Gao Xiang, Liang Yiyin, Zhu Yutian, Zhang Ke, Ding Li, Zhang Peng, Zhu Jianqiao
School of Science, Anhui Agricultural University, Hefei, 230036, Anhui, China.
Key Laboratory of Agricultural Sensors, Ministry of Agriculture and Rural Affairs of China, Hefei, 230036, Anhui, China.
Environ Sci Pollut Res Int. 2023 Apr;30(20):58466-58479. doi: 10.1007/s11356-023-26504-5. Epub 2023 Mar 29.
The wetlands in the middle and lower reaches of the Yangtze River are the main overwintering and perching places for cranes. To examine the habitat selection mechanism of cranes in this area, two natural wetland reserves, Shengjin Lake and Poyang Lake, which are the main habitats of typical cranes, were selected as the study area. Using 20 years of Landsat satellite image data (between 1999 and 2019), the vegetation cover index was calculated from a pixel dichotomy model, and the landscape pattern index was obtained through Fragstats. The entropy method was adopted to determine the weight of the landscape index, and then, the habitat suitability index was calculated. Combined with the number of typical crane populations in the reserve, the selection mechanism of overwintering habitat of cranes was revealed. On the change of land-use type, the crane habitat of Shengjin Lake transferred more to non-crane habitat, and other land types increased, resulting in the decrease of crane habitat area. However, the change of crane habitat in Poyang Lake Reserve was small, so it can accommodate more cranes to overwintering here. In terms of vegetation coverage, most of the vegetation cover areas of Shengjin Lake were woodland near or far from the lake, but the woodland was not the habitat of cranes. Most of the vegetation-covered areas of Poyang Lake are grassland near the lake, which provide rest and foraging places for cranes. In the landscape pattern, the number of landscape patches in Shengjin Lake was large, the degree of landscape fragmentation was higher than that in Poyang Lake, the landscape complexity was higher, and the landscape diversity was simpler. This is not conducive to the maintenance of crane habitat, but also reduces the attractiveness of overwintering cranes, while the landscape suitability of crane habitat in Poyang Lake was higher than that in Shengjin Lake, and cranes were more likely to choose Poyang Lake as their overwintering habitat.
长江中下游湿地是鹤类主要的越冬和栖息场所。为探究该区域鹤类的栖息地选择机制，选取了典型鹤类主要栖息地的两个自然湿地保护区，升金湖和鄱阳湖，作为研究区域。利用20年（1999年至2019年）的陆地卫星影像数据，通过像元二分模型计算植被覆盖指数，并借助Fragstats获取景观格局指数。采用熵权法确定景观指数权重，进而计算栖息地适宜性指数。结合保护区内典型鹤类种群数量，揭示鹤类越冬栖息地的选择机制。在土地利用类型变化方面，升金湖的鹤类栖息地向非鹤类栖息地转移较多，其他土地类型增加，导致鹤类栖息地面积减少。然而，鄱阳湖保护区鹤类栖息地变化较小，因此能够容纳更多鹤类在此越冬。在植被覆盖方面，升金湖大部分植被覆盖区域是湖岸远近的林地，但林地并非鹤类栖息地。鄱阳湖大部分植被覆盖区域是湖岸附近的草地，为鹤类提供了休息和觅食场所。在景观格局上，升金湖景观斑块数量多，景观破碎化程度高于鄱阳湖，景观复杂度较高，景观多样性较单一。这既不利于鹤类栖息地的维持，也降低了对越冬鹤类的吸引力，而鄱阳湖鹤类栖息地的景观适宜性高于升金湖，鹤类更倾向选择鄱阳湖作为其越冬栖息地。
