predict forest growth and development though time. Using these tools, forest manag- ers can estimate potential harvest volumes and tree sizes in the future. From initial forest inventory data and simulated future data, managers create forest management plans based on criteria such as allowable harvest volume or stand structures, now and in the future, calculated from stand attributes such as tree species, sizes, and volumes. As demands on forests change, managers must estimate effects on other forest outputs such as wildlife habitat. Using a simulation system that includes wildlife habitat models, it may be possible for managers and other interested parties to gain insight into how current forest management may affect future forest outputs and ensure forests are managed in a sustainable manner. This study implements a Habitat Evaluation Procedure (HEP; USDI 1980a) within the Landscape Management System (LMS) for two reasons: first, to develop tools to support analysis of new management alternatives for Satsop Forest. Any analysis must be consistent with the original Satsop Forest HEP (Curt Leigh personal communication) to ensure comparable results. The original Satsop Forest HEP was performed on Satsop Forest, formerly the Satsop Nuclear Site, to assess losses of wildlife habitats caused by construc- tion of two nuclear power plants and to analyze management plans to mitigate for lost habitats. Second, because Habitat Suitability Index (HSI) models and the HEP use, primarily, tree-based measures, the HEP is used in this study to demonstrate linking wildlife habitat models with forest growth models within a forest simulation system.

Biophysical control of whole tree transpiration under an urban environment in Northern China

Article

May 2011
J HYDROL

Urban reforestation in China has led to increasing debate about the impact of urban trees and forests on water resources. Although transpiration is the largest water flux leaving terrestrial ecosystems, little is known regarding whole tree transpiration in urban environments. In this study, we quantified urban tree transpiration at various temporal scales and examined the biophysical control of the transpiration pattern under different water conditions to understand how trees survive in an urban environment. Concurrent with microclimate and soil moisture measurements, transpiration from C. edrus deodara(Roxb)Loud. ., Zelkova schneideriana Hend.-Mazz., Euonymus bungeanus Maxim., and Metasequoia glyptostroboides Hu et cheng was measured over a 2-year period using thermal dissipation probe (TDP) techniques. The average monthly transpiration rates reached 12.78 ± 0.73 (S.E.) mm, 1.79 ± 0.16. mm, 10.18 ± 0.55. mm and 19.28 ± 2.24. mm for C. deodara, Z.schneideriana, E. bungeanus and M. glyptostroboides, respectively. Transpiration rates from M. glyptostroboides reported here may need further study as this species showed much higher sap flows and greater transpiration fluctuation under different environmental conditions than other species. Because of deep soil moisture supply, summer dry spells did not reduce transpiration rates even when tree transpiration exceeded rainfall. While vapor pressure deficit (VPD) was the dominant environmental factor on transpiration, trees controlled canopy conductance effectively to limit transpiration in times of water stress. Our results provide evidence that urban trees could adopt strong physiological control over transpiration under high evaporative demands to avoid dehydration and can make use of water in deeper soil layers to survive summer dry spells. Moreover, urban trees have the ability to make the best use of precipitation when it is limited, and are sensitive to soil and air dryness.

Effect of spatial differentiation of Pinus massoniana canopy branches and leaves on rainfall interception – an example from Changting County

Article

Jun 2024

Mapping the vertical forest structure in a large subtropical region using airborne LiDAR data

Article

Oct 2023
ECOL INDIC

Tropical forests are mainly unstratified especially in Amazonia and regions with lower fertility or higher temperatures

Article

Full-text available

Jul 2023

The stratified nature of tropical forest structure had been noted by early explorers, but until recent use of satellite-based LiDAR (GEDI, or Global Ecosystems Dynamics Investigation LiDAR), it was not possible to quantify stratification across all tropical forests. Understanding stratification is important because by some estimates, a majority of the world’s species inhabit tropical forest canopies. Stratification can modify vertical microenvironment, and thus can affect a species’ susceptibility to anthropogenic climate change. Here we find that, based on analyzing each GEDI 25m diameter footprint in tropical forests (after screening for human impact), most footprints (60-90%) do not have multiple layers of vegetation. The most common forest structure has a minimum plant area index (PAI) at ~40m followed by an increase in PAI until ~15m followed by a decline in PAI to the ground layer (described hereafter as a one peak footprint). There are large geographic patterns to forest structure within the Amazon basin (ranging between 60-90% one peak) and between the Amazon (79 ± 9 % sd) and SE Asia or Africa (72 ± 14 % v 73 ±11 %). The number of canopy layers is significantly correlated with tree height (r2=0.12) and forest biomass (r2=0.14). Environmental variables such as maximum temperature (Tmax) (r2=0.05), vapor pressure deficit (VPD) (r2=0.03) and soil fertility proxies (e.g. total cation exchange capacity -r2=0.01) were also statistically significant but less strongly correlated given the complex and heterogeneous local structural to regional climatic interactions. Certain boundaries, like the Pebas Formation and Ecoregions, clearly delineate continental scale structural changes. More broadly, deviation from more ideal conditions (e.g. lower fertility or higher temperatures) leads to shorter, less stratified forests with lower biomass.

Evaluation of Quantitative Techniques for Managers using VIKOR Method

Article

Apr 2020

Gavade Deepak Murlidhar

Quantitative Techniques for Managers. Many different types of quantities, including numbers, symbols, and mathematical expressions, are used in quantitative management strategies. They support the decision-makers in choosing the best choice by serving as adjuncts. These are effective business methods that let managers maximize outcomes while working with constrained resources. Quantitative procedures are methods that give decision-makers organized, potent analytical tools based on quantitative data. Management uses this scientific approach to problem-solving and decision-making. The management can make decisions more effectively and objectively with the aid of quantitative methods. To arrive at a sound choice, such procedures rely on a scientific and statistical methodology. Quantitative procedures help the judgment and intuition of decision-makers by utilizing numerical symbols, mathematical expressions, and other quantities. These tools help businesses make better use of limited resources. One of the key benefits of quantitative data is that it is objective. There are fewer variables and more precise numbers used. This can help to eliminate study biases and increase the accuracy of the findings. Another benefit is that it is generally easier to obtain large sample sizes. The effective use of quantitative tools can assist the business in more accurately, affordably, and quickly resolving difficult issues. Managers can now use scientific management strategies to address complicated issues and boost productivity. To understand behavior and evaluate overall business performance, the financial modeling method known as quantitative analysis uses statistical modeling and data analysis. Quantitative analysts also referred to as quants, collect and evaluate information containing numerical values, such as salary and wage statistics. Quantitative techniques are a collection of programming and statistical methods that affect your decision-making, particularly in a field or line of work. It takes into account how symbols, mathematical phrases, and numbers are used. The VIKOR (VIšekriterijumsko Kompromisno Rangiranje) Optimal replacement Select method is used in Linear Programming, Network Models, Queuing Theory, Quality Control, Inventory Analysis, Production Scheduling Models, and Never, Hardly Ever, Sometimes, Frequently. Linear Programming, Network Models, Queuing Theory, Quality Control, Inventory Analysis, and Production Scheduling Models. Never, Hardly Ever, Sometimes, Frequently. Production Scheduling Models have the highest rank whereas Inventory Analysis has the lowest rank.

Contributions of the understory and midstory to total canopy solar-induced chlorophyll fluorescence in a ground-based study in conjunction with seasonal gross primary productivity in a cool-temperate deciduous broadleaf forest

Article

Jan 2023
REMOTE SENS ENVIRON

Solar-induced chlorophyll fluorescence (SIF) can represent gross primary productivity (GPP) in many types of terrestrial vegetation. In principle, the chlorophyll-a fluorescence signal responds to the amount of light absorption and the fraction of energy distribution in photosystems. Therefore, it is mechanistically linked with CO2 assimilation. Recently, radiative transfer models have traced the processes of emission, interception and reabsorption within a canopy in heterogeneous tree stands. These processes influence the expected relationship between SIF and GPP. We inferred that the vertical profile of SIF could reveal those processes. In addition, the sum of SIF emission from different pathways within the canopy must be equivalent to the total SIF emission from all leaves. The purposes of this study were: (1) to clarify the seasonal and diurnal variations of ground-based SIF observed above the overstory, midstory and understory layers (strata); (2) to examine whether the sum of SIF observed from the three layers could represent total SIF emissions, and (3) to examine whether SIF above the understory could reveal the photosynthetic activity within the vertical profile of a forest. To estimate how much SIF was present after its emission from leaves within the canopy, we conducted spectral radiation observations in three vertical layers: above the understory, midstory and overstory (8, 14 and 18 m from the ground, respectively) to retrieve the red and far-red SIF in a deciduous broadleaf forest ecosystem in Japan from April to November 2020. We found that SIF above the overstory and the sum of SIF from the three layers increased sharply at the leaf-onset of the overstory and was correlated with each season's GPP. The sum of far-red SIF from the three layers was proportional to the total SIF estimated using the escape ratio approach for SIF above the overstory. In this study we demonstrated that SIF above the understory could detect the increased photosynthesis of the understory in spring, compared with the GPP and the vertical profile of the CO2 concentrations. In summary, SIF observed in three forest layers detected the seasonal change of GPP within the canopy. Thus, a multi-layer approach can be used to understand the relationship between SIF and photosynthesis within the canopy.

Unstratified forests dominate the tropics especially in regions with lower fertility or higher temperatures

Preprint

Full-text available

Nov 2022

The stratified nature of tropical forest structure had been noted by early explorers, but until recent use of satellite-based LiDAR (GEDI, or Global Ecosystems Dynamics Investigation LiDAR), there has been no way to quantify stratification across all tropical forests. Understanding stratification is important because by some estimates, a majority of the world’s species inhabit tropical forest canopies. Stratification can modify vertical microenvironment, and thus can affect a species’ susceptibility to global warming. A better understanding of structure could also improve predictions of biomass across the tropics. Here we find that, based on analyzing each GEDI 25m diameter footprint in tropical forests (after screening for human impact), most footprints (60-90%) do not have multiple layers of vegetation. This result is highly scale dependent, but with a 25m footprint, the most common forest structure has a minimum plant area index (PAI) at ~40m followed by an increase in PAI until ~15m followed by a decline in PAI to the ground layer (described hereafter as a one peak footprint). However, there are large geographic patterns to forest structure within the Amazon basin (ranging between 60-90% one peak) and between the Amazon (79±9sd) and SE Asia or Africa (72±14 v 73±11). The number of canopy layers is significantly correlated with tree height (r2=0.12), forest biomass (r2=0.14), maximum temperature (Tmax) (r2=0.05), vapor pressure deficit (VPD) (r2=0.03) and soil fertility proxies (e.g. total cation exchange capacity -r2=0.01). Certain boundaries, like the Pebas Formation and Ecoregions, clearly delineate continental scale structural changes. More broadly, deviation from more ideal conditions (e.g. lower fertility or higher temperatures) leads to shorter, less stratified forests with lower biomass.

KERAGAMAN FLORISTIK DAN STATUS KETERANCAMAN KEPUNAHAN JENIS TUMBUHAN DI KAWASAN AIR TERJUN BUNBUN KABUPATEN MURUNG RAYA (Floristic Diversity and Extinction Threat Status of Plants at the Bunbun Waterfall Region, Murung Raya Regency): Setiarno

Article

Aug 2019

Admin JHT

This research is concerning the floristic diversity and status of extinction threat of class of plants at the Bunbun Waterfall region, Uut Murung sub Regency, Murung Raya Regency, Central Kalimantan Province. The purpose of this research was intended to find out the composition, diversity, and threat status of plants based on Government Regulation (PP) Nomor 7/1999 about Indonesia Scarce Plants and IUCN Global Red List. The research was using combination between the way of path and the way of blocked path. The research result showed that there are 42 kinds of trees, whereas six of which are assigned into critically endangered category of IUCN, like as gaharu (Aquilaria beccariana), keruing (Dipterocarpus cornutus), meranti kuning (Shorea macroptera), meranti merah (Shorea leprosula), meranti putih (Shorea lamellata) and ulin (Eusideroxylon zwageri). Shorea macroptera is assigned into endangered category, meanwhile Eusideroxylon zwageri and Aquilaria beccariana are assigned into vulnerable category based on IUCN. Shorea leprosula is a class which has the greatest essential value in whole growth stage, whereas Eugenia europholia, Shorea uliginosa and Shorea leprosula are dominant classes at each stage of growth. The index of tree diversity is classified into moderate category. Keywords: Floristic diversity, extinction threat status of plants, IUCN.

Desarrollo inicial de plantas de Mimosa scabrella bajo diferentes regímenes hídricos

Article

Full-text available

Jan 2019

One of the main abiotic factors that influence the growth and development of plants is water, and consequently the use of water stress-tolerant species increases the chances of success of crops in these conditions. The aim of this study was to evaluate the growth and initial development of Mimosa scabrella seedlings under different water regimes. Therefore, seeds were submitted to dormancy breaking and sowed in coir fiber substrate. After that, the seedlings were established in pots (8L capacity) containing composted pine bark substrate. The treatments consisted of five levels of pot capacity: 100 %, 75 %, 50 %, 25 % and 10 %. The experimental design was completely randomized with four replicates of five plants per treatment. There was influence of water regimes in most of the variables analyzed, where it was observed that with 50 % of pot capacity growth and development of plants showed satisfactory results. Moreover, the quality of the seedlings showed that in general, with only 25 % of the pot capacity plants have the ability to survive and settle under water stress conditions. Thus, the data indicate that Mimosa scabrella is a promising species for cultivation under water deficit, since the growth and initial development of seedlings occurred satisfactorily in conditions similar to these.

Patrones de distribución de alturas de bosques antiguos siempreverde del centro-sur de Chile

Article

Full-text available

Dec 2019

Tree height distributions in the canopy of old-growth temperate rainforests of south-central Chile SUMMARY Canopy structure is relevant to understanding forests functioning and sustaining biodiversity. In Chile, old-growth temperate evergreen rainforests have been characterized by a muti-stratified canopy; however, it is uncertain the common number of strata formed in the canopy or how dynamic processes structure the forest canopy. In this study, we evaluated two alternative hypotheses to explain canopy structure in old-growth temperate evergreen rainforests of Chile, i) the increased density of shade-tolerant tree species along the succession should lead to a non-stratified canopy, and ii) the occurrence of disturbances (e.g. individual tree falls opening gaps in the canopy) would allow species with different life strategies to concentrate at specific canopy heights, leading to stratified canopies. We tested these hypotheses in four old-growth stands, where we measured tree height distributions and the degree of correlation between vertical variables. We found two to three strata well defined strata in the canopy made up of species groups with similar functional traits. These results support the second hypothesis and suggest that the pattern of crown aggregation can be explained by the life strategies of the species, adapted to the occurrence of canopy openings. The dynamics of canopy gaps favors a stable canopy stratification in these forests along the succession. This relevant for the elaboration of sustainable management strategies and the conservation of the biodiversity of these ecosystems.

Efecto de la gradiente altitudinal sobre la composición florística, estructura y biomasa arbórea del bosque seco andino, Loja, Ecuador

Article

Full-text available

Dec 2019

Los bosques secos andinos son ecosistemas sensibles que se desarrollan en condiciones climáticas extremas y albergan alta riqueza de flora y fauna debido a la influencia de la cordillera de Los Andes. El objetivo de esta investigación fue analizar la influencia de la altitud en la composición florística, estructura y biomasa arbórea en el bosque seco andino. Se establecieron tres conglomerados a diferente altitud desde 1.750 m a 2.320 m s.n.m en el bosque seco andino de la Reserva Natural Pisaca, Loja. Fueron medidos los árboles con DAP ≥ 10 cm en parcelas de 0,36 ha; e individuos con DAP ≥ 5 cm en parcelas anidadas de 0,04 ha. Se calcularon parámetros ecológicos y dasométricos y fue estimada la biomasa mediante una ecuación alométrica generada para bosques tropicales secos. Se registraron 2.012 individuos, pertenecientes a 39 especies y un morfotipo distribuidos en 35 géneros y 23 familias. Las familias con mayor diversidad de especies fueron Asteraceae, Fabaceae y Myrtaceae. Las especies ecológicamente importantes fueron Myrcianthes sp., Lafoensia acuminata, Xylosma sp., Mauria heterophylla y Vachellia macracantha. La masa forestal presentó un área basal de 29,48 m2, volumen de madera de 149,51 m3 y biomasa total de 565,44 Mg ha-1. Se concluyó que, en el bosque seco andino conforme se incrementa la altitud aumenta la riqueza, estructura y la biomasa. Por tanto, la altitud es una variable topográfica relevante en los estudios sobre biodiversidad

Estimation on optical porosity or canopy closure for a forest stand with hemispherical images

Article

Oct 2005

Forest structure can not only influence the inhabited and biological factors in stands, but also determine the ecological functions of forest ecosystems. With the help of adjusting stand structure, reasonable forest management can come true. As one of the important indexes of forest structure, stand light transmission porosity or canopy closure can reflect the redistribution of light, water and other environmental factors entered the stand through forest canopy. It also plays a vital role on both forest management and many fine studies on forest ecology. Therefore, it is necessary to find a reasonable and accurate method to measure the light transmission porosity or canopy closure of a stand. This paper gave a detailed introduction on how to use hemispherical photograph to estimate canopy closure on the basis of the former related studies, and discussed in detail the selection of effective area of hemispherical photography, and some problems we have to pay attention to.

Simulating Landscape Change Using the Landscape Management System

Article

Dec 2009

This chapter describes the scientific basis for managing wildlife and other values across forested landscapes, and discusses the organization of the Landscape Management System (LMS) and how its modularity allows it to be improved and integrated with other systems. Managing landscapes can enhance their value to humans by providing appropriate habitats for desired wildlife species. The habitat management is an important determinant of wildlife presence and abundance in addition to hunter harvest of the target species, its prey, or its predators. The overall management system consists of two sets of tools: the Landscape Management System containing the LMS tool and the Decision Analysis System (DAS) Tools containing the "Scope & Group" and "Toggle" tools. The Landscape Management System coordinates the activities of approximately 50 computer programs to facilitate the evaluation of alternative management approaches. The LMS software package uses a point-and-click graphical user interface (GUI) with dropdown menus to interact with information for a specific landscape. A portfolio in LMS consists of a group of stands that are combined into a larger planning unit or landscape. Any user can create a portfolio by using minimal inventory and stand attribute information about individual stands or polygons. Menus within LMS facilitate the performance of functions such as growth, stand treatments, and visualization of stands, and landscapes.

Dynamics of canopy structure and understory light in montane evergreen broadleaved forest following a natural disturbance in North Guangdong

Article

Jan 2012

Natural disturbance is an important factor causing dynamic changes in forest canopies. An ice storm in southern China in 2008 was responsible for extensive damage to the forest ecosystem. The considerable distribution of canopy gaps created by the ice storm caused dynamic changes in the forest canopy. Therefore, studies to reveal the effects of the ice storm on forest regeneration and to monitor the restoration of damaged forest ecosystems will have significant implications for forestry research. Following the ice storm of 2008, a montane evergreen broad-leaved forest in Chebaling National Nature Reserve in northern Guangdong was investigated and a successive 3-year (2008-2010) community study of the 2 hm2 permanent plot was launched. We analyzed the changes in canopy structure (Canopy Openness and Leaf Area Index) and understory light (Transmitted Direct Solar Radiation, Transmitted Diffuse Solar Radiation and Transmitted Total Solar Radiation) in the forest following the ice storm using hemispherical photography to acquire canopy structure and understory light indexes. A quantitative study on the temporal and spatial variations in canopy structure and understory light as well as on environmental heterogeneity in the forest canopy is of considerable importance. Hemispherical photography is an example of optical remote sensing technology used to measure the parameters of canopy structure and understory light, and has now been widely recommended in the field of ecological research. The Kruskal-Wallis test (a non-parametric alternative to one- way ANOVA) and canonical correlation analysis were employed to analyze the changes in canopy structure and understory light. The main conclusions of this study are described in the following: 1) As the canopy openness shrank and the leaf area index increased, the understory light decreased in the forest during the recovery process following the ice storm; 2) A highly significant difference (P<0. 0001) was detected in canopy structure and understory light during the 3 years, but between-year differences showed a tendency to decrease as the forest recovered from 2008 to 2010; 3) In the first three years of forest recovery, transmitted direct solar radiation demonstrated a greater spatial-temporal fluctuation and provided a greater contribution to total solar radiation than did transmitted diffuse solar radiation; 4) Canopy openness was more sensitive than leaf area index as an indicator of canopy structure change, while canopy structure had a greater influence on transmitted diffuse solar radiation than transmitted direct solar radiation. Initially, the trees in the ice storm damaged forest grew rapidly during the recovery period following the storm, but the growth slowed down gradually and stabilized. There was a gradual reduction in the understory light as the forest closed due to tree growth. Canopy openness is better for the evaluation of the dynamic effects of canopy structure. The spatial and temporal variations of transmitted direct solar radiation were more complex than transmitted diffuse solar radiation. Therefore, research to study the effects of an ice storm on canopy structure of a subtropical forest to reveal dynamics of canopy structure and understory light, and to monitor the restoration of a damaged forest ecosystem, will have significant implications for both theoretical and applied forest restoration efforts.

Vertical Organization of Canopy Biota

Chapter

Full-text available

Sep 2004

David C. Shaw

The vertical organization of microclimate, structures, and biota in forests is a recurring theme in scientific investigations and forest description. One aspect of this is the concept of vertical stratification. Stratification proposes predictable vertical separation of canopy components such as forest leaves and other structures, species, or individual organisms into distinct horizons, layers, or gradients. Strict adherence to the proposition of stratification has been criticized as too limiting when in fact there are ecological gradients in three dimensions from forest floor through the canopy that are complex mosaics of biota, microclimate, gaps, and the growth, mortality, and development of trees. The definitions of stratification often vary with the user, and therefore lose some utility. The chapter includes a short review of the importance of forest composition, age, and structure, as well as microclimate on vertical organization of biota, and then describes general features of functional biotic groups and the primary factors that influence their vertical organization. It uses many examples from the Pacific Northwest of North America (PNW) and the Wind River Ganopy Grane Research Facility (WRCGRF), where intensive research on canopy ecology has been occurring in a tall stature, old-growth coniferous forest.

Review of forestry decision support system

Article

Full-text available

Mar 2010

With the rapid development of ecology and increased concern on environment and resources, forest management have shifted from single-target (such as timber production, ecological shelter, biodiversity conservation) traditional forest management to multi-target biodiversity-oriented forest management for sustainable ecology, economy and society. Given hierarchical complexities of forest system and multi-target forest management, forestry decision support system (DDS) has emerged as an important tool to determine management objectives, design scenarios, assess climate change and management plan. The core components of forest management DDS are habitat suitability and forest dynamics models used to assess the impact of management scenarios and climate change on forest functions, services and especially biodiversity conservation. In this paper, the development of forest dynamics and habitat suitability models are discussed, followed by a forestry DSS review with a particular focus on the current state and problems.

A forest structure model that determines crown layers and partitions growth and mortality rates for landscape-scale applications of tropical forests

Article

Mar 2012

1. We present a model to quantify tropical forest structure and explain variance in dynamic rates (growth and mortality) that is computationally simple and can be applied to landscape-scale forest inventory and, potentially, remote sensing-derived data. 2. The model is a modification of the perfect plasticity approximation (PPA) based on tree allometry, tree locations and sizes. The model quantifies crown area index (CAI) (number of crowns per unit ground area) and assigns trees to crown layers, which determines the expected number of crowns above each tree and thus its light environment. 3. The structural model, parameterized and tested for the Barro Colorado Island, Panama 50-ha forest dynamics plot using data from forest inventories and stereo aerial photographs, reproduces most canopy and understorey structural and dynamic properties. The PPA model worked as well or better than a computationally intensive, spatially explicit model. A single allometry for all trees worked equally well as functional group or species allometries. Models of growth and mortality were always improved by adding crown layers as defined by the PPA model. 4. The mean CAI of the 50-ha plot was 3.1 with low variance. The observed variance was lower than when tree locations were randomized, which drastically lowered the variance in tree density per plot, indicating that there are regulating forces towards a small range of crown area indices. 5. Synthesis. A number of simplifying characteristics in structure were uncovered with the PPA structural model applied to a tropical forest: species allometries were not needed despite the high species diversity in the forest; the model worked on a range of plot sizes; and the variance in CAI was surprisingly low, suggesting regulatory mechanisms. The PPA structural model can be used to develop a fully dynamic simulation model for tropical forests. The ability of the simulation model to predict temporal changes in landscape patterns of biomass, dynamic rates, and species and/or functional group composition will provide validation for the partitioning of dynamic rates by crown layers in the PPA structural model.

Forest Ecology and Conservation : A Handbook of Techniques

Book

May 2007

Adrian Christopher Newton

Forest conservation has become one of the most important environmental issues currently facing humanity, as a result of widespread deforestation and forest degradation. Pressures on remaining natural forests continue to intensify, leading to high rates of biodiversity loss. Understanding how human activities influence ecological processes within forests is essential for developing effective conservation action. This book describes research methods and techniques relevant to understanding forest ecology, with a particular focus on those that are relevant to practical conservation and sustainable forest management. This information is currently disparate and difficult to locate, and the intention here is to provide a comprehensive synthesis. Methods are presented for assessing forest extent and condition, structure and composition, and forest dynamics at a variety of scales. Techniques for assessing genetic variation and reproductive ecology, and for evaluating the habitat value of forests are also described. Particular emphasis is given to state-of-the-art techniques, such as remote sensing, GIS, computer modelling, and molecular markers. However, traditional methods of forest mensuration and ecological survey are also presented. The methods and techniques described are generally applicable to all forest types, including both temperate and tropical forest ecosystems.

Applied Linear Regression Models.

Article

Mar 1990

The Tropical Rain Forest

Article

Jul 1997

Principles of Animal Ecology

Article

Jan 1950

Ecological observations on the rain forest of Mount Dulit, Sarawak. Part I

Article

P.W. Richards

Ecological studies on the rain forest of southern Nigeria. I. The structure and floristic composition of the primary forest

Article

P.W. Richards

The vegetation of Moraballi Creek, British Guiana: An ecological study of a limited area of tropical rain forest

Article

Jan 1933

On the ecology of British beechwoods with special reference to their regeneration

Article

A.S. Watt

The development of northern red oak in mixed stands in central New England

Article

Chadwick Oliver

The Mora forests of Trinidad, British West Indies

Article

Jan 1946

J. S. P. Beard

Tropical Rain Forests of the Far East

Article

Jul 1977

Locating Strata in Tropical Rain Forests

Article

Jan 1954

I. V. Newman

Comparisons of Structure Among Mixed Dipterocarp Forests of North-Western Borneo

Article

Sep 1992

1. Relationships between lowland rain-forest structure, dynamics and site conditions were examined by the establishment of plots and profile diagrams within mature-phase forest at 13 sites and with permanent plots at three of these sites where trees have been enumerated over 20 years. 2. Most forest structural measures were intercorrelated but forest stature was uncorrelated with HCl-extractable soil nutrient concentrations and was apparently related to topography, soil depth and soil water. The relationship between diameter and height varied between forests and was correlated with HCl-extractable P and Mg for dry-land sites. 3. Tall forests generally had more slender canopy trees for a given height than short forests. Vertical stratification was associated with the presence and stand density of emergent trees, which comprise an architecturally and floristically distinct guild. Where emergents are scattered or absent, the main canopy and understorey were dense and no vertical stratification of crowns was perceptible; where emergents formed a continuous canopy, the main canopy was sparse, the understorey less dense and tree crowns were more separated into two horizontal strata. This type of forest appears to be confined to continuously moist soils on lower slopes, flat or undulating land. 4. Leaf size in the subcanopy was positively correlated with measured soil nutrients, and with the relationship between diameter and height. Among canopy trees it was not correlated with soil nutrients, nor with other aspects of forest structure. 5. Plots were originally established within mature phase, avoiding canopy gaps. Since establishment, gaps have accumulated within the permanent plots. Tree mortality was significantly clustered on clay soils, but not on sandy soils where windthrow was apparently less frequent and trees more often died standing. 6. Mean proportional diameter increments of large trees were not correlated with measured soil nutrients; but mean proportional diameter increments of recruits were correlated with measured soil nutrients. 7. A guild of tree species with the seed and/or seedling characteristics and the fast growth of pioneers, but with plagiotropic branching and crowns which reach the forest canopy or even emerge above it, was an important component of the building phase on soils with high mineral concentrations, but was sparsely distributed on other soils. 8. Standing volume and net volume increment were dominated by the mature phase; but soil nutrients probably influenced volume increment in the building phase. 9. Two inland forests, Bukit Mersing and Lambir, exhibited no net change in stand volume over 20 years. At Bako, a coastal forest on shallow freely draining soils, stand volume increased by 15.9% of the initial measurement. This increment occurred among trees of the largest diameter class while there was a net loss of volume in the small classes.

A Comparison of Montane and Lowland Rain Forest in Ecuador I. The Forest Structure, Physiognomy, and Floristics

Article

Nov 1963

A detailed study of montane and lowland forest areas at 1710 and 380 m respectively is presented; supporting data from three other lowland forests are also given. 1. The soils under the forests are compared. The montane is appreciably more acid in the A1 horizon, has a lower calcium-status, contains more organic matter, has a coarser texture and has freer drainage. 2. The forests are shown to be very similar in structure. The montane forest is somewhat less dense (Table 2), and the trees are of slightly lesser mean height and diameter (Table 3), but there is not much difference in the extent of the canopy holes. Concerning undergrowth plants (Table 4), the montane plot bore fewer saplings and poles (woody plants 3-9 ft, 9-20 ft) but far more cyclanths and palms. The data from the extra lowland plots indicate that the plot studied in detail was essentially typical of forest over a wide area in eastern Ecuador. 3. The stratification of forests is analysed more closely than by other workers and various types are distinguished. It is concluded that stratification of species has not been shown for any species-rich primary tropical lowland rain forest. Stratification of the heights of individuals and of canopy volume or mass is related to species-paucity and to the regeneration pattern. Other forms of stratification are briefly discussed. The montane forest shows no stratification of individuals or, over the whole plot, of canopy volume. No regular strata of individuals have been located in the four lowland forests (cf. Fig. 4). 4. Various evidence is used to show that all the forests investigated are either primary or very old secondary. 5. The leaf size spectra of the montane and lowland forests are similar but the montane has less macrophylls and more notophylls and microphylls. The montane forest has shorter buttresses, more leaning and distorted boles, and less monopodial crowns. 6. Both forests have strong floristic affinities (at the family level) with the Amazonian hylaea; the montane forest also contains a distinctly Andean element. 7. A revised system of synusiae of epiphytes and climbers is presented, together with a detailed analysis of the numbers of species and individuals in different taxonomic groups and arbitrary height classes in the two forest types. The montane forest has a greater abundance of skiophytic bryophytes, pteridophytes, bromeliads, and orchids and of photophytic bryophytes and macrolichens. The lowland forest has more photophytic dicotyledonous climbers and more climbing and epiphytic Araceae. 8. The classification of tropical rain forests is discussed and the three formation-types recognized by Richards (1952) are renamed Lowland Rain forest, Lower Montane Rain forest and Upper Montane Rain forest. The montane forest studied is assigned to the Lower Montane Rain forest formation-type and the lowland forests to the Lowland Rain forest formation-type. The limitations of a single system of formation-types for the whole of the tropics are emphasized.

An Analysis of Four Tropical Rain Forest Sites in New Guinea

Article

Mar 1970

K. Paijmans

Results are described of a detailed enumeration and comparison of four sample plots in tropical rain forest in New Guinea. The plots are 2 ac (0.8 ha) each in size and range in altitude from 1975 to 3700 ft (600-1125 m). Plots 1 and 2 are in forest on moderately steep hill slopes, and Plots 3 and 4 are on a gently sloping plateau surface, Plot 4 being on the break of slope towards a nearly level river terrace. Stratification of tree heights was studied by means of profile diagrams, height histograms, and graphs showing total crown width plotted against height class. With the exception of a dense layer of small trees between 15 and 25 ft (5-8 m) no clear evidence of layering was found. An examination of the accuracy of profile diagrams by comparison with measurements made during and after felling indicated considerable errors in the initial diagrams. Various structural features, notably tree density, girth distribution and buttressing, are correlated with topography and show a trend from the two hill forest Plots 1 and 2 to Plot 3 on the plateau surface proper thence to Plot 4 on the transition to river alluvium. Araucaria hunsteinii in Plot 2 seems an element additional to the mixed broad-leaved forest; it is responsible for the large number of trees in the highest height class, for the high average girth, and for a total basal area almost double that of broad-leaved forest alone. Excluding Araucaria from Plot 2 for the sake of comparison, Plot 4 has the highest average girth, and the lowest number of trees, while basal areas do not differ greatly between plots. The relationship between tree girth at breast height and crown width proved to be practically linear for crown diameters between 25 and 45 ft (7.5-13.5 m), and within this range crown diameters are from twenty-three to twenty-one times as large as bole diameters. With increasing tree height the frequency of cylindrical and conical crowns decreases, and that of round and flat crowns increases. The percentage of cylindrical and conical crowns is positively correlated with tree density. The number of species per 2 ac sample plot is above average for tropical lowland rain forest. Additive species/area curves show little sign of flattening out, and no `minimum area for adequate sampling' could be established. None of the plots shows family or species dominance, species diversity between plots is high, and so far as the data go the flora seems to vary continuously. Most species tested for group forming were found to be more or less randomly distributed, but instances of pattern occur in each plot.

Tropical Trees and Forests. An Architectural Analysis.

Article

Mar 1980

The Principles of Animal Ecology

Article

Aug 1950

Applied Linear Regression ModeIs

Article

Aug 1990

A method for quantifying vertical forest structure

Article

May 1998
FOREST ECOL MANAG

Vertical forest structure is an attribute of forests that is of interest to many disciplines and is consistently discussed in the context of ecosystem management. The vertical stratification of tree crowns is a forest attribute that influences both tree growth and understory community structure. Therefore, it should be considered when making management decisions that affect the structure of stands. However, current methods of quantifying vertical structure are either arbitrarily-defined and do not represent natural stratification patterns of stands or forests, or are too time consuming for landscape analyses. The program, TSTRAT, was developed to place trees into vertical strata in a structural classification of forest vegetation developed for the Inland Northwest (USA). The primary classification criteria were cover types and classes of stand development described by structural criteria. The TSTRAT algorithm defines strata on the basis of an assumption related to a competition cut-off point among tree crowns in a given area. The predicted strata assignments of trees closely approximated vertical strata that were visually identified, in addition to those identified through cluster analysis. TSTRAT assigns each tree to a stratum, produces various descriptive statistics by vertical stratum, and quantifies overstory tree species diversity and inequality of tree heights. Because TSTRAT simulates the natural vertical arrangement of tree crowns, it is potentially useful in identifying strata that are biologically-related to processes that determine natural vertical stratification patterns.

The Tropical Rain Forest

Article

Dec 1973

Paul W. Richards

Stratification of Temperature and Tropical Forests

Article

Sep 1973

Alan P. Smith

Past studies of forest structure have suggested that both plant and animal communities may be organized into several distinct vertical strata, the number of strata increasing with decreasing latitude. Hypotheses are proposed to explain the development of such strata. It is suggested that stratification may (1) optimize light utilization, (2) increase CO2 concentrations within the forest canopy, (3) increase pollination and dispersal rates, (4) reduce predation on flowers, fruit, and leaves, and (5) increase structural integrity of the forest. Causal explanations for stratification are also proposed.

Forest development in North America following major disturbances

Article

Dec 1980
FOREST ECOL MANAG

Chadwick Oliver

Large-scale, man-created or natural disturbances play a mjaor role in determining forest structure and species composition in many areas of North America and probably other temperate and tropical forests. Trees begin growth by a variety of mechanisms — each of which can respond to disturbances of a different severity. Studies suggest: a single group of species is not predestined to inhabit an area; forest physiognomic appearances assumed to imply all-aged succession often occur in single-age class stands; and recruitment of new stems into a forest often follows a disturbance rather than being a constant occurrence. After disturbances, forests develop through general physiognomic stages: “stand initiation”, “stem exclusion”, “understory reinitiation”, and “old growth”. Disturbance severity determines which species will dominate the forest afterward. The frequency of disturbances is also important in determining the general forest type over a large area, because species dominance and stand physiognomy change with time following disturbance.

On the Ecology of British Beechwoods with Special Reference to their Regeneration: part II, Sections II and III. The Development and Structure of Beech Communities on the Sussex Downs

Article

Jan 1925

A.S. Watt

The structure of natural Douglas-fir forests in Western Washington and Western Oregon.

Article

Jan 1988

L.C. Kuiper

Tropical Rain Forests of Far East

Article

Jan 1984

Timothy C. Whitmore

illus. 2. ed.

Architectural analysis of Douglas-fir forests.

Article

Jan 1994

L. C. (Leen C.) Kuiper

The architecture of natural and semi-natural Douglas-fir forest ecosystems in western Washington and western Oregon was analyzed by various case-studies, to yield vital information needed for the design of new silvicultural systems with a high level of biodiversity, intended for low-input sustainable forest management. In view of the discussions on the necessity of thinning in Douglas-fir plantations, thinning experiments in Germany and The Netherlands were analyzed by studying the distribution of various stemcrown- and increment parameters of individual trees, assigned to different social crown classes. Furthermore, the structural root system and the crown perimeter of 21 Douglas-fir trees were mapped to study relationships between root system structure and size, and stem and crown diameter and growing space, all of which relevant to tree stability. In the final chapter forty-three theorems are listed to discuss the hypotheses of the introductory chapter, and elements for the design of new silvicultural systems for Douglas-fir are presented.

A method for quantifying vertical forest structure A test of the accuracy of shade-tolerance classification based on physiognomic and reproductive traits Landscape Management User's Manual, version 1

Jan 1983
97

L C Kuiper
P A Latham
H R Zuuring
D W Coble
P J Baker
J L Moffett
S D Stinson
N Allison

Kuiper, L. C., 1994. Architectural analysis of Douglas-fir forests. Ph.D. thesis. Wageningen Agricultural University, Netherlands. Latham, P.A., Zuuring, H.R., Coble, D.W., 1998. A method for quantifying vertical forest structure. For. Ecol. Manage. 104, 157±170. Lorimer, C.G., 1983. A test of the accuracy of shade-tolerance classification based on physiognomic and reproductive traits. Can. J. Bot. 61, 1595±1598. McCarter, J.B., Wilson, J.S., Baker, P.J., Moffett, J.L., Stinson, S.D., Allison, N., 1996. Landscape Management User's Manual, version 1.5, Landscape Management Project, College of Forest Resources, University of Washington, Seattle, WA. pp. 97.

Wissenschaftliche Ergebnisse der zweiten deutschen Zentral-Afrika-Expeditioin 1910-1 unter Fuhrung Adolf Freidrichs

J Mildbraed

Mildbraed, J., 1922. Wissenschaftliche Ergebnisse der zweiten deutschen Zentral-Afrika-Expeditioin 1910-1 unter Fuhrung Adolf Freidrichs, Herzogs zu Mecklenburg. Klinkhardt and Biermann. Leipzig (cited in Richards, 1996).

Landscape Management User's Manual, version 1.5, Landscape Management Project

J B Mccarter
J S Wilson
P J Baker
J L Moffett
S D Stinson
N Allison

McCarter, J.B., Wilson, J.S., Baker, P.J., Moffett, J.L., Stinson, S.D., Allison, N., 1996. Landscape Management User's Manual, version 1.5, Landscape Management Project, College of Forest Resources, University of Washington, Seattle, WA. pp. 97.

Jan 1967

L R Holdridge

Holdridge, L.R., 1967. Life Zone Ecology. Tropical Science Center, San Jose, Costa Rica.

A quantitative technique for the identification of canopy stratification in tropical and temperate forests

Abstract

No full-text available

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