未来气候情景下青藏高原高寒草原与高寒草甸优势种潜在适宜区分布预测

Distribution of potential suitable areas of dominant species in alpine grasslands and alpine meadows in the TP under future climate scenarios

研究青藏高原高寒草地优势种及草地类型的未来空间分布变化对草地经营管理具有重要意义。基于物种分布数据和主要环境因子,采用最大熵模型(MaxEnt)模拟并分析了高寒草地优势种在当前和未来(2041—2060,2061—2080)不同气候情景(SSP126、SSP245、SSP370、SSP585)下的潜在适宜区及其对气候变化的响应。结果表明:(1)MaxEnt对4类研究物种AUC值均>0.9,预测效果好。(2)早熟禾(Poa annua)类高寒草原主导环境因子是最冷季平均温度(bio11);紫花针茅(Stipa purpurea)类高寒草原、高山嵩草(Carex parvula)类和矮生嵩草(Carex alatauensis)类高寒草甸主导环境因子是年降水量(bio12)。总体而言高寒草地优势种分布受年降水量(bio12)、海拔(Elev)、平均温度日较差(bio2)及降水量季节性变化(bio15)共同驱动。(3)未来气候情景下早熟禾类高寒草原丧失的部分区域会转化为紫花针茅类高寒草原与矮生嵩草类高寒草甸适宜区,高寒草原优势种适宜区质心向西南方向迁移,早熟禾类潜在适宜区在中期(2041—2060)的SSP370情景及远期(2061—2080)的SSP245情景下扩张,其他情景下皆丧失;紫花针茅类的潜在适宜区皆扩张且在SSP370情景下扩张面积达到最大;高寒草甸优势种的潜在适宜区多为扩张趋势且质心向南迁移,仅在SSP585情景下会丧失。本研究不仅可以为保护该地区物种多样性和当地畜牧业生产提供方法参考,也为维持地域生态系统平衡提供理论支持。

It is of great significance for grassland management to investigate the future changes in the spatial distribution patterns of dominant species and grassland types in the Qinghai⁃Tibetan Plateau under the global climate change.Using the maximum entropy model(MaxEnt),this study utilized species distribution data and dominant environmental variables to simulate and analyze potential suitable areas of dominant species in the alpine grassland and alpine meadows in the Qinghai⁃Tibetan Plateau and their responses to climate change under different current and future climate scenarios(SSP126,SSP245,SSP370,SSP585).The results were as follows:(1)The AUC values of MaxEnt for all the four studied species were>0.9,indicating a good prediction effect.(2)The primary driving factors for Poa annua(P.annua)alpine grassland was the mean temperature of the coldest quarter(bio11),while annual precipitation(bio12),Elevation(Elev),mean diurnal range(bio2),and precipitation seasonality(bio15)were important factors affecting the distribution of dominant species in the alpine grasslands and alpine meadows.Stipa purpurea(S.purpurea)alpine grassland,Carex parvula(C.parvula)alpine meadow,and Carex alatauensis(C.alatauensis)alpine meadow included.(3)Under future climate scenarios,some areas lost by P.annua alpine grassland will be transformed into suitable habitats for S.purpurea alpine grassland and C.alatauensis alpine meadow;furthermore,centroids of suitable areas for dominant species in alpine grasslands will shift southwestward.The potential suitable area of P.annua will expand under SSP370 scenario in mid⁃term period(2041—2060)and under SSP245 scenario long term period(2061—2080),but will decrease under other scenarios.The potential suitable area of S.purpurea will expand most significantly under the SSP370 scenario.The potential suitable areas of the dominant species in the alpine meadow tended to expand,and the center of mass migrated to the south,but will be lost only under the SSP585 scenario.This present study provided not only methodological reference for protecting species diversity and local animal husbandry production in this area,but also provided theoretical support for maintaining regional ecosystem balance.