不同放牧强度对荒漠草原土壤呼吸速率及其温度敏感性的影响  

Effects of Different Grazing Intensities on Soil Respiration Rate and its Temperature Sensitivity in Desert Steppe

作　　者：宁玉娜 王占义 高翠萍[1,2] 吕广一 杨昌祥[3] 张春英 王成杰 NING Yu-na;WANG Zhan-yi;GAO Cui-ping;LYU Guang-yi;YANG Chang-xiang;ZHANG Chun-ying;WANG Cheng-jie(College of Grassland Resource and Environment,Inner Mongolia Agricultural University,Hohhot,Inner Mongolia 010011,China;Key Laboratory of Grassland Resources of the Ministry of Education,Inner Mongolia Agricultural University,Hohhot,Inner Mongolia 010011,China;Forestry and Grassland Bureau,Hade County,Ulanqab City,Inner Mongolia,Ulanqab,Inner Mongolia 012000,China)

机构地区：[1]内蒙古农业大学草原与资源环境学院,内蒙古呼和浩特010011 [2]内蒙古农业大学草地资源教育部重点实验室,内蒙古呼和浩特010011 [3]内蒙古乌兰察布市化德县林业与草原局,内蒙古乌兰察布012000

出　　处：《草地学报》2024年第10期3233-3240,共8页Acta Agrestia Sinica

基　　金：内蒙古自治区“科技兴蒙”国际合作引导项目“退化草原改良与放牧利用固碳减排技术集成与转化”(2021CG0020);内蒙古自治区自然科学基金项目(2024MS03005);国家自然科学基金项目“放牧对内蒙古荒漠草原生态系统稳定碳同位素分馏/富集机制的研究”(31960357)资助。

摘　　要：在气候变暖影响下,研究放牧对草原土壤呼吸速率(Soil respiration rate,Rs)及其温度敏感性系数(Temperature sensitivity,Q 10)的影响,对阐述草原生态系统碳收支具有重要意义。以荒漠草原为研究对象,设置无牧、轻度放牧和重度放牧3个处理,运用全自动变温培养土壤温室气体在线测量系统,测定不同放牧处理区0~30 cm土壤变温(-10~25℃)培养下的呼吸速率并计算Q 10。结果表明:放牧处理9年后的Rs及其Q 10值为:重度放牧Rs显著高于无牧和轻度放牧(P<0.05),重度放牧显著增加0~10 cm土层Q 10值;与无牧相比,轻度放牧显著降低20~30 cm土层Q 10值;主成分分析表明:放牧强度主要影响土壤pH值、粉粒含量,进而影响Rs。轻度放牧可降低土壤呼吸Q 10值,从而减少荒漠草原土壤CO_(2)排放。因此,建议实施轻度放牧管理策略以减少荒漠草原的碳排放。Under the influence of climate warming,it is crucial to investigate the impacts of grazing on soil respiration rate and temperature sensitivity coefficient(Q 10)in grassland ecosystems for carbon budget equilibrium.Taking desert steppe as the research subject,three treatments were established:no grazing,light grazing,and heavy grazing.An automated greenhouse gas online measurement system was employed to evaluate the respiration rate of 0-30 cm soil under varying temperatures(-10-25℃)in different grazing treatment areas and calculate Q 10.The findings were as follows:After 9 years of grazing treatment,the soil respiration rate and its temperature sensitivity coefficient Q 10 exhibited significant differences among treatments.Heavy grazing resulted in significantly higher soil respiration rates compared to no grazing and light grazing(P<0.05).Heavy grazing notably increased the Q 10 value within the 0-10 cm soil layer,while light grazing significantly decreased the Q 10 value within the 20-30 cm soil layer.Principal component analysis showed that the grazing intensity mainly affected soil pH value,the content of silt,and then affected soil respiration rate.Light grazing can reduce the temperature sensitivity of soil respiration and reduce soil CO_(2) emissions in desert steppe.Light grazing reduces soil respiration Q 10 values and thus reduces CO_(2) emissions from desert grassland soils.Therefore,it is recommended to implement light grazing management strategies to reduce carbon emissions from desert grasslands.

关 键 词：荒漠草原 放牧强度 土壤呼吸速率 温度敏感性 

分 类 号：S812.2[农业科学—草业科学]