中文摘要：

在5个（A～E）直径不同的开顶式增温小室（OTCs）环境条件下,通过连续5年（2002～2006）的野外试验,分析了植物生长季矮嵩草草甸植物群落地上部分生物量、平均高度、盖度对模拟增温的响应.结果表明：（1）开顶式增温小室能够有效改变微气候环境,室内气温比室外增加0.24～3.41℃,其增温幅度与温室面积大小呈显著负相关（r=-0.993 1＊）.（2）随着试验时间的持续,各温室植物群落地上部分生物量均逐渐升高,第1年以温室B略高（202.01 g/m2）,而第5年以温室A最高（414.56 g/m2）且显著高于其它处理和对照（P〈0.05）.（3）植物群落平均高度在同一温室呈逐年增加的趋势,第5年显著高于其它年份（P〈0.05）;而不同温室间的植物群落平均高度随着室内温度的增高而逐渐显著增加.（4）植物群落总盖度呈逐年上升的趋势,至第5年已接近或达到100%;各温室间分盖度之和无显著差异（P〉0.05）,而其年际间变化差异极显著（P〈0.001）,2004～2006年分盖度之和均极显著高于2002和2003年,而2003年又显著高于2002年.可见,随着温室气温的逐渐增加,矮嵩草草甸植物群落地上部分生物量、平均高度、盖度均表现为逐渐上升的趋势.

英文摘要：

We analyzed biomass,average height,coverage of the plant community of Kobresia humilis meadow during plant growing season to simulate environmental temperature change during 5 years by using different sizes open-topped chambers（OTCs）.The major research result showed that：OTCs could effectively change micro-climate environment,with an obvious temperature rising ranging from 0.24 to 3.41℃.In the 1st year,the greatest aboveground biomass was in chamber B（202.01 g/m2）,the biomass of chamber A was the greatest one（414.56 g/m2） in the 5th year,and the analysis showed that the biomasses were obviously greater than those of other treatments（P0.05）.The change of average community height was comparatively more obvious,and it showed an annually rising trends in the same chamber;The result showed that the average plant community heights in 2006 were significantly greater than that of other years（P0.05）.Total community coverage showed an annually increasing trends too,and in the last year of the experiments,the total coverage approached or reached 100%.The sum of total species coverage in different treatment chambers have not obvious differences（P0.05）,while the differences of the sum of total species coverage between different years are significantly different（P0.001）;Duncan＇s new multiple range test reveals that：the sum of partial coverage of 2004 to 2006 are significantly greater than those of 2002 and 2003.Moreover,that of 2003 are significantly greater than that of 2002.These results revealed that quantity characteristics of plant community may be increased with temperature rising.