| With the rapid urbanization and rapid economic and social development,high-intensity development and utilization activities form frequent disturbance to natural ecosystems,serious affect climate regulation,hydrologic regulation,soil conservation and biodiversity maintenance ecosystem service supply,it poses a certain threat to the regional ecological security and sustainable development.Chengdu-Chongqing Twin City Economic Circle plays a crucial role in the construction of the Yangtze River Economic Belt and the ecological barrier in the upper reaches of the Yangtze River.However,industrialization and urbanization,to some extent,lead to the contraction of natural ecological space and the degradation of ecosystem service function in this region,so it is urgent to carry out research on the optimization of ecosystem service and ecological network layout.This paper takes the Chengdu-Chongqing Twin City Economic Circle as the research object,To optimize ecosystem services and ecological network layout,The following work has been carried out:First,Starting from the land use/land cover change,Using the equivalent factor method to calculate the ecosystem service value in2005,2010,2015 and 2020,explore the spatial and temporal evolution of ecosystem service value,topographic gradient and response to land use change;Secondly,the geographic detector,Spearman rank correlation coefficient and ecosystem service trade-off synergy(ESTD)are introduced to explore the correlation relations between different types of services and describe their spatial and temporal patterns;Last,Combining the theory of ecosystem service supply and demand and the construction method of landscape ecological security pattern,Establish and optimize the ecological network space layout of Chengdu-Chongqing Twin City Economic Circle,and put forward targeted ecological protection countermeasures according to different ecological function requirements.The main conclusions include:(1)From 2005 to 2020,the ecosystem service value of the study area showed an"N"-shaped fluctuation growth,and the change of ecosystem service value showed significant spatial differentiation.The total value of ecosystem services increased significantly in the non-urban construction concentrated areas between Chengdu and Ya’an,except for food production and waste treatment services,the other 7 types of secondary ecosystem service spatial agglomeration hot spot area showed a U-shaped distribution,it is basically consistent with the clustering characteristics of ecosystem service value hot spot area.The value of ecosystem services generally increases with the increase of the gradient level of each topographic factor.During 2005-2015,land use change had a strong ability to interfere with ecosystem services,while during2015-2020,this ability decreased significantly.The degree of ecosystem service value change caused by land use change was significantly different with different land classes.(2)The influence of the nine types of secondary ecosystem services in the study area showed a higher level on the whole,and the influence of different services on other types of ecosystem services was greater after pin-two interaction.The synergy between different ecosystem services is dominant,In the past 15 years,the correlation coefficient among the ecosystem services in the study area fluctuated within 0.1,with little inter-annual change,and the trade-off/synergy among the services was relatively stable.Spatially,the nine groups of typical ecosystem services were dominated by cooperative units.Only the food production-gas regulation ecosystem service trade-off units accounted for more than 15%,and the overall spatial distribution of trade-off units was scattered.(3)Based on the minimum cumulative resistance model,ecological sources,ecological corridors and ecological nodes were extracted,and ecological functional demand zones were divided to form the ecological network pattern of Chengdu-Chongqing Twin City Economic Circle.Twenty ecosystem service source patches with an area of 39435.48km~2were identified and selected,which were concentrated in hills and mountains in the eastern and western parts of the study area.92 potential ecological corridors and 21 important ecological corridors with a total length of 1284.67km were extracted.Important ecological corridors were mainly distributed in the northeast of the study area and Luzhou and Yibin in the south.Three types of ecological function demand zones,namely ecological buffer zone,ecological sensitive zone and production and living area,accounted for 38.15%,28.70%and11.55%of the total area,respectively.A total of 63 ecological nodes were extracted.(4)Based on the actual situation of the research area,ecological source points,ecological nodes,potential ecological corridors,important ecological corridors,and ecological functional demand zones are optimized and reorganized to form an optimal layout of the ecological network space of"multi-point,five-axis and seven-zone"in the research area,proposed a reasonable layout of ecological nodes,strengthen the construction of"two horizontal and three vertical"ecological corridor and strengthen the construction of zoning management and other targeted ecological protection strategies.The optimized ecological network can effectively guarantee the spatial circulation of ecosystem services and promote the operation of ecological flows,which is crucial for enhancing the value of the overall ecosystem services in the region and exerting important ecosystem functions. |
PDF Full Text Request