Aims To study the relationship between changes in soil properties and plant community characters produced by grazing in a meadow steppe grassland and the composition and diversity of spore-producing arbuscular mycorrhizal fungi (AMF). Methods A field survey was carried out in a meadow steppe area with a gradient of grazing pressures (a site with four grazing intensities and a reserve closed to grazing). The AMF community composition (characterized by spore abundance) and diversity, the vegetation characters and soil properties were measured, and root colonization by AMF was assessed. Results AMF diversity (richness and evenness) was higher under light to moderate grazing pressure and declined under intense grazing pressures. Results of multiple regressions indicated that soil electrical conductivity was highly associated with AMF diversity. The variation in AMF diversity was partially associated to the density of tillers of the dominant grass (Leymus chinensis), the above and below-ground biomass and the richness of the plant community. Conclusions We propose that the relationship between plants and AMF is altered by environmental stress (salinity) which is in turn influenced by animal grazing. Direct and indirect interactions between vegetation, soil properties, and AMF community need to be elucidated to improve our ability to manage these communities.

No abstract

Native grassland in China is mostly meadow, typical or desert steppe and comprises 400 million hectares, ~40% of the land area. We review past research on the meadow steppe of north-east China. Our foci are plant adaptation to climate, edaphic-related and defoliation stresses, vegetation production, grassland management, herbivore foraging behaviour, safe stocking rates, plant-animal interactions, ecosystem functioning, conservation of biodiversity and the influence of climate change on grassland function. Recent studies have provided some insights into ecological processes and functioning of meadow steppe, and have enabled better identification of research opportunities. Key areas identified for future research include plant adaptation, grassland function and value, monitoring of range health, ecological consequences of climate change on biodiversity and ecosystem function.

No abstract

No abstract