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论文运用BP神经网络与CA耦合模型,遴选出驱动滩涂开发的自然、经济、社会方面的23个空间变量,借助Matlab平台,构建了海滨湿地利用空间格局模拟模型。利用盐城大丰海滨1988、2002和2009年三期遥感影像,及相应年份人口经济数据,根据格局优化模拟思路,先使用湿地功能生态位模型诊断出历史过度开发区域,再训练合理开发转换规则,最后仿真出2016年大丰海滨湿地利用的空间优化格局。模拟中依据目标年覆被数量结构,限定训练样本随机抽取比例,提高了1万个样本的有效信息量;通过对比不同BP隐藏层节点数时的模拟精度,确定“23-13-8”和“23-17-8”分别为两组实验的最优BP结构;使得模拟效率提升,仿真总体精度高于93.6%。研究表明,近些年大丰海滨湿地覆被类型间的演替趋于频繁,自然湿地年开发速度明显加快,开发重心不断东移,呈现出向海“滚动开发”的特征。建议放缓两大保护区核心区周边的无序开发,推进大丰港附近滩涂的有序围垦。
In this paper, we use the coupled model of BP neural network and CA to select 23 natural, economic and social variables that drive the development of tidal flats. With the help of Matlab platform, a simulation model of spatial pattern of coastal wetlands utilization is constructed. Based on the remote sensing images of Dafeng seafront in Yancheng city in 1988, 2002 and 2009 and the population data of the corresponding years, according to the pattern optimization simulation method, the over-exploited area of history was first diagnosed using the wetland functional niche model, Finally, the spatial optimization pattern of Dafeng coastal wetland utilization in 2016 is simulated. Based on the number structure of target year overlay in the simulation, the proportion of training samples is limited randomly and the effective information amount of 10,000 samples is increased. By comparing the simulation accuracy of different BP hidden layer nodes, we can determine the number of “23-13-8 ”And“ 23-17-8 ”are the optimal BP structures of the two groups of experiments respectively. As a result, the simulation efficiency is improved, and the overall simulation accuracy is higher than 93.6%. The research shows that in recent years, the succession of wetland cover types in Dafeng coastal wetlands tends to be frequent, the development speed of natural wetlands is obviously accelerated, and the center of development continues to move eastward, showing the characteristics of “rolling development” to the sea. It is suggested to ease the disorderly development around the core areas of the two major protected areas and promote the orderly reclamation of the beach near Dafeng Port.