SPATIAL UNCERTAINTY OF NUTRIENT LOSS BY EROSION IN SUGARCANE HARVESTING SCENARIOS

Made available in DSpace on 2018-11-27T02:12:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-07-01. Added 1 bitstream(s) on 2019-10-09T18:28:01Z : No. of bitstreams: 1 S0100-06832015000401181.pdf: 1293648 bytes, checksum: 3c130ec3c20f617f9174bff9d0424567 (MD5) The assessment of spatial uncertainty in the prediction of nutrient losses by erosion associated with landscape models is an important tool for soil conservation planning. The purpose of this study was to evaluate the spatial and local uncertainty in predicting depletion rates of soil nutrients (P, K, Ca, and Mg) by soil erosion from green and burnt sugarcane harvesting scenarios, using sequential Gaussian simulation (SGS). A regular grid with equidistant intervals of 50 m (626 points) was established in the 200-ha study area, in Tabapua, Sao Paulo, Brazil. The rate of soil depletion (SD) was calculated from the relation between the nutrient concentration in the sediments and the chemical properties in the original soil for all grid points. The data were subjected to descriptive statistical and geostatistical analysis. The mean SD rate for all nutrients was higher in the slash-and-burn than the green cane harvest scenario (Student's t-test, pMg>K>P. The SD rate was highest in areas with greater slope. Lower uncertainties were associated to the areas with higher SD and steeper slopes. Spatial uncertainties were highest for areas of transition between concave and convex landforms. Univ Estadual Paulista, Fac Ciencias Agr & Vet, Programa Posgrad Agron Ciencias Solo, Sao Paulo, Brazil Univ Fed Maranhao, Ctr Ciencias Agr & Ambientais, Chapadinha, Maranhao, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Programa Posgrad Prod Vegetal, Sao Paulo, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Solos & Adubos, Sao Paulo, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Ciencias Exatas, Sao Paulo, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Programa Posgrad Agron Ciencias Solo, Sao Paulo, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Programa Posgrad Prod Vegetal, Sao Paulo, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Solos & Adubos, Sao Paulo, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Ciencias Exatas, Sao Paulo, Brazil