摘要
黑颈鹤(Grus nigricollis)是青藏高原的特有鹤类,其目前已知最大的越冬栖息地位于我国的西藏自治区。根据以往调查,约6000只黑颈鹤越冬于西藏的雅鲁藏布江中上游河谷以及拉萨河—彭波河谷地区,而仅有少量个体在林芝地区越冬。2016～2017年,对西藏东部雅鲁藏布江下游湿地进行调查时,在位于林芝地区的尼洋河与雅鲁藏布江汇合处的"T"型河谷地带记录到527只黑颈鹤在沙洲及江岸农田中集群越冬,总数约占该物种全球种群的5.0%。两年的连续观察中记录到该越冬种群幼体新增率分别为8.64%和6.64%,这或许意味着该种群在其对应的繁殖地及迁徙停歇地受到威胁。建立MAXENT模型,发现海拔为影响研究区域内黑颈鹤栖息地选择的最主要环境因素,且其潜在栖息地主要位于海拔在2920 m的地区,总面积约为131.98 km^2,因此,若假设不同强度的干扰使得水位以5 m为单位上升,黑颈鹤的潜在越冬栖息地将依次减少至当前栖息地面积的54.42%(2925 m),42.72%(2930 m),31.71%(2935 m),22.33%(2940 m),14.86%(2945 m)以及9.03%(2950 m)。鉴于该越冬栖息地生境狭窄的特殊性,因气候变化或人类活动所引起的水位上升将会对黑颈鹤该越冬种群的生存产生不可逆转的影响。
Black-necked crane(Grus nigricollis)is endemic to the Tibetan Plateau,the site of its largest and most significant wintering habitats.According to current investigations,approximately 6000 black-necked cranes winter in the upper-middle valley of the Yarlung Zangbo River and Lhasa River-Pengbo Valley,while only a few flocks were reported wintering in Nyingchi Prefecture.During 2016-2017 we conducted field survey in the lower reaches of wetlands along the Yarlung Zangbo River.We recorded 527 b Based on our two-year survey,the recruitment rate of this wintering population was 8.64%and 6.64%respectively,probably suggesting that this population is threatened in its breeding or stopover habitats.We used a MAXENT model to determine that elevation(2920 m)was the most significant factor in determining black-necked crane wintering habitat selection,and the area of potential wintering habitats was 131.98 km 2.Consequently,if we assume the disturbances of various magnitudes lead to wetland water levels rising in increments of 5 m,the wintering habitats of black-necked cranes would decrease to 54%(2925 m),43%(2930 m),32%(2935 m),22%(2940 m),15%(2945 m)and 9%(2950 m)of its present habitat area.Considering the narrow distribution of the wintering grounds in this region,rising water levels caused by climate change or other anthropogenic activities would exert irreversible impact on the survival of this wintering population of black-necked crane.
作者
韩雪松
郭玉民
Han Xuesong;Guo Yumin(College of Nature Conservation,Beijing Forestry University,Beijing,100083,China)
出处
《野生动物学报》
北大核心
2018年第3期539-549,共11页
CHINESE JOURNAL OF WILDLIFE
基金
国家林业局及国家自然科学基金(项目编号31770573)资助
关键词
西藏
林芝
黑颈鹤
越冬栖息地
MAXENT
栖息地选择偏好
水位上升
Tibet
Nyingchi
Black-necked crane(Grus nigricollis)
Wintering habitat
MAXENT
Habitat selection preference
Rising water stage
