摘要
【目的】受气候变化和人类活动影响,青藏高原生态安全屏障仍然面临退化草地面积大、固碳能力降低等生态风险。揭示放牧对青藏高原高寒草地土壤有机碳含量影响及调控因素,对于提升高寒草地生态屏障功能具有重要作用。【方法】采用Meta分析,明晰不同放牧强度对青藏高原土壤有机碳含量、理化性质影响的平均效应值,结合混合效应模型,揭示放牧对土壤有机碳影响效应的主要调控因素。【结果】放牧干扰极显著降低高寒草地土壤有机碳含量,降幅约13.93%,平均效应值-0.15±0.04(P<0.001)。轻度、中度和重度放牧草地土壤有机碳降幅分别为12.19%、13.06%和15.63%,轻度放牧处理未达到显著性检验水平。放牧干扰显著降低高寒草地土壤速效钾、全磷、全氮和全钾含量,降幅分别为14.55%、10.74%、9.14%(P<0.01)和3.17%(P<0.05)。放牧显著增加速效氮含量和土壤容重,增幅分别为11.90%和12.66%。放牧草地土壤有机碳效应值,主要受土壤速效钾、全氮含量、土壤容重和海拔影响,均达到显著性检验水平,效应值变异的解释强度为69.73%。【结论】轻度放牧提高土壤速效钾含量,有利于降低放牧引起的青藏高原高寒草地碳排放量。
【Objective】The ecological security barrier of the Qinghai Tibet Plateau still faces ecological risks such as large degraded grassland area and reduced carbon sequestration capacity,because of climate change and human activities.Revealing the influence and regulation factors of grazing on soil organic carbon content of alpine grass-land in Qinghai-Tibet Plateau plays an important role in improving the ecological barrier function of alpine grassland【Method】Meta-analysis was used to clarify the average effect values of different grazing intensities on soil organic carbon content and physicochemical properties on the Qinghai-Tibet Plateau.Combined with the mixed effects model,the main regulatory factors of grazing effects on soil organic carbon were revealed.【Result】This study revealed that grazing disturbance significantly reduced the content of soil organic carbon in alpine grassland approxi-mately 13.93%.Meanwhile,the average effect size was-0.15±0.04(P<0.001).The decrease of soil organic carbon in light,moderate and heavy grazing grasslands was 12.19%,13.06%and 15.63%respectively.But the effect of light grazing treatment was insignificant.Grazing disturbance significantly reduced the contents of soil available potassium,total phosphorus,total nitrogen,and total potassium in alpine grasslands by 14.55%,10.74%,9.14%(P<0.01)and 3.17%(P<0.05),respectively..Grazing activity significantly increased the content of available nitrogen and bulk density by 11.90%and 12.66%respectively.The effect size of soil organic carbon was mainly driven by soil available potassium,total nitrogen,bulk density,and altitude in grazing grassland(P<0.05).The total explanatory intensity of effect value variation reached 69.73%.【Conclusion】Light grazing and increasing the content of soil available potassium are beneficial to alleviate the effect of grazing on soil carbon content of alpine meadows in the Qinghai Tibet Plateau.
作者
王灵艳
杜岩功
许庆民
王云英
曲家鹏
WANG Ling-yan;DU Yan-gong;XU Qing-min;WANG Yun-ying;QU Jia-peng(Industry Development and Planning Institute,National Forestry and Grassland Administration,Beijing 100010,China;Northwest Institute of Plateau Biology,Chinese Academy of Science,Xining 810008,China;Qinghai ecological environment monitoring center,Xining 810008,China)
出处
《草原与草坪》
CAS
CSCD
2023年第3期21-27,共7页
Grassland and Turf
基金
国家自然科学基金联合基金项目(U21A20186)
中科院西部之光交叉团队项目(E129351214)
青海省重点研发与转化计划项目(2022-NK-135)
青海省昆仑英才“领军人才”项目[青人才字(2021)13号]。
