中国阿勒泰地区鸟类物种编目、丰富度格局和区系组成

Avian species census,richness patterns and faunal composition in the Altay Region,China

中国阿勒泰地区位于新疆北部,与哈萨克斯坦、俄罗斯、蒙古国交界,该区包含阿尔泰山及山前荒漠和绿洲,属于全球200个生物多样性最丰富和最具代表性生态区之一的阿尔泰–萨彦岭生物热点地区。阿勒泰地区生境多样,鸟类物种资源丰富。尽管以往曾在阿勒泰地区进行过一些鸟类调查,但对于该地区不同景观和生境类型中鸟类物种丰富度和分布尚无详尽报道。本文通过2013–2016年在中国境内阿尔泰山及山前平原地区对不同生境类型中的鸟类进行实地调查,并总结文献资料及观鸟爱好者的记录数据,重新整理了阿勒泰地区鸟类名录及地理分布,分析了鸟类的物种组成、区系成分;通过鸟类分布位点数据,选取气候、土地覆被类型、人类足迹指数及地形共4类环境因子作为自变量建立MaxEnt生态位模型,通过模拟77种鸟类的适宜分布区并叠加分布图层,获得了阿勒泰地区的鸟类物种丰富度分布格局。结果表明:阿勒泰共记录鸟类344种,隶属19目55科149属,其中雀形目163种。在垂直海拔带上,鸟类物种数分别为高山裸岩带24种,高山草甸带35种,山地森林草原带172种,低山灌木带130种,荒漠草原带84种,平原绿洲带173种,以及各海拔带的湿地与水域生境中水鸟92种;在区系成分上,以北方型鸟类为主(170种,占49.4%),其次为广布种(93种,占27.0%)。阿尔泰山地的鸟类区系呈现出西伯利亚动物区系特征,山前平原地区呈现蒙新区分布特征,因此,阿勒泰地区动物地理区系属于古北界欧洲–西伯利亚亚界阿尔泰–萨彦岭区阿尔泰亚区;山前平原地区属于古北界中亚亚界蒙新区西部荒漠亚区。Max Ent模型推测阿勒泰地区山前平原绿洲地区、山地森林草原带和低山灌木带具有较高的鸟类物种丰富度,尤其是额尔齐斯河流域下游的绿洲带宽阔,鸟类物种丰富,而高山区和荒漠生境中鸟类物种相对较少。模型预测的结果与实际调查情况相符。阿勒泰地区应采用生态友好的经济发展策略,加强对乔木和灌木的保护,这有助于维持较高的鸟类物种多样性。此外,降低生境破碎化不仅对该地区物种保护有重要作用,也对维持阿尔泰–萨彦岭生物热点地区的山地鸟类多样性有重要意义。

The Altay Region in China is located in North Xinjiang,in the border region of China,Kazakhstan,Russia and Mongolia.The region contains the Altai Mountains and the desert and riparian landscapes south of them,which constitutes the Altai-Sayan biodiversity hotspot and one of the Global 200 Biodiversity Ecoregions.Being composed of diverse habitat types,the Atlay region harbors a rich avian fauna.Though there are several field studies on a few avian species in the Altay Region,few studies have focused on broad-scale species diversity and distribution patterns across different habitats and landscapes.Thus,we completed a comprehensive census across various landscapes and habitats in the region.In this study,we recorded bird species in different types of habitats on the southern slope of the Altai Mountains and the plains area south of the Altay Region from 2013 to 2016.We also collected information from the literature and local citizen science records.The resulting bird species inventory allowed us to use MaxEnt models to predict distributions and diversity patterns of 77 bird species in the Altay Region.Four classes of environmental predictor variables,i.e.climatic factors,land cover type,human footprint index and terrain were incorporated into the models.We predicted all species’distribution patterns and added all species’distribution layers together to determine broad-scale diversity patterns.In total,19 orders,55 families,149 genera and 344 bird species were represented in the Altay Region of China.Along the vertical vegetation belts,there were 24 species in high mountain-bare rock belt;35 in alpine meadows;172 in mountain forest belt;130 in brush land in low mountains;84 in desert belt;173 in riparian belt;and an additional 92 species in wetland and water areas.In the Altay Region,Palearctic type birds dominated the avian fauna with 170 species(49.4%)and followed by widespread northern species(93 species;27.0%).The Altai Mountains belonged to Palearctic Realm,Europe-Siberia Sub-realm,Altai-Sayan Region and Altai Sub-zoogeographical Region,while the plain areas belonged to Palearctic Realm,Central Asia Sub-realm,Inner Mongolia-Xinjiang Region and West Desert Subregion.The MaxEnt models predicted high species diversity in the riparian,plains,and middle and lower montane areas,congruent with previous field data.Protecting tall trees and young saplings and shrubs through eco-friendly economic development strategies and preventing habitat fragmentation will help maintain high species richness in the Altay Region and the Altai-Sayan Ecoregion.