Soil oribatid mite in four typical vegetation communities of Misiones forest in the Iguazú area, Argentina

Abstract

The aim of this work was to compare the species composition of the oribatid mite community in soils of areas with different vegetation communities in the Iguazú National Park and bordering areas, in Misiones province, northeastern Argentina. This area belongs to the Upper Paraná Atlantic Forest. Soil samples were taken in four sites: under palm trees, dominated by heart of palm (Euterpe edulis) trees and rosewood (Aspidosperma polineuron); under forest gaps dominated by bamboos (Chusquea ramosissima), and in two different secondary forests outside the park. Around 80 species of oribatids were found. A similarity index (Jaccard) among zones was calculated. Specific composition was compared with other areas in the region (Paraguay and south of Brazil) in order to make biogeographic inferences. The richest sites were secondary forests biotopes. Similarity was highest (0,5) among richest sites, whereas among the remainder sites was lower than 0,35. At species level, the studied community has many species in common with those of Sao Paulo State in Brazil (bibliographical data), and at genera level similitude is higher. The distribution of oribatid mites species and genera seems determined by biogeographic region´s boundaries (Atlantic Forest) more than by subregion´s ones (Upper Paraná Atlantic Forest). The results could be useful in recognizing vegetation communities they are associated with and there be applied in the development of sustainable management strategies for the protected areas

O objetivo deste trabalho foi avaliar as comunidades de oribatídeos em quatro sítios da Mata Atlântica do Alto Paraná, na área do Parque Nacional Iguazú, Argentina, e em áreas adjacentes: floresta de bambu, floresta de palmito e duas florestas mistas. Foi feita uma comparação de cada par de sítios, com base na presença/ausência de oribatídeos, por meio do índice de Jaccard. Esta é a primeira amostragem sistemática dos oribatídeos dessa região. Cinquenta e seis gêneros e 96 espécies de oribatídeos foram encontrados, dos quais 25 e 49, respectivamente, são citados pela primeira vez para a Argentina. A maior similiraridade foi encontrada entre as duas florestas mistas. Quase 68% e 34% dos gêneros já foram coletados em biótopos similares no Brasil e no Paraguai, respectivamente.