黄河流域鸟类多样性现状、分布格局及保护空缺

The status,distribution patterns,and conservation gap for bird diversity in the Yellow River basin,China

黄河流域幅员辽阔,多样的地理气候、植被类型及人类活动塑造了多样化的生物多样性格局。本研究以IUCN与国际鸟盟发布的鸟类分布图层为基础,同时收集了黄河流域2009–2019年的鸟类实地观测记录,包括观鸟记录、GBIF数据库、红外相机监测及其他实地调查的鸟类数据,共得到35,026条鸟类实地观测有效记录。汇总结果显示,黄河流域记录有鸟类物种662种,占中国鸟类物种总数的45.81%。这些鸟类分属于23目83科,其中雀形目物种数最多(384种,占本目全国鸟种总数的46.83%),其次为鸻形目(67种,占50.00%)和雁形目(39种,占72.22%)。黄河流域受威胁鸟类共计121种,其中有37种和52种分别在IUCN红色名录和《中国脊椎动物红色名录》中被列为受威胁物种(即评估级别为极危、濒危或易危),22种和73种被分别列为国家Ⅰ级和Ⅱ级重点保护野生动物。这些受威胁鸟种多为地栖性、体型大、营养级高或具有长距离迁徙习性的物种。黄河流域鸟类整体物种多样性由南向北递减,以黄河上中游四川、甘肃、陕西的高原与山地内鸟种最为丰富,而受威胁鸟类物种多样性热点区则在黄河中下游,下游黄河三角洲及邻近平原区为受威胁鸟类最主要集中分布区。黄河流域内48个国家级自然保护区共覆盖鸟种数504种(占黄河流域鸟类总种数的76.13%),其中受威胁鸟种92种(占黄河流域受威胁鸟种数的76.03%)。区域内国家级自然保护区大多分布在黄河上游,对黄河下游的受威胁物种覆盖程度较低,保护空缺较严重。对此,我们建议着重加强中下游自然保护区建设与能力提升,增加对中下游受威胁鸟种的保护力度,在保护策略上应当积极探索高强度土地利用下的多样化保护机制。

The Yellow River basin has diverse geographical conditions,climatic conditions,vegetation types,and human activities,all of which shapes the biodiversity patterns for different taxa across this region.Here,we collected bird occurrence data in the Yellow River basin during 2009–2019.We combined data from the range layers published by the IUCN and BirdLife International with 35,026 field observation records(i.e.,birdwatching records from the China Bird Report,eBird,and GBIF,camera-trapping records and other field records).We identified 662 bird species(accounting for 45.81%of the total number of bird species in China)occurring in the Yellow River basin,belonging to 23 orders and 83 families.Passeriformes has the highest number of species(384,accounting for 46.83%of the species of this order in China),followed by Charadriiformes(67 species,50.00%)and Anseriformes(39 species,72.22%).We identified 121 species that are considered threatened.From these species,37 are listed by the IUCN Red List and 52 species are listed by the Red List of China’s Vertebrates as threatened(i.e.,CR,EN or VU),and 22 species are listed as Class-I and 73 species as Class-II national key protected species in China.Birds listed as threatened were typically characterized by having a terrestrial lifestyle,large body size,high trophic level,and migrated long distances.Total species richness was observed on a gradient decreasing from south to north.The southern upriver areas of plateaus and mountains in Sichuan,Gansu,and Shaanxi had the highest species richness.However,threatened bird richness showed a different spatial pattern with hotspots primarily located in the middle and lower reaches of Yellow River,especially on the lowlands near the delta.We identified 48 national nature reserves in the Yellow River basin,covering a total of 504 bird species(76.13%of the region),among which 92 were threatened(76.03%).These national nature reserves were mostly located in the upper reaches of the Yellow River.The coverage of threatened species in the lower reaches was low,which indicates a major gap on protected area coverage.We propose the need to strengthen the construction of protected areas in the middle and lower reaches,specifically for the protection of threatened birds.To conserve the rich bird diversity under high-intensity land use in the Yellow River basin,an integrative framework with diversified conservation strategies is critically needed.