矿业城市景观生态安全研究——一种双层复杂网络分析方法

以土地利用变化（LUC）和景观生态安全指标（LESI）分别作为上、下层网络，通过确定LUC和LESI单层网络的节点、节点重要度和节点连接强度，以及LUC与LESI上下层网络之间的节点连接系数，形成LUC-LESI双层复杂网络模型，并构建度中心性、聚类相关性和节点影响强度等3个复杂网络指标，定量分析区域土地利用变化与景观生态安全之间的内在有机联系，为土地利用调控提供指导.大冶市案例研究结果表明，2005~2015年大冶市景观生态安全状况相对稳定，7个乡镇景观生态安全状况得到提高，8个乡镇景观生态安全状况降低，景观生态安全总体处于第4等级；耕地减少和建设用地增加在LUC网络中处于核心位置，是整个网络的骨架，香农多样性指数SHDI在LESI网络中处于核心位置，对区域景观生态安全的影响最大，耕地减少和建设用地增加在区域景观生态安全变化中起主导作用；建设用地扩张主要占用耕地，耕地-建设既有相对集中的大面积开发区，又存在工矿建设的遍地开花，且建设主要沿道路线性展开，导致耕地-建设的平均斑块面积大、斑块聚集度较低、斑块形状指数较高；耕地改种树木现象在各乡镇已较为普遍，单块面积较大且相对集中，而耕地抛荒主要发生在山丘区域，虽集中度高但单块面积较小，耕地改种树木和耕地抛荒多表现为成片进行，导致耕地-林地平均斑块面积较大而耕地-草地平均斑块面积小，两者斑块聚集度均较高，斑块形状指数均较低.LUC-LESI双层复杂网络实现了景观生态安全与土地利用变化之间关系的定量化表达，可以作为区域景观生态安全研究的一种有效分析工具.

The landscape ecological security of a mining city: A two-layer complex network analysis method

This study used land use change (LUC) and landscape ecological security indicators (LESI) as the upper and lower networks, by selecting the nodes, node importance and node connection strength of LUC and LESI single-layer networks, as well as the node connection coefficients of LUC and LESI upper and lower layers, formed a LUC-LESI two-layer complex network model, and constructed 3 complex network indicators such as degree centrality, clustering correlation and node influence intensity, quantitatively analyzed the internal organic connection between regional land use changes and landscape ecological security, provided a guidance for the land use regulation. The results of the Daye City case study showed that, from 2005 to 2015, the landscape ecological security status of Daye City was relatively stable, the landscape ecological security status of 7 towns was improved, and the landscape ecological security status of 8 towns was reduced, and the landscape ecological security was generally at the 4th level. The decrease in cultivated land and the increase in construction land were at the core of the LUC network and were the backbone of the entire network; The Shannon diversity index was at the core of the LESI network, which had the greatest impact on the regional landscape ecological security. The decrease of cultivated land and the increase of construction land played a leading role in the change of the regional landscape ecological security. The expansion of construction land mainly occupied cultivated land; The conversion of cultivated land to construction land had relatively concentrated large-area development zones with the industrial and mining construction blooming all over the place; Also, the construction was mainly spread linearly along roads, resulting in a large patch area of the cultivated land converted to construction land, the low degree of patch aggregation, and a higher patch shape index. The phenomenon of replanting trees on the cultivated land had become common in all towns. The area of a single block was relatively large and relatively concentrated. The abandonment of cultivated land mainly occurred in the hilly area. Although the concentration was high, the single block area was small. The conversion of cultivated land to trees and the abandonment of cultivated land were mostly carried out in patches, resulting in an averagely larger patch area of cultivated land converted to forest land, and an averagely smaller patch area of cultivated land converted to grassland. Both of them had a higher patch aggregation and a lower patch shape index. The LUC-LESI two-layer complex network realized the quantitative expression of the relationship between the