Effect of Canavalia ensiformis on organic matter and carbon contribution of a Fluvisol soil

Abstract

The balance of soil organic carbon and soil organic matter are key factors in the sustainability of agroecosystems, since carbon reserves and soil fertility depend on the management practices applied. Conversion or changes in ecosystems may lead to losses or gains of carbon, conditioned by soil use. Among the alternatives studied, the use of green manures such as Canavalia ensiformis has shown positive effects on soil properties. The objective of this research was to evaluate the effect of Canavalia ensiformis as green manure/cover crop on the organic matter and organic carbon of a Fluvisol soil located in Santiago de Cuba municipality. A completely randomized design was applied in a 2 x 3 factorial arrangement (cover × evaluation time), with a fallow control (Cn) and a permanent cover of Canavalia (CCp), evaluated at 0, 200, and 280 days. At the start of the study, the soil showed a heterogeneous fertility status, with low organic matter and nitrogen content and high available phosphorus and potassium content. Results revealed increases in soil organic carbon and organic matter compared to the initial condition, with the highest values in the treatments with permanent legume coverage, as their life cycle remained uninterrupted. Canavalia ensiformis represents an effective strategy to increase organic matter and organic carbon in Fluvisols, contributing to fertility conservation and edaphic ecosystem services in tropical environments.