气候变暖对青海高原地区植物物候期的影响

将青海高原划分为东部农业区、环青海湖区、三江源区和柴达木盆地4个地区,根据1983—2007年各个地区气象台站所观测的气象资料,利用统计学方法,分析了不同地区植物物候期对气候变化的响应。结果表明:东部农业区、环青海湖区、三江源区和柴达木盆地年平均气温均呈上升趋势。在气候变暖背景下,东部农业区、环青海湖区、三江源区植物返青普遍期呈提前趋势,柴达木盆地返青普遍期呈推迟趋势,4个地区黄枯普遍期均呈延迟趋势,植物生长季延长。年降水量各地变化趋势不同,年降水量和阶段降水对植物生长关键期的变化有一定影响,但与气温相比其影响相对较小。

Influences of Climate Warming on Plant Phenology in Qinghai Plateau

Long period data observed at selected meteorological stations are analyzed to investigate the response of plant phonology to climate warming in Qinghai Plateau. The Plteau is divided into eastern agriculture region, around Qinghai Lake region, source of three rivers and Qaidam Basin, with their representative areas of Huangyuan, Menyuan, Qumalai and Delingha, and the analysis period is 1983—2007, 1987—2007, 1997—2007 and 1987—2007 respectively. Monthly and annual mean temperature, precipitation, plant development period and other related data are analyzed statistically, showing that annual temperature increases in all of the 4 regions with the ratio of 0.61℃/10 a, 0.59℃/10 a, 1.52℃/10 a, 0.62℃/10 a respectively. Annual precipitation of around Qinghai Lake region shows a decreasing trend, and the value is-11.58 mm/10 a. Annual precipitation of eastern agriculture region, source of three rivers and Qaidam Basin increases by 0.86 mm /10 a, 107.37 mm /10 a and 12.95 mm /10 a respectively. The date of turning green in Qaidam Basin region has delayed by 8.2 d, but in eastern agriculture region, around Qinghai Lake region and source of three rivers it is 8.6 d, 10.5 d and 9.8 d earlier than before. In these 4 regions the flowing stage are respectively 3.2 d, 7.8 d, 1.7 d and 10.9 d earlier. The yellow stage is respectively 6.5 d, 16.2 d, 6.6 d and 6.2 d later, so the plant growth stage is extended in the eastern agriculture region, around Qinghai Lake region and the source of three rivers, but the plant growth stage is shortened a little in Qaidam Basin. The changing tendency of turning green data and yellow stage is found well correlated with annual mean temperature. There are many factors affecting the flowing of plant, so the correlation between plant flowing and mean annual temperature is less significant. The annual precipitation and stage precipitation have some influences on key periods of plant growing, but the influences are less important compared with the temperature.