基于土地利用的杭州湾滨海湿地景观生态风险评价

Landscape Ecological Risk Assessment of Hangzhou Bay Coastal Wetland Based on Land Use

明确滨海湿地景观生态风险评价对于湿地生态保护和修复具有重要意义.本文基于1995年至2015年5期遥感数据分析杭州湾滨海湿地土地利用动态变化特征,结合景观生态风险评价模型和空间分析方法,分析1995—2015年湿地生态风险时空分异特征和空间相关性.结果表明:1)1995—2015年景观格局变化较大,其中建设用地增量最多,水域面积持续下降,大量沿海水域滩涂被围垦转换为其他用地类型;2)研究区总体生态风险呈好转趋势,但局部地区生态风险仍然居高;较高风险和高风险区面积持续下降,分布呈现不断向海域推进趋势,低风险和较低风险区面积上升,主要分布在研究区南部和中部;3)研究区各时段生态风险空间分布呈正相关,并在空间上聚集.冷点区主要分布在景观类型较为单一、人为干扰小的南部和东南部地区,热点区主要分布在城镇化较快的西南地区和围垦速度较快的沿海区域.热点和冷点的分布与研究区区域地理环境具有较高的耦合性,整体生态风险地域性增强.研究结果可以为杭州湾滨海湿地的开发利用和保护恢复提供参考.

It is important to clarify the ecological risk assessment of coastal wetland landscape for wetland ecological protection and restoration.Based on five periods of remote sensing data from 1995 to 2015,combined with landscape ecological risk assessment model and spatial analysis method,this paper analyzed the dynamic characteristics of land use in Hangzhou Bay coastal wetland,and analyzed the spatial-temporal variation characteristics and spatial correlation of wetland ecological risk from 1995 to 2015.The results showed that:1)From 1995 to 2015,the landscape pattern changed greatly with the largest increment of construction land and the continuous decline of water area,and a large number of coastal water beaches were reclaimed and converted to other land types;2)The overall ecological risk in the study area showed an improving trend,but the local ecological risk was still high.The area of high-risk and less high-risk areas continued to decline,and the distribution trend continued to move towards the sea.On the other hand,the area of low-risk and less lowrisk areas increased,which mainly distributed in the southern and central parts of the study area;3)The spatial distribution of ecological risk in each period of the study area was positively correlated and spatially aggregated.The cold spots were mainly distributed in the south and southeast where the landscape type was relatively simple and the human disturbance was small.The hot spots were mainly distributed in the southwest area where the urbanization was fast and the coastal areas where the reclamation speed was fast.The distribution of hot spots and cold spots had a high coupling with the regional geographical environment in the study area,and the overall ecological risk was enhanced regionally.These research results could provide important scientific management suggestions for the development,utilization,protection and restoration of Hangzhou Bay coastal wetlands.