ABSTRACT
Soil mesofauna consists of organisms that measure from 0.100 μm to 2 mm, being important to evaluate methods employed for its characterization. The objectives of this study were to define how long the soil material must remain in the Berlese-Tüllgren extraction device to capture organisms of the mesofauna and determine the minimum extraction time for correct use of the Shannon, Simpson, Pielou, and Margalef indices used to evaluate the diversity, dominance, and richness of the mesofauna communities. The study was conducted at the Department of Soil Science at the Institute of Agronomy of the Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil, in highly anthropic land. Experimental plots were set up with the following treatments: jack bean (Canavalia ensiformis), velvet bean (Mucuna aterrima), Ceará bravo bean (Canavalia brasiliensis), pigeon pea (Cajanus cajan), and spontaneous vegetation in a Latin square design. Samples were collected from each of the experimental units, made up of plant litter and soil material in the first 5 cm of topsoil the day before planting legumes (October), and, subsequently, at the time of cutting plant shoots (March). The samples were subjected to a battery of the Berlese-Tüllgren type funnels for a period of 15 days, performing a daily count of organisms. From the count and group-level identification (Order/Family) of the captured organisms, the Margalef, Simpson, Shannon, and Pielou indices were determined and verified by Kendall rank correlation between the values obtained from one day to the next until the 8th day of extraction, using the Shannon index as a reference. From the study, it may be concluded that it is possible to reduce the time the material samples remain in the Berlese-Tüllgren funnels, but adoption of a time less than six days is not recommended to determine the composition of the soil mesofauna or to obtain more consistent and reliable data for evaluating diversity indices when using this procedure.
Berlese-Tüllgren method; Shannon index; Simpson index; Pielou index; soil ecology
