基于形态空间格局分析方法和最小累积阻力模型的北京市平原区造林工程生态格局分析

为了科学评估北京市平原区造林工程的生态影响,利用高分卫星数据获取2018—2020年北京市平原区造林面积、分布及变化信息,分析了造林工程的空间格局特征,并采用形态空间格局分析(MSPA)方法及最小累积阻力(MCR)模型,构建了北京市平原区生态网络,通过情景模拟分析造林工程对生态源地、生态廊道产生的影响。结果显示,2018—2020年北京市平原区造林工程主要沿西北东南方向实施,实现了对原有林地资源分布不均衡问题的解决。热点建设区域为北部的延庆及东南部的通州、大兴,呈现由城市边界逐步向市中心蔓延的发展趋势。在不考虑其他因素对土地利用的影响的前提下,造林工程的实施使平原区林地面积增长了9.8%。通过情景模拟发现,造林工程的实施使生态网络向连通、完整、均衡方向发展。其中,生态源地面积增长了131.0 km²,主要生态源地连通性提升了41.1%,生态廊道的分布由主要分布在西北部山区向西北、东南两个方向均有密集分布转变。综上,造林工程的生态环境效应显著,造林工程的实施对生态环境质量改善具有重要意义。

Ecological Pattern Analysis of Afforestation Project in Beijing Plain Areas Using Morphological Spatial Pattern Analysis and Minimum Cumulative Resistance Model

As a megacity,Beijing carries the dual functions of city and capital.The high concentration of functions promoted the rapid urbanization process.In the process of rapid development,a high-density and high-intensity agglomeration pattern with the central urban area as the core has been formed.The ecological space has been gradually occupied by production and living space,resulting in the imbalance of living demand and ecological environment and the fragile ecosystem in the plain area of Beijing.In order to solve the problem of insufficient forest land resources and uneven distribution in the plain area of Beijing,the Beijing municipal government has continuously launched two rounds of plain afforestation projects since 2012.It is hoped that afforestation and afforestation can optimize the ecological pattern and improve the quality of the ecological environment,so as to solve the ecological problems caused by the rapid development of the city.This paper aims to evaluate the optimization effect of the second round of plain afforestation project on the ecological pattern and network of Beijing plain.High-resolution satellite data were used to obtain information on afforestation area,distribution and change in Beijing plain from 2018 to 2020,and the spatial pattern characteristics of afforestation projects were analyzed.The morphological spatial pattern analysis method (MSPA) and minimum cumulative resistance model (MCR) were used to construct the ecological network in the plain area of Beijing,and the impact of afforestation project on ecological source and ecological corridor was analyzed by scenario simulation.The results showed that the afforestation project in the plain area of Beijing from 2018 to 2020 was mainly implemented in the direction of "northwest to southeast",which had effectively solved the problem of uneven distribution of original forest land resources.The key construction areas were Yanqing district in the north and Tongzhou and Daxing districts in the southeast,showing a development trend of gradually spreading from the urban boundary to the city center.Without considering the influence of other factors on land use,the implementation of afforestation project increased the forest land in the plain area by 9.8%.Through the scenario simulation,it was found that the implementation of the afforestation project made the ecological network develop in the direction of connectivity,integrity and balance.The area of ecological sources increased by 131.0 km²,the connectivity of main ecological sources increased by 41.1%.The ecological corridors were mainly distributed in the northwestern mountainous area and densely distributed in the northwest and southeast directions.The afforestation project has a great significance to the improvement of ecological environment.