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Erosion rates in residual limestone soils in a humid climate were measured for 10 years at one site, and for 4 years at another site, using erosion pins. Erosion pins were placed in gully floors and on convex divides between adjacent gullies, on abandoned land where vegetation had been removed. We measured an average erosion rate of 20 mm yr −1 ove...
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In 2016, a burial chamber hewn into limestone was discovered at Khirbet Aqabet Al Qadi on the north-western slope of Mount Ebal, two kilometres north of the city centre of Nablus. The floor of the chamber is 3.15 × 2.9m and the height averages 1.8m. A movable closure at the entrance consists of a limestone slab. The burial chamber houses four sarco...
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... The distance from the top of the pin to the soil surface on the downslope side of the pin was determined at the end of each growing season (Hart et al., 2017). Soil loss/accumulation was estimated as the difference between measured pin height and initial pin height (15 cm above the ground). ...
In hilly areas, agroforestry can be a more sustainable way of producing food and other products and services than agriculture based on sole-cropping. However, research is needed to evaluate and quantify formation of natural terraces in agroforestry and their contribution to soil conservation. This study quantified natural terrace formation and examined its role in reducing soil and nutrient losses during early stages of agroforestry with fruit trees, contour grass strips and maize or coffee in agroforestry systems on sloping land in northwest Vietnam. Two agroforestry systems, comprising longan (Dimocarpus longan L.)-mango (Mangifera indica L.)-maize (Zea mays L.)-guinea grass (Panicum maximum Jacq.) (fruit-maize-AF) and son tra (Docynia indica (Wall.) Decne.)-coffee (Coffea arabica L.)-guinea grass (fruit-coffee-AF) were compared with sole-cropped maize (sole-maize) and sole-cropped coffee (sole-coffee), respectively. Terrace formation was evaluated over five years using erosion pins placed above grass strips and the volume of terrace formed was estimated. Soil and nutrient losses were quantified using soil traps. The results showed that terraces formed as the systems developed, through gradual deposition of soil sediment above the living grass strips and trees. Accumulated soil sedimentation above the grass strips during the five-year study period raised the soil surface by 4.0 cm in fruit-maize-AF and 4.2 cm in fruit-coffee-AF, and the volume of terraces generated by the grass strips was 0.26 and 0.43 m³/m respectively. The fruit-maize-AF and fruit-coffee-AF systems significantly reduced losses of soil, soil organic carbon (SOC) and associated nutrients (N, P, K) compared with sole-maize and sole-coffee already in the first two years, while the reductions were greater from year 3 onwards. On average across experiments and years, the agroforestry systems reduced soil, SOC, N, P and K losses by 27–76%, 21–78%, 20–82%, 24–82% and 22–84%, respectively. These findings show that agroforestry with fruit trees, grass strips and crops could be a useful management practice and viable option for sustainable agricultural systems on sloping land, by reducing soil (and carbon and nutrient) losses through terrace formation.
... The runoff collection method was applied from June 2020 to March 2021, and erosion pins were applied from August 2021 to April 2022. Previous studies have traditionally only used one of these methods [2,16,62], but we found them to be complimentary to obtain both the spatial distribution of erosion and deposition and the total settlement yield. ...
... Despite the issues with establishment, the overall erosion rates observed in this study were within the limit of 2-7 mm/yr. This is much lower than a previous study conducted on a completely bare steep slope which had erosion rates of 20 mm/yr [62]. This study, which was conducted over a 10-year period, also recommended longer monitoring duration than was possible in the current study for erosion pins. ...
Shallow slope failures due to erosion are common occurrences along roadways. The use of deep-rooted vegetative covers is a potential solution to stabilize newly constructed slopes or repair shallow landslides. This study compared species that may provide slope stabilization for sites in the Piedmont region of the southeastern USA. Six species were tested on experimental plots under natural rainfall conditions, and vegetation health and establishment were monitored. Two methods were used to measure surface erosion, measurement of total suspended solids in collected runoff and erosion pins. While measurement uncertainty was high for both methods, differences were evident between species in the spatial distribution of surface erosion that was related to the quality of vegetation establishment. For three species that established well, soil cores were collected to measure root biomass at depths up to 40 cm. Vetiver grass (Vetiveria zizaniodies) had substantially higher mean root biomass (3.75 kg/m3) than juniper shrubs (Juniperus chinensis; 0.45 kg/m3) and fescue grass (Lolium arundinaceum; 1.28 kg/m3), with the most pronounced difference in the deepest soil layers. Seeding with turf grass such as fescue is a common practice for erosion control in the region but replacing this with vetiver on steep slopes may help prevent shallow landslides due to the additional root reinforcement. Additional work is needed to measure the magnitude of the strength gain.
