Manejo do solo e produtividade do arroz de terras altas no sul do Amazonas

Abstract

The study reveals how soil management can boost agricultural productivity, promoting sustainability and innovations in rice cultivation in the southern Amazon region. The objective of this work is to quantify the dynamics of soil physical attributes and the impacts of scarification, harrowing, direct seeding and liming management on the productivity of crops in rotation and succession (Brachiaria and Rice), aiming to establish the effective soil preparation practice that best adapts to the soil and climate conditions of the study. The research was carried out in the area of the Mangabeira Experimental Farm (Figure 1), of the Institute of Education, Agriculture and Environment, of the Federal University of Amazonas, located in the municipality of Humaitá, AM under the geographic coordinates 7º31'49.51" S and 63º3'14.62" W with an altitude of 60 m. The variables analyzed were: Density (Ds), Water content in saturated soil (θ Sat), Water content at 10cca (θ 10cca), Total Porosity (PT), Microporosity (MICRO), Macroporosity (MACRO) and Soil resistance to penetration (RP) under two factors: Soil Management (MS): Conventional Management (MC), No-Tillage (PD) and Management with scarifier (Esc) and liming at doses of 0, 2, 4 and 6 t. ha-1. The variables were analyzed at two moments, Moment 1 (M1) and Moment 2 (M2). All analyses were evaluated by Tukey's test at 5% probability in Sisvar software, version 5.3. MS Esc was the one that presented the best means for soil physical quality, in addition to having the best productivity. The limestone dose that had the best results among the doses studied was 6 t. ha-¹, both for grain and straw production. There was a significant increase in macroporosity with grass rotation. The half-life of Brachiaria cv. Marandu was 20 days.