Effect ofhabitat degradation on soil meso- and microfaunal communities in the Zoige Alpine Meadow, Qinghai-Tibetan Plateau

Soil fauna plays an important role in nutrient cycling and energy flow, and is also an important driver of ecosystem succession. The Qinghai-Tibetan Plateau, with an area of 2.5 million square kilometers, and elevation of over 4,500 meters, has been called "the third polar area of the earth". The wetlands of the Qinghai-Tibetan Plateau are an important biodiversity area. The Zoige Wetland, located on the eastern Qinghai-Tibetan Plateau, is a typical example of an alpine meadow. Since the 1950s, the Zoige Wetland has degraded as a result of global change and human activity, and parts have become desert-like with little plant coverage. The effect of this degradation on the structure and diversity of the below-ground soil biota is unknown. To investigate the effects of degradation on the soil meso- and microfauna in Zoige Alpine Meadow, three degradation stages (marsh meadow, grassland meadow and sand meadow) were selected, and examined in July and October, 2008. A total of 9,450 individuals were captured from the soil meso- and microfauna, and classified into 4 phyla, 5 classes, 12 orders, 70 families and 104 taxa. The community was found to be dominated by nematodes, accounting for 85.79% of the individuals. Other common taxonomic groups were Arachnida (8.73%), Collembola (3.24%), Oligochaeta (1.32%), and insects (0.88%). In both July and October, abundance, richness and diversity in soil meso- and microfaunal communities were observed to be significantly less (P