Soil, water and nutrient losses by interrill erosion from green cane cultivation. Silva et al., 2012 Silva GRV, Souza ZM, Martins Filho MV, Barbosa RS, Souza GS. Perdas de solo e nutrientes por erosão num Argissolo com resíduos vegetais de cana-de-açúcar. This practice, from the point of view of soil and water conservation, has been a matter of concern and the focus of a number of studies, for tending to increased nutrient losses due to erosion ( Martins Filho et al., 2009 Martins Filho MV, Liccioti TT, Pereira GT, Marques Júnior J, Sanchez RB. Ĭontrolled burning of cane fields prior to manual harvesting is still a common practice in several sugarcane regions of Brazil, with the objective of reducing the amount of cane straw, thus facilitating the cutting and mechanical loading operations. Efeito de sistemas de colheita de cana-de-açúcar nos atributos físicos de um Latossolo Vermelho. In view of the expansion of the sugar and ethanol industry, changes in the sugarcane management system may have a significant impact on the Brazilian production, since the form of sugarcane harvesting can influence crop yield and longevity, the physical, chemical and biological properties, and the environment ( Souza et al., 2006 Souza ZM, Beutler AN, Prado RM, Bento MJC. Acompanhamento da safra brasileira: cana–de–açúcar. Currently, an area of 8,838.5 thousand hectares is growing sugarcane, distributed in all producing states, of which São Paulo has the largest output, accounting for 51.6 % of the total production, grown on 4,558.4 thousand hectares ( Conab, 2017 Companhia Nacional de Abastecimento - Conab. The sugarcane production for the 2017/18 growing season is estimated at 647.6 million tons. Green cane burnt cane geostatistics indicator krigingīrazil is the world's largest sugarcane ( Saccharum spp.) producer and within the country, it is the second most cultivated crop, only after soybean. In the BC, areas with steeper slopes were more likely to exceed the threshold with lower uncertainties. The production cycle allowed the delimitation of priority areas for the adoption of conservation practices in each management. From the 4 th harvest under GC, the probability of the soil loss exceeding the threshold was above 80 % in zero percent of the area, whereas, for BC, the probability exceeded 80 % in 40 % of the area. With the exception of the 5 th harvest and the entire cultivation cycle under GC, all soil loss estimates were spatially dependent. Soil losses from the BC were highest, during all five harvests. Areas with soil loss risks above the threshold were identified based on probability maps, generated from the individual and combined dichotomous variables. The temporal uncertainty was determined by integrating the estimated annual probabilities, representing the harvests. The probability that the soil loss would exceed the tolerable limit of 6.67 t ha -1 yr -1 was estimated for each management scenario and after the five harvests. A regular 626-point sampling grid was established in the area, with equidistant intervals of 50 m and a final plant density of about 3.3 samples per ha. The study was carried out on a 200-ha area, in Tabapuã, São Paulo State, Brazil. The purpose of this study was to evaluate the spatial and temporal uncertainty of soil loss under two scenarios of sugarcane harvest management: green cane (GC) and burnt cane (BC). Thus, the best way to estimate the spatial pattern of soil erosion must be identified, in which the process uncertainties are also taken into consideration. The identification of erosion-susceptible areas is fundamental for the adoption of soil conservation practices.
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