Forest Sciences Department, Universidade Federal Rural de Pernambuco, Paulista, Pernambuco, Brazil.
Forest Sciences Department, Universidade Federal Rural de Pernambuco, Recife, Pernambuco, Brazil.
Environ Monit Assess. 2019 Dec 16;192(1):47. doi: 10.1007/s10661-019-7955-5.
The present study aimed to estimate soil erosion in Machados County, Brazil. Rainfall erosivity was calculated using monthly and annual precipitation averages over a 30-year interval, soil erodibility was obtained with a granularity-based equation, and topography and land cover were obtained from DEM data and Sentinel - 2B imagery, respectively. A GIS interface was used to spatialize parameter results and for topography and land cover analysis. The achieved results allowed surmising that the soil loss for the study region risk is low, but significant, with a mean value of 8.11 t/ha year. About a quarter of the total area presented high soil loss, above 20 t/ha year. The biggest influential factors were soil erodibility, with a mean value of 0.028, and land cover, averaging 0.1409. The topographic factor averaged 3.414 and rain erosivity, found to be 2747.22 mm/year, is considered low for the region. Given a lack of conservative practices observed during field work, the soil stewarship P factor was considered 1 for the assessment. The use of orbital images to obtain C factor and the expression applied to calculate soil erodibility provided adequate results. In addition, there is a need for research to monitor and quantify erosion processes in Brazilian semiarid, as well as their erosion tolerance.
本研究旨在估算巴西马查多斯县的土壤侵蚀情况。降雨侵蚀力是通过 30 年间隔的月均和年均降水量计算得出的，土壤可蚀性则通过基于粒度的方程得出，地形和土地覆盖分别从 DEM 数据和 Sentinel-2B 图像中获取。GIS 界面用于空间化参数结果以及进行地形和土地覆盖分析。研究结果表明，研究区域的土壤流失风险较低，但仍很显著，平均每年流失 8.11 吨/公顷。约四分之一的总面积存在较高的土壤流失，超过 20 吨/公顷/年。最大的影响因素是土壤可蚀性，平均值为 0.028，其次是土地覆盖，平均值为 0.1409。地形因素平均值为 3.414，降雨侵蚀力为 2747.22 毫米/年，被认为是该地区较低的水平。考虑到实地工作中观察到缺乏保护措施，因此在评估中，将土壤管理 P 因子视为 1。利用轨道图像获取 C 因子和应用于计算土壤可蚀性的表达式提供了足够的结果。此外，还需要研究巴西半干旱地区的侵蚀过程及其侵蚀耐受性，并进行监测和量化。
