Acúmulo de nutrientes e estoque de carbono pelo abacaxizeiro Pérola submetido a diferentes lâminas de irrigação

Abstract

The pineapple when irrigated presents high production of plant biomass, resulting in a greater production of dry matter for area. Considering the high nutrient demand of the pineapple, the fertigation in cultivation of this species makes the culture even more productive. The increase in organic matter in the soil in addition to benefit from the aspects physical-chemical-biological soil, collaborates with the stock of C and N in the soil. The objectives of this study were to evaluate the accumulation of nutrients and the stock of C and N in the soil and the biomass of the pineapple 'Pearl' drip irrigation under different slides of irrigation. The experiment was carried out in experimental area of the Unimontes-MG, in a Typic Fluvico. The experiment was carried out in a randomized block, with five treatments: 30% of the evaporation of the Class A tank (691.2 mm year'); 50% of the ECA (1,152.0 mm year'); 70% of the ECA (1,612.8 mm year'); 100% of the ECA (2,304.0 mm year'); 150% of the ECA (3,456.0 mm year), four repetitions. Being that for the determination of the accumulation of nutrients, carbon and nitrogen in the biomass were collected from four plants per plot. For determination of COT and NT of the soil were collected from six simple samples that comprised a composite sample at a depth of 0-0.2 m. The sequence of accumulation of nutrients in the whole plant was: K>N>Ca>S>P>Mg. And the micronutrients presented the following order: Fe>Mn>Zn>Cu>B. The fruits exported the area of cultivation mainly K (17.52 kg ha-1); N (16.66 kg ha¹) and Ca (11.05 kg ha). The smaller C stocks (36.32 Mg ha¹) and N (1.22 Mg ha¹) of the soil were observed when applied to the blades of 98% and 96% of the ECA, respectively. This shows that slides above 70% of the ACE may promote in addition of the leaching of nutrients to the acceleration of the decomposition of soil organic matter.