According to the analysis of topographic characters

climate types

the change trend of both temperature and precipitation

use of the technique of RS and GIS

the spatial distribution pattern of macro-scale ecological background were discussed.Conclusion was made as follows:(1) On the countrywide scale

the research area was a part of 6 topography domains and 11 topography regions.(2) There were 7 types of climate in the research area.The East Region was prevailingly controlled by the meso-temperate forest-to-steppe climate

while the Middle Region

by the warm-temperate continental forest-to-steppe climate

and the West Region

by the temperate cold alpine grassland climate.(3) In the recent 40 years

climate change trends varied from region to region.In the East Region it showed mainly a tendency of warm-humid type

while in the Middle Region

a cold-arid type and in the West Region

back to a warm-humid type.(4) According to the geomorphic and climatic characteristics

the research area was divided into three regions: East North-by-Northeast China Farming-pastoral Zone(East Region for short)

Middle Farming-pastoral Zone in Shanxi

Shaanxi

Ningxia and Gansu Provinces(Middle Region for short) and West Farming-pastoral Zone in Gansu and Qinghai Provinces(West Region for short).