| 要旨トップ | 目次 | | 日本生態学会第63回全国大会 (2016年3月、仙台) 講演要旨 ESJ63 Abstract |
一般講演(ポスター発表) P1-188 (Poster presentation)
The intermediate disturbance hypothesis (IDH) states that diversity of competing species is expected to be maximized at intermediate intensities of disturbance. We tested this hypothesis in frog communities in a tropical forest in Ranomafana, which harbors the richest amphibian communities in Madagascar. We compared the diversity and abundance of stream breeding frogs in three habitats along a gradient of habitat disturbance: primary forest, selectively logged forest and in adjacent agricultural areas. We hypothesized that species richness and abundance would be relatively low in agricultural areas and highest in selectively logged forest, following the predictions of the IDH. In each habitat, we established four 50 m permanent nocturnal line transects, each was walked 13-16 times over three breeding seasons. Frog abundance and average species number per stream did not differ between the agricultural areas and the selectively logged forest but were highest in the primary forest. Species diversity was highest in agricultural areas though. The pattern of species diversity is not in line with the predictions of the IDH. Edge effects and spatial variables could play important roles in structuring amphibian communities in this system as recently suggested in other tropical regions.