内蒙古草地植被δ13C空间格局及其对气候因子的响应

摘要 为了探明内蒙古草地植物叶片δ○13C的空间格局及其对气候因子的响应，于植物生长最旺盛的8月，在内蒙古共采集来自47个样地的126个C3植物样品，利用GPS记录每个样地的地理参数，并从全国陆地生态信息气象栅格数据库中提取每个样地的气象信息，在实验室利用同位素质谱仪测定叶片13C/12C.研究发现，C3植物叶片δ○13C随海拔升高而增大，随经纬度的增加而减小；降水和大气压强与叶片δ○13C显著负相关，它们共同决定了叶片δ○13C的空间格局，其中水分是主导因素；温度对叶片δ○13C没有显著影响.
Abstract：In order to explore the pattern and climatic control of foliar δ13C， 126 samples of C3-plant species were collected from 47 areas in the Inner Mongolia during its August prosperous season. The geographic parameters of each site were recorded by GPS， and climatic information of each site was extracted from Meteorological Database of the Chinese Ecological Research Network. Foliar 13C/12C ratios were determined by an isotope mass spectrometer. The results show that the increasing trend of C3-plant foliar δ13C excursion changes positively with the increase of altitude， but negatively with the increase of longitude and latitude degrees. Climatic factors controlling the C3-plant foliar δ13C variations are mainly involved in the amount of seasonal rainfall and atmospheric pressure， as well in negative relationships， which control spatial distribution of the C3-plant foliar δ13C. In addition， variations of foliar δ13C show nothing in trend of the temperature changes here.