Ecological Vulnerability Evaluation And Conservation Management Strategies Of South China Karst World Heritage Sites

The South China Karst World Heritage Sites possess unparalleled natural beauty and geomorphological value,and the IUCN has clearly proposed to focus on the ecosystem services of the World Natural Heritage Sites.Heritage tourism is gradually becoming a cash cow for local economic development,and World Natural Heritage should be protected as the most valuable treasure of mankind.Ecological vulnerability evaluation is an important way to achieve ecological conservation of heritage sites,and is important for maintaining the integrity of the natural landscape of heritage sites and tourism development.Based on the theories of geography,ecological economics,heritage conservation,coordinated human-land development,ecological-economic balance,and synergy between heritage development and ecological conservation,this paper addressed the scientific issues of ecological vulnerability characteristics,spatial and temporal evolution of ecological vulnerability and conservation management in the South China Karst World Heritage Sites,and selected Shibing Dolomite Karst and Libo-Huanjiang Limestone Karst as the study areas in the karst region of Guizhou,which represent the overall structure of the ecological environment and the basic status of conservation management in South China Karst World Heritage Sites.Based on the fieldwork and data collection of the heritage sites,this paper used model construction,hierarchical analysis and entropy method to systematically study ecological pressure,ecological state and ecological response,focusing on elucidating the connection between natural environmental factors,anthropogenic activity factors and ecological vulnerability,constructing an ecological vulnerability evaluation index system fitted to the South China Karst World Heritage Sites,revealing the ecological vulnerability characteristics and dynamics as well as their mechanisms,and proposing ecological protection and management strategies to provide scientific references for ecological environmental protection and sustainable development of tourism resources in the South China Karst World Heritage Sites.(1)From 2010 to 2020,the score of ecological pressure in the Shibing heritage site gradually decreased from 0.07 to 0.04,whereas that of the Libo-Huanjiang heritage site increased from 0.24 to 0.26,mainly due to the higher pollution pressure and tourism pressure within the Libo-Huanjiang heritage site.From 2010 to 2020,the score of pollution pressure rose from 0.06 to 0.08 and the score of tourism pressure rose from 0.10 to 0.013 in the Libo-Huanjiang heritage site.The contribution of pollution pressure and tourism pressure to the overall score of ecological vulnerability increased.Fertilizers and pesticides used by residents around the heritage sites have become important factors in environmental pollution,flowing to the heritage sites and their surrounding areas by the water cycle,leading to the death of vegetation,reduction of vegetation cover,and threats to biodiversity.Tourism development activities increase the burden on the ecological environment of heritage sites,the construction of tourism facilities damage to surface vegetation is difficult to repair,the hardening of the surface of tourism roads makes the soil less permeable and breathable and reduces the infiltration rate of rainwater,and it is easy to cause water accumulation in low-lying areas during the rainy season,which poses a threat to the growth of vegetation.(2)From 2010 to 2020,the score of ecological state in the Shibing and Libo-Huanjiang heritage sites showed a gradually decreasing trend,decreasing from0.30 to 0.18 and from 0.18 to 0.05 in the Shibing and Libo-Huanjiang heritage sites,respectively.Vegetation,land and climate are visual factors reflecting the condition of ecosystems,and the impact of human activities on the ecological environment involves the entire geosphere.From 2010 to 2020,the scores of climate state,land state and vegetation state in the Shibing and Libo-Huanjiang heritage sites all showed a decreasing trend,indicating that the ecological environments and the stability of ecosystems in the heritage sites increased.However,the score of soil state in the Shibing and Libo-Huanjiang heritage sites did not change significantly,indicating that the soil conditions in the heritage sites were relatively stable.(3)From 2010 to 2020,the score of ecological response in the Shibing and Libo-Huanjiang heritage sites decreased gradually,decreasing from 0.22 to 0.10 and from 0.12 to 0.06 in the Shibing and Libo-Huanjiang heritage sites,respectively.From2010 to 2020,the scores of management measures and vegetation restoration showed a decreasing trend,indicating that management agencies have strengthened and paid attention to the protection and management of the ecological environment in heritage sites.When the external disturbance exceeds the maximum capacity of the ecosystem,the self-regulating ability of the ecosystem would decrease and the fragility of the ecological environment becomes apparent,making it difficult to return to its original state.Without the intervention of anthropogenic conservation measures,the ecological environment may continue to deteriorate.The amount of tourists in each scenic spot within the Shibing and Libo-Huanjiang heritage sites varies,and the ecological environment has been damaged to varying degrees.Tourist attractions should be strictly managed and protected,regularly conducting ecological environment evaluation,and implementing a rotating opening system to allow ecological restoration in attractions with high degree of ecological vulnerability.(4)From 2010 to 2020,the ecological vulnerability indexes of both the Shibing and Libo-Huanjiang heritage sites gradually decreased,showing that the ecological vulnerability index of the Shibing heritage site decreased from 0.59 to 0.32 and the ecological vulnerability index of the Libo-Huanjiang heritage site decreased from0.55 to 0.37.The degree of ecological vulnerability both showed a moderate-light-light transformation,indicating that ecological vulnerability decreased and ecological environment improved in the Shibing and Libo-Huanjiang heritage sites.Ecological vulnerability is an inherent property of the ecosystem,related to its regulatory capacity and external disturbances,and gradually manifests under certain pressure.The South China Karst World Heritage Sites present different levels of vulnerability characteristics due to their inherent vulnerability and external interferences.Based on the research and analysis of the ecological vulnerability characteristics,dynamic evolution and its mechanism in the Shibing and Libo-Huanjiang heritage sites,the ecological conservation management strategies of Shibing model,Libo model and Huanjiang model are proposed.In the future,the ecological vulnerability of each functional zone within the heritage sites can be studied by means of 3S technology to further optimize the evaluation index system and research methods in the South China Karst World Heritage Sites and improve the ecological protection strategy formulation for different functional zones in the South China Karst World Heritage Sites.