森林景观斑块耦合网络节点数与网络结构稳定性之间的关系

Relationship between number of vertices in forest landscape patch coupling network and stability of network structure

以森林景观斑块耦合体为研究对象,利用复杂网络将之抽象化为森林景观斑块耦合网络。选择节点数不同的10个网络,依次对网络进行攻击,利用最大子网节点数与移除比例做回归分析,得每个网络的崩溃阈值。利用网络节点数与网络的崩溃阈值构建与节点数相关的森林景观斑块耦合网络结构稳定性模型,并对模型进行分析。结果表明:从巨型网络-1到微型网络-2的崩溃阈值依次为0.325 9,0.310 1,0.283 4,0.273 0,0.2484,0.215 9,0.194 5,0.196 2,0.158 3,0.157 4,呈递减趋势,说明森林景观斑块耦合体中斑块数越多,其结构越稳定,并通过模型验证这一结论;随着网络节点数的增加,其崩溃阈值增加的速率逐渐减小的,说明当斑块数增加到一定程度时,耦合体的结构稳定性不再变化。根据复杂网络结构特征,用网络的节点数来衡量网络的结构稳定性,进而从新的角度探究森林景观结构的稳定性。

Taking forest landscape patch coupling systems as the research objects, which were abstracted into forest landscape patch coupling networks. Choose 10 networks with different number of vertices, ordinal attacked on networks, when used the largest subnet number of vertices and removed ratio to do regression analysis, each network breakdown threshold would get. Using the number of vertices in the network and the network breakdown threshold build related to the number of vertices of forest landscape plaque stability coupling network structure model, and analyze the model. Results showed that： From the giant network-1 to tiny network-2, values of breakdown threshold were 0.325 9, 0.310 1, 0.283 4, 0.273 0, 0.248 4, 0.215 9, 0.194 5, 0.196 2, 0.158 3 and 0.157 4, showed a trend of decline, the more plaques in the forest landscape patches coupling, the more stable its structure was, and this conclusion was validated by model; With increased of the number of network vertices, increased rate of the breakdown threshold value was decreased gradually, when plaque numbers increased to a certain extent, the structure stability of the coupling system no longer changed. According to the characters of complex network structure, number of vertices in the network was used to measure the structural stability of the network, and then from a new perspective to explore the forest landscape structure stability.