摘要
为探究草地土壤呼吸及其组分对不同刈割强度的响应,本试验以山西省右玉县农牧交错带典型草地生态系统为研究对象,于2016年按照留茬高度设置4个刈割强度(不刈割、轻度刈割(留茬10 cm)、中度刈割(留茬5 cm)和重度刈割(留茬2 cm)),用浅环和深环区分草地土壤的总呼吸和异养呼吸,分别在2017和2018年的5—9月利用Li-840静态箱法测定土壤呼吸速率。研究结果表明:土壤呼吸及其组分的速率受土壤温度的调控表现出明显的季节动态,峰值均出现在8月初;刈割主要通过影响土壤异养呼吸对土壤总呼吸产生影响;轻度刈割有降低土壤呼吸及其组分速率的趋势,在中度刈割下,土壤异养呼吸速率有增加趋势,而土壤自养呼吸速率有降低的趋势,土壤总呼吸速率没有明显变化,在重度刈割下,土壤总呼吸和异养呼吸的速率均有增加的趋势,而土壤自养呼吸的速率呈降低趋势。因此,中度刈割对土壤CO2的排放影响较小,建议中国北方农牧交错带典型草地割草利用留茬5 cm。
In order to investigate the response of soil total respiration(SRtot)and its components(Soil heterotrophic respiration(SRh)and autotrophic respiration(SRa))to different mowing intensities,an experimental study was conducted in 2016 in the agro-pastoral ecotone in Youyu,Shanxi Province.Four treatments were set up according to stubble heights:no mowing(NM),light mowing(LM,stubble 10 cm),moderate mowing(MM,stubble 5 cm),and heavy mowing(HM,stubble 2 cm).SRh and SRtot were distinguished with deep-shallow PVC collars method,which were determined by Li-840 static chamber method in 2017 to 2018.Results showed that SRtot and its components presented obvious seasonal dynamics,and the peaks appeared at the beginning of August,which were mainly regulated by soil temperature.Mowing influenced SRtot by affecting SRh.Light mowing had a tendency to reduce the rates of SRtot and its components.Moderate mowing had no significant effect on SRtot due to the offset of the increase of SRh and the decrease of SRa.Under heavy mowing,the rates of SRtot and SRh were both increased,while SRa was decreased.Therefore,moderate mowing has comparatively lesser impact on soil CO2 emission.It is suggested that mowing at the stubble of 5 cm should be relatively appropriate for the typical grassland in the agro-pastoral ecotone of northern China.
作者
王惠玲
刁华杰
崔乐乐
薄元超
刘夏琳
任雨佳
郝杰
李扬
申颜
王常慧
董宽虎
WANG Hui-ling;DIAO Hua-jie;CUI Le-le;BO Yuan-chao;LIU Xia-lin;REN Yu-jia;HAO Jie;LI Yang;SHEN Yan;WANG Chang-hui;DONG Kuan-hu(College of Grassland Science, Shanxi Agricultural University, Taigu, Shanxi Province 030801, China;State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China)
出处
《草地学报》
CAS
CSCD
北大核心
2020年第5期1403-1411,共9页
Acta Agrestia Sinica
基金
国家自然科学基金面上项目(31770526,31872406)
国家重点研发计划子课题(2016YFC0500703)资助。
关键词
农牧交错带
刈割强度
土壤呼吸
典型草地
Agro-pastoral ecotone
Mowing intensity
Soil respiration
Typical grassland
