ESJ58 シンポジウム S03-4
Terutaka Mori (Aqua Restoration Research Center)
Variation in diversity-disturbance patterns has been observed for various taxa and has been explained by assumption that all can trade-off in their relative ability to compete and persist in patches and to colonize new patches. However, empirical studies have reported that species did not exhibit clear trade-off in traits assumed in those explanation. In this presentation, I will explain that variation in diversity-disturbance relationships between feeding guilds of stream invertebrates could be provided by both strength of density-dependent competition at the community-level and relative differences in the competition between dominant core taxa and rare satellite taxa: dominant core taxa, which were distributed in most study streams, did not show trade-off in traits, but rare satellite taxa, which were observed in only streams with low or high precipitation (i.e. low or high disturbance), did show trade-off in traits. When dominant core taxa have high community density, they may regulate the strength of density dependent competition in the study, leading to displacement of only rare satellite taxa.