植物功能群及其多样性对内蒙古草原氮周转的影响

The relationship between biodiversity and ecosystem function is the hot issue of the ecological studies. Nitrogen mineralization is one of the most important aspects of ecosystem function which is the key ecological process that influences and controls the ecosystem productivity and stability. Evaluation of the relationship between plant functional group diversities and nitrogen turnover is crucial to make the appropriate grassland management rules and maintain the sustainable ecosystem development since Inner Mongolia Grassland is an important animal husbandry base in China. However, the effect of plant functional group diversity on nitrogen mineralization, especially gross mineralization is still unclear. This project will be conducted in the biodiversity and ecosystem function experiment platform which was established in 2005, managed by the Inner Mongolia Grassland Ecosystem Research Station. The effects of the plant functional groups and functional group diversity on net and gross mineralization, microbial carbon, nitrogen and microbial communities will be measured in the whole year scale. This project is the first time developing the plant functional groups by removal in natural grassland, which is more close to nature than cultivation. The innovations of this project are: (1) determination of the impacts of plant functional group diversities on gross mineralization, which can indicate the N turnover of soil organic nitrogen more accurately than net mineralizaiotn; (2) assessing the relations of soil microbial communities and nitrogen mineralization, which can help to understand the mechanism of nitrogen mineralization; (3) measuring the whole year N mineralization, which is important to evaluate the real available nitrogen produced by the northern grasslands.

生物多样性与生态系统功能的关系是当今生态学研究的热点问题。氮矿化是生态系统功能的重要方面，是影响和控制生态系统生产力与稳定性的关键生态过程。内蒙古草原是我国重要的畜牧业基地，研究植物功能群多样性与氮周转的关系对制定合理的草原管理方式,维持生态系统的可持续发展意义重大。目前，植物功能群及其多样性对氮矿化尤其是总氮矿化的影响还不清楚，亟待研究。本项目在中科院内蒙古草原站2005 年建立的生物多样性与生态系统功能实验平台进行，在全年尺度上研究不同植物功能群和功能群多样性对土壤净氮矿化和总氮矿化的影响，同时监测微生物碳、微生物氮、微生物群落变化。本项目的特色是首次采用人工剔除功能群的方式进行实验处理，比人工群落更接近自然，其创新点在于：（1）测定植物功能群多样性对总氮矿化的影响，能够更准确的反映有机氮的矿化过程；（2）研究土壤微生物群落与氮矿化的关系，能够从机理上了解生物多样性对氮矿化的影响

生物多样性与生态系统功能的关系是当今生态学研究的热点问题。氮矿化是生态系统功能的重要方面，是影响和控制生态系统生产力与稳定性的关键生态过程。内蒙古草原是我国重要的畜牧业基地，研究植物功能群多样性与氮周转的关系对制定合理的草原管理方式,维持生态系统的可持续发展意义重大。目前，植物功能群及其多样性对氮矿化尤其是总氮矿化的影响还不清楚，亟待研究。本项目在中科院内蒙古草原站2005 年建立的生物多样性与生态系统功能实验平台进行，在全年尺度上研究不同植物功能群和功能群多样性对土壤净氮矿化和总氮矿化的影响，同时监测微生物碳、微生物氮、微生物群落变化。本项目的特色是首次采用人工剔除功能群的方式进行实验处理，比人工群落更接近自然，其创新点在于：（1）测定植物功能群多样性对总氮矿化的影响，能够更准确的反映有机氮的矿化过程；（2）研究土壤微生物群落与氮矿化的关系，能够从机理上了解生物多样性对氮矿化的影响。研究发现，植物功能群多样性对总氮矿化、微生物量具有显著的影响，功能群多的生态系统具有较高的总矿化和微生物量，功能群多样性对净矿化没有显著的影响。然而，不同功能群对微生物和氮矿化的影响也是不同的，根茎型禾草具有显著的影响，而一、二年生杂类草无显著影响。