Soil mesofauna in consolidated land use systems

how management affects soil and litter invertebrates

Abstract

Soil mesofauna consists of small invertebrates that live in the soil or litter and are sensitive to climatic conditions, management systems, plant cover and physical or chemical soil attributes. These organisms are active in the cycling of nutrients, since they fragment the organic matter hereby accelerating microbial decomposition. The aim of this study was to evaluate the invertebrate community in no-tillage, conventional tillage, minimum tillage and secondary forest in regeneration to determine the relationship of mesofauna to litter, soil attributes, management and seasonality. Therefore, ten soil samples in each system and eight litter samples in no-tillage and the forest were taken over four seasons. These samples remained in Berlese extractors for seven days for quantification and identification of mesofauna. For each fauna sample, soil samples were collected for chemical analysis. Next, diversity indices and richness were calculated and multivariate analyses were used to establish relationships between the mesofauna, soil attributes and management. In the soil, mites were more abundant in the agricultural systems than in the forest, but the springtails, sensitive to low moisture and high temperature, were more abundant in the forest. Diversity and richness were higher in soil from the forest than under other systems. In no-tillage, there was a lower density of soil mesofauna, however, under this system, many invertebrates live in litter, since litter is the main food resource for them. In forest litter, we found lower invertebrate density and higher diversity than in no-tillage. Carbon, basic cations, pH, Al and V% were the attributes that best explained fauna variability in the systems.