Abstract 86
Pavlíček, T. and Nevo, E. 2008. Local species richness distribution at “Evolution Canyon” microsite, Mt. Carmel, Israel. Ecologia Mediterranea 34: 25-34.
We evaluated the interslope and intraslope distributions of species richness in 17 taxa representing cyanobacteria, lower plants (Agaricales, lichens, mosses), invertebrates (butterflies, grasshoppers, oribatid mites, springtails, carpet, darkling, dung, hister, jewel, and leaf beetles), vertebrates (reptiles), and two rather ecological groups (soil fungi and woody plants) at the microsite “Evolution Canyon”, lower Nahal Oren, Mt. Carmel, Israel.

At least seven, out of all the studied ones, showed significant differences in species richness between the “African savanna-like” south-facing slope (AS) and the “European garrigue-like” north-facing slope (ES) separated by a distance of a 100 m at the valley bottom.

Four clusters representing the studied taxa could be distinguished according to inter- and intraslope species richness distributions. The “heat-dependent” taxa (reptiles, butterflies, darkling beetles) behaviourally adjust for heat gain and show a propensity for the more illuminated,drier, warmer, “AS”. Grasshoppers, carpet, and leaf beetles were more speciose at “AS” as well, but this might relate to the annual plants cover. The “humidity-dependent” taxa (soil fungi, springtails, mosses, Agaricales, woody plants, oribatid mites) share their propensity for higher environmental humidity, higher amount of water on the cooler “ES” covered by the dense Mediterranean garrigue.

Except for the oribatid mites, their species richness followed a downslope trend of increasing humidity and water runoff on both slopes. Our results indicate that environmental factors related to the specific slope microclimate - mainly water and energy – should be considered as factors influencing the local distribution of species richness.