Abstract: In order to explore the relationship between natural pasture growth and meteorological conditions under the background of global warming in the ecological function area of northern shore of the Qinghai Lake, the influence of hydrothermal conditions on returning green date, growth height and yield of pasture were analyzed systematically based on meteorological and pasture observation data from 1997 to 2018. The results are as follows: (1) The influence of temperature on returning green date of pasture was significant in northern shore of the Qinghai Lake. The returning green date of pasture had significantly positive correlation with the first day of temperature higher than 0 ℃ and 3 ℃, the correlation coefficients were 0.590 and 0.567, respectively. (2) The growth rate of pasture had significant difference at different stages of growth, and the growth of pasture was the most vigorous from late June to mid-August. (3) The yield of pasture presented a significant ‘ladder’ variation characteristic in northern shore of the Qinghai Lake, and the average yield from 2010 to 2018 was 88% higher than that from 1997 to 2009. (4) The ≥0 ℃ accumulative temperature and precipitation during the growth of pasture presented an increasing trend in northern shore of the Qinghai Lake from 1997 to 2018, while the sunshine duration decreased, the warm and humid change characteristics were obvious, and the accumulative temperature of ≥0 ℃ during the growth of pasture was the key factor for the formation of pasture yield.

Key words: in northern shore of the Qinghai Lake, returning green date of pasture, pasture height, pasture yield, meteorological conditions

摘要： 为探究气候变暖背景下青海湖北岸生态功能区天然牧草生长发育与气候条件的关系，利用海北牧业气象试验站1997—2018年气象和牧草观测数据，分析了水热条件对牧草返青、生长高度和产量的影响。结果表明：（1）气温对青海湖北岸牧草返青具有重要影响，牧草返青期与≥0 ℃初日和≥3 ℃初日存在显著正相关，相关系数分别为0.590和0.567；（2）牧草生长期的生长速率在不同阶段存在显著差异，6月下旬至8月中旬牧草生长最为旺盛；（3）青海湖北岸牧草产量以2010年为界呈现出显著的阶梯状递增特征，2010—2018年比1997—2009年偏多88%；（4）1997—2018年青海湖北岸牧草生长期≥0 ℃积温及降水量总体呈现增加趋势，而日照时数则呈现减少趋势，气候的暖湿化特征明显，生育期≥0 ℃积温是青海湖北岸牧草产量形成的关键因子。

关键词: 青海湖北岸, 牧草返青期, 牧草高度, 牧草产量, 气象条件