Elucidation of rhizospheric consortium responses to two gradients of climate and soil acidity

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H02232
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 40010:Forest science-related
• Research Institution: Mie University
• Principal Investigator: Matsuda Yosuke 三重大学, 生物資源学研究科, 教授 (30324552)
• Co-Investigator(Kenkyū-buntansha): 谷川 東子 名古屋大学, 生命農学研究科, 准教授 (10353765) ; 北上 雄大 三重大学, 生物資源学研究科, 助教 (40882684) ; 小長谷 啓介 国立研究開発法人森林研究・整備機構, 森林総合研究所, 主任研究員 等 (90612739)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: スギ / 細根 / 真菌 / 細菌 / 線虫 / 窒素

Outline of Final Research Achievements

Environmental disturbances due to climate change and soil acidification are causing a decline in the functioning of forest ecosystems worldwide. In this study, tree roots, mycorrhizal fungi, bacteria and nematodes were considered as a rhizosphere consortium, and the aim was to clarify the effects of different climatic zones and soil acidification on this consortium. The rhizosphere fungal and bacterial communities and soil nematodes of cedar plantations in cool-temperate to subtropical regions were significantly affected by the soil environment inhabited. A 2.5-year incubation experiment using cedar roots and leaves as substrates showed that nitrate was the predominant nitrogen form in the root leachate, with a cumulative amount 22.6 times higher than in the leaf leachate. Bacterial communities were associated with nitrate concentration and leachate pH, whereas changes in fungal community structure were associated with leachate pH.

Free Research Field

森林微生物

Academic Significance and Societal Importance of the Research Achievements

本研究は，スギ人工林における樹木細根を取り巻く土壌生物の動態を包括的に解き明かし，見えない地下部の生物多様性に関して有用な視点を提供した．さらに器官特異的なリターの窒素動態と関わる微生物を理解することで、窒素循環を予測するための視点を提供した．以上の情報は，局所的および地球規模の環境変化に対する森林生態系の応答，健全性を予測するための基礎情報を提供する．