华东师范大学周小奇团队近日揭示了增强植物多样性可减少全球森林土壤中的一氧化二氮排放。这一研究成果于2025年5月13日发表在《国家科学评论》杂志上。

森林被公认为陆地上一氧化二氮（N₂O）排放的最大自然来源，森林砍伐大大降低了全球原生森林的覆盖率和生物多样性。然而，森林生物多样性的丧失如何影响土壤N₂O通量仍然知之甚少。研究组结合了一个全球树木多样性森林土壤N₂O数据集，其中包括来自全球森林的201对可比观测数据，以及一项为期三年的现场调查，该调查收集了长期植物多样性现场实验的现场通量数据。该分析表明，树木多样性对土壤N₂O排放有显著的负面影响，主要是由于与反硝化相关的N₂O产量减少。 

更具体地说，研究组表明，树木多样性导致的N₂O排放减少可归因于土壤无机氮可用性的降低。预测模型进一步表明，与单一树种相比，拥有两种树种的森林可以减少10.39%的全球N₂O排放，而拥有24种树种的树木可以实现最大的减排效果，减少56.30%的排放。总之，该工作强调了树木多样性对减少N₂O排放的贡献，强调了在重新造林老森林和支持新造林过程中考虑生物多样性的重要性。

附：英文原文

Title: Enhanced plant diversity reduces nitrous oxide emissions in forest soils worldwide

Author: Zuo, Hanling, Xiao, Wensheng, Dong, Mingqiu, Gu, Xinyun, Liang, Xia, Smith, Pete, Baquerizo, Manuel Delgado, Hou, Lijun, Zhou, Xiaoqi

Issue&Volume: 2025-05-13

Abstract: Forests are recognized as the largest natural source of nitrous oxide (N2O) emissions on land, with deforestation drastically reducing the cover and biodiversity of native forests worldwide. Yet, how losses in forest biodiversity affect soil N2O fluxes remains poorly understood. Here, we combined a global tree diversity-forest soil N2O dataset, including 201 paired comparable observations from global forests, with a three years field survey of in-situ fluxes data gathered from a long-term plant diversity field experiment. Our analyses reveal that tree diversity has a significant negative effect on soil N2O emissions, primarily driven by a decrease in N2O production associated with denitrification. More specifically, we showed that reductions in N2O emissions with tree diversity can be attributed to a decrease in the availability of soil inorganic nitrogen. Predictive modeling further shows that compared to single tree species, forests with two tree species can reduce global N2O emissions by 10.39%, while those with 24 tree species achieve the maximum mitigation effect, reducing emissions by 56.30%. Taken together, our work highlights the contribution of tree diversity for mitigating N2O emissions, highlighting the importance of accounting for biodiversity when reforesting old forests, and while supporting new afforestation processes.

DOI: 10.1093/nsr/nwaf186

Source: https://dx.doi.org/10.1093/nsr/nwaf186