Based on GIS,RS and the landscape analysis software,landscape changes in the middle and lower reaches of Houzhai River in Puding County of Guizhou Province from 1973 to 2004 were analyzed.The results indicated that pa...Based on GIS,RS and the landscape analysis software,landscape changes in the middle and lower reaches of Houzhai River in Puding County of Guizhou Province from 1973 to 2004 were analyzed.The results indicated that paddy fields and dry fields held a dominant status.In the change of landscape types,forest land reduced continually,dry fields changed complicatedly,and the mutual transformation among grass land,shrub land and forest land was obvious.The area of bare rock increased remarkably in the slope range between 10° and 35°.Artificially 'returning cultivation land into forests and pastures','reclamation by damaging forests and pastures',and natural ecosystem converse succession existed at the same time.Therefore,the whole landscape was in an unstable state.展开更多
Eight spatial structure types are determined through morphology, hydrogeology, hydrology and impulse response in karst districts, with the well studied Houzhai subterranean stream in Puding, Guizhou Province as a samp...Eight spatial structure types are determined through morphology, hydrogeology, hydrology and impulse response in karst districts, with the well studied Houzhai subterranean stream in Puding, Guizhou Province as a sample research area. These types contain peak forest basin, peak forest laterite platform, resurrected peak forest basin, old peak forest funnel depression, peak forest funnel, peak forest funnel depression, peak cluster valley and peak forest doline. In the area, each of them has its respective surface and subterranean structural feature, and morphology, hydrogeology, hydrology and impulse response as well. The difference of responses of subsurface system in different spatial structure types are obtained by time series analysis, frequency spectrum research and decline curve calculation of material current. According to the analysis of the aquifer feature, the upper reaches of suburfall stream is dominated by pipeline flow, the lower reaches is characterized by braided fissure flow drainage system and mixed characteristic exists in the middle reaches. The result of the impulse test shows that the large ascending range of stage in the test on swash condition is in fissure system. However, in pipeline type, especially in the subterranean stream where there is waterfall or incomplete fill of underground water, the ascending range of stage is one quantity level less than the impulse range of stage at some fissure types, showing that change range of stage can indicate the spatial structure characteristics of certain area upper the station. The main direction of karst geomorphic evolution there is positive course except in the west area. It can be seen that karst geomorphological evolution direction can change when discharge datum plane influences some part of a relatively large drainage. In certain time unit, the upper reaches are controlled by old datum plane and the lower reaches by new datum plane. Two opposite geomorphological evolution directions can exist in one drainage.展开更多
1 Introduction The Wuzhishan lead-zinc ore-concentrated area in Puding is located in the east of the Sichuan,Guizhou and Yunnan lead-zinc metallogenic domain,with the Youjiang-Nanpan River metallogenic province to the
文摘Based on GIS,RS and the landscape analysis software,landscape changes in the middle and lower reaches of Houzhai River in Puding County of Guizhou Province from 1973 to 2004 were analyzed.The results indicated that paddy fields and dry fields held a dominant status.In the change of landscape types,forest land reduced continually,dry fields changed complicatedly,and the mutual transformation among grass land,shrub land and forest land was obvious.The area of bare rock increased remarkably in the slope range between 10° and 35°.Artificially 'returning cultivation land into forests and pastures','reclamation by damaging forests and pastures',and natural ecosystem converse succession existed at the same time.Therefore,the whole landscape was in an unstable state.
文摘Eight spatial structure types are determined through morphology, hydrogeology, hydrology and impulse response in karst districts, with the well studied Houzhai subterranean stream in Puding, Guizhou Province as a sample research area. These types contain peak forest basin, peak forest laterite platform, resurrected peak forest basin, old peak forest funnel depression, peak forest funnel, peak forest funnel depression, peak cluster valley and peak forest doline. In the area, each of them has its respective surface and subterranean structural feature, and morphology, hydrogeology, hydrology and impulse response as well. The difference of responses of subsurface system in different spatial structure types are obtained by time series analysis, frequency spectrum research and decline curve calculation of material current. According to the analysis of the aquifer feature, the upper reaches of suburfall stream is dominated by pipeline flow, the lower reaches is characterized by braided fissure flow drainage system and mixed characteristic exists in the middle reaches. The result of the impulse test shows that the large ascending range of stage in the test on swash condition is in fissure system. However, in pipeline type, especially in the subterranean stream where there is waterfall or incomplete fill of underground water, the ascending range of stage is one quantity level less than the impulse range of stage at some fissure types, showing that change range of stage can indicate the spatial structure characteristics of certain area upper the station. The main direction of karst geomorphic evolution there is positive course except in the west area. It can be seen that karst geomorphological evolution direction can change when discharge datum plane influences some part of a relatively large drainage. In certain time unit, the upper reaches are controlled by old datum plane and the lower reaches by new datum plane. Two opposite geomorphological evolution directions can exist in one drainage.
基金funded by the national key basic research development program (2014 cb440905)key project of national natural science funds (41430315)
文摘1 Introduction The Wuzhishan lead-zinc ore-concentrated area in Puding is located in the east of the Sichuan,Guizhou and Yunnan lead-zinc metallogenic domain,with the Youjiang-Nanpan River metallogenic province to the
