Barrier-corridor effect of longitudinal range-gorge terrain on monsoons in Southwest China
西南纵向岭谷地形对季风的“通道—阻隔”作用

Topographic pattern has important impacts on atmospheric circulation and regional climate.The special terrain of Longitudinal Range-Gorge Region(LRGR) in Southwest China has a "corridor-barrier" effect on monsoons circulation,which led to the redistribution of surface hydrothermal pattern and is the main driving force of the formation and evolution of the ecosystems.Previous studies showed that LRGR was influenced by the combined effect of the Indian monsoon and the Pacific monsoon,which meet at the Ailaoshan mountain ranges.The Ailao Mountains are an important geographical dividing line.In this study,based on proofs of the atmospheric circulation,moisture transport,regional climate,runoff,and plant stable oxygen isotopes compostion,we found that LRGR is affected mainly by the Indian monsoon.The Pacific monsoon only affect this area in August,and the influence is not significant.Under the terrain "corridor-barrier" effect,surface water vapor,precipitation and runoff in LRGR showed significant zonal differences and meridional extension;crowd circulation,moisture transport,regional climate and river runoff.The atmospheric precipitable water,precipitation and stream flow present an apparently different pattern between the west and east sides of Ailao Mountains.The environmental differences are the results of the hydrothermal redistribution by the special terrain,which are the "barrier" and "corridor" effects of the LRGR.These differences are not the results of geographical zonality,but the results of non-zonality.The "corridor-barrier" effects of the longitudial range-gorge on monsoons result in the spatial differences of the geographical elements and the associated ecological effects.