|
|
|
| Comparison of mechanism between collapsing erosion in China and overseas badland erosion |
| Jiang Chao1, Chen Zhibiao1,2, Chen Zhiqiang1,2 |
1.College of Geographical Science, Fujian Normal University, 350007, Fuzhou, China;
2.Key Laboratory for Subtropical Mountain Ecology (Ministry of Science and Technology and Fujian Province funded), 350007, Fuzhou, China |
|
|
|
|
Abstract As a unique erosive landform in China, collapsing hills occur mostly in Yangtze River Basin, Pearl River Basin and southeast coastal river basins, while badlands are distributed largely in mountainous catchments ( Pyrenees ), the Negev Desert and Apennine Peninsula along the Mediterranean. Both of them are severely erosive degradation patterns around the world and become obstacles to regional rehabilitation as well as human development. The research progress of mechanism between collapsing erosion and badland erosion in the past three decades is reviewed through literature analysis in this paper. The similarities between them are as follows: 1) both of them are driven by the combination of hydraulic power with gravity, which destroy the structure and stability of rock layer as a result; 2) their surface shapes are distinctive, characterized by the detachment of the slope and gully, and alluvium-colluvium deposition along down slope; and 3) the content of organic matters is extremely low, together with scarcity of mineral nutrient and lack of vegetation. The ifferences between them are: 1) the dissimilarities in climatic type, geological structure, topographical features, vegetation conditionsand the extent of anthropogenic impact are remarkable; 2) the collapsing wall and its red soil layer are typical features to distinguish vertical section of collapsing hills and badlands; and 3) physical and chemical properties, exchangeable ion activity, dispersive characteristics and mechanical traits are quite different between collapsing hills and badlands. Future research on mechanism of collapsing erosion should pay more attention to the micro-scale fields such as elemental composition, spatial distribution and exchangeable ion activity.
|
|
Received: 25 March 2014
|
|
|
|
|
|
|
|
|
