全球氮沉降持续威胁着植物多样性和生态系统的稳定,尽管其增长速度最近有所放缓。不稳定碳(C)可能通过减轻微生物碳饥饿来帮助减少过量氮,但它们在减轻氮富集有害影响方面的作用尚不清楚。在中国北方的草甸草原上,我们进行了为期9年(2014-2022)的6个历史N添加水平(0、2、5、10、20和50 g N m−2年−1,2014-2019)和3个稳定C水平(0、200和2000 g C m−2年−1)的田间试验。停止施氮3年后(2020-2022年),氮肥处理下的地上净初级生产力(ANPP)保持较高水平。然而,随着施氮量的增加,物种丰富度和群落稳定性持续下降。添加不稳定C降低了群落内某些植物的优势度,但增加了物种的非同常性和地下净初级生产力(BNPP)。增强回归树模型表明,高水平的不稳定碳输入通过提高BNPP来提高群落稳定性,随着不稳定碳输入的增加,BNPP对群落稳定的相对重要性从7.5%增加到27.4%。合成。我们的研究结果强调了不稳定的碳输入如何通过增强植物-微生物竞争和增加地下生物量分配来抵消氮富集对群落稳定性的负面影响。
期刊介绍:
Journal of Ecology publishes original research papers on all aspects of the ecology of plants (including algae), in both aquatic and terrestrial ecosystems. We do not publish papers concerned solely with cultivated plants and agricultural ecosystems. Studies of plant communities, populations or individual species are accepted, as well as studies of the interactions between plants and animals, fungi or bacteria, providing they focus on the ecology of the plants.
We aim to bring important work using any ecological approach (including molecular techniques) to a wide international audience and therefore only publish papers with strong and ecological messages that advance our understanding of ecological principles.