基于生态安全格局的东北典型黑土区生态保护红线划定与优化

Research on the delineation and optimization of ecological protection redline based on the perspective of ecological security pattern in typical black soil areas of Northeast China

东北典型黑土区面临生态系统服务功能退化、景观格局破碎以及农业与生态空间冲突等问题,科学制定具有指导性的黑土区生态保护红线划定与优化框架,对于保障粮食安全与生态安全具有重要意义。基于生态安全格局视角明晰生态保护红线内涵,在考虑生态保护重要性、农业与生态空间协调、自然与社会系统协调的基础上,提出“点—线—面”多层次空间要素的系统性生态保护红线划定思路,考虑生态系统完整性与连通性识别生态保护红线优化区域。结果表明:(1)在保障不划入优质耕地的前提下(阈值为10%),叠加生态系统服务极重要区、生态环境极敏感区、生态系统服务供需不匹配区域确定生态保护红线初步划定区域69646.00 km^(2),并提取生态源地34760.16 km^(2);(2)基于生态源地与构建的综合生态阻力面识别生态廊道10980.90 km与生态节点77个,其缓冲区与生态保护红线初步划定区域共同构成生态保护红线区域76234.54 km^(2);(3)基于破碎度(0.20)和连通度(80)优化阈值,25.48%的生态保护红线区域亟需优化。研究结果提高了生态保护红线划定与优化的科学性和系统性,为东北典型黑土区国土空间精准管控与生态系统可续性管理提供重要依据,且对土地高度集约化利用、生态空间稀缺的中小尺度区域具有重要指导意义。

The typical black soil areas of Northeast China is facing problems such as degradation of ecosystem service functions,fragmented landscape patterns and conflicts between agriculture and ecological space.The scientific formulation of guiding framework for the delineation and optimization of ecological protection redline in black soil areas is of great significance in ensuring food security and ecological safety.This study clarified the meaning of ecological protection redline based on the perspective of ecological security pattern,and proposed the idea of systemic ecological protection redline delineation based on the importance of ecological protection,coordination of agriculture and ecological space,and coordination of natural and social system,and identified ecological protection redline optimization areas by considering the fragmentation and connectivity of ecosystem.The results show that:(1)On the premise of guaranteeing that no high-quality cropland was allocated(the threshold value was 10%),69646.00 km^(2) of the preliminary delineation area of the ecological protection redline were determined by overlaying extremely important areas for ecosystem services,extremely sensitive areas for ecological environment,and areas with mismatch between supply and demand of ecosystem services,and extracting 34760.16 km^(2) of ecological source land;(2)A total of 10980.90 km^(2) of ecological corridors and 77 ecological nodes were identified based on the ecological source and construction of a comprehensive ecological resistance surface,and their buffer zones and ecological protection areas together constituted an ecological protection redline area of 76234.54 km^(2);(3)Based on the optimization thresholds of fragmentation(0.20)and connectivity(80),approximately 25.48%of the ecological redline area was in urgent need of optimization.The results of the study improve the scientific and systematic nature of ecological protection redline delineation and optimization,and provide an important basis for the precise control of land space and strengthening ecosystem sustainability management in typical black soil areas of Northeast China,as well as important guidance for small and medium-scale regions with highly intensive land use and scarce ecological space.