1976-2013年三江平原景观生态风险变化及驱动力

受自然过程和人类活动的影响，三江平原景观生态风险格局发生了明显变化。采用GIS和RS技术构建景观风险指数，结合网格分析法和地理探测器分析1976-2013年三江平原景观生态风险变化及驱动力。结果表明，从时间上看，1976-2013年三江平原农田、草地和湿地的景观损失度逐渐降低，林地和居民用地景观损失度不断升高，生态风险呈逐渐降低趋势；从空间上看，1976年以高风险区为主，2013年则以低风险区为主，1976-2013年低风险、较低风险和中风险区不断向三江平原西部和西南部扩张，高风险和较高风险区逐渐向北部的黑龙江和乌苏里江沿岸及保护区退缩，生态风险整体向西南方向运移，风险质心向西南转移37.8 km；三江平原景观生态风险格局变化受海拔、地貌、居民点、保护区距离和人为干扰度影响明显，其中人为干扰度、居民点以及保护区距离对景观生态风险解释力最为显著，1995年人为干扰度（71.2%）、居民点距离（64.6%）和保护区距离（43.7%）的因子解释力明显高于地貌类型（11.2%）和流域类型（8.9%），2013年地貌类型（23.5%）解释力大于保护区距离（23.3%）。该研究为湿地保护和恢复提供科学参考。

A long-term site study for the ecological risk migration of landscapes and its driving forces in the Sanjiang Plain from 1976 to 2013

The ecological risk pattern of the landscape on the Sanjiang Plain has experienced tremendous change in recent years, with the influence of natural processes and human activities. In this study, we collected data in the Sanjiang Plain from 1976 to 2013. Based on GIS and RS technologies, we established a landscape risk index, and simultaneously analyzed the corresponding driving forces for the ecological risk of landscapes in the Sanjiang Plain, using grid analysis and the geographic detector method. The results showed that landscape loss of farmland, grassland, and wetlands decreased slowly, whereas the loss of forest land and residential land continued to increase. Overall, the ecological risk was lower in the Sanjiang Plain from 1976-2013. From the spatial distribution perspective, the landscape ecosystem was primarily at a high risk in 1976, whereas it was primarily at a low risk in 2013. In addition, the areas with low, low-medium, and medium risks continued to expand into the vast west and southwest regions of the Sanjiang Plain, which was accompanied by a gradual retreat of the medium-high and high risk areas to the north of Heilongjiang and to the eastern Wusuli River along the protected areas and banks. From 1976 to 2013, ecological risk experienced a gradual migration to the southwest of the Sanjiang Plain, and the risk center of gravity migrated a distance of 37.8 km. The landscape pattern of ecological risk in the Sanjiang Plain experienced a change that was influence by altitude, geomorphology, residential distance, distance from the reserve, and human disturbance, whereas residential distance, human disturbance, and distance from the reserve explained much of the landscape ecological risk. The explanatory power of human disturbance (71.2%), residential distance (64.6%), and distance from the reserve (43.7%) was significantly higher than that of geomorphology type (11.2%) and basin type (8.9%) in 1995, and the explanatory power of the geomorphology type (23.5%) in 2013 was also slightly greater than that of distance from the reserve (23.3%). This result could provide a scientific basis for wetland protection and restoration.