Institute for Agro-Environmental Sciences, NARO

Agrobiodiversity Assessment Unit

Agriculture is a human activity to produce food and life materials utilizing matter cycles, which are mediated by wild organisms as well as crop/domestic animals. Therefore, agricultural production depends on biological diversity and the benefits people obtain in various ways from ecosystems, referred to as ecosystem services. Recently, the changes in agricultural activities through the variation of socio-economic status, such as the reduction of food self-sufficiency ratio and human population decline, in Japan have caused biodiversity losses and ecosystem service degradation, and thus destabilization of agricultural production are of concern.

We investigate diversity of organisms including birds, spiders, insects, plants and earthworms in/around farmlands, and attempt to reveal factors affecting biodiversity and ecosystem services in agricultural landscapes, focusing on agricultural practices, such as organic farming, and landuse changes, such as the increase in area of abandoned farmlands. We finally aim to propose farmland management practices and proper landuse which are necessary to maintain/increase biodiversity and ecosystem services and to achieve sustainable agricultural production.


Unit Leader

Hiroaki IKEDA
Research Topics : Plant ecology and conservation

Unit Members

Research Topics
Satoshi KANEDA Principal Researcher Earthworm diversity and function
Yuki BABA Researcher Arthropod ecology and diversity
Naoki KATAYAMA Researcher Bird ecology and conservation
Koichi TANAKA Re-employed Staff Arthropod ecology and diversity

Research Publications

  • Baba YG, Tanaka K (2016) Factors affecting abundance and species composition of generalist predators (Tetragnatha spiders) in agricultural ditches adjacent to rice paddy fields. Biological Control 103: 147-153.
  • Kaneda S, Ohkubo S, Wagai R, Yagasaki Y (2016) Soil temperature and moisture-based estimation of rates of soil aggregate formