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| Microclimate heterogeneity across a human-modified tropical forest landscape. Red hues denote warmer and drier microclimates, while blue ones depict cooler and more humid habitats. Figure inserts relate to Case studies 1-3 in the main text. They highlight examples of how microclimatic variation across this disturbance gradient can influence population dynamics of disease vectors (left), interactions among trophic groups such as those between tree seedlings, termites and fungi (middle), as well as shaping the community composition of functionally important groups such as dung beetles (right).
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Logging and habitat fragmentation impact tropical forest ecosystems in numerous ways, perhaps the most striking of which is by altering the temperature, humidity, and light environment of the forest—its microclimate. Because local-scale microclimatic conditions directly influence the physiology, demography and behavior of most species, many of the...
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Context 1
... what elements of microclimate shape insect vector life history is therefore critical to predicting population dynamics and developing vector control strategies. In field experiments spanning three years, Gregory et al. (2019) found that changes in temperature driven by tropical forest conversion to oil palm plantations dramatically altered larval development rates in the mosquito Aedes albopictus, which is the vector of dengue and chikungunya viruses (Figure 3). However, this response was mediated by the El Niño Southern Oscillation (ENSO) event of 2015-16. ...
Context 2
... conditions related to solar radiation, air temperature, vapor pressure deficit, and soil moisture all play a direct role in modulating plant ecophysiology and metabolism (Ashton and Gunatilleke, 1995;Will et al., 2013). But they can also affect seedling survival and growth indirectly, by altering competitive, facilitative, and mutualistic interactions with other species (Figure 3). For instance, mycorrhizal fungi can promote seedling growth and survival by increasing access to soil nutrients and moisture, and by conferring resistance to pests and pathogens (Brunner et al., 2015;Corrales et al., 2018). ...
Context 3
... combining these data with existing high-resolution microclimate maps of understorey temperature and vapor pressure deficit , dung beetle abundance and community composition can be extrapolated across the oil palm-forest mosaic landscape. In this way one can explore how changes in the diversity and trait composition of dung beetle communities associated with microclimate gradients impact soil nutrient cycling across human-modified tropical landscapes (Figure 3). This research would add to the growing body of literature exploring whether biodiversity loss driven by land-use change leads to a collapse in ecosystem functioning, or if instead relatively species-poor communities of disturbance-resistant species are able to maintain high levels of ecosystem functioning (Slade et al., 2017Tuma et al., 2019). ...
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Tropical ecosystems are undergoing unprecedented rates of degradation from deforestation, fire, and drought disturbances. The collective effects of these disturbances threaten to shift large portions of tropical ecosystems such as Amazon forests into savanna-like structure via tree loss, functional changes, and the emergence of fire (savannization)...
Citations
... Evaporative cooling is an important process in creating fine-scale environmental heterogeneity thus forming relatively cool and humid microenvironments in various habitat types from sandy shores (Davis and Keppel, 2021) through exposed talus habitats (Varner and Dearing, 2014) to closed forests (Jucker et al., 2020;von Arx et al., 2012). These specific conditions support the ontogeny, survival and foraging of several invertebrate and vertebrate organisms (such as centipedes and amphibians in the tropics or pikas in North American mountaneous regions). ...
... These specific conditions support the ontogeny, survival and foraging of several invertebrate and vertebrate organisms (such as centipedes and amphibians in the tropics or pikas in North American mountaneous regions). Water-holding capacity or moisture availability of microhabitats gain increasing attention recently as an important attribute of buffering capacity of forests against temperature extremes (Davis et al., 2019;Greiser et al., 2024;Jucker et al., 2020). ...
The relevance of forests in mitigating biodiversity loss and the negative effects of climate change on the biota is largely shaped by below-canopy microclimatic conditions, which are buffered, cooler and more humid compared to adjoining open habitats. Water-filled tree holes (dendrotelms, DTs) are special tree-related microhabitats that host semi-aquatic communities and are important substrates or water sources for numerous taxa (e.g., birds, mammals, insects, fungi, bryophytes). Despite their microrefugia-role might be more pronounced under climate change-induced drought events, little is known about their microclimate and its potential drivers.
In an abandoned Turkey oak-dominated coppice stand in Hungary, the microclimates of 80 paired dendrotelms and adjacent forest plots were measured in the summer of 2021. Compared to nearby open areas, under closed forests, air temperature maxima were up to 5 °C cooler, DTs had an additional negative offset of 2.5 °C and increased air humidity by 15 percentage points (5% vs. 20 %). The local microclimate of DTs and the adjacent closed forest differed significantly in means and extremes of air temperature, relative humidity and vapour pressure deficit, which was mainly driven by DT entrance area and water volume and seemed independent from local stand structure. On the contrary, nearby below-canopy microclimate was shaped by the distance from forest edge, incoming light and tree density. Water volume in DTs also influenced local forest microclimates up to 0.5–1 m from the entrances.
As the frequency and severity of extreme weather events such as heatwaves are likely to intensify due to climate change, the importance of microhabitats and habitat trees for invertebrates and vertebrates will increase further, and will additionally contribute to the microclimatic refugia role of forests. Active protection of veteran trees under the scheme of continuous cover forestry or conservation-oriented management is essential facing climate change to mitigate its negative effects on forest biodiversity.
... Although microclimate has been of long-standing interest in ecology, earlier studies had limited scope as they were based on field measurements at single point locations [24][25][26] . Recent advances in remote sensing, big-data processing, and the growing availability of ready-to-use fine-resolution remote sensing datasets have created a renewed interest in microclimate ecology 9,27,28 . By employing these advanced techniques, ecologists are gaining new insights into the processes underlying microclimate variability at continental scale and postulating the consequences on forest habitats in nexus with changing climate 14,18,29 . ...
Temperature is a fundamental driver of species distribution and ecosystem functioning. Yet, our knowledge of the microclimatic conditions experienced by organisms inside tropical forests remains limited. This is because ecological studies often rely on coarse-gridded temperature estimates representing the conditions at 2 m height in an open-air environment (i.e., macroclimate). In this study, we present a high-resolution pantropical estimate of near-ground (15 cm above the surface) temperatures inside forests. We quantify diurnal and seasonal variability, thus revealing both spatial and temporal microclimate patterns. We find that on average, understory near-ground temperatures are 1.6 °C cooler than the open-air temperatures. The diurnal temperature range is on average 1.7 °C lower inside the forests, in comparison to open-air conditions. More importantly, we demonstrate a substantial spatial variability in the microclimate characteristics of tropical forests. This variability is regulated by a combination of large-scale climate conditions, vegetation structure and topography, and hence could not be captured by existing macroclimate grids. Our results thus contribute to quantifying the actual thermal ranges experienced by organisms inside tropical forests and provide new insights into how these limits may be affected by climate change and ecosystem disturbances.
... The steep environmental gradients that characterise the upper and lower vegetation layers of tropical forests are a key factor determining species diversity and abundance [1][2][3][4][5]. In arthropods, particular species are consistently found in some vertical strata while being less common in others due to variation in abiotic conditions, behaviour, and the distribution of resources [6,7]. ...
Vertical gradients in microclimate, resource availability and interspecific interactions are thought to underly stratification patterns in tropical insect communities. However, only a few studies have explored the adaptive significance of vertical space use during the early stages of reproductive isolation. We analysed flight-height variation across speciation events in Heliconius butterflies representing parallel colonisations of high-altitude forest. We measured flight-height in wild H. erato venus and H. chestertonii, parapatric lowland and mountain specialists respectively, and found that H. chestertonii consistently flies at a lower height. By comparing our data to previously published results for the ecologically equivalent H. e. cyrbia (lowland) and H. himera (high-altitude), we found that the species flying closest to the ground are those that recently colonised high-altitude forests. We show that these repeated trends largely result from shared patterns of ecological selection producing parallel trait-shifts in H. himera and H. chestertonii. Although our results imply a signature of local adaptation, we did not find an association between resource distribution and flight-height in H. e. venus and H. chestertonii. We discuss how this pattern may be explained by variation in forest structure and microclimate. Overall, our findings underscore the importance of behavioural adjustments during early divergence mediated by altitude-shifts.
... In the absence of successful regeneration from seed, sprouting may represent a prevalent persistence mode in the natural regrowth of disturbed forests in Borneo. Furthermore, extreme post-logging microclimate caused by canopy opening (Jucker et al., 2020) and unfavourable soil conditions due to compaction during timber extraction (Hattori et al., 2013) may both inhibit the survival and growth of seedlings. In contrast, resprouting trees may benefit from resources stored in their remaining parts, established root systems giving them access to nutrients and water below the compacted soil layer, and higher light associated with a more open canopy. ...
... serious indirect impacts of logging. Unlogged small SST most probably died either due to collateral damage to the residual stand during harvest (Pinard and Putz, 1996) or because of unfavourable post-logging environmental conditions such as disturbed soil (Hattori et al., 2013) and altered microclimate resulting from the open canopies (Blonder et al., 2018;Jucker et al., 2020). Both soil compaction and extreme microclimate can hinder the survival and regrowth of seedlings for several decades after logging (Hattori et al., 2013;Jucker et al., 2020), which, together with the absence of seed trees and a seed bank (Ashton, 1982), could explain the failure of SST to increase their densities in logged plots. ...
... Unlogged small SST most probably died either due to collateral damage to the residual stand during harvest (Pinard and Putz, 1996) or because of unfavourable post-logging environmental conditions such as disturbed soil (Hattori et al., 2013) and altered microclimate resulting from the open canopies (Blonder et al., 2018;Jucker et al., 2020). Both soil compaction and extreme microclimate can hinder the survival and regrowth of seedlings for several decades after logging (Hattori et al., 2013;Jucker et al., 2020), which, together with the absence of seed trees and a seed bank (Ashton, 1982), could explain the failure of SST to increase their densities in logged plots. In contrast to SST, MST were able to persist even through the most intensive logging disturbances, thus minimizing the impact of selective logging on the residual tree community by reducing the population turnover. ...
... Habitat degradation and land-use change has been shown to decrease the availability of cooler microclimates and hence the temperature buffering potential of a habitat (Jucker et al., 2020). As conversion of land for agricultural use continues to accelerate and global temperatures rise, the protection of pristine habitats for their temperature buffering potential may become increasingly important. ...
Climate change is a major threat to species worldwide, yet it remains uncertain whether tropical or temperate species are more vulnerable to changing temperatures. To further our understanding of this, we used a standardised field protocol to (1) study the buffering ability (ability to regulate body temperature relative to surrounding air temperature) of neotropical (Panama) and temperate (the United Kingdom, Czech Republic and Austria) butterflies at the assemblage and family level, (2) determine if any differences in buffering ability were driven by morphological characteristics and (3) used ecologically relevant temperature measurements to investigate how butterflies use microclimates and behaviour to thermoregulate. We hypothesised that temperate butterflies would be better at buffering than neotropical butterflies as temperate species naturally experience a wider range of temperatures than their tropical counterparts. Contrary to our hypothesis, at the assemblage level, neotropical species (especially Nymphalidae) were better at buffering than temperate species, driven primarily by neotropical individuals cooling themselves more at higher air temperatures. Morphology was the main driver of differences in buffering ability between neotropical and temperate species as opposed to the thermal environment butterflies experienced. Temperate butterflies used postural thermoregulation to raise their body temperature more than neotropical butterflies, probably as an adaptation to temperate climates, but the selection of microclimates did not differ between regions. Our findings demonstrate that butterfly species have unique thermoregulatory strategies driven by behaviour and morphology, and that neotropical species are not likely to be more inherently vulnerable to warming than temperate species.
... Thereby, increasing evapotranspiration (ET) and vagaries in the microclimate of the area being investigated. Also, the opening and withdrawing the canopy are the most pervasive impact upon logging as it rises solar radiation and air flow within under storey and the drop of evapotranspiration leading to an alteration of the forest's microclimate (Hardwick et al., 2015;Jucker et al., 2020;Senior et al., 2018). Table 4 to the year 2018 (Table 2), forested area is predicted to suffer a reductionby 36.1%, ...
Nigeria obtains high rate of deforestation with a loss of about 60 percent of its primary forests
between 2000 and 2005 as a result of logging, subsistence agriculture,wood exploitation, and
urban expansion.This research assessed the level of deforestation and how it has affected
Ilorin’s microclimate and the environments. The specific objectives of this study were
assessing the relationship that occurs between deforestation and microclimate, examining
deforestation and the impact it has within the study area of microclimate, and forecasting the
microclimate within the study area by the year 2030. The statistical tools engaged were both
descriptive (mean, frequency distribution table and, bar charts) and inferential statistics
(multiple regression analysis). The research indicated that there isnansignificantmrelationship
betweenmdeforestationmwithmr
2mvariables ofm0.888 formmaximum temperature,m0.201 for
minimummtemperature,m0.997 formprecipitation,m0.43 formsolarmoutput,m-0.797 andm -
0.873 for evapotranspiration and relative humidity respectively and Ilorin’s microclimate.
The study concludes that deforestation greatly influences the microclimate of Ilorin and
occurs due to human’s anthropogenic activities. Deforestation has also led to climate change.
Keywords: Deforestation; Climate; Micro-climate; Vegetation Cover
... This research bridges the gap created and contributes to the existing research by employing super-efficiency DEA, Malmquist index, and SFA methodologies for analysis. Furthermore, the embodiment of forest ecology is vital for the growth and functioning of the forest ecosystem, controlling the microclimate and water balance, and providing habitats for organisms [57]. Within a forest ecosystem, forest ecology helps establish the science of how organisms interact with the environment. ...
Forestry is the underpinning of economic and environmental civilization for sustainable economic development. Forestry benefits ecosystems and local dwellings; thus, transforming and advancing forest products in a civilized society is critical to building a progressive community. This research aims to analyze the merits of forest products based on static, dynamic, and scale efficiency. It employed the super-efficient data envelopment analysis—Charnes, Cooper and Rhodes, and Malmquist index methods with an enhanced robustness check by applying the Stochastic Frontier Analysis. The results show that, first, from the perspective of static efficiency, the forestry industry’s operating performance is maintained at a relatively high level, with a minimal fluctuation range; however, the scale efficiency is observed at a deficient level. Limited by the scale efficiency results, the aggregate comprehensive technical efficiency was at a low standard. The average total factor productivity of dynamic efficiency for each company reached 1.029, indicating that the resource allocation of listed companies is relatively reasonable, operating efficiency is on the rise, and technical level changes are a substantial source of total factor productivity growth. Furthermore, the super efficiency DEA findings indicated that 11 of the most high-performance companies attained an efficiency value above criterion value one after re-ranking. The comprehensive efficiency value of Sun Paper reached 1.438 in 2019, Sophia 1.393, Hexing Packaging 1.383, Fujian Jinsen 1.326, Bunny 1.271, Meike Home Furnishing 1.235, Jingxing Paper 1.222, Zhongshun Jiezou 1.116, Meiying Sen 1.099, Chenming Paper 1.064, Da Ya Dekor 1.015. Second, the comprehensive efficiency value of Fujian Jinsen’s company has a more significant impact on the overall average efficiency of the forestry listed companies. After excluding Fujian Jinsen, the average comprehensive efficiency of 2018–2019 indicated an upward trend for the listed companies. This study suggests that policymakers should strengthen the forestry industry development plan and policy implementation regulations to focus on the forward-looking and guiding principles of industrial and technological innovation policies.
... In this context, the growing availability and accessibility of active remote-sensing tools such as unmanned aerial vehicle laser scanning (UAV-LS) provides opportunities to study how environmental variation and fragmentation shape forest structure and function Ordway & Asner, 2020). Combining laser scanningderived fine-scale three-dimensional data on forest physical structure with field data on different ecosystem properties including biodiversity, function and micro-habitat has brought new insights on tropical forest functioning and potential responses to environmental changes (Chadwick et al., 2020;De Frenne et al., 2021;Jucker et al., 2020;Molina et al., 2016). Thus, UAV-LS offers relevant options to unveil and decipher the multifaceted influence of edge on tropical forest and unlocks possibilities to predict and upscale the influence of edges over large scales and with better accuracy than classical landscape metrics. ...
Widespread forest loss and fragmentation dramatically increases the proportion of forest areas located close to edges. Although detrimental, the precise extent and mechanisms by which edge proximity impacts remnant forests remain to be ascertained.
By combining unmanned aerial vehicle laser scanning (UAV‐LS) with field data from 46 plots distributed at varying distances from the edge to the forest interior in a fragmented forest of New‐Caledonia, we investigated edge influence on forest structure, composition, function, above‐ground biomass (AGB) and microclimate. Using simple linear regressions, structural equation modelling and variance partitioning, we analysed the direct and indirect relationships between distance to edge, UAV‐LS‐derived canopy structural metrics, understorey microclimate, AGB, taxonomic and functional composition while accounting for the potential influence of fine‐scale variation in topography.
We found that the distance to the closest forest edge was strongly correlated with canopy structure and that canopy structure was better correlated to forest composition, function, biomass and microclimate than distance to the closest forest edge. This suggests that the influence of edge is mediated by changes in canopy structure. Plots located near the edge exhibited a lower canopy with more gaps, higher microclimate extremes, lower biomass, lower taxonomic and functional diversity as well as denser wood and lower specific leaf area. UAV‐LS‐derived canopy structural metrics were relevant predictors of understorey microclimate, biomass and taxonomic and functional composition. Overall, the influence of topography was marginal compared to edge effects.
Synthesis. Accounting for fine‐scale variation in canopy structure captured by UAV‐LS provides insights on the multiple edge impacts on key forest properties related to structure, diversity, function, biomass and microenvironmental conditions. Integrating UAV‐LS‐derived data can foster our understanding of cascading and interacting impacts of anthropogenic influence on tropical forest ecosystems and should help to improve conservation strategies and landscape management policies.
... Other successional changes relate to structural complexity such as biomass, canopy height, and gap frequency, which increase with older forest age (de Almeida et al., 2020;Kent et al., 2015). Forest recovery also results in changes in biological interactions, such as more complex foodwebs (Estes et al., 2011;Fraser et al., 2015;Jucker et al., 2020). ...
