放牧强度对黄土丘陵区草地植物群落特征的影响  

Effects of Grazing Intensity on the Grassland Vegetation Community Characteristics in the Hilly Loess Plateau Region

作　　者：孙会 赵允格 刘广亮 高丽倩[2] 王鹏 马昕 李雯 许明祥[2] SUN Hui;ZHAO Yun-ge;LIU Guang-liang;GAO Li-qian;WANG Peng;MA Xin-xin;LI Wen;XU Ming-xiang(College of Forestry, Northwest A&F University, Yangling, Shaanxi Province 712100, China;Institute of Soil and Water Conservation, Northwest A & F University, Yangling, Shaanxi Province 712100, China;College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi Province 712100, China;Wuqi County Returning Farmland to Forest Ecological (Forest) Park Management Office, Wuqi Shaanxi Province 717600, China)

机构地区：[1]西北农林科技大学林学院,陕西杨凌712100 [2]西北农林科技大学水土保持研究所,陕西杨凌712100 [3]西北农林科技大学资源与环境学院,陕西杨凌712100 [4]吴起县退耕还林生态(森林)公园管理处,陕西吴起717600

出　　处：《草地学报》2022年第4期810-817,共8页Acta Agrestia Sinica

基　　金：中国科学院“西部之光”交叉团队项目-重点实验室合作研究专项(2019);国家自然科学基金项目(41907056,41830758)资助。

摘　　要：退耕还林(草)工程实施后,黄土丘陵区形成大面积草地,该草地的可持续管理备受关注。适度放牧可能有利于草地植物群落的自然更新及可持续发展,同时可增加经济收入,但该区鲜见相关报道。为此,本文以该区20年以上退耕草地为研究对象,通过野外调查,研究了不同放牧强度(以单位面积羊粪球数量表征)对草地植物群落特征的影响。结果表明:轻度放牧(粪球密度为0~10个·m^(-2))可促进退耕草地植物群落发育,群落平均高度、盖度、生物量、Shannon-Wiener指数和Margalef指数较封禁草地分别增加了39.8%,5.0%,26.0%,14.8%和32.8%。放牧超过一定强度(粪球密度大于10个·m^(-2))将导致退耕草地植物群落退化,群落平均高度、盖度、生物量、Shannon-Wiener指数和Margalef指数较封禁草地分别降低了48.0%,24.2%,63.1%,14.3%和27.0%。在一定放牧强度(15~20个·m^(-2))下植物群落中直立、丛生生活型物种优势度降低,莲座和匍匐生活型物种优势度增加,耐牧性增强。本研究可为黄土丘陵区大面积退耕草地的可持续管理提供参考。Large area of revegetated grassland was formed in the Hilly Loess Plateau region since the implementation of the project“Grain for Green”.Nowadays,how to sustainably manage this grassland became an important issue.Moderate grazing may benefit the natural regeneration and sustainable development of grassland vegetation communities,and increase the economic income.However,there are few studies focused on the issue in this area currently.Accordingly,this study investigated the effects of different grazing intensities(which was expressed in the goat’s dung density in the study)on the characteristics of vegetation communities in the Hilly Loess Plateau region.The results showed that:(1)Light grazing(dung ball density was 0~10 individual·m^(-2))promoted the development of vegetation communities in the revegetated grasslands.Compared with enclosed grassland,the average height,coverage,biomass,the Shannon-wiener index and the Margalef richness of the vegetation communities were increased by 39.8%,5.0%,26.0%,14.8%and 32.8%,respectively.(2)It led to the degradation of the vegetation community of the grassland when grazing exceeds a certain intensity(dung ball density was 10 individual·m^(-2)).The average height,coverage,biomass,Shannon-wiener index and the Margalef richness of the vegetation communities decreased by 48.0%,24.2%,63.1%,14.3%and 27.0%respectively compared with that of the enclosed grassland.(3)Under a certain grazing intensity(15~20 individual·m^(-2)),the dominance of standing and clumping living species in the community were decreased,while the dominance of rosettes and creeping species were increased,the grazing tolerance was therefore enhanced.The results would provide a reference for the sustainable management of a large-scale revegetated grassland in this area.

关 键 词：放牧 粪球密度 植被群落 物种组成 生物量 物种多样性 

分 类 号：S153[农业科学—土壤学]