乌伦古河流域中下游蒙新河狸生境破碎化评价

Habitat Fragmentation Assessment of Castor fiber birulai in the Middle and Lower Reaches of Ulungur River

在对新疆乌伦古河流域中下游栖息的蒙新河狸Castor fiber birulai生境实地调查的基础上,利用景观格局指数、景观连接度和MaxEnt模型研究其生境破碎化现状,为该物种及其生境的保护和管理提供参考。结果表明:2000—2020年研究区域景观格局变化主要表现为耕地、建设用地和裸地的斑块面积增加,草地、林地和湿地的减少;蒙新河狸适宜生境面积分布狭窄,仅占总面积的12%(386.92 km^(2));适宜蒙新河狸分布的主要环境变量组成特征为最冷月份最低温度(-26.43~-23.07℃)、最暖季度平均温度(20.31~21.78℃)、最干季度降水量(20.04~25.72 mm)、土壤酸碱度(7.72~8.01)、土壤有机碳含量(1.2%~2.6%),以及有草地、林地和水体分布的土地利用类型;不同扩散距离下蒙新河狸适宜生境的景观连接度普遍较低。建议在乌伦古河流域中下游建立蒙新河狸生境廊道,增加斑块间的连通性,改善蒙新河狸的生境。

Based on the field survey conducted on the habitat of Castor fiber birulai in the middle and lower reaches of the Ulungur River basin in Xinjiang,this study utilized landscape pattern indices,landscape connectivity,and the MaxEnt model to examine the current status of habitat fragmentation.This research aims to provide references for the conservation and management of this species and its habitat.The results indicate there are significant changes in the landscape pattern of the studied area from 2000-2020,primarily characterized by the increased areas of cultivated land,built-up areas,and bare land patches,and decreased areas of grassland,forest,and wetland patch.The suitable habitat area for C.f.birulai is narrowly distributed,accounting for only 12%(386.92 km^(2))of the total area.The primary environmental variables influ-encing the distribution of the suitable habitat for C.f.birulai are the minimum temperature of the coldest month(-26.43-23.07°C),the mean temperature of the warmest season(20.31-21.78°C),the precipitation of the driest season(20.04-25.72 mm),the soil pH(7.72-8.01),the soil organic carbon content(1.2%-2.6%),and land use types with distribu-tions of grassland,forest,and water bodies.The landscape connectivity of suitable habitat for C.f.birulai at different dis-persal distances is generally low.It is recommended to establish habitat corridors,increase the connectivity between patches,and improve the habitat for C.f.birulai in the middle and lower reaches of the Ulungur River basin.