To conserve pasture dung beetles that feed and decompose animal dung and utilize their beneficial ecosystem functions for sustainable livestock production, we surveyed scarabaeoid dung beetles and predicted the landscape conditions of pastures favorable for rich dung beetle diversity by analyzing surrounding landscape of the pastures. We collected dung beetles monthly during the grazing period (May - October) from 1999 to 2001 on 18 pastures in the north-eastern part of Tochigi prefecture using dung-baited traps. We chose 10 major landscape elements (broad-leaved deciduous forest, coniferous forest, artificial forest, shrub land, grassland, paddy field, crop field, pasture, urban area, and water area) that possibly cause dung beetle habitation from the GIS data (5th ed., Ministry of Environment) and calculated the fractal dimension of each element in 4 km square area around the survey points by the box-counting method. In total, 49,577 individuals form 25 species belonging to Geotrupinae, Scarabaeinae and Aphodiinae were caught. Except for the forest specialists of
Phelotrupes laevistriatus, Copris acutidens and
Onthophagus nitidus, the species were those inhabiting grasslands, or both grasslands and forests. Species richness varied from 7 to 17 across the pastures. By stepwise multiple regression analysis setting species richness as dependent variable and fractal dimensions of the landscape elements as independent variables, we obtained a prediction model explained by fractal dimensions of broad-leaved deciduous forest and pasture having a positive coefficient and that of artificial forest having negative coefficient. Based on the model, we drew a contour map that predicts species richness of dung beetles in this area.
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