34 / 2023-12-23 08:52:56

Soil Erosion and Sediment Yield Spatiotemporal Modeling in Tucutunemo River Basin, Venezuela

soil erosion,sediment yield,temporal modeling,river basin

In this paper, it is presented the soil erosion and sediment yield spatio-temporal modeling in the Tucutunemo river basin, Venezuela, for the months of 2015. USLE and Langebein-Schumm models were adapted to the products of remote sensing such as Landsat satellite images and ASTER global digital elevation model of 30 meters-spatial resolution. Monthly precipitation was modeled using statistical spatial prediction models based on Ordinary Krigging from records of 23 precipitation gauges. Precipitations of 30 minutes during dry season were lower than 35 mm corresponding to a type of precipitation that caused a dry condition of soil while precipitation in rainy season varied between 35 and 50 mm, leaving a moderately high moisture in soil. Precipitation events greater than 50 mm occurred with lower frequency, three events were recorded in months of July, August and October for 2015. The erodibility factor (K) was greater in  inceptisols with respect to mollisols. Slope length (L) factor was defined using a field slope length of 100 m, which was one dimension associated to the average length of the furrows in the agricultural plots. Slope steepness (S) influenced negative or positive sign as an indicator of the direction of the water runoff on terrain. Direction change was significant in mountains area of Tucutunemo river basin. The crop management factor (C) and conservation practice (P) were dependent of land use and land cover. The soil erosion and sediment yield in the Tucutunemo river basin reach high values toward the high and middle part of the basin reducing the magnitude toward the low part. In addition, the magnitudes of the soil erosion and sediment yield were influenced by the dry and rainy seasons. The Tucutunemo river basin is a rural area where the main LULC are agricultural activities, vegetation and degraded soil. Agricultural activities were developed in the middle part of basin. By this study, it was found that the soil erosion and yield sediment occurred in the high and middle part of basin. According the location, precipitation of 30 minutes occurred in a magnitude from high moderately to high during rainy season. Precipitation caused the greatest amount of soil erosion and sediment yield in the high and middle part of the basin where the soil was inceptisols type, while these phenomenons were lower in the low part of basin where the mollisols was soil type, which was cohesive soil because of the clay contents.