Relationships Between the Spatial Distribution of Karst Land Desertification and Geomorphology,Lithology,Precipitation,and Population Density in Guizhou Province
Relationships Between the Spatial Distribution of Karst Land Desertification and Geomorphology,Lithology,Precipitation,and Population Density in Guizhou Province
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发表时间：
2013
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通讯作者：
Zhang Siyu
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作者：
Zhang Siyu
研究揭示了贵州喀斯特退化景观的空间分布特征，认为退化喀斯特景观的空间分布与地表物质和气候(降水)条件有很好的相关性，但与现今人类活动(人口密度)的相关性不大。(1)贵州喀斯特地貌类型的空间分布以化学侵蚀为主，与贵州纯碳酸盐岩有较好的相关性，峰丛地貌主要分布在威宁-毕节-贵阳-凯里线以南，年降水量为≥1200 mm，随着降水量的增加，出现较多的塔状岩溶丘陵。在贵州西北部，年降水量为≤1100 mm，以化学侵蚀为主。在威毕线以北，毕节-贵阳-凯里线以北以化学-河流侵蚀为主的区域，多为正常丘陵，峰丛较少。(2)贵州喀斯特土地沙化程度与喀斯特地貌类型密切相关，与人口密度关系不大。贵州中部人口密度在300~400个/km2的县，喀斯特土地沙化程度不如贵州西南部人口密度在200~300个/km2的县和黔南人口密度在100~200个/km2的县。森林破坏是贵州喀斯特土地荒漠化的主要驱动力。除荔波县茂兰公园等少数天然喀斯特森林外，原始天然林在历史上遭到了大规模破坏，无论是在人口密度高的地区，还是在人口密度相对较低的地区。由于次生植被的恢复程度在很大程度上取决于坡面、坡面和坡面的土壤条件喀斯特土地荒漠化严重程度的空间变化主要受地面土壤和岩石组成的控制，坦率地说，是由裸露的岩石丘陵地所占比例控制的。
This study reveals the spatial distribution of degraded karst landscape in Guizhou and concludes that it is well related to ground substance and climate(precipitation) conditions,but not well to current human activities(population densities).It is expressed as follows:(1) The spatial distribution of the geomorphologic type,dominated by chemical erosion,is well related to pure carbonate rocks in Guizhou,where peak cluster landforms are mostly distributed in the area south of the Weining-Bijie-Guiyang-Kaili line with the annual precipitation of ≥1200 mm and more tower karst hills appear as precipitation increases.In the northwest of Guizhou with the annual precipitation of ≤1100 mm,dominated by chemical erosion,north of the Weining-Bijie line,and in the area,dominated by chemical-fluvial erosion,north of the Bijie-Guiyang-Kaili line,there are mostly normal hills with few peak clusters.(2) The karst land desertification severities are well related to karst landform types,but not to population densities,in Guizhou.In the area south of the Weining-Bijie-Guiyang-Kaili line,where peak cluster landforms develop well,karst land desertification in the counties of central Guizhou with population densities of 300~400/km2 is not severer as in the counties of Southwest Guizhou with population densities of 200~300/km2 and in the counties of South Guizhou with population densities of 100~200/km2.Destruction of forests is the main driving force to karst land desertification in Guizhou.Except for a few natural karst forests,such as the Maolan Park in Libo County,the original natural forests were massively destroyed during the history,either in the areas with high population densities or in the areas with relatively low population densities.As the restored extent of secondary vegetation depends largely on the soil conditions on hill slopes,the spatial variation of karst land desertification severities is mainly controlled by soil and rock compositions on the ground,frankly speaking,by the proportion of bared rock hill land.