中国生态环境过渡的一个重要地带

ON THE ECOLOGICAL SENSITIVE ZONE IN CHINA

本文揭示沿腾冲－黑河联线的地带不仅如胡焕庸早年提出是一条人口地理界线，而且是一条生态环境界线，更重要的是，腾冲－黑河线表征的方向，在历史时期表现为全球变化的特征方向。

n analysis to natural environment of China suggested that HU population line,whichlink up Tengchong and Heihe, is an important ecological boundary in China, the physical-based of the analysis are distributions of vegetable-soil system,natural disasters and climato-logical charateristics, the change of these distribution was been result to geomorphologicalregional change; in other words, the area near HU line is a ecological sensitive zone. Withphysical-geographical analysis,the sensitive zone is divided to three parts:<35°N,35─40°N,>40°N;second part includes Losses Liateau. The zone is a ectone. By applying histroical climate reconds,agricultural harverst recons and population distri-bution analysis, we have shown the HU Line characterazed a group directions, which showesthe global climate and environment change in China;and in warmer periods,the sensitive zonealong HU line westward move,after A.D. 1260 HU Line is sensitive zone. This paper suggest that we must distinguish sensitive zone,critical zone(region)and eco-tone. Sensitive zone is sensitive respond climatical variation, critical zone is a delaied regionaginst about environment change in present,it may be critical or sup-critical system,and anydestroy means great damage,both were called ecotone.