SENSORIAMENTO REMOTO TEMPORAL DA CAPACIDADE DE SUPORTE DE CARGA DE SOLOS SOB DIFERENTES TIPOS DE USO, COBERTURA E DECLIVIDADE NA BACIA DO RIO PRETO, OESTE BAIANO

Abstract

The pre-consolidation pressure (σp) is considered as an indicator of the load-bearing capacity (LBC) that a soil can tolerate in terms of surface pressures, especially from agricultural traffic. The objective of this work was to perform remote temporal sensing of the load carrying capacity of soils in the River Black Basin, Western Bahia, under different types of use, coverage and slope. Scenes from the LANDSAT 8 (OLI) satellite were used to classify land use and land cover by means of supervised classification and load bearing capacity prediction models available in the specialized literature for Brazilian soils, depending on the clay content (platform SoilInfo) and soil moisture through the Soil Moisture Active Passive - SMAP satellite, considering a time frame from 2016 to 2019, monthly. The LBC estimates for each class of use and coverage and slope were calculated at 95% confidence intervals for statistical comparisons. There was a variation of LBC both between months and between years, pointing to an inverse trend of LBC in relation to humidity, in which the highest values were obtained in the dry period in relation to the rainy season, indicating the influence of the region's seasonality. The annual crops / livestock reached high values of LBC in the year 2017 and may be related to the intensified use of agricultural machinery, adoption of soil management systems and trampling of large animals. As for the levels of slope, flat areas, between 0 and 8%, were the most exposed to processes of physical changes due to the low values when compared to the other slope classes. It is concluded that the LBC varies over time and inversely when referring to humidity. The classes of use and coverage of BHRP presented average values of 221.71 kPa for annual crops / livestock; 219.74 kPa for rural / pasture formations and 218.86 kPa for forest / savanna formations. Over the years there was a general decrease in LBC in the studied classes Cap (4.08%), Fcp (0.38%) and Ffs (1.40%). Slope increases promote an increase in LBC in the basin, of the order of 1.06 kPa for each 1% slope.