高寒草甸区高原鼢鼠新生土丘水土流失特征  

Effect of Soil Erosion of Plateau Zokor New Mound in Alpine Meadow

作　　者：马素洁 周建伟[1] 王福成 牛钰杰 楚彬[1] 周延山[1] 姬程鹏 王婷[1] 花立民[1] MA Sujie;ZHOU Jianwei;WANG Fucheng;NIU Yujie;CHU Bin;ZHOU Yanshan;JI Chengpeng;WANG Ting;HUA Limin(Gansu Agricultural University,Lanzhou 730070;Tibet Agriculture&Animal Husbandry University,Linzhi,Xizang 860000)

机构地区：[1]甘肃农业大学,兰州730070 [2]西藏农牧学院,西藏林芝860000

出　　处：《水土保持学报》2019年第5期58-63,71,共7页Journal of Soil and Water Conservation

基　　金：国家重点研发计划项目(2017YFC0504803,2016YFC0501902);甘肃省高校协同创新科技团队支持计划项目

摘　　要：高原鼢鼠是青藏高原的优势地下啮齿动物,掘洞造丘是其独特的行为之一。高原鼢鼠新生土丘属于次生裸地容易导致水土流失,研究高原鼢鼠新生土丘水土流失对于合理评价其对生态系统的影响具有重要意义。利用径流小区法和风蚀桥法,测定不同地形(平地和坡地)、不同直径大小(大土丘:直径>75 cm,中等土丘:直径50~75 cm,小土丘:直径<50 cm)单位面积新生土丘年土壤流失量和有机质流失量,并比较经过1年侵蚀后的土丘与无土丘草地表层(0—10 cm)土壤粒径组成、含水量和营养成分,旨在明确高原鼢鼠不同大小和不同分布的土丘的水土流失状况。结果表明:(1)研究区平地和坡地新生土丘单位面积年均土壤流失量分别为4 039.91,3 731.79 g/m^2,单位面积年均土壤有机质流失量分别为266.83,252.76 mg/m^2,土壤侵蚀级别为中度侵蚀;(2)土丘表层土壤粒径<0.25 mm和>5 mm的团聚体含量均显著小于无土丘草地(P<0.05),>0.25 mm的团聚体含量显著大于无土丘草地(P<0.05);(3)土丘表层土壤肥力和土壤含水量均显著小于无土丘草地表层土壤(P<0.05);(4)雨季坡地新生土丘单位面积泥沙流失量显著高于平地新生土丘(P<0.05)。风季平地风蚀厚度大于坡地风蚀厚度,分别为4.33,3.62 cm;(5)风季不同丘型土丘的侵蚀厚度表现为大土丘>小土丘>中土丘,分别为5.50,3.59,2.82 cm。研究认为高原鼢鼠新生土丘会导致高寒草甸风蚀和水蚀发生,且不同地形和不同大小的土丘水土流失情况各异。Plateau zokor is the dominant subterranean rodent in Qinghai-Tibet plateau and it burrows soil of the ground surface to form new mounds,which is a kind of bare land that easily causes soil erosion.It is of great significance to study soil erosion of new mounds caused by plateau zokor to evaluate the impact of the zokor on alpine meadow ecosystem.This study used the runoff plot method and the wind erosion bridge method to determine the annual soil erosion and organic matter loss on the new mounds,and compared the soil particle composition,soil moisture and soil nutrients contents between the new mounds and the surface soil(0—10 cm)on the grassland without mounds.The purpose was to clarify the soil erosion of the new mounds on different topography,including plain and slope,as well as different size new mounds,involving large(diameter>75 cm),moderate(diameter 50~75 cm)and small(diameter<50 cm).The results showed that:(1)In plain and slope area,the annual soil loss of plateau zokor mounds was 4 039.91 and 3 731.79 g/m^2 respectively,and the annual soil organic matter loss was 266.83 and 252.76 mg/m^2 respectively.The soil erosion level of plateau zokor mound was moderate;(2)Both the contents of soil aggregates with size of<0.25 mm and>5 mm in mounds surface were significantly less than that of grassland without mounds(P<0.05),and the soil aggregates contents of>0.25 mm in mounds surface was significantly greater than that of grassland without mounds(P<0.05);(3)The soil fertility and soil moisture of mounds’surface soil were significantly less than that of grassland without mounds(P<0.05);(4)The amount of sediment loss of new mounds on the slope was significantly higher than that of the plain in the rain season(P<0.05).The wind erosion of zokors’mounds on the plain was greater than that on the slope in the wind season,the thickness of wind erosion on the plain and slope was 4.33 and 3.62 cm,respectively;(5)The thickness of wind erosion of different size mounds in the wind season was highest on the large mounds,f

关 键 词：高寒草甸 新生土丘 水土流失 

分 类 号：S157.1[农业科学—土壤学]