中文摘要：

在安西极旱荒漠自然保护区的典型植物群落中选取6个平行样方，连续3年调查植物数量、盖度和物种数量的季节变化和年际变化以及气候对植物群落季节变化和年际变化的影响．结果显示：植物群落物种数量和植株数量的季节变化主要是由一年生草本植物的季节变化引起的，而多年生濯木盖度的季节变化是植物群落盖度变化的主要原因．植物群落物种数量、植株数量和盖度的年际变化主要源于一年生草本植物物种数量、植株数量和盖度的变化．植物群落物种数量、植株数量和盖度的季节变化与降雨量和气温的变化正相关，而年际变化与降雨量和气温的变化关系不大．因此，降雨和气温仅影响荒漠植物群落结构的季节变化，而对年际变化影响不大．在气候条件变化较小的范围内，荒漠植物群落结构保持相对稳定的结构．

英文摘要：

Six parallel plots of plant community in the Anxi Extra-arid Desert National Nature Reserve were selected for three consecutive years to investigate the seasonal and inter-annual variations of their vegetation quantity, coverage, the number of species and the impact of climate change. The results showed that the seasonal variations of the number of species and the number of plants in plant communities were mainly caused by the seasonal variation of annual herbaceous species, and the changes in community coverage were caused by the seasonal variations of the perennial shrub cover. Interannual changes in the plant communities, in a number of species, a number of plants and their coverage were mainly caused by the interannual variations of annual herbs. The seasonal variations of the number of species, the number of plants and the coverage in plant communities were positively related to the changes in both local rainfall and temperature, and there was no relation between them in interannual variability. It could be determined that rainfall and temperature had a greater impact onthe seasonal variations of desert plant community structures, but had little impact on the interannual variations. Within a smaller range of changes in climatic conditions, the desert community can maintain a relatively stable structure.