Atributos físicos de um neossolo sob sistema de integração lavoura-pecuária no semiárido brasileiro.

Abstract

The physical degradation of the soil was pointed as one of the biggest inputs for the development of agriculture in the country, mainly due to the inadequate practices of soil and pasture management and conservation. Impaired crop development requires the adoption of conservationist production systems that reduce the impact of physical soil degradation. Integrated production systems such as Livestock Farming (iLP) increase as a sustainable sustainable alternative through the number of benefits it provides to the soil. The objective of this study was to evaluate the physical attributes of a Regolithic Neosol under different management systems in the Brazilian semiarid. The experiment was conducted at Embrapa's Technological Reference Unit, located in the experimental area of the Paraiban Company for Research, Rural Extension and Land Regularization (EMPAER), in Lagoa Seca, in the wild of Paraíba. The experimental design was randomized with 5 treatments and five replications (5 x 5), in two depths (0.00 - 0.10 and 0.10 - 0.20 m). The controls applicable to crop-livestock integration systems were: 1) Urochloa + Corn Grass (CU + M); 2) Brachiaria decumbens + Corn (BRA + M); 3) Forest (FLO); 4) Agriculture Area with bean cultivation (AGRI); 5) Degraded area (DG). The samples were sent to the Soil Physical Analysis Laboratory of the Department of Soils and Rural Engineering of the Federal University of Paraíba for analysis. The variables analyzed were: Soil density (ρ - kg dm-3), porosity (Total (α), macroporosity (MA) and microporosity (μ) (in m3 m-3), aeration porosity (β - m3 m- 3), saturated hydraulic conductivity (Kθ cm h-1), field capacity (θCC), permanent wilting point (θPMP) and available water range (θAD), Sand, Silt, Clay, Water-dispersed Clay (ADA) ) and the degree of flocculation (GF) in g kg-1. Variance analysis was performed and the means were compared using the Tukey test at 5% probability, with the aid of the software. (80%) in most of the evaluated treatments, classifying the soil as open sand and sand.The total porosity, macroporosity, soil density, and saturated hydraulic conductivity were higher in the forest treatment at depth 0.0-0.10. treatment (CU + M) presented higher values for Field Capacity at depths 0.0-0.10 and 0.10 m-0.20 m. The microporosity was higher in the treatment (BRA + M) at the depths 0.0 m-0.10 m and 0.10 m-0.20 m. The best available water volume was in the 0.0 m-0.10 m layer was observed in the treatment (CU + M), while for the 0.10 m-0.20 depth, the same variable presented the highest values for the treatment. treatment (DG). Therefore, the crop-livestock integration treatment that presented the best physical attributes was Urochloa Grass + Corn.