Abstract:

To understand the effects of the change of snow cover on the function of alpine meadow ecosystem, the plots were established in the middle part of Qilian Mountains in the northern Qinghai province, the snow cover of the alpine meadow was investigated using Snow Gage and Snow Fork analyzer, and the snow cover features were analyzed using correlation analysis and regression analysis. The results showed that the days with snow cover were quite different in different months in 2009 and 2010. In 2009, May had the most days with snow cover, March to April and September to October were followed, and the days with snow cover in February and June were short. In 2010, the days with snow cover were relatively less and mainly from January to June. In 2009, the difference of daily snow depth was less and snow depth was shallow from February to May, but the difference of daily snow depth was quite obvious from mid-May to the end of October. In 2010, snow depth was deeper from April to May and shallower from January to March, and daily snow depth was significantly different in snow cover days. In 2009-2010, the difference of daily snow density was small. Snow density was significantly positively related to snow depth (P<0.001), snow depth was significantly related to leaf humidity (P<0.001), the correlation between snow depth and solar radiation intensity was significant (P<0.001), and the correlation between snow depth and other climatic factors was not significant. In addition, the correlation between snow density and meteorological factors was not significant. Results indicated that snow cover of mountain alpine meadows in the northern Qinghai province is different in different years or months and the relationships between snow density and various meteorological factors is complex.

Key words: Snow cover, Alpine meadows, Climate change, Ecosystem function

摘要：

为了深入认识积雪变化对高寒草甸生态系统功能的影响，在青海祁连山中段山地建立了观测样地，以称雪器和Snow Fork分析仪进行了积雪观测，分析了山地高寒草甸中积雪的特征。结果显示：2009-2010年，山地高寒草甸不同月份积雪日数差异较大。2009年5月积雪日数较多，3-4月和9-10月其次，2月和6月较少；2010年积雪日数总体较少，集中在1-6月。2009年2-4月积雪深度浅、日差异较小，5-10月积雪深度日差异较大；2010年1-3月积雪深度相对浅，4-5月积雪深度深、日差异较大。2009-2010年，积雪密度日差异较小。积雪密度与深度呈极显著正相关（P<0.001），积雪深度与叶湿度极显著相关（P<0.001）、与太阳辐射强度显著相关（P<0.05），与其他气象要素相关性不显著，积雪密度与各气象要素相关性均不显著。结果表明，青海北部山地高寒草甸积雪变化年际间、月际间的差异较大，与气象因素的关系复杂。

关键词: 积雪, 高寒草甸, 气候变化, 生态系统功能