... Nas encostas os pinos podem servir para medir os efeitos da erosão laminar, ou estimar taxas erosivas nas paredes de voçorocas. Esta última é uma abordagem semelhante à sua aplicação em margens de rios (IRELAND et al., 1939;WOLMAN, 1959;LAWLER, 1993;GUERRA, 2005;LOUREIRO, 2013;HART et al., 2017;JUGIE et al., 2018;KEARNEY et al., 2018;MYERS et al., 2019;GUERRA et al., 2020). ...
... Os pinos de erosão foram aplicados, pioneiramente, por Ireland et al. (1939), para mensurar o recuo das paredes de voçorocas RICHTER et al., 2020). Contudo, para alguns autores (BOARDMAN & FAVIS-MORTLOCK, 2016;HART et al., 2017;GHOLAMI et al., 2021), sua origem viria dos trabalhos de Schumm e de Colbert, ambos datados de 1956. A partir destes, Haigh (1977) e Wolman (1959) disseminaram duas abordagens: (1) pinos inseridos verticalmente no solo de encostas e voçorocas e (2) inseridos horizontalmente em margens de rios. ...
... Nesse contexto, os métodos foram amplamente utilizados, ao longo das décadas, através das seguintes abordagens: (a) estacas nas bordas de ravinas e voçorocas (BEZERRA, 2011;LEAL & RODRIGUES, 2011;LOUREIRO, 2013;LISBOA et al., 2017;FRANCISCO, 2018), pinos de erosão monitorando; (b) a erosão laminar na superfície das encostas (HAIGH, 1978;DE PLOEY & GABRIELS, 1980;GUERRA, 2005;HANCOCK & LOWRY, 2015;ANTONLI & THOMAZ, 2016;HART et al., 2017;KEARNEY et al., 2018); e, (c) a erosão fluvial nas margens de rios (WOLMAN, 1959;LAWLER, 1993;CUNHA, 1996;JUGIE et al., 2018;CASTRO et al., 2019;MYERS et al., 2019). Para esta última aplicação, Lawler (1991) apresentou os pinos de erosão foto-eletrônicos (photo-electronic erosion pins -PEEPs). ...
Resumo: Experimentos têm papel fundamental na Geomorfologia, que utiliza desde técnicas de
mensuração, monitoramentos, observações de campo, de laboratório e uso de recursos
cartográficos, como cartas topográficas e fotografias aéreas, até novas tecnologias, cada vez mais
precisas, fáceis e rápidas na aquisição e processamento de dados. Assim, monitorar a erosão
hídrica dos solos é, continuamente, tema relevante. Pensar que o tema se esgotou é equivocado,
pois muitas lacunas demandam respostas, como: melhorar a compreensão das interações entre
fenômenos naturais e antrópicos, do espaço-tempo de processos e taxas erosivas, e o
desenvolvimento de técnicas e estratégias inovadoras, que visem sua redução, prevenção e
mitigação. Diversos autores têm exposto formas de comparar e avaliar técnicas antigas e atuais.
Nesse sentido, o capítulo revisa a literatura brasileira sobre métodos de monitoramento, dos
convencionais aos digitais. Aborda o estado da arte no âmbito de parcelas, estacas e pinos de
erosão; sensoriamento remoto, através de imagens aéreas, de satélites e suas resoluções espaciais,
e modelos digitais diversos, como obtidos por LiDAR. Entende-se, pois, cada técnica como
relevante e complementares entre si.
Palavras-Chave: Erosão Laminar; Erosão Linear; Parcelas de Erosão; Pinos de Erosão; LiDAR;
Geotêxteis.
