Ecological value of abandoned farmland in biodiversity conservation of wet grasslands: evaluation using wintering bird community as an indicator

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K15541
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 39060:Conservation of biological resources-related
• Research Institution: Iwate Cultual Promotion Agency
• Principal Investigator: Takahashi Masao 公益財団法人岩手県文化振興事業団(博物館), 学芸第三課, 専門学芸調査員 (10815541)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 生物多様性の保全 / 耕作放棄地 / 湿性草原 / 鳥類 / 絶滅危惧種

Outline of Final Research Achievements

Abandoned rice fields are wet grasslands that have been established within farmland and have provided good habitats for wildlife. However, before their ecological functions and conservation value were noticed, they have decreased due to the abolition of the rice paddy reduction policy. In this study, we used four small bird species as indicators to prove the function and value of abandoned rice field in winter from two aspects. First, we investigated the wintering conditions of the four birds at a total of 474 grasslands from the Tohoku region to the Ryukyu Islands using line censuses combined with call-playback, and clarified their actual use of rice field. Second, we investigated the detailed wintering conditions of the four birds at six abandoned rice field in Ibaraki Prefecture using line censuses combined with call-playback, automatic call-recordings, and camera traps, and measured the vegetation condition at a total of 25 spots, and showed the corresponding relationships.

Free Research Field

保全生態学

Academic Significance and Societal Importance of the Research Achievements

本研究は、現在最も危機的に瀕した生態系である湿性草原環境の生物多様性の保全において、稲作水田の耕作放棄地が高い生態的機能と保全的価値を有することを、絶滅危惧種を含む鳥類を指標として広域的かつ直接的に示した初めての例である。特に越冬環境として評価できることを示したことに特徴がある。本研究によって、稲作水田の耕作放棄地が、湿性草原環境の生物多様性の保全に大いに利用されることが期待できる。