ANÁLISE MULTIFRACTAL E JOINT MULTIFRACTAL DA FAUNA EDÁFICA SOB CULTIVO DE CANA-DE-AÇÚCAR.

Abstract

Climate change has led most countries to look for alternative energy sources to fossil fuels. This fact caused an increase in demand for ethanol, a biofuel obtained from processing and fermentation of various plants, mainly from sugarcane. The growing demand for ethanol caused an expansion of sugarcane production, which now occupies new areas, previously covered by native forest. These changes have impacts on the edaphic fauna, which is impoverished in terms of diversity and abundance. It also impacts ecosystem services, impairing soil fertility and stability. Little is known about the spatial variability of soil fauna under cultivation of sugarcane and its relation to the attributes which are closely related, such as soil carbon, especially about their behavior in multiscale. Thus, this study aimed to analyze the behavior of the spatial distribution of altitude, carbon and soil fauna in sugarcane cultivation and their relationships, using multifractal techniques. The soil fauna and the chemical and physical attributes were sampled by transect in a sugarcane cultivation area located in the municipality of Goiana (Pernambuco, Brazil). From these data the multifractal and joint multifractal analysis was performed, resulting in the generalized and singularity spectra and the contour plots of the joint distributions of the data. The variables showed differences in multifractal behavior, and the results showed a greater degree of multifractality for social insects and individual trap-1 day-1, whereas carbon, regardless of how it is analysis showed a more homogeneous structure, tending to monofractal behavior. These differences are attributed to the dynamics of sugarcane cultivation itself, which has low carbon content throughout the cultivation history and favors few groups, such as Formicidae, which has great variation in eating and behavioral habits. The joint multifractal analysis showed a greater relationship between the pattern of spatial distribution of diversity and altitude, which is explained by the very effect that altitude has on other attributes, influencing the pattern of carbon accumulation, and consequently of the soil fauna. Characterizing the behavior of the edaphic fauna in sugarcane and its relationship with carbon content or altitude is useful for the conservation of sugarcane agroecosystems, since it detects a low diversity because it indicates poor soil fertility, thus It makes soil fauna useful for conservationist crop management.