Deep furrow and additional liming for coffee cultivation under first year in a naturally dense inceptisol

Abstract

Naturally dense soils have been commonly managed for coffee plantations in Vertentes Fields physiographic zone of Minas Gerais state, Brazil. Such dense soils in association with the irregular rainfall in recent years have increased risks for crop productivity. Therefore, management practices aiming at improving subsoil root exploration have been recommended for enhancing absorption of water and nutrient uptake, thus mitigating the edaphic drought process and ensuring the development, productivity, and longevity of the coffee crop. A field experiment was carried out in an area of dense Inceptisols through the planting of the coffee crop to investigate the effect of deep furrowing with additional liming on soil quality indexes and as a function of normalized pore distribution by volume [S*(h)]. The experimental design was in randomized blocks with 5 treatments: 40 (conventional soil preparation with furrows at 0.40 m of depth); 60 (soil preparation with furrow to 0.60 m of depth with conventional (60S) and complementary liming application (60C)); 80 (soil preparation with furrow to 0.80 m of depth with conventional (80S) and complementary liming application (80C)). These treatments were compared to an area under native Cerrado vegetation. Undisturbed soil samples were collected at different depths in each treatment. On these samples, water content was measured at different matrix potentials, and physical quality indicators along with the S*(h) were calculated. The results indicated that soil management practices, compared to the native condition, promoted a better distribution of water and air (PAWC, RFC, PMAC and S index) as well S*(h) up to 0.40 m. Below this depth, none of the management practices were able to promote significant improvements (p < 0.05) of these variables in relation to the soil native condition. The 80C treatment had the best air and water availability, with increased of pore size class having functions of drainage and aeration. Moreover, this treatment stood out in comparison to the conventional management (40) for all measured variables, maintaining the adequate conditions of the native area in depth. For the managed areas, the depth of 0.60 m gave the best improved growth and vegetative vigor of the coffee plants.