禁牧封育对祁连山南麓高寒草甸植被群落结构及土壤水分特征的影响  

Effects of Grazing Prohibition on Vegetation Community Structure and Soil Moisture Characteristics of Alpine Meadows on the Southern Slope of the Qilian Mountains

作　　者：宋成刚 张铭洋[3] 何琦 王军邦 王文颖[1] 杨永胜 樊博[3,6] 周华坤 SONG Chenggang;ZHANG Mingyang;HE Qi;WANG Junbang;WANG Wenying;YANG Yongsheng;FAN Bo;ZHOU Huakun(College of Geographical Science,Qinghai Normal University,Xining 810008,China;Qinghai Engineering Consulting Center Co.,LTD,Xining 810001,China;Northwest Institute of Plateau Biology,Chinese Academy of Sciences/Key Laboratory of Restoration Ecology of Cold Area in Qinghai Province/Key Laboratory of Adaptation and Evolution of Plateau Biota,Chinese Academy of Sciences,Xining 810001,China;College of Horticulture and Gardening,Yangtze University,Jingzhou 434025,China;Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences/Key Laboratory of Ecosystem Network Observation and Modeling,Chinese Academy of Sciences,Beijing 100101,China;Qinghai Haibei National Field Research Station of Alpine Grassland Ecosystem,Xining 810001,China)

机构地区：[1]青海师范大学地理科学学院,青海西宁810008 [2]青海省工程咨询中心有限公司,青海西宁810001 [3]中国科学院西北高原生物研究所/青海省寒区恢复生态学重点实验室/中国科学院高原生物适应与进化重点实验室,青海西宁810001 [4]长江大学园艺园林学院,湖北荆州434025 [5]中国科学院地理科学与资源研究所/中国科学院生态系统网络观测与模拟重点实验室,北京100101 [6]青海海北高寒草地生态系统国家野外科学观测研究站,青海西宁810001

出　　处：《中国草地学报》2023年第4期22-32,共11页Chinese Journal of Grassland

基　　金：青海省应用基础研究项目(2022-ZJ-716);国家自然科学基金联合项目(U20A2006);国家自然科学基金青年项目(32001149);国家自然科学基金面上项目(31971507);青海省“昆仑英才·高端创新创业人才”计划(2022);中国科学院青年创新促进会(2022436)。

摘　　要：以祁连山南麓高寒草甸为研究对象,设置自然放牧(3.5羊单位/hm2)、封育4 a、封育11 a样地,分析不同禁牧年限下研究区植被群落结构和土壤水分特征的变化规律。结果表明:植被高度、盖度、地上生物量随禁牧年限延长呈先升高后降低趋势,地下生物量及总生物量呈先降低后升高趋势。封育4 a与自然放牧(对照)相比,植被高度、盖度显著升高(P<0.05),地上生物量增加45.95%,地下生物量及总生物量分别降低4.71%、9.00%(P<0.05)。封育11 a时,植被高度、盖度及地上生物量较封育4 a呈下降趋势,地下生物量及总生物量分别增加13.88%、18.50%(P<0.05)。随禁牧封育年限的增加,植被群落物种数无明显变化,群落结构变化明显。与自然放牧(对照)相比,封育11 a样地植物多样性指数显著降低11.01%(P<0.05),均匀度指数降低4.20%,优势度指数增加40.28%。短期禁牧封育(封育4 a)对土壤最大持水量、毛管持水量、饱和导水率的影响主要集中在0~30 cm土层。随着封育年限的增加,0~30 cm土层土壤毛管孔隙度和总孔隙度均呈先增加后降低趋势,非毛管孔隙度无明显变化。综上所述,短期禁牧封育有利于研究区植被群落结构改善及土壤水分特征的恢复,禁牧年限过长不利于退化草地植被群落及水源涵养功能的可持续恢复。The objective of this study was to investigate the effects of grazing prohibition for different durations(natural grazing with 3.5 sheep/hm 2,4-year enclosure,and 11-year enclosure)on vegetation community structure and soil moisture characteristics of alpine meadows on the southern slope of the Qilian Mountains.The results showed that the vegetation height,coverage,aboveground biomass of vegetation exhibited an initial increase followed by a subsequent decrease in response to the duration of grazing prohibition,while the belowground biomass and total biomass exhibited an opposite trend.Compared to the control,the 4-year enclosure treatment resulted in significant increases in vegetation height and coverage(P<0.05),and the aboveground biomass increased by 45.95%,accompanied by a 4.71%and 9.00% decline in belowground biomass and total biomass(P<0.05),respectively.However,the 11-year enclosure treatment significantly decreased vegetation height,coverage,and aboveground biomass,along with a 13.88% and 18.50% rise in belowground biomass and total biomass(P<0.05),respectively,relative to the 4-year enclosure treatment.Although the species number of vegetation community remained unchanged with the duration of grazing prohibition time,the community structure exhibited significant changed.The plant diversity index and evenness index of 11-year grazing enclosure plots decreased significantly by 11.01%(P<0.05)and 4.20%,respectively,while the dominance index increased by 40.28% compared to the control.The short-term(4-year enclosure treatment)grazing prohibition primarily impacted the maximum water holding capacity,capillary water holding capacity and saturated hydraulic conductivity in the 0~30 cm soil layer.Over the course of enclosure,these parameters,along with soil capillary porosity and total porosity in the 0~30 cm soil layer initially increased before declining,whereas non-capillary porosity had no significant change.In conclusion,a short-term grazing prohibition facilitated the restoration of vegetation community st

关 键 词：禁牧 植物群落结构 土壤水分 持水量 孔隙度 

分 类 号：S812[农业科学—草业科学]