主要气候因子对天然草地产草量的影响评价

Evaluation of Main Climatic Factors Effecting on Grass Production of Natural Grassland

为了解影响青海省共和盆地天然草地产草量的主要气候因子,以天然草地产草量为参考数列,以牧草生长季4-9月≥0℃积温、平均温度、降水量、日照时数、水热综合配合(降水量与气温的比值)以及上年度9-11月的降水量等气候因子做比较数列,用主成分分析法和灰色关联度分析法对影响青海省天然草地产草量的气象因子进行了综合评价。结果表明,温度、水分、光照3个综合因素对牧草生长具有协同作用,在水分、光照充足的情况下热量因子对牧草产量起着主要作用。主成分和灰色关联度2种评价方法均可作为评价天然草地产草量的影响因子,二者评价结果基本一致。

Influence factors on grass production of natural grassland in Gonghe basin of Qinghai province were analyzed by using theories of principal component and gray correlation. The grass production of natural grassland was used as reference number series. And compared series included accumulated temperature, average temperature, precipitation, sunshine hours and synthesis of hydrothermal （ratio of precipitation and air temperature） of ≥0°C during April to September of grass growth season, and climatic factors such as precipitation from last September to November. The results show that there is a synergistic effect between grass growth and a synthetic factor combining temperature, moisture and illumination. Factor heat performs a main effect for the grass production when there are enough moisture and sunshine. With similar evaluation results, both evaluation methods of the principal component and the gray correlation could be used to estimate the influence factors of grass production in natural grassland.