放牧和刈割对山地草原植被多样性和凋落物分解的影响  

Effects of Grassland Use Patterns on Vegetation Diversity and Litter Decomposition in Xiejiagou Region on the Northern Slope of Tianshan Mountains

作　　者：王永琪 李维思 张树振[1] 阿斯娅·曼力克[2] 胡晓静 孙群策 张博[1] WANG Yong-qi;LI Wei-si;ZHANG Shu-zhen;Asiya Manlike;HUXiao-jing;SUN Qun-ce;ZHANG Bo(College of Grassland Science,Xinjiang Agricultural University,Urumqi 830052,China;Institute of Grassland Research,Xinjiang Academy of Animal Science,Urumqi 830000,China)

机构地区：[1]新疆农业大学草业学院,乌鲁木齐830052 [2]新疆畜牧科学院草业研究所,乌鲁木齐830000

出　　处：《新疆农业大学学报》2023年第2期107-116,共10页Journal of Xinjiang Agricultural University

基　　金：国家牧草产业技术体系项目(CARS34);新疆维吾尔自治区草学高峰学科项目。

摘　　要：为探究天山北坡谢家沟区域草地利用模式对草地植被多样性和凋落物分解(土壤碳输入)的影响,本研究以天山北坡中段乌鲁木齐县谢家沟的山地草原为研究对象,以放牧(载畜量2.8羊单位/hm^(2))和刈割为试验处理,采用样方法和凋落物原位分解法对放牧、刈割草地的植被α多样性、凋落物分解动态进行测定,同时对凋落物分解过程中的土壤表面和10 cm温度、土壤水分、容重、辐照度等环境因子进行监测。结果表明,放牧降低了草地植被的高度、盖度、地上生物量,同时其植被多样性指数、丰富度指数、均一性指数显著低于刈割草地(P<0.05);地上凋落物分解速率显著高于地下凋落物(根系)(P<0.05);放牧显著降低了地上、地下凋落物的分解速率,同时相较于刈割处理,放牧降低了土壤水分,增加了土壤温度、土壤容重和辐照度(P<0.05);冗余分析(RDA)表明,水分是该区域限制凋落物分解的主要因素。天山北坡谢家沟区域刈割利用维持了草地植被多样性,同时其凋落物分解碳输入也没有受到抑制,而放牧利用使得草地植被多样性下降,抑制了作为碳输入的凋落物分解过程。To explore the influence of grassland utilization mode on grassland vegetation diversity and decomposition of litter(soil carbon input).The research object for this study is the upland grassland in Xiejiagou,Urumqi County,which is located in the middle part rof the north slope of the Tianshan Mountains.Cutting and grazing were utilized as experimental treatments with 2.8 standard sheep units/hm^(2) of livestock capacity.The designation of a grazing sample plot and a cutting sample plot was made based on the existing state of local grassland usage to measure diversity and dynamics of litter decomposition while keeping an eye on environmental factors like soil surface temperature,soil 10 cm temperature,soil moisture,bulk density,and irradiance during the decomposition cycle.This analysis was done on the vegetation of the grazing and cutting grasslands.The findings demonstrated that grazing decreased the height,coverage and aboveground biomass of grassland vegetation,while its vegetation diversity index,richness index,and uniformity index were significantly lower than those of mowed grassland(P<0.05);[CDF10]The decomposition rate of aboveground litter was significantly higher than that of underground litter(underground roots)(P<0.05);Redundancy analysis(RDA)showed that water was the main factor limiting litter decomposition in this area.Grazing significantly reduced the decomposition rate of aboveground and underground litter,while grazing reduced soil moisture and increased environmental indicators like soil temperature,soil bulk density,and irradiance(P<0.05)compared to mowing treatment.In conclusion,the mowing in the Xiejiagou area on the northern slope of Tianshan Mountain maintained the diversity of grassland vegetation,while the carbon input of litter decomposition was not inhibited,while the grazing utilization reduced the diversity of grassland vegetation,which inhibited the decomposition process of litter as carbon input.

关 键 词：山地草原 放牧 刈割 植被多样性 土壤环境因子 凋落物 

分 类 号：S812.8[农业科学—草业科学]