2025-04-10 中国科学院(CAS)
中国科学院応用生態研究所の研究チームは、劣化した草原の回復において、微小な土壌生物、特に20マイクロメートル未満のサイズの菌類が重要な役割を果たすことを明らかにしました。研究では、ドナーサイトから採取した土壌を一度だけ導入した後、4年が経過しても、これらの微生物が土壌の微生物構成や植物の成長に持続的な影響を与えていることが確認されました。この「レガシー効果」は、導入する土壌の量と微生物の組成によって左右されることが示され、効果的な生態系修復戦略の設計には、導入土壌の量と微生物の組成の両方を考慮する必要があることが示唆されました。この研究成果は、微小な土壌生物が長期的な生態系の回復において果たす重要な役割を強調しています。
<関連情報>
- https://english.cas.cn/newsroom/research_news/earth/202504/t20250411_1041019.shtml
- https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2435.70019
劣化した草地における土壌添加の遺産を駆動する小型土壌生物 Small-sized soil organisms drive the legacy of soil addition in a degraded grassland
Yuhui Li, Yixin Sun, Yingbin Li, Xu Han, Bing Li, Xiaofang Du, Qi Li, T. Martijn Bezemer
Functional Ecology Published: 06 March 2025
DOI:https://doi.org/10.1111/1365-2435.70019
Abstract
- Plants can alter the abiotic and biotic components of the soil ecosystem, and this can result in soil legacies that facilitate or inhibit the growth of succeeding plants. To what extent soil legacy effects are due to soil biotic or abiotic characteristics is still poorly understood.
- In a microcosm experiment, we grew one plant species (Leymus Chinensis) in soil containing legacy effects of a prior soil inoculation event where soil from donor sites was inoculated at a receiver site. We tested whether soil legacies originating from the field plots differentially shaped the assemblage of soil microbial communities and plant performance, and how these effects are changed by the removal of specific size groups of soil biota.
- Our microcosm experiment showed that soil legacies from a one-time soil addition experiment in a degraded grassland can affect the soil microbial composition 4 years later. This legacy effect was positively influenced by the amount of soil originally added to the field plot. By testing four types of biotic fractions differing in size, we found that small-sized organisms (<20 μm), in particular fungi, were the most important for legacy formation and plant growth.
- Our results highlight the importance of inoculum density and smaller-sized microbes in the formation of soil legacies. We conclude that the interaction between plant and soil microbes is a driver in the restoration of degraded grassland after soil addition. Disentangling the contributions of different biotic groups in the soil to plant growth can provide a theoretical basis for the preparation of bio-inoculants that can be used for the sustainable restoration of degraded ecosystems.
