| In June, 2007, Libo was listed as a world natural heritage for its typical cone karst landform. But the research to Libo cone karst is deficient. From the point of view of geomorphology and according to the idea of system theory, abundant information and data have been obtained directly or indirectly through consulting many worldwide karst experts, many times'field survey, measuring and calculating in maps and literature collecting. The research was carried out by using geography comparison method and synthetic analysis method, combining cone karst landforms features in Libo with world natural heritage evaluation criterion (viii), combining theory with practice, combining qualitative with quantitative, and combining periphery and sample areas, on developing features of Libo cone karst; measuring and analysis of cone karst morphology and features in typical sample plots; the selecting of sites in the world which can be compared with Libo cone karst and comparative analysis of them. The main conclusions of the thesis are as follows:(1) It is shown by calculating and analyzing the morphology of Libo cone karst that, the spatial geometry morphology of cone karst appears in ellipse-shaped and nearly taper-shaped cones with symmetrical slopes and plumb lines of summits; the relative height of cones is in direct ratio with the diameter; the morphogenetics of the tropical and sub-tropical karst landform shown by the ratio of the relative height of cones and the diameter lies between Organos type and Sewu type in the five plots; the average slope of cone peaks in the five plots is 45.5°, shown in the profile of the peaks. The average symmetry is 1.73; the planar spread of the cone summits is different, which is relatively uniform in Pobao, cluster in Banzhai and between the two in other three plots; the area of polygonal depressions become bigger along Wangmeng to Dongduo to Banzhai to Dongla; among the five plots, the planar structure of the depressions are beehive-shaped polygon in Pobao, Dongduo and Banzhai; the average sides are 6.3; the density of the depressions is small, with the average value 2.25.(2) Libo has a more special evolution environment. It lies in the transitional zone between Guizhou plateau and Guangxi low land. The matching condition of rain and heat is good. The water system develops well and the primary forests are well protected. Ancient, hard, extensive and continuously distributed thick dissolvable rocks developed. The impact of neo-tectonic movement on it is strong.. (3) Libo has a very complex cone karst geological evolution process. It reflects the fact that multi-stage uplifts have happened in the thick carbonate rock. It also reflects the impact of the global change of atmosphere circumfluent on the development of the cone karst. It meanwhile reflects important on-going geomorphology evolution process.(4) Libo has typical cone karst individual shapes. The line of the slope is influent, the slope is 45.5°, the summit is sharp, the bottom is rotundity or nearly rotundity, and the cone body is very hign. The depressions are deep and close, different in sizewith polygonal features and cylinder, funnel, or basin shapes. It is obvious that the sink holes distribute in clusters. Most of the depressions have four, five or six sides, and the average sides are 6.3, reaching the best and most stable situation. Moreover, long, deep multi-layer cave systems develop in Libo, forming an integrated surface-underground karst system.(5) Libo has the relatively complete cone karst assemblages. The shapes of cone karst are very diverse. Almost all the typical cone karst shapes can be seen in about dozens of square kilometers.Therefore, Libo is an outstanding example representing major stages of Earth's history, including the record of life, significant ongoing geological processes in the development of landforms, or significant geomorphic or physiographic features.
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