Soil loss due to water erosion in the Estibaná River sub-basin, Panama

Abstract

Introduction. Soil degradation develops naturally on a small scale, however, human intervention has accelerated and maximized it. Erosion is one of the main processes linked to degradation; this, combined with exploitation systems not adapted to the environment, is the basis for the reduction of productivity and pollution of water bodies. In Panama, soil degradation affects 20,787 km², an area that covers areas where much of the country's agricultural production is concentrated. Objective. To determine soil loss due to water erosion in the Estibaná River sub-basin through the implementation of erosion plots. Materials and methods. The research was carried out in the Estibaná River sub-basin, province of Los Santos, Azuero Peninsula, Panama (Arco Seco), during the rainy season (May – December) of the years 2020 and 2021. The methodology of erosion plots was used, using a Random Complete Block (BCA) design, in three locations, evaluating three treatments, with three repetitions, where total runoff, mass of transported sediments (suspended and precipitated), a Multifactorial ANOVA was performed. Results. Erosion was influenced by factors such as slope, soil cover and precipitation. It was determined that erosion amounted to 62.98 Mg/ha/year in bare soil on 10 % slopes, introducing living barriers and soil cover mitigated erosion damage, the behavior on other slopes presented a similar behavior. Conclusions. The variation of precipitation in frequency, intensity, duration; as well as anthropogenic interventions in the natural environment, are the main causes of the increase in soil loss within the Estibaná River sub-basin. The implementation of low-cost conservation efforts can mitigate the erosive effect of surface runoff.