Investigation of nitrate utilization in a boreal forest ecosystem using nitrogen isotope analysis

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K06142
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 40010:Forest science-related
• Research Institution: Shinshu University
• Principal Investigator: Oda Ayumi 信州大学, 学術研究院農学系, 助手 (40571609)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 窒素同位体比 / 北方林 / 硝酸態窒素 / 窒素利用

Outline of Final Research Achievements

In this study, we investigated the role of nitrate as a nitrogen source for trees and the plasticity of their ability to uptake nitrogen, which has not been considered as a nitrogen source for forest trees in boreal forests or in low-temperature environments at high elevations. As a result, the absorptive capacity of nitrate-nitrogen differed among tree species, and even among tree species using nitrate-nitrogen absorption, the amount of nitrate-nitrogen absorbed varied depending on the growth environment, such as elevation. Nitrate requires more energy for assimilation than other forms of nitrogen. This study showed that forest trees in low temperature and oligotrophic environments adjust their ability to use and absorb nitrate according to their growth environment.

Free Research Field

樹木生理生態学、森林科学

Academic Significance and Societal Importance of the Research Achievements

本研究により、これまで土壌中の存在量が少なく、通常の分析では検出が難しかった硝酸態窒素の樹種ごとの利用実態を明らかにし、北方林樹木の生産性に関わる土壌からの窒素吸収モデルを精緻化できる可能性がある。