An Integrated Approach to Constructing Ecological Security Pattern in an Urbanization and Agricultural Intensification Area in Northeast China

Ecological security pattern (ESP) can bridge the paradox between ecological conservation and socioeconomic development. Although various methods have been applied to establish ESP successfully, improving its scientificity and reliability for regional sustainability are still great challenges. Taking Harbin administrative region as the study area, this paper integrated the merits of the function-oriented method (assessing the importance of ecological services using the InVEST model) and the structure-oriented method (extracting the connectivity of landscapes based on the MSPA model) to improve the identification of ecological sources more scientifically. Night light data were used to modify the natural resistance surface to reveal the real natural and human disturbance for ES loss during species migration and ecological flows. Then, the ESP was established by combining the ecological nodes after extracting and grading the ecological corridors. The results showed that the individual ES performed with a high spatial heterogeneity and was highly correlated with land use patterns. The extremely important and slightly important were the dominant level types in the study area, and the proportion of extremely important declined greatly from 44.78% in 1980 to 30.14% in 2020. Core was the main landscape type with a proportion of 57.13% and mainly distributed in the Lesser Khingan Mountains and Zhangguangcai Mountains. More than 700 ecological corridors were extracted according to the MCR model and the important ecological corridors were selected based on the gravity model, with 86 ecological nodes obtained from the intersection points of ecological corridors. An ESP of "two zones, two barriers, one axis and one belt" was proposed, and relevant protection measures were put out for the sustainable development in the study area. The findings indicated that imposing ESP could form a stable secure frame for social economic development and ecological protection, avoiding irrational land use modes and excessive dispersion of landscapes. This study could provide valuable references for land use planning and the formulation of related ecological protection policies and regional sustainable development strategies.