Temporal And Spatial Changes Of Black-Necked Crane Habitat On The Qinghai-Tibet Plateau

Biodiversity is the basis for the survival and development of human society,and biodiversity conservation is of great significance to sustainable development and national ecological security.The Black-necked Crane(Grus nigricollis)is the only crane species in the world that grows,breeds and winters on the plateau,and is a national Class I protected animal and an indicator species for alpine wetlands.The ecological environment of the Qinghai-Tibet Plateau is extremely sensitive to global climate change and human activities.In order to better protect the Black-necked Crane and its habitat,it is necessary to pay attention to the change of its habitat and carry out long-term habitat suitability evaluation to determine the key areas and gaps of Blacknecked Crane protection.Based on the multi-model combination method,this paper evaluates the habitat suitability of Black-necked Cranes on the Qinghai-Tibet Plateau from 1980 to 2020,and uses the spatial analysis method to overlay its suitable habitats and nature reserves to analyze its protection gaps.The main research methods and conclusions are as follows:(1)In order to determine the long term habitat evaluation index system for Blacknecked Cranes,this study systematically collected its current distribution and environmental factor information in the Qinghai-Tibet Plateau from 2015 to 2020,and used the optimized maximum entropy model(Max Ent)to conduct a preliminary habitat suitability assessment for Black-necked Cranes.The results showed that the optimized Max Ent model reduced the model overfitting,and the habitat selection of Black-necked Cranes on the Tibetan Plateau was mainly influenced by the distance from the water source,altitude and mean annual temperature,preferring to be in the center of shallow lakes or open-water marshes less than 370 m away from the water source,and tending to be distributed in areas with altitudes of 2047-5078 m and mean annual temperatures of-6.76-23.02°C.(2)In the long-term habitat suitability evaluation of Black-necked Cranes from1980 to 2020,based on the results of the Max Ent model,the temporal and spatial characteristics of the habitat suitability of Black-necked Cranes in different periods were analyzed,and the habitat suitability index(HSI)model was used to superimpose various environmental factors evaluation indicators and weights.The results indicate that the Black-necked Cranes are mainly distributed in the northeast of the Qinghai-Tibet Plateau during 1980-2020,specifically in the Zoige wetlands in northern Sichuan,near Qinghai Lake,and in central Tibet and southern Tibet.The area of suitable habitat for Black-necked Cranes declined between 1990 and2000,but increased in the following 20 years.In 2020,compared with 1980,the most suitable habitat expanded mainly in the Naqu city,Zhaqu River and Jinsha River basin in central Tibet,as well as around the Zoige wetland and Qinghai Lake.In addition,the center-of-mass coordinates of Black-necked Crane habitats show a trend of migration to the southern low latitudes and the hinterland of the Tibetan Plateau.(3)In the planning of priority areas for Black-necked Crane conservation and analysis of vacancies in nature reserves,the ZONATION spatial planning model was used to plan priority areas for Black-necked Crane conservation and analyze conservation gaps.The results show that the conservation priority of Black-necked Cranes on the Qinghai-Tibet Plateau is generally higher in the east than in the central and western regions,and the highest conservation priority areas are mainly concentrated in the eastern part of the plateau,central Tibet,the Yarlung Tsangpo River basin,the Hengduan Mountains and the Qilian Mountains.The established nature reserves protect most of the first-level conservation priority areas that are concentrated in space.The protection gaps are mainly located in the northern part of Zoige Wetland and counties around Qinghai Lake,and a small number of protection gaps are located in the Yarlung Tsangpo River Basin,Nima County,and Qinghai Province.Maduo County and Dulan County,Shiqu County in Sichuan Province,and Shangri-La City in Yunnan Province.(4)Based on the above research results,this study suggests focusing on changes in natural factors,because to protect wild animals,we first need to protect their habitats.As an indicator species in the wetland ecosystem,the distribution and quantity of the Black-necked Crane can reflect the ecological environment quality of the wetland to a certain extent.In order to meet the basic foraging,nesting and nocturnal needs of Blacknecked Cranes,it is necessary to strengthen wetland and grassland protection and restoration,delineate important wetland protection areas,reinforce grassland restoration,such as during the breeding season of Black-necked Cranes in April and May,appropriately reduce the grazing time of grasslands in pastoral areas,reduce the impact of human activities on nesting behavior,and provide better breeding habitats for Black-necked Cranes.In order to balance the relationship between the protection of Black-necked Cranes and the development of human economy,adequate economic compensation.