基于CLUE-S模型的三江平原景观格局变化及模拟

三江平原是我国沼泽地集中连片且分布面积最大的地区之一,在维持区域生态安全方面发挥着不可替代的作用.本研究基于3S技术,对1980-2010年三江平原土地利用和景观格局变化进行分析.结果发现: 1980-2010年,研究区景观格局主要变化特征为沼泽地面积减少7135 km²,减幅达59.1%,水田面积增加18010 km²,增幅达610.1%;景观指数分析结果表明,斑块数量增加,景观破碎化越来越严重,景观异质性增加,各景观类型向均匀化方向发展.基于1980-2010年5期土地利用图对CLUE-S模型进行校正和验证,30年时间尺度上模拟结果与真实景观的Kappa指数为0.71,说明模型适宜研究区30年内的模拟研究.基于校正好的模型对2010-2030年湿地变化进行多预案模拟(历史预案、规划预案、生态恢复预案),结果显示,历史预案下,沼泽地面积减少2515.44 km²,水田面积增加19656.24 km²;规划预案下,沼泽地面积减少303.28 km²,水田面积增加1392.08 km²;生态恢复预案下,沼泽地面积增加3585.60 km²,水田面积增加289.72 km².应用景观指数评价模拟结果为:历史预案下,景观格局破碎化越来越严重;规划预案下,景观格局变化不大;生态恢复预案下,湿地面积不断增加,湿地连通性升高,各景观类型向均衡方向发展,景观格局不断优化.

Landscape pattern change and simulation in the Sanjiang Plain based on the CLUE-S model.

The Sanjiang Plain is one of the most concentrated and contiguous area of marshes, which plays an irreplaceable role in maintaining regional ecological security. Based on the 3S technology, we examined the changes in land use and landscape pattern of the Sanjiang Plain from 1980 to 2010. The results showed that marshland area lost 7135 km², with a loss rate of 59.1%. The paddy area increased 18010 km², with a growth rate of 610.1%. The results of landscape indices analysis showed that the number of patches increased, the landscape fragmentation became stronger, the landscape heterogeneity increased, and the different landscape types became homogenized. The CLUE-S model was validated based on the five different periods of land use maps during 1980-2010. The Kappa index between the simulation and actual measurement at the time scale of 30 years was 0.71, indicating that the model was suitable for 30 years simulation in the study area. The future wetland changes in the Sanjiang Plain from 2010 to 2030 was simulated with validated CLUE-S models, including historical development scenario, planning scenario, and ecological restoration scenario. The simulation results showed that the marsh land would decrease 2515.44 km² and the paddy area would increase 19656.24 km² in the historical development scenario. The marsh land would decrease 303.28 km², but the paddy area would increase 1392.08 km² in the planning scenario. The marsh land would increase 3585.61 km² and the paddy area would increase 289.72 km² in the ecological restoration scenario. The landscape patterns of the three scenarios were estimated using landscape indices. The results showed that the landscape pattern fragmentation would become more and more serious in the historical development scenario. The landscape pattern would have no signifi-cant changes in the planning scenario. The wetland area and connectivity would increase, the different landscape types would become balanced, and the landscape pattern would be gradually optimized in the ecological restoration scenario.