Abordagem eco fisiológica para avaliar a evolução do carbono no solo

Abstract

By 2050, agricultural productivity will need to be nearly 50% higher than levels observed in 2012. This highlights the need for a production and development model that reconciles agricultural growth with the conservation and sustainability of agroecosystems. The use of management practices capable of increasing stable soil organic matter content is essential to this process. Practices such as the use of high-quality biomass and fertilization with polyvalent cations facilitate this. Therefore, this study aimed to evaluate the interaction effect between high-quality biomass and the polyvalent cations Ca and Si on biological quotients, and how this effect influences the accumulation of the stable fraction of soil organic matter. To achieve this objective, the variables evaluated were the metabolic quotient (qCO2), microbial quotient (CBM:C), calcium, and silicon. A randomized block design was used, comprising eight treatments and four replicates. The treatments consisted of combinations of legumes with calcium, silicon, and urea. The combination of silicon and legume biomass demonstrated the highest carbon use efficiency and the greatest incorporation of organic carbon into microbial biomass. However, the results indicated that combining legume biomass with both polyvalent cations enhanced microbial activity, which in turn promoted the accumulation and stabilization of organic carbon (C-org) within the soil organic matter.