刈割对草甸草原土壤微生物化学计量特征的影响  

Effects of mowing on soil microbial stoichiometry in meadow grassland

作　　者：石田 曹娟 闫瑞瑞[2,3] 闫玉春 张煜星[1] 王旭 辛晓平 SHI Tian;CAO Juan;YAN Rui-rui;YAN Yu-chun;ZHANG Yu-xing;WANG Xu;XIN Xiao-ping(Academy of Forest and Grassland Inventory and Planning,National Forestry and Grassland Administration,Beijing 100714;Institute of Agricultural Resources and Regional Planning of Chinese Academy of Agricultural Sciences,Beijing 100081;Hulunber Grassland Ecosystem Research Station,Hailaer Inner Mongolia 021012)

机构地区：[1]国家林业和草原局调查规划设计院,北京100714 [2]中国农业科学院农业资源与农业区划研究所,北京100081 [3]呼伦贝尔草原生态系统国家野外科学观测研究站,内蒙古海拉尔021012

出　　处：《中国土壤与肥料》2023年第3期127-134,共8页Soil and Fertilizer Sciences in China

基　　金：国家自然基金面上项目(31971769,32130070,32171567);中央级公益性科研院所基本科研业务费专项(Y2020YJ19,1610132021016);农业科技创新联盟建设-农业基础性长期性科技工作(NAES037SQ18);财政部和农业农村部:国家现代农业产业技术体系。

摘　　要：以内蒙古呼伦贝尔草甸草原作为研究对象,探讨土壤微生物化学计量特征在不同刈割频次处理下的变化规律,以期为草原资源的可持续利用提供理论依据。试验设有6个处理,对照区(CK)、1年1割(M1)、2年1割(M2)、3年1割(M3)、6年1割(M6)和12年1割(M12),每个刈割处理设置3个重复。2018年8月中旬在样地内随机设置3个样方,在样方内随机设置3个取样点,分别按0~10、10~20、20~30 cm土层进行均一采样,将土样按层次充分混合并带回实验室,采用氯仿熏蒸法对样品进行处理后,进行土壤微生物生物量碳(MBC)、氮(MBN)、磷(MBP)含量的测定。研究结果表明:刈割没有显著影响MBC、MBN、MBP含量及其化学计量比,表明刈割处理下微生物系统具有相对的稳定性。从6个处理的平均值整体来看,MBC、MBN、MBP含量以及微生物生物量C∶N、C∶P(MBC∶N、MBC∶P)随刈割间隔延长呈现先升高后下降的趋势,并在M2和M3处最高;本研究区各处理梯度MBC∶P平均值大于30,比值较高,微生物生物量N∶P(MBN∶P)低于全球平均水平(6.9或5.6)。由于刈割一般在生长季后期进行,对草原生态系的影响比传统刈割要小得多,因此对MBC、MBN、MBP含量及其化学计量比的影响不明显,但适当的刈割不仅利于微生物的繁殖和根系的生长,而且对草原生态系统生产力以及植被群落产生积极影响,进而影响草地生态系统的结构和功能,因此应进行适宜的刈割。Taking the Hulunber meadow grassland in Inner Mongolia as the research object,the change law of the stoichiometric characteristics of soil microorganisms in different mowing frequency treatments was discussed so as to provide theoretical basis for the sustainable use of grassland resources.The six different mowing treatments were set up,including control(CK),the one-cut-once-a-year treatment(M1),the one-cut-every-two-years treatment(M2),the one-cut�every-three-years treatment(M3),the one-cut-every-six-years treatment(M6),and the one-cut-every-twelve-years treatment(M12).Each treatment had three repetitions.Three quadrats were selected in each plot in the middle of August,2018,and three sampling points were randomly chosen,which were uniformly sampled at 0~10,10~20 and 20~30 cm,respectively.The soil samples were fully mixed according to the layers and brought back to the laboratory.After the samples were treated by chloroform fumigation,the soil microbial biomass carbon(MBC),nitrogen(MBN)and phosphorus(MBP)were determined.The results showed that mowing treatments did not significantly affect the contents of MBC,MBN,MBP and their stoichiometric ratio,indicating that the microbial system had relative stability under mowing treatments.From the average values of the six treatments as a whole,the contents of MBC,MBN,MBP and the C∶N and C∶P of the microbial biomass(MBC∶N,MBC∶P)showed a trend of first increasing and then decreasing with the extension of the mowing interval,and reached the highest at M2 and M3.The average value of MBC∶P in each treatment in this experiment area was greater than 30,which was of a high ratio.The microbial biomass N∶P(MBN∶P)was lower than the global average level(6.9 or 5.6).Because the mowing in this study was generally carried out in the late growing season,the impact on grassland ecosystem was much smaller than traditional mowing,the impact on soil microbial biomass and its stoichiometric ratio was not obvious.However,appropriate mowing is not only conducive to microbial r

关 键 词：刈割 土壤微生物 微生物生物量碳 微生物生物量氮 微生物生物量磷 化学计量特征 

分 类 号：S812.2[农业科学—草业科学]