中文摘要：

通过对锡林郭勒盟锡林河流域羊草草原地区1981～1994年14年的温度观测和植被调查数据的逐年滑动平均处理,分析该地区气候和植被随时间的动态变化特征.结果表明,内蒙古羊草草原地区的气温在研究期内具有高低温变化不对称的特点,表现为全年最低温升高明显,最高温和平均温升高不明显.羊草草原的建群种羊草和大针茅对气温变化有不同的响应,最优建群种羊草的重要值和地上初级生产力随着最低温的升高有明显的下降趋势,次优建群种大针茅的重要值和地上初级生产力由于种间互补作用而略有升高.可以认为,如果这种趋势继续下去,大针茅有可能代替羊草,成为群落的最优建群种,使得群落的结构和功能发生改变.在研究与模拟羊草草原对温度变化的响应时,研究不同温度因子和年温度不同时段的变化特征,以及不同物种之间的竞争关系,有助于认识单个种群和整个生态系统对全球变化响应的机理.

英文摘要：

Based on the 1981- 1994 investigation data about the temperature and vegetation ot Leymus chinensis grassland in Inner Mongolia of China, this paper analyzed the dynamics of climate and vegetation change in this area. The results showed that the minimum temperature of this area increased faster than the maximum and average temperature. The importance value and above ground net primary productivity （ANPP） of L. chinensis, the first constructive species of the grassland, decreased because of global warming during the period of 1981 - 1994, while those of Stipa grand;s, the second constructive species, increased in view of competition. If these trends went ahead, there existed the possibility that S. grandis might replace L .chinensis, and gradually become the dominant constructive species, which would in turn change the structure and function of the grassland. The competition between dominant species should be paid attention in the studies on the responses of L. chinensis grassland to temperature change, which would be helpful to understand the response mechanism of individual species and ecosystem to global climate change.