Seasonal and spatial variation in nematode communities in a negev desert ecosystem.

Seasonal and spatial variation in soil nematode communities was investigated in a field study conducted on a loessial plain in the northern Negev Desert, Israel. Soil samples from 0- to 50-cm depths were collected seasonally during 2001 under the canopy of Atriplex halimus and Hammada scoparia, and between shrubs (control). Total population abundance ranged from 8 to 887 individuals per 100 g soil, represented by 32 genera from 16 families. Significant temporal and vegetation effects were elucidated using most ecological indices applicable to express nematode community composition. Of those indices computed, only the Shannon index, the modified maturity index, and genus dominance distinguished differences in vertical distribution.