Abstract: Experiments play a fundamental role in Geomorphology. Multiple field and laboratory
techniques are used. These include measurement techniques, monitoring, field and laboratory
observations, and cartographic resources (e.g. topographic maps and aerial photographs).
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Together with new technologies, the techniques enable the rapid acquisition and processing of
expanding amounts of increasingly accurate data. As a geomorphological process, monitoring
hydric erosion is crucial and many important questions remain. These include improving our
understanding of interactions between natural and anthropogenic phenomena, space-time
relationships, erosion processes and rates, scale issues and the development of innovative
techniques. The technologies have applied dimensions, including strategies to prevent, decrease
and mitigate the effects of hydric erosion. Many authors have discussed different ways to compare
and assess both old and modern techniques. Therefore, this chapter reviews the Brazilian literature
on monitoring methods, ranging from conventional techniques to modern advances in digital
technology. The chapter addresses the current state-of-the-art, including the use of erosion pins
and plots, remote sensing, satellite imagery, aerial images, digital models, and LiDAR techniques.
The chapter discusses the potential of each individual technique and the synergistic potential of
using multiple complementary techniques.
Key words: Sheet Erosion; Linear Erosion; Erosion Plots; Erosion Pins; LiDAR; Geotextiles.
... The studies concluded that different morphological settings within a gully respond differently to rainfall-driven and wind-driven erosion. Recent research in middle Tennessee's Highland Rim physiographic province, on a site with similar, clay-rich soils, concluded that erosion rates differed for interfluves (26 mm/year) and channels (14 mm/year), and that frost action, rain splash, and dry ravel were driving processes for erosion, varying seasonally [34]. ...
... This suggests that, while overall erosion occurred at the same rate over the long-term, different processes drive erosion in interfluves and sidewalls. Sheet flow and rain-splash erosion are likely drivers of erosion in interfluves under humid subtropical climate conditions [34]. ...
... Hart et al.'s 2017 study [34] of erosion in similar clay-rich soils and a humid subtropical climate produced similar erosion rates of 14 mm/year in gullies and 26 mm/year in interfluves, which is also similar to an average erosion rate of 15 mm/year observed in the badlands of New Jersey, USA [34]. Similar to our results, the same study also found that gully interfluves eroded more than channels. ...
Gullies are significant contributors of sediment to streams in the southeastern USA. This study investigated gully erosion in the clay-rich soils of east Tennessee under a humid subtropical climate. The aims of this study were to (1) estimate long-term erosion rates for different gully geomorphic settings, (2) compare patterns of erosion for the different settings, and (3) model the response of gully erosion to freeze-thaw events. Erosion was measured weekly from June 2012 to August 2018 using 105 erosion pins distributed in gully channels, interfluves, and sidewalls. Erosion rates were estimated from average slopes of lines of best fit of pin lengths versus time. Maximum and minimum temperature was calculated daily using an on-site weather station and freeze-thaw events were identified. Gully erosion was modeled using antecedent freeze-thaw activity for the three geomorphic settings. Long-term erosion rates in channels, interfluves, and sidewalls were 2.5 mm/year, 20 mm/year, and 21 mm/year, respectively; however, week-by-week erosion was statistically different between the three settings, indicating different erosive drivers. Models of erosion with lagged freeze-thaw variables explained up to 34.8% of the variability in erosion variables; sidewall erosion was most highly related to freeze-thaw activity. Freeze-thaw in prior weeks was an important variable in all erosion models.
Erosion pins are considered a simple and inexpensive way to estimate soil losses due to erosion and have been used in different environments with different degrees and types of erosion. Despite the advantages of this technique, there is a shortage of studies that demonstrate how data systematization and soil loss calculations are performed using this technique. Therefore, this study aimed to present the step-by-step data systematization process of erosion pins obtained in the field and the calculation of soil losses, with the measurement of soil losses under the effect of hydrogel. Readings from 16 pins installed in an area cultivated with soursop trees planted on contour lines and associated with stone rows were monitored weekly between 19/02 and 19/03/2022 by measuring the distance between the soil surface and the end of each pin. The readings were organized by pin and date of measurement. Subsequently, soil lowering and burial, soil density, useful area of each pin, and soil loss in kg/m3 and Mg/ha-1 were determined, enabling statistical analysis and technical interpretation of the data.
