Investigating Relationships between Runoff–Erosion Processes and Land Use and Land Cover Using Remote Sensing Multiple Gridded Datasets

Abstract

Climate variability, land use and land cover changes (LULCC) have a considerable impact on runoff–erosion processes. This study analyzed the relationships between climate variability and spatiotemporal LULCC on runoff–erosion processes in different scenarios of land use and land cover (LULC) for the Almas River basin, located in the Cerrado biome in Brazil. Landsat images from 1991, 2006, and 2017 were used to analyze changes and the LULC scenarios. Two simulations based on the Soil and Water Assessment Tool (SWAT) were compared: (1) default application using the standard model database (SWATd), and (2) application using remote sensing multiple gridded datasets (albedo and leaf area index) downloaded using the Google Earth Engine (SWATrs). In addition, the SWAT model was applied to analyze the impacts of streamflow and erosion in two hypothetical scenarios of LULC. The first scenario was the optimistic scenario (OS), which represents the sustainable use and preservation of natural vegetation, emphasizing the recovery of permanent preservation areas close to watercourses, hilltops, and mountains, based on the Brazilian forest code. The second scenario was the pessimistic scenario (PS), which presents increased deforestation and expansion of farming activities. The results of the LULC changes show that between 1991 and 2017, the area occupied by agriculture and livestock increased by 75.38%. These results confirmed an increase in the sugarcane plantation and the number of cattle in the basin. The SWAT results showed that the difference between the simulated streamflow for the PS was 26.42%, compared with the OS. The sediment yield average estimation in the PS was 0.035 ton/ha/year, whereas in the OS, it was 0.025 ton/ha/year (i.e., a decrease of 21.88%). The results demonstrated that the basin has a greater predisposition for increased streamflow and sediment yield due to the LULC changes. In addition, measures to contain the increase in agriculture should be analyzed by regional managers to reduce soil erosion in this biome.

Dynamics of Sediment Transport in the Teles Pires River Basin in the Cerrado-Amazon, Brazil

“…We tried to classify the sediment production of each hydrographic sub-basin according to the classification described by Fonseca [7] which varies from very low (<0.0027 metric ton (t) per day (d −1 ) per km 2 ) to extremely high (>0.0548 t d −1 per km 2 ). Thus, sediment production in the Preto River is high, while in the Nandico and Renato Rivers (fluviometric stations 1 and 2) it is low, regardless of the water season of the year.…”

“…Q ss = 0.0864 * Q * C ss (7) where Q st is the total solid discharge in metric tons per day (t d −1 ), Q ss is the suspendedsolid discharge (t d −1 ), and Q se is the entrained solid discharge (t d −1 ) in Equation ( 5). For Equation ( 6), m is the total weight of the sample (metric tons or t), W is the width of the cross section (m), E sa is the efficiency of the sampler for 30% of the pouch = 1.0, n is the number of sampled verticals, l is the width of the sampler opening = 0.075 m, and t is the sampling time (minutes).…”

“…For Equation ( 6), m is the total weight of the sample (metric tons or t), W is the width of the cross section (m), E sa is the efficiency of the sampler for 30% of the pouch = 1.0, n is the number of sampled verticals, l is the width of the sampler opening = 0.075 m, and t is the sampling time (minutes). For Equation (7), Q is the total flow (m 3 s −1 ) and C ss is the concentration of suspended sediment (mg L −1 ). Four different types of samples of suspended sediment were evaluated.…”

“…The dynamics of sediment production and transport vary with the region's water seasonality. High intensity of precipitation associated with changes in land use cover enhance the capacity for erosion and sediment transport in more susceptible areas [7], with increasing urbanization, there is a reduction in water infiltration into the soil and an increase in net flow [8], affecting the quantity and quality of sediments transported in watercourses [7,8]. Thus, the sediment load produced in watersheds depends significantly on the amount of precipitated water and land use.…”

Assessing the Impacts of Future Land Use Land Cover and Climate Change on the Water Balance Components and Sediment Yield of The Bhavani Watershed in India

“…The SWAT model has been utilized globally in various river basins to examine how land use and climate, impact hydrological processes. Using this model, various researchers have studied the effects of land use and land cover changes on the runoff and sediment yield of river basins (da Fonseca et al, 2022;Defersha & Melesse, 2012;Gyawali et al, 2022;Samal & Gedam, 2021;Worku et al, 2017;Zhang et al, 2010). Land use and land cover (LULC) changes and climate change are two major factors that can significantly impact the hydrological flows of a watershed (Kim et al, 2013;M.…”