Microhabitat differentiation of species communities such as vertical stratification in tropical forests contributes to species coexistence and thus biodiversity. However, little is known about how the extent of stratification changes during forest recovery and influences community reassembly. Environmental filtering determines community reassembly in time (succession) and in space (stratification), hence functional and phylogenetic composition of species communities are highly dynamic. It is poorly understood if and how these two concurrent filters—forest recovery and stratification—interact.
In a tropical forest chronosequence in Ecuador spanning 34 years of natural recovery, we investigated the recovery trajectory of ant communities in three overlapping strata (ground, leaf litter, lower tree trunk) by quantifying 13 traits, as well as the functional and phylogenetic diversity of the ants. We expected that functional and phylogenetic diversity would increase with recovery time and that each ant community within each stratum would show a distinct functional reassembly. We predicted that traits related to ant diet would show divergent trajectories reflecting an increase in niche differentiation with recovery time. On the other hand, traits related to the abiotic environment were predicted to show convergent trajectories due to a more similar microclimate across strata with increasing recovery age.
Most of the functional traits and the phylogenetic diversity of the ants were clearly stratified, confirming previous findings. However, neither functional nor phylogenetic diversity increased with recovery time. Community‐weighted trait means had complex relationships to recovery time and the majority were shaped by a statistical interaction between recovery time and stratum, confirming our expectations. However, most trait trajectories converged among strata with increasing recovery time regardless of whether they were related to ant diet or environmental conditions.
We confirm the hypothesized interaction among environmental filters during the functional reassembly in tropical forests. Communities in individual strata respond differently to recovery, and possible filter mechanisms likely arise from both abiotic (e.g. microclimate) and biotic (e.g. diet) conditions. Since vertical stratification is prevalent across animal and plant taxa, our results highlight the importance of stratum‐specific analysis in dynamic ecosystems and may generalize beyond ants.
... Tropical forests in particular demonstrate the greatest diversity and vertical complexity of all terrestrial systems (Terborgh, 1985;Denslow, 1987;Johnson, 1998), and they have formed the basis for much vertical stratification research (Kays & Allison, 2001;Ozanne et al., 2003). The complex three-dimensional structure of a forest creates vertical gradients in abiotic conditions such as wind, light, humidity, and temperature (Allee et al., 1949;Terborgh, 1985;Campbell & Norman, 2012;Jucker et al., 2020), which have a strong influence on patterns of diversity. For example, in a mesic Panamanian forest, thermal variance over 24 h was on average 5 C in the canopy, 3 C in the understorey, and 1 C in the soil (Basham & Scheffers, 2020). ...
Tropical forests harbour the highest levels of terrestrial biodiversity and represent some of the most complex ecosystems on Earth, with a significant portion of this diversity above ground. Although the vertical dimension is a central aspect of the ecology of forest communities, there is little consensus as to prominence, evenness, and consistency of community‐level stratification from ground to canopy. Here, we gather the results of 62 studies across the tropics to synthesise and assess broad patterns of vertical stratification of abundance and richness in vertebrates, the best studied taxonomic group for which results have not been collated previously. Our review of the literature yielded sufficient data for bats, small mammals, birds and amphibians. We show that variation in the stratification of abundance and richness exists within and among all taxa considered. Bat richness stratification was variable among studies, although bat abundance was weighted towards the canopy. Both bird richness and abundance stratification were variable, with no overriding pattern. On the contrary, both amphibians and small mammals showed consistent patterns of decline in abundance and richness towards the canopy. We descriptively characterise research trends in drivers of stratification cited or investigated within studies, finding local habitat structure and food distribution/foraging to be the most commonly attributed drivers. Further, we analyse the influence of macroecological variables on stratification patterns, finding latitude and elevation to be key predictors of bird stratification in particular. Prominent differences among taxa are likely due to taxon‐specific interactions with local drivers such as vertical habitat structure, food distribution, and vertical climate gradients, which may vary considerably across macroecological gradients such as elevation and biogeographic realm. Our study showcases the complexity with which animal communities organise within tropical forest ecosystems, while demonstrating the canopy as a critical niche space for tropical vertebrates, thereby highlighting the inherent vulnerability of tropical vertebrate communities to forest loss and canopy disturbance. We recognise that analyses were constrained due to variation in study designs and methods which produced a variety of abundance and richness metrics recorded across different arrangements of vertical strata. We therefore suggest the application of best practices for data reporting and highlight the significant effort required to fill research gaps in terms of under‐sampled regions, taxa, and environments.
