Wang Chenxi, Xia Shaoxia, Yu Xiubo, Wen Li
Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100190, China.
Science and Insights, Department of Climate Change, Energy, the Environment and Water, Parramatta, NSW, 2150, Australia.
J Environ Manage. 2024 Nov;370:122360. doi: 10.1016/j.jenvman.2024.122360. Epub 2024 Sep 7.
The availability of high-quality food resources is a critical determinant of wildlife fitness. Over the past two decades, phenological mismatch - the temporal misalignment between animals' peak nutrient demand and optimal resource availability - has emerged as a significant conservation challenge. This issue is particularly worrisome for migratory birds, which must accumulate energy reserves to meet the elevated metabolic demands of migration between breeding and wintering grounds. In Poyang Lake, a crucial wintering ground along the East Asian-Australasian flyway, increasing asynchrony between vegetation growth and the migration of herbivorous waterbirds significantly impedes conservation efforts and presents a major management challenge for this Ramsar wetland. This study evaluates the efficacy of mowing, a grassland management measure, in regulating plant growth processes and restoring food resources for geese. In-situ mowing experiments were conducted with varying timings in Carex wet meadows, the primary foraging habitats of geese. Optimal mowing times were identified, and the maximum goose carrying capacity was assessed by comparing Carex growth and nutritional dynamics with goose dietary requirements. The results reveal that mowing effectively slows down the aging process of Carex, and protein content is identified as a critical limiting factor for geese foraging. Different mowing timings extend the suitable foraging period by 11-25 days. Estimates suggest varying carrying capacities with different mowing timings, supporting goose populations ranging from 133 to 2,046 in Changhuchi Lake during wintering. The optimal mowing window is early October, avoiding dates before late September and after late November. Moreover, multiple-stage mowing is recommended to accommodate different wintering stages. The study highlights mowing as a potential habitat restoration approach for goose conservation, effectively mitigating the challenges imposed by phenological mismatch directly and indirectly caused by anthropogenic activities.
高质量食物资源的可获得性是野生动物健康状况的关键决定因素。在过去二十年中，物候不匹配——动物的营养需求高峰期与最佳资源可获得性之间的时间错位——已成为一个重大的保护挑战。这个问题对于候鸟来说尤其令人担忧，它们必须积累能量储备以满足在繁殖地和越冬地之间迁徙时增加的代谢需求。在东亚-澳大利西亚候鸟迁徙路线上的重要越冬地鄱阳湖，植被生长与食草水鸟迁徙之间日益增加的不同步性严重阻碍了保护工作，并给这片拉姆萨尔湿地带来了重大管理挑战。本研究评估了割草这一草地管理措施在调节植物生长过程和恢复鹅的食物资源方面的效果。在鹅的主要觅食栖息地苔草湿草甸进行了不同时间的原位割草实验。确定了最佳割草时间，并通过比较苔草生长和营养动态与鹅的饮食需求来评估最大载鹅量。结果表明，割草有效地减缓了苔草的衰老过程，蛋白质含量被确定为鹅觅食的关键限制因素。不同的割草时间将适宜觅食期延长了11至25天。估计不同割草时间的载鹅量不同，在冬季，长湖池湖可支持133至2046只鹅的种群数量。最佳割草窗口是10月初，避免9月下旬之前和11月下旬之后的日期。此外，建议采用多阶段割草以适应不同的越冬阶段。该研究强调割草作为一种潜在的栖息地恢复方法对鹅的保护作用，有效缓解了由人为活动直接和间接导致的物候不匹配所带来的挑战。
