基于CA模型的珠江三角洲基塘景观破碎化分析及其模拟

在对珠江三角洲传统基塘区2000、2006、2011年基塘景观破碎化特征分析的基础上,运用LogisticCA模型开展了传统基塘区2020年的基塘景观的模拟研究。结果表明,2000~2011年,传统基塘区基塘面积减少了46.65%,斑块数量由139个增加到1 072个,平均斑块面积减少了97.12%,反映了斑块由集中成片发展成为破碎的状态;形状指数增加了36.23%,在人类活动的干预下,基塘斑块形状趋于复杂化;边缘密度减少了88.57%,反映了单位面积上斑块数量增多了;平均最近邻近距离变化幅度最大,减少了99.75%,说明相同类型的斑块之间的距离变近,呈团聚分布。根据2020年模拟结果 ,基塘面积减少53.38%,基塘斑块数量增加为2 045个,平均斑块面积减少82.33%,形状指数增加22.12%,边缘密度增加80.74%,平均最近邻近距离减少86.00%,基塘破碎化的程度有所减缓。研究结果可为传统基塘区生态服务功能的延续、农业生态系统的恢复和区域生态经济的可持续发展提供参考。

Analyses and Simulation on Landscape Fragmentation of Dike-pond Based on CA Model in Pearl River Delta

On the basis of analyses on landscape fragmentation of the traditional dike-pond in Pearl River Delta in 2000, 2006 and 2011,the simulation study on traditional dike-pond in 2020 was carried out by Logistic-CA model. The results showed that, during 2000 to 2011, the dike-pond area decreased by 46.65℅, the number of patches increased from 139 to 1 072,the average patch area decreased by 97.12℅, it reflects the plaques become fragmentation from reunion state;Shape in-dex increased by 36.23℅,under the intervention of human activities, dike-pond patch shape tends to complication;Edge den-sity decreased by 88.57℅,it reflects the plaque number on unit area increased;Mean nearest neighbor distance changes sharpest decrease of 99.75℅,it shows that distance between the same type of plaque becomes closer with reunited distribution. According to the simulation results in 2020,the dike-pond area decreased by 53.38℅,the number of patches increased to 2 045, the average patch area decreased by 82.33℅, shape index increased by 22.12℅,edge density increased by 80.74℅, mean nearest neighbor distance decreased by 86.00℅, dike-pond fragmentation degree has slowed. The research results can provide references for continuation of the traditional pond area ecosystem service functions,the recovery of agricultural ecosystem and the sustainable development of regional ecological economy.