樹木の多様性が森林土壌の炭素と窒素の貯蔵量を増加させ、気候変動を緩和することが判明(Study: Tree diversity increases storage of carbon and nitrogen in forest soils, mitigating climate change)

2023-04-26 ミシガン大学

＜関連情報＞

• https://news.umich.edu/study-tree-diversity-increases-storage-of-carbon-and-nitrogen-in-forest-soils-mitigating-climate-change/
• https://www.nature.com/articles/s41586-023-05941-9

樹木の多様性は10年後の森林土壌の炭素と窒素の発生を増加させる Tree diversity increases decadal forest soil carbon and nitrogen accrual

Xinli Chen,Anthony R. Taylor,Peter B. Reich,Masumi Hisano,Han Y. H. Chen & Scott X. Chang
Nature  Published:26 April 2023
DOI:https://doi.org/10.1038/s41586-023-05941-9

Abstract

Increasing soil carbon and nitrogen storage can help mitigate climate change and sustain soil fertility^1,2. A large number of biodiversity-manipulation experiments collectively suggest that high plant diversity increases soil carbon and nitrogen stocks^3,4. It remains debated, however, whether such conclusions hold in natural ecosystems^{5,6,7,8,9,10,11,12}. Here we analyse Canada’s National Forest Inventory (NFI) database with the help of structural equation modelling (SEM) to explore the relationship between tree diversity and soil carbon and nitrogen accumulation in natural forests. We find that greater tree diversity is associated with higher soil carbon and nitrogen accumulation, validating inferences from biodiversity-manipulation experiments. Specifically, on a decadal scale, increasing species evenness from its minimum to maximum value increases soil carbon and nitrogen in the organic horizon by 30% and 42%, whereas increasing functional diversity enhances soil carbon and nitrogen in the mineral horizon by 32% and 50%, respectively. Our results highlight that conserving and promoting functionally diverse forests could promote soil carbon and nitrogen storage, enhancing both carbon sink capacity and soil nitrogen fertility.