Atributos físicos, químicos e estoque de carbono em argissolo sob diferentes manejos na zona da mata de Pernambuco

Abstract

The large national sugar and ethanol production generates several residues in its production process. Among these residues is vinasse, which if not well managed can cause serious environmental impacts. The objective of this work was to evaluate changes in the chemical, physical and biological attributes of the soil cultivated with sugarcane. Four types of treatments with vinasse, mechanized harvesting, harvesting with raw cane and supplemental irrigation were used in four different experimental units at three depths (0 - 20 cm, 20 - 40 cm and 40 - 60 cm), and with three replicates. The soil used was classified as Argissolo Vermelho Amarelo Distrófico textura média, grown in the productive field of the Petribú Plant in the municipality of Paudalho - PE, with the variety of sugarcane RB867515. The results of the physical, chemical and carbon stock analysis were submitted to ANOVA and compared by the Tukey test using the statistical program ASSISTAT 7.7 beta, in a Completely Randomized design, in a factorial scheme with three replicates, evaluating the occurrence of interactions between treatments x depths. For the analysis of vinasse, roots and respirometry, were made descriptions of the data found, comparing the different treatments. The results show that the treatments with vinasse application, present the best results for the availability of nutrients in the soil. The experimental unit without vinasse application had acid pH and high levels of saturation by aluminum, causing a decrease in the availability of nutrients to the soil. Regarding the carbon stock in the soil, the treatments did not produce significant differences. For the physical attributes, the soils handled with vinasse showed to be more compacted, emphasizing the treatments with mechanized harvesting. For the biological attributes, soils handled with vinasse presented the best values for basal respiration of the soil, but did not interfere in the soil dry matter content. Soils treated with vinasse provided an increase in productivity, possibly due to the increase in nutrient availability.