Precipitation and land use alter soil respiration in an Inner Mongolian grassland
Precipitation and land use alter soil respiration in an Inner Mongolian grassland
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DOI：
10.1007/s11104-022-05638-4
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发表时间：
2022-08
期刊：
影响因子：
4.9
通讯作者：
Chi Zhang;Chao Song;Donghui Wang;Wen-geng Qin;Biao Zhu;F. Li;Yonghui Wang;Wenhong Ma
中科院分区：
文献类型：
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作者：
Chi Zhang;Chao Song;Donghui Wang;Wen-geng Qin;Biao Zhu;F. Li;Yonghui Wang;Wenhong Ma
目的草原正面临气候变化和土地集约利用的威胁。草原生态系统中的土壤呼吸（Rs）可能会因降水和土地利用的变化而改变。我们的目的是量化内蒙古草原降水变化和常见土地利用方式（即割草和放牧）对土壤呼吸的影响。方法我们进行了改变降水（+ 50%、环境和-50%）和土地利用（控制或围栏、割草和放牧）的原位实验，以探讨它们对土壤呼吸及其自养（Ra）和异养（Rh）的影响结果降水变化对非生物和生物驱动因素的影响比土地利用更强，从而对 R 及其组成部分产生更强的影响。在为期3年的实验中，随着降水量的减少，Rs、Ra和Rh分别下降了36%、42%和33%，随着降水量的增加，Rs、Ra和Rh分别增加了29%、36%和25%。与围栏相比，放牧和割草造成的 Rs 下降相对较小（通常 < 10%）。然而，降水和土地利用交互影响非生物和生物驱动因素，从而影响卢比。放牧（38%）和割草（37%）导致的 Rs 随降水量减少而下降的幅度大于围栏（32%）。 结论 与围栏相比，在预计降水量减少的情况下，Rs 及其组成部分可能会减少，并且放牧和割草可能会进一步减少。因此，在预测草地碳循环以应对未来降水变化时，应考虑土地利用。
PurposeGrasslands are facing the threat of climate change and intensive land use. Soil respiration (Rs) in grassland ecosystems can be potentially altered by changes in precipitation and land use. We aimed to quantify the impact of changes in precipitation and common land use practices in an Inner Mongolia grassland, i.e., mowing and grazing, on soil respiration.MethodsWe performed anin situexperiment with altered precipitation (+ 50%, ambient, and -50%) and land use (control or fencing, mowing, and grazing) to explore their impacts on soil respiration and its autotrophic (Ra) and heterotrophic (Rh) components.ResultsAltered precipitation had stronger impacts on abiotic and biotic drivers than land use, leading to stronger impacts on Rsand its components. Over the 3-year experiment, Rs, Raand Rhdecreased by 36%, 42% and 33% with reduced precipitation and increased by 29%, 36% and 25% with increased precipitation, respectively. Grazing and mowing caused relatively small decreases in Rscompared to fencing (generally < 10%). However, precipitation and land use interactively impacted abiotic and biotic drivers and thus Rs. The decrease in Rswith reduced precipitation was greater with grazing (38%) and mowing (37%) than with fencing (32%).ConclusionsRsand its components may decrease under the projected decrease in precipitation and may further decrease with grazing and mowing compared to fencing. Therefore, land use should be considered when predicting grassland carbon cycling in response to future precipitation changes.