【作者】 彭建；

【导师】 杨明德； 梁虹；

【作者基本信息】 贵州师范大学 ， 自然地理学， 2002， 硕士

【摘要】 石林是一种稀有性的喀斯特地貌形态，是指石灰岩在长期的喀斯特作用下，沿节理溶蚀而形成的高5m以上的石柱组成的林状地貌景观，国外称为针状喀斯特或剑状喀斯特。石林的成因及发育演化问题引起了国内外喀斯特学者的关注，他们从地质、气候、构造、水文过程、土下溶蚀过程、地貌成因类型、发育年代、发育历史和古地理环境以及微形态的生物作用过程等方面对石林的形成发育进行了宏观和微观的研究，并提出了相应的发育演化模式，但多侧重于单一方面的研究。 作为一种喀斯特地貌形态，石林总是分布于特定的流域中，它的形成和发育演化与其所在流域的整体演化必然存在着密切的联系，石林的出现、消亡是和流域地貌的发育演化阶段相关的。因此，可以把石林放在一个特定的时空边界地域条件下，运用喀斯特水文地貌学的理论和方法，以流域的物质能量的转移、平衡、变异为基础，从流域的基面——径流——形态的相互响应过程上来揭示石林形成发育机制和演化模式，从一个新的、系统的角度去认识石林的发育规律。 正是基于这种认识，本文以我国石林发育最完美的路南石林为研究对象，研究了巴江喀斯特流域的水文地貌结构特征、石林的形态类型及其空间分布特征；探讨了石柱顶部的剥蚀速率(A)、表土剥蚀速率(S)、土下溶蚀强度(C)及其组合对石林发育的影响，提出并论证了路南石林发育的“三重剥蚀”机制；通过对石林发育必备条件的剖析，以及对巴江喀斯特流域演变阶段的定量研究、水文地貌系统的空间耦合分析，探讨了巴江喀斯特流域的演变与路南石林发育间的关系，并结合该流域的演化史，提出了巴江喀斯特流域演变与路南石林发育的模式。 在“三重剥蚀”机制中，若A＜S＜C，石柱的可见高度和实际高度会不断增高，同时，石柱的根部的土层会增厚，其土下部分的高度也会不断增大。若A＜C＜S，说明石柱的实际高度在增加的同时，其可见高度也在增加，但土层会变得越来越薄，最终当底土被完全剥蚀掉后，气下溶蚀和土下溶蚀的差异消失，此时A接近于C，石柱的实际高度将停止拔高或极缓慢增长，并在各种物理、化学风化的作用下而变得日益矮小。若S＜A＜C，石柱的可见高度将趋于变矮，但驱动石林发育的土层厚度将会增大。对路南地区的A、S、C三因子的综合研究表明，在现代自然条件下，石林的实际高度仍以15.77mm／ka的速度在拔高，石林的可见高度现正以639.6mm／ka的速度增加；促使石林增长拔高发育的源动力——土壤正以623.83mm/ka的速度快速变薄，说明虽然目前石林的高度仍在增加，但其发育的最佳时期己经过去。 同时，研究也表明，土壤CO:的最大浓度主要出现在土下60一120cm，土壤水的含量在土下60一80cm处也较大，由此决定了土下最大溶蚀强度主要分布在土下150cm内，包气带强溶蚀循环带的下限约在土下IOm处。因此，在厚达数百米的路南群的覆盖之下，是不可能发育石林的。现代路南石林的发育是应始于晚第三纪，是老第三系地层剥蚀到一定程度时的产物。由于包气带强溶蚀循环带的深度有限，纯粹于土下发育的石牙、石林，其高度一般不会超过10m，现在我们所见高度在10m以上的高大石林，是在后期厚层覆盖物的剥蚀过程中增长拔高的。由于土下(尤其是酸性红土)溶蚀过程在石林发育中的重要地位，有广布、厚层风化残积土分布的老年期准平原是石林发育的理想场所，容易形成大面积的石林分布区。此外，虽然喀斯特水文地貌学的理论、方法源于贵州喀斯特高原的研究，但在揭示路南石林的发育演变规律的研究中得到了较好的应用，说明了其在解决贵州喀斯特高原以外其它类型喀斯特地貌发育问题中的适用性。更多还原

【Abstract】 Stone forest, which is a kind of rare karst geomorphology and called as pinnacle karst in other countries, refers to the forest-like landform composed of the stone pillars more than 5 meters high and resulted from longtime dissolution of limestone along joints. The origin and development of stone forest has attracted many karst researchers home and abroad, and they have done some macroscopical and microscopical studies on stone forest in terms of such conditions for its development as geology, climate, hydrological process, sub-soil corrosion, geomorphological types, history of development, paleo-geographical enviroment and biological effects etc, and put forward some development models, however, most of the studies just pay their attention to some single aspects of the problem.As a kind of karst geomorphology, stone forest is always distributed in a kast drainage basin , its development is inevitably related to evolution of the whole catchment. Therefor, in the light of theory and methods of karst hydrogeomorphology and the knowledge of transformation, balance and variation of matter and energy in karst drainage basin , we can examine stone forest within a specific scope of time and space, and reveal the mechanism and the development model of stone forest with the help of the principle of the mutual response processes among base-level, water flow and forms.Just based on the understanding above, the paper, with a special reference to the Lunan stone forest which is the best developed one in China, discusses the hydro-geomorphlogical structure of the Bajiang river, geomorphological types and spacial distribution feature of the stone forest, and studies the erosion rate on the top of stone forest, soil erosion rate, sub-soil dissolution rate and their combined influences on the evolution of stone forest, furtherly brings forward and demostrates the "tri-level erosion" mechanism for the development of stone forest. Then , by the comprehensive analysis of essential conditions for stone forest development, and the quantitative study on the evolution phases of Bajiang karst catchment and the spacial coupling analysis of its hydro-geomorphological system, the paper studies the relationship between the evolution of Bajiang karst drainage area and the development of stone forest, and, combined with the evolution history of the catchment, puts forward a model concerning the relationship between the evolution of Bajiang karst catchment and stone forest development,In the mechanism of "tri-level erosion", if A< S<C, the visible and actual height of stone pillars will keep on increasing, meanwhile, soil layer among stone pillars will become thicker and thicker, so the the height of stone pillars’ root will become higher and higher, too. If A<C<S, itmeans that the visible height of stone pillars will increase.as its actual height increase; however, the soil layer will become thiner and thiner, and when the soil is eroded up in the end, the differences between sub-aerial and sub-soil dissolution will disappear, then, A will be proximately equal to C, the actual height will stop increasing or increase very slowly, so the so the stone forest will become shorter and shorter with various kinds of chemical and physical wheathering. if S<A<C, the visible height of stone pillars will trend to be shorter, but the soil layer, which drives stone forest to develop continually, will become thicker. Through the study of three factors of A, S, C in Lunan area, we have found that, under the modem natural conditions, the actual height of stone pillars is still increasing at the rate of 15.77mm/ka, and their visible height 639.6mm/ka, moreover, soil layer which is one of the most important driving forces for the heightening of stone forest is quickly becoming thiner and thiner at the speed of 623.83mm/ka. All the facts above indicate that the best development era of Lunan stone forest has passed by, although the height of stone pillars is still increasing at present.Meanwhile, The study also shows that the maximal concentr更多还原