桥梁连陆对海岛土地利用变化的影响:以朱家尖岛为例

摘要

交通条件严重制约和限制海岛的发展,连陆跨海大桥的建设使得海岛与陆地紧密相连,特别是旅游型海岛经济发展提速,大桥建设对海岛土地利用的影响尚不明确.以朱家尖岛为例,依据跨海大桥建成通车时间节点以及遥感影像的可获得性,选取近26 a的5期遥感影像作为数据源进行人机交互式遥感解译.通过土地利用转移矩阵和土地利用动态度模型,揭示土地利用演变过程,探索跨海大桥建成前后土地利用的变化.结果表明:(1)1990-2015年,陆地总面积增加694 hm2;土地利用类型发生较大变化,建设用地面积增加948 hm2(增加521%),耕地面积减少736 hm2(减少37%).(2)海岛土地利用变化对桥梁连陆的响应具有明显的阶段性:连陆前,土地利用动态度先减小后变大;连陆工程建成后,土地利用动态度变大.(3)连陆桥梁的建设直接改变了海岛与陆地之间物质和能量的流通方式,从而间接影响海岛的土地利用格局.%The traffic conditions of an island often seriously restrict its development.A sea-crossing bridge connecting an island with the mainland makes the transportation more convenient and its relations closer, greatly stimulating rapid development of the economy on the island, especially a turism-based island economy.The construction of such a bridge will no wonder have some influences on land use of the island.But so far little has been reported on this aspect.Zhujiajian Island was cited as a case for analysis.Based on timing and availability of remote sensing images of the Zhujiajian Island, five remote-sensing images taken at different times during the past 26 years were selected as the source of data for interpretation of the man-computer interaction type.Transition matrix and land use dynamic models were used to illustrate processes of the change in land use, before and after construction of the bridge.Results show that:(1) During the years of 1990-2015, the island increased in total land area by 694 hm2 and varied sharply in landscape structure and land use, the area of constriction land increased by 948 hm2(521%), while the area of agriculture land decreased by 736 hm2 (37%);(2) The change in land use occurred gradually in coincidence with the construction of the sea-crossing bridge.Before getting connected with the mainland, the island changed slightly in land use with dynamics declining;and once the bridge was erected, it was subjected to great changes in land use;and (3) The bridge has directly changed the pathway of the material and energy flows between the island and mainland, which in turn affects indirectly land use pattern of the island.