Easy-to-obtain biological soil quality indicators for monitoring agroecological corn cultivation

Abstract

The soil is a natural resource of biotic and abiotic combinations affected by management and may significantly change their functionality. This study evaluates the impact of agricultural practices adopted under ecologically based management on corn cultivation compared with an adjacent native forest area. The study was developed in the experimental areas and laboratories of the Cascata Experimental Station - Embrapa Clima Temperado, Pelotas/ RS. The diversity of edaphic fauna was obtained by the PROVID method, which resulted in similarity in both environments. It was observed that the Shannon diversity index and Pielou equitability index were significantly higher in corn cultivation. Compared to Renyi's diversity profile, the edaphic fauna in corn presented a higher index of species than in the native forest (α<2), attributed to a greater source of food for some communities. The bait-lamina methodology was used for the feeding activity of the soil biota, evidencing an average activity in corn approximately 60% higher compared to the forest (48.14%). These indexes must be associated with the average content of OM present in the soil, being 6.04% in the forest and 2.39% in the corn, because when analyzed by the T-test, they present significant levels for the feeding activity. It is concluded that the assessment of the impact of agricultural practices adopted under ecologically based management in corn cultivation resulted in no significant difference when compared with the adjacent native forest area since levels of similarity between the environments were identified concerning biological parameters of the soil.