“两区”建设背景下坝上生态安全格局构建与优化研究

Establishment and Optimization of Ecological Security Pattern in Bashang Area under the Background of"Two-District"Construction

河北坝上地区作为首都“两区”建设的重点区域,其生态安全格局的构建与优化对当地和京津冀区域可持续发展具有重要意义。以2018年土地利用状况为基础,采用InVEST模型计算坝上地区生境质量指数并提取生态源地,选择最小累积阻力模型,构建最小累积阻力表面,划分不同等级的生态安全区,提取生态廊道,并构建河北坝上地区生态安全格局。研究表明:1)坝上地区生境质量总体偏低,50%以上为低等生境质量区,中高等生境质量区约占46%,呈现出生境质量两极分化,类型和分布不均衡等特点;2)生态源地占坝上总面积的17.50%,其中40%以上分布在围场满族蒙古族自治县;3)生态廊道总长度为640.86km,生态节点53个,高等质量生态安全区占25.92%,低等级质量的生态安全区主要分布在张北县、康保县。坝上地区生态安全质量不是很高、生态系统多样性较低,生态资源在空间上分布不平衡,县区之间生态质量差异明显。未来应进一步提升低等级生态区域生态质量,构建更加稳固的生态安全格局。

Bashang area in Hebei Province is the core area of the"two-district"construction for the capital city Beijing,its establishment and optimization of ecological security pattern is of great significance for sustainable ecological development in local area and region of Beijing,Tianjin and Hebei.Ecological sources were extracted from habitat quality index calculated by InVEST model based on the land use data of 2018.The minimum cumulative resistance model was selected to build the minimum cumulative resistance surface.This paper divided ecological security zones into different levels,extracted ecological corridors,and developed ecological security pattern of Hebei Bashang area.The results showed that(1)The habitat quality in Bashang area was generally low,with over 50%of the area at a low level and 46%at medium and high level,presenting the characteristics of polarization of habitat quality,and imbalance in type and distribution,etc.;(2)The ecological source area accounted for 17.50%of the total area of Bashang,and more than 40%of the ecological source area was distributed in Weichang Manchu and Mongolian Autonomous County;(3)The total length of the ecological corridor was 640.86km,and there were 53 ecological nodes.The ecological security zones of high quality in Bashang area accounted for 25.92%,and the ecological security zones of low quality were mainly distributed in Zhangbei County and Kangbao County.The quality of ecological security in Bashang was not very high,the diversity of ecological system was low,the distribution of ecological resources was not balanced in space,and the difference of ecological quality between counties and districts was obvious.In the future,the ecological quality of low-grade ecological regions should be further improved,and a more stable ecological security pattern should be established.