Predicting the impact of land-use changes on soil erosion rates in the three small sub-catchments of Larona Catchment

Abstract. Road and railway infrastructure increased in the Mediterranean region during the last three decades. This included the building of embankments, which are assumed to be a~large source of sediments and runoff. However, little is known about soil erosion rates, the factors that control them, and the processes that contribute to detachment, transport and deposition of sediments from road and railway embankments. The objective of this study was therefore to assess the impacts of road and railway embankments as a source of sediment and water, and compare them to other land use types (citrus plantations and shrublands) representative of the Cànyoles watershed to evaluate the importance of road embankments as a~source of water and sediment under high magnitude low frequency rainfall events. Sixty rainfall experiments (1 m2 plots; 60 min duration; 78 mm h−1 rainfall intensity) were carried out on these land use types: 20 on two railway embankments (10 + 10), 20 on two road embankments (10 + 10), and 10 on citrus and 10 on shrubland. Road and railway embankments were characterized by bare soils with low organic matter and high bulk density. Erosion processes were more active in road, railway and citrus plots, and null in the shrublands. The non-sustainable soil erosion rates of 3 Mg ha−1 y−1 measured on the road embankments were due to the efficient runoff connectivity plus low infiltration rates within the plot as the runoff took less than one minute to reach the runoff outlet. Road and railway embankments are both an active source of sediments and runoff, and soil erosion control strategies must be applied. The citrus plantations also act as a~source of water and sediments (1.5 Mg ha−1 y−1), while shrublands are sediment sinks, as no overland flow was observed due to the high infiltration rates.

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Deforestation effects on soil erosion rates and soil physicochemical properties in Iran: a case study of using fallout radionuclides in a Chernobyl contaminated area

10.5194/soil-2021-2 ◽

2021 ◽

Author(s):

Maral Khodadadi ◽

Christine Alewell ◽

Mohammad Mirzaei ◽

Ehssan Ehssan-Malahat ◽

Farrokh Asadzadeh ◽

...

Keyword(s):

Soil Erosion ◽

Physicochemical Properties ◽

Land Use Changes ◽

Aggregate Stability ◽

Soil Physicochemical Properties ◽

Sediment Delivery ◽

Erosion Rates ◽

Fallout Radionuclides ◽

Soil Erosion Rates ◽

The Impact

Abstract. Deforestation for farming and grazing purposes has become a global challenge. To study the impact of deforestation on soil erosion rates and soil physicochemical properties, Zarivar Lake watershed, Kurdestan Province, Iran, was selected. Converting the steep hillslopes naturally under oak forest to rainfed vineyards has been one of the most common land-use changes in the area. We used 137Cs and 210Pbex radionuclides and quantified the Chernobyl-derived 137Cs fallout with 239+240Pu. The soil samples were collected from two adjacent and similar hillslopes, one of which is under natural forest, while the other is under rainfed vineyard. Using 137Cs/239+240Pu rates and a simple unmixing of the 137Cs sources indicated that 50.2 ± 10.0 % of 137Cs was Chernobyl-derived. The mean reference inventory values of 137Cs, 210Pbex, and 239+240Pu were estimated to be at 6152 ± 1266, 6079 ± 1511, and 135 ± 31 Bq m−2, respectively. At the forested hillslope, net soil erosion rates based on 137Cs, and 210Pbex, techniques were estimated to be at 5.0 and 5.9 Mg ha−1 yr−1, respectively, resulting in Sediment Delivery Ratios (SDRs) of 96 and 70 %. However, at the vineyard hillslope, the net soil redistribution rates were at 25.9 and 32.5 Mg ha−1 yr−1 for 137Cs and 210Pbex, respectively, resulting in respective SDRs of around 95 and 92 %. Both 137Cs and 210Pbex indicated that as a result of deforestation, soil erosion has increased by approximately five times. Percolation Stabilities (PS) in forest and vineyard topsoil are about 309 and 160 gr H2O 600 s−1 classified as rapid and moderate PSs, respectively. Rapid PS in forest soil implies high aggregate stability, whereas moderate PS in vineyard soils indicates that they are generally weakly-structured. All in all, the results of the present study revealed that deforestation and converting natural vegetation to cropland prompted soil loss and deteriorated physicochemical properties of the soil.

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Impacts of oak deforestation and rainfed cultivation on soil redistribution processes across hillslopes using 137Cs techniques

Forest Ecosystems ◽

10.1186/s40663-021-00311-1 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Shamsollah Ayoubi ◽

Nafiseh Sadeghi ◽

Farideh Abbaszadeh Afshar ◽

Mohammad Reza Abdi ◽

Mojtaba Zeraatpisheh ◽

...

Keyword(s):

Land Use ◽

Magnetic Susceptibility ◽

Soil Erosion ◽

Erosion Rate ◽

Land Use Changes ◽

Soil Samples ◽

Natural Forest ◽

Oak Forests ◽

Erosion Rates ◽

Rainfed Farming

Abstract Background As one of the main components of land-use change, deforestation is considered the greatest threat to global environmental diversity with possible irreversible environmental consequences. Specifically, one example could be the impacts of land-use changes from oak forests into agricultural ecosystems, which may have detrimental impacts on soil mobilization across hillslopes. However, to date, scarce studies are assessing these impacts at different slope positions and soil depths, shedding light on key geomorphological processes. Methods In this research, the Caesium-137 (137Cs) technique was applied to evaluate soil redistribution and soil erosion rates due to the effects of these above-mentioned land-use changes. To achieve this goal, we select a representative area in the Lordegan district, central Iran. 137Cs depth distribution profiles were established in four different hillslope positions after converting natural oak forests to rainfed farming. In each hillslope, soil samples from three depths (0–10, 10–20, and 20–50 cm) and in four different slope positions (summit, shoulder, backslope, and footslope) were taken in three transects of about 20 m away from each other. The activity of 137Cs was determined in all the soil samples (72 soil samples) by a gamma spectrometer. In addition, some physicochemical properties and the magnetic susceptibility (MS) of soil samples were measured. Results Erosion rates reached 51.1 t·ha− 1·yr− 1 in rainfed farming, whereas in the natural forest, the erosion rate was 9.3 t·ha− 1·yr− 1. Magnetic susceptibility was considerably lower in the cultivated land (χhf = 43.5 × 10− 8 m3·kg− 1) than in the natural forest (χhf = 55.1 × 10− 8 m3·kg− 1). The lower soil erosion rate in the natural forest land indicated significantly higher MS in all landform positions except at the summit one, compared to that in the rainfed farming land. The shoulder and summit positions were the most erodible hillslope positions in the natural forest and rainfed farming, respectively. Conclusions We concluded that land-use change and hillslope positions played a key role in eroding the surface soils in this area. Moreover, land management can influence soil erosion intensity and may both mitigate and amplify soil loss.

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Evaluation of changes in soil erosion rates in Andalucia between 1990 and 2018

10.5194/egusphere-egu2020-863 ◽

2020 ◽

Author(s):

Filippo Milazzo ◽

Tom Vanwalleghem ◽

Pilar Fernández, Rebollo ◽

Jesus Fernández-Habas

Keyword(s):

Land Use ◽

Soil Erosion ◽

Land Management ◽

Aerial Photographs ◽

Frequency Distributions ◽

Erosion Rates ◽

Soil Erosion Rate ◽

Soil Erosion Rates ◽

Management Changes ◽

Soil Erosion By Water

<p>Land use and land management changes impact significantly on soil erosion rates. The Mediterranean, and in particular Southern Spain, has been affected by important shifts in the last decades. This area is currently identified as a hotspot for soil erosion by water. In the effort to achieve the SDG Target 15, we aim to show the effect of land management change, assessing soil erosion rate based on historical data. We analyzed the evolution of land use from historical aerial photographs between 1990 and 2018. We then calculated soil erosion with RUSLE. For this, we first determined the distribution frequency of cover-management factors for each land use class, comparing current land use maps with the European Soil Erosion Map (Panagos et al., 2015). Past C factors where then assigned using a Monte Carlo approach, based on the obtained frequency distributions.&#160;</p>

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LAND USE: U.S. Soil Erosion Rates--Myth and Reality

Science ◽

10.1126/science.289.5477.248 ◽

2000 ◽

Vol 289 (5477) ◽

pp. 248-250 ◽

Cited By ~ 204

Author(s):

S. W. Trimble

Keyword(s):

Land Use ◽

Soil Erosion ◽

Erosion Rates ◽

Soil Erosion Rates

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Influence of bare soil and cultivated land use types upstream of a bank gully on soil erosion rates and energy consumption for different gully erosion zones in the dry-hot valley region, Southwest China

Natural Hazards ◽

10.1007/s11069-015-1722-x ◽

2015 ◽

Vol 79 (S1) ◽

pp. 183-202 ◽

Cited By ~ 10

Author(s):

Zhengan Su ◽

Donghong Xiong ◽

Yifan Dong ◽

Dan Yang ◽

Su Zhang ◽

...

Keyword(s):

Land Use ◽

Energy Consumption ◽

Soil Erosion ◽

Southwest China ◽

Bare Soil ◽

Gully Erosion ◽

Cultivated Land ◽

Erosion Rates ◽

Land Use Types ◽

Soil Erosion Rates

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Investigation of the effect of anthropogenic land use on the Pănăzii Lake (Romania) catchment area using Cs-137 and Pb-210 radionuclides

PLoS ONE ◽

10.1371/journal.pone.0251603 ◽

2021 ◽

Vol 16 (6) ◽

pp. e0251603

Author(s):

Robert-Csaba Begy ◽

Codrin F. Savin ◽

Szabolcs Kelemen ◽

Daniel Veres ◽

Octavian-Liviu Muntean ◽

...

Keyword(s):

Land Use ◽

Soil Erosion ◽

Sedimentation Rate ◽

Catchment Area ◽

Gamma Spectroscopy ◽

Soil Parameters ◽

Erosion Rates ◽

Soil Erosion Rate ◽

Soil Erosion Rates ◽

Lake Catchment

The problem of soil degradation has accentuated over recent decades. Aspects related to soil erosion and its relation to changes in land use as well as anthropogenic influence constitute a topic of great interest. The current study is focused on a soil erosion assessment in relation to land use activities in the Pănăzii Lake catchment area. Fallout radionuclides were used to provide information on soil erosion as well as redistribution rates and patterns. Variations in the sedimentation rate of the lake were also investigated as these reflect periods in which massive erosion events occurred in the lake catchment area. The novelty of this study is the construction of a timescale with regard to the soil erosion events to better understand the relationship between soil erosion and land use activities. In this study, 10 soil profiles and one sediment core from the lake were taken. Soil parameters were determined for each sample. The activities of 210Pb, 137Cs and 226Ra were measured by gamma spectroscopy. For low 210Pb activities, measurements via 210Po using an alpha spectrometer were performed. Soil erosion rates were determined by the 137Cs method and the sedimentation rate calculated by the Constant Rate of Supply (CRS) model. A soil erosion rate of 13.5 t·ha-1·yr-1 was obtained. Three distinct periods could be observed in the evolution of the sedimentation rate. For the first period, between 1880 and 1958, the average deposition rate was 9.2 tons/year, followed by a high deposition period (1960–1991) of 29.6 tons/year and a third period, consisting of the last 30 years, during which the sedimentation rate was 15.7 tons/year. These sedimentation rates fluctuated depending on the main land use activity, which can also be seen in the soil erosion rates that had almost doubled by the time agricultural activities were performed in the area.

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Soil aggregation, erodibility, and erosion rates in mountain soils (NW Alps, Italy)

Solid Earth ◽

10.5194/se-6-403-2015 ◽

2015 ◽

Vol 6 (2) ◽

pp. 403-414 ◽

Cited By ~ 41

Author(s):

S. Stanchi ◽

G. Falsone ◽

E. Bonifacio

Keyword(s):

Land Use ◽

Soil Erosion ◽

Agricultural Land ◽

Statistical Tests ◽

Protective Action ◽

Aggregate Stability ◽

Soil Aggregation ◽

Soil Erodibility ◽

Erosion Rates ◽

Soil Erosion Rates

Abstract. Erosion is a relevant soil degradation factor in mountain agrosilvopastoral ecosystems that can be enhanced by the abandonment of agricultural land and pastures left to natural evolution. The on-site and off-site consequences of soil erosion at the catchment and landscape scale are particularly relevant and may affect settlements at the interface with mountain ecosystems. RUSLE (Revised Universal Soil Loss Equation) estimates of soil erosion consider, among others, the soil erodibility factor (K), which depends on properties involved in structure and aggregation. A relationship between soil erodibility and aggregation should therefore be expected. However, erosion may limit the development of soil structure; hence aggregates should not only be related to erodibility but also partially mirror soil erosion rates. The aim of the research was to evaluate the agreement between aggregate stability and erosion-related variables and to discuss the possible reasons for discrepancies in the two kinds of land use considered (forest and pasture). Topsoil horizons were sampled in a mountain catchment under two vegetation covers (pasture vs. forest) and analyzed for total organic carbon, total extractable carbon, pH, and texture. Soil erodibility was computed, RUSLE erosion rate was estimated, and aggregate stability was determined by wet sieving. Aggregation and RUSLE-related parameters for the two vegetation covers were investigated through statistical tests such as ANOVA, correlation, and regression. Soil erodibility was in agreement with the aggregate stability parameters; i.e., the most erodible soils in terms of K values also displayed weaker aggregation. Despite this general observation, when estimating K from aggregate losses the ANOVA conducted on the regression residuals showed land-use-dependent trends (negative average residuals for forest soils, positive for pastures). Therefore, soil aggregation seemed to mirror the actual topsoil conditions better than soil erodibility. Several hypotheses for this behavior were discussed. A relevant effect of the physical protection of the organic matter by the aggregates that cannot be considered in $K$ computation was finally hypothesized in the case of pastures, while in forests soil erodibility seemed to keep trace of past erosion and depletion of finer particles. A good relationship between RUSLE soil erosion rates and aggregate stability occurred in pastures, while no relationship was visible in forests. Therefore, soil aggregation seemed to capture aspects of actual vulnerability that are not visible through the erodibility estimate. Considering the relevance and extension of agrosilvopastoral ecosystems partly left to natural colonization, further studies on litter and humus protective action might improve the understanding of the relationship among erosion, erodibility, and structure.

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