Ecological Security Evaluation And Landscape Pattern Optimization Of Huanggang Dabieshan UNESCO Global Geopark

Ecological security is an important component of national security,which concerns the overall situation of national development.As the eco-environmental issues has become one of the important factors affecting national security and restricting the sustainable development of China’s economy and society,it has become a research consensus to carry out ecological security research and improve the level of ecological security.As a unique natural area,UNESCO Global Geopark(UGGp)has played an irreplaceable role in protecting geoheritages and natural ecological environment,popularizing geological knowledge,developing tourism and promoting local economic development.Therefore,the research on ecological security and landscape pattern optimization of UGGp is of great significance for achieving the coordination and sustainability between ecological security maintenance and regional economic development of UGGp.Huanggang Dabieshan UGGp is located at the southern foot of the Daie Mountain and in the northeast of Huanggang City,Hubei Province.The unique geographical location and climatic characteristics breed a variety of natural organisms.With the development of regional social economy and the incease of population,human activities are constantly consuming land resources,resulting in excessive cultivation,deforestation,steep slope cultivation,and over-exploitation tourism development occur from time to time.The contradiction between the protection and development of UGGp is increasingly prominent.The increase of negative impacts on regional ecological environment has put enormous pressure on regional ecological protection.Therefore,based on the land use change of Huanggang Dabieshan UGGp,this thesis used land use data from 2000,2005,2010,2015 and 2018 to analyze the spatial and temporal evolution of land use and landscape pattern in the study area.The UGGp ecological security evaluation model was built based on the "pressure-state-response"(PSR)model,and the spatial and temporal change characteristics of the ecological security level was scientifically evaluated.The FLUS multi-scenario simulation model was used to predict the dynamic changes of landscape patterns in the study area in 2036 based on the data from 2018,and the results of different scenarios were compared by landscape index analysis.The ecological security pattern was constructed based on the optimum result of multi-scenario simulation,and the spatial layout planning and suggestions was proposed according to the characteristics and distribution of resources in Huanggang Dabieshan UGGp.The research ideas and methods of this thesis has followed the concept of UGGp protection and sustainable development.The research results are of great theoretical and practical significance for scientifically guiding the construction and management of UGGp and the development of geotourism activities,achieving the coordination and unity of protection and development,preventing ecological risks,maintaining the security and stability of the regional ecosystem,and promoting the sustainable development of UGGp.The main conclusions of the article are as follows:(1)Forest land and cultivated land are the main types of land use in the study area.During 2000 to 2018,the proportion of forest land area has reached 59%,while the proportion of grassland and wetland area was relatively small and continued to decrease.The area of construction land was continuously expanded and increased by 68.1%.The main pattern of land use change in the study area during the study period was the mutual conversion of cultivated land,forest land and construction land.The mian change in transfer-out of land use was cultivated land,which was converted to forest land and construction land.The maim change in transfer-in of land use was forest land,which was mainly converted from cultivated land and grassland.(2)During 2000 to 2018,the degree of landscape fragmentation in the study area was increasing and the connectivity of landscape was decreasing.The complexity and heterogeneity of the internal landscape structure increased.Forest land has always maintained a relatively high degree of dominance,with a very small range of change.The cultivated land patches changed most acutely,which reached the highest fragmentation degree.Wetland patches continued to decrease,with the most complex shape and the lowest aggregation.Construction land expanded rapidly,and the patches are gradually concentrated and contiguous.From a spatial perspective,there was an increase in landscape diversity and fragmentation in the northwest,southwest,and southeast regions due to the high intensity of land use and frequent conversion between different types of land use.In the northeast region,forest land has always occupied a leading position as the dominant patches,resulting in a high degree of landscape aggregation.(3)The study area has been strongly affected by external disturbances for a long time,posing a threat to the safety of the ecosystem,and the ecological function was relatively unstable.During the whole study period,the number of townships with ecological security state below the critical level was always more than those with state above the critical level.The average ecological security index of the Geopark was fluctuating and increasing,remaining in a state of risk(level II)and sensitivity(level III).The ecological security level was in a fluctuating state,with level I and level II occupying the vast majority of the study area during the whole study period,accounting for about63% of the total area.The area of the highest ecological security level(VI)had the lowest proportion of the study area,which was only about 2%.(4)The ecological security of the study area showed obvious spatial clustering characteristics,and its spatial-temporal differentiation pattern was closely related to factors such as land use types and human activities.The areas with high ecological security levels were mainly located in alpine woodlands with higher elevation and better vegetation coverage,mainly in the core ecological areas of the Geoparks such as Guifengshan,Bodaofeng,Tiantangzhai,Wujiashan and Tiantang Lake,which were also the main distribution area of nature reserves.They were constrained by national policies and local regulations,resulting in a relatively stable ecosystem structure and landscape pattern and strong ecological restoration ability.The development and construction of the Geopark has little impact on them.Areas with low ecological security levels were mainly distributed in urban agglomeration areas,township settlements,and main transportation roads with low altitude,gentle slopes,and suitable for production and living.The land use types were mainly cultivated land and construction land,which were greatly affected by human activities.(5)The multi-scenario simulation results of land use change in the study area showed that under the ecological protection scenario,the area of ecological land such as forest land,grassland,water area and wetland would increase slightly.Compared with natural development and cultivated land protection scenarios,adding ecological constraints could regulate and control the the overall landscape pattern regularity and protect the core ecological space more effectively,while it could also ensure that production and economic development are not excessively restricted.The setting of this scenario followed the concept of the coordination and unification of the “Protection” and“Development” of UGGp,which would contribute to the sustainable development of UGGp.Therefore,the land use pattern under the ecological protection scenario was relatively better than other simulation results.(6)Based on the simulation result of the ecological protection scenario,the future ecological security pattern was constructed,the ecological corridors were delimited,the important ecological nodes were selected,and the spatial layout planning and countermeasures were put forward,which would help improve the connectivity of landscape functions and the stability of landscape structure in the study area,strengthen the landscape ecological function,and ultimately maintain the regional ecosystem security.The research results will provide data support and scientific reference for the sustainable development of UGGp.