The Relationship Between Phenological Pattern And Ecosystem Function In Natural Steppe Community

Human activities are triggering some of the most rapid species extinctions in global scale. These changes in biodiversity have a strong potential to alter ecosystem properties and the goods and services they provide to humanity. Whether there is a point at which changes in properties might adversely influence human welfare is a major issue of ecologist. In spite of many efforts, however, there remain important aspects that are still not well understood.There has been substantial debate within the ecological community on the interpretation of some recent research and whether the findings from these studies are as important as other factors that are well known to correlate with ecosystem functioning in nature. Based on the reviews of researches, we generalized the recent advances and controversies on biodiversity and ecosystem function. A three years experiment was conducted within Inner Mongolia steppe. Natural Steppe community was degraded because of have grazing. We investigated the relationships between biodiversity, primary production and ecosystem stability during the period of restoration. We focused on the influences of temporal niche partition, sampling strategy and the time of restoration on the relationship between biodiversity and ecosystem function. Major conclusions are as blow.1.High resource use efficiency caused by temporal niche complementarity is an important underling mechanism of the positive relationship between species diversity and primary production in natural grassland community.2. Increasing both species richness and species evenness would lead to a high degree of temporal niche partition in Inner Mongolia steppe.3. For the relationship of species diversity and primary production, single sampling strategy within growing season would lead to underestimated of complementarity effect because of neglect of temporal niche complementarity in plant communities. Multi-sampling strategy would be more reasonable in communities with phenological pattern.4. The effect of diversity on primary production differs in different restoration stage. The unimodal pattern indicates there has turnover on the underling mechanism.5. Measured by variation of community biomass, stability was not related to species diversity. The correlations between major component species were positive or none. Abiotic factors may have more effects than biotic factors.6. The underling mechanism of species diversity on primary production and ecosystem stability was different. There is no correlation between overyielding and community biomass stability.7. Contrast to community biomass stability, overyielding effect is more stable in higher diversity level between years.