景观结构动态变化及其土地利用生态安全——以建三江垦区为例

景观结构动态变化及其土地利用生态安全是区域生态安全和可持续利用研究的重要组成部分。以建三江垦区为研究区,利用遥感手段提取研究区1992年、2000年和2008年的景观类型信息,定量分析了研究区不同尺度的景观结构变化特征。阐明了景观结构变化下的研究区土地利用生态安全形成机制。定量计算研究区不同尺度的景观稳定性,并结合DPSIR模型构建研究区土地利用生态安全综合评价指标体系,对研究区的土地利用生态安全等级进行评价和分析。结果表明:1992-2008年,研究区景观结构变化剧烈,景观基质类型由沼泽湿地转为水田,斑块形状复杂度和景观破碎度增加,斑块空间分布表现为"聚合-分散-聚合"的变化特征;土地利用行为对研究区景观结构产生破坏的同时也对其恢复起调控作用,进而形成景观结构变化下的土地利用生态安全的不同状态,研究区景观结构稳定性可以反映其土地利用生态安全水平;研究期内研究区景观整体稳定性呈"稳定-非稳定-稳定"的复合稳定性特征,土地利用生态安全呈"较安全-临界安全-较安全"的等级变化特征;1992-2000年,旱田景观结构最稳定,2000-2008年,景观结构最稳定类型转变为建设用地,表明该类型土地利用生态安全水平最高,2008年,沼泽湿地是最不稳定的景观类型,土地利用生态安全水平最低。

Research on dynamic changes of landscape structure and land use eco-security:a case study of Jiansanjiang land reclamation area

Research on dynamic changes of landscape structure and land use eco-security is an important part of regional eco-security and sustainable use. This paper selected Jiansanjiang land reclamation area as the study area, got the landscape types of 1992, 2000 and 2008 by Remote Sensing (RS), quantitatively analyzed characteristics of changes of landscape structure of different scales of the study area and elucidated the formation mechanism of land use eco-security based on the variations of landscape structure. The paper quantitatively calculated the landscape structure stability of different scales, and established the comprehensive evaluation indicator system on eco-security of land use based on the DPSIR model to evaluate and analyze the eco-security level of land use in the study area.The results showed that: from 1992 to 2008 the landscape structure of the study area changed dramatically, the landscape matrix type of the study area turned from wetlands to rice paddies, the complexity of patch shape and landscape fragmentation was increased and patch distribution expressed as "aggregation-scattered-aggregation"; Land-use practices not only damaged the landscape structure of the study area, but also made predominant control impact on the recovery, thus the different states of the land use eco-security were formed based on the changes of the landscape structure. The landscape stability of the study area could reflect the status of land use eco-security; the overall landscape stability of the study area demonstrated the "stable-unstable-stable" complex stability and the status of land use eco-security demonstrated the "near safety-critical safety-near safety" dynamic characteristics; from 1992 to 2000, the landscape structure of dry land was the steadiest. From 2000 to 2008, the steadiest type of transformation turned from dry land to construction land, indicating that construction land was at the highest level of land use ecological security. In 2008, the wetland was the most unstable landscape, and it was also at the lowest level of land use ecological security.