环青海湖地区草地蝗虫成灾状况与气候条件的关系

Preliminary Study on the Relationship between the Grasshopper Plague Formation and the Weather Conditions in the Areas around the Qinghai Lake, China

本文以 1988 - 1998年蝗灾记录资料和 1997- 1999年实地调查资料为基础 ,初步探讨了环青海湖地区草地蝗虫数量的空间分异特征 ,并利用近十年来刚察县气象资料 ,定性分析了不同年份灾情状况与气温、降水之间的关系。结果表明 ,6 -

Based on the recorded data during 1988～1998 and the surveyed data collected during 1997～1999, this paper discusses the spatial differentiation of grasshopper population in the areas around the Qinghai Lake, China. Furthermore, the relationship between the grasshopper plague situation and air temperature and precipitation in the different years is qualitatively analyzed. The main conclusions include:① The distribution and the spatial differentiation of the population of grasshoppers are evidently affected by topographical conditions, such as elevation, slope facing and gradient, because these factors can change the local climate. In the areas around the Qinghai Lake, the statistical result shows that the grasshoppers mainly distribute in a zone of 3,200～3,450 m a. s. l., especially in a zone of 3,250～3,350 m a.s.l., and the conditons of south-facing slope are more suitable to grasshoppers to inhabit than that of north-facing slope. ② The brood and nymph stages of the prime grasshopper species (Chorthippus dubius and Chorthippus fallax ) are in the period from June to July, and the temperature and precipitation during this period have more obvious influence on the intensity of grasshopper plague. The intensity of grasshopper plague is greatly decided by aridity index, when the aridity index is moderate or slightly higher, there is a great possibility of occurring a serious grasshopper plague; when it is very high, a moderate grasshopper plague may occur; and when it is low, the intensity of grasshopper plague is low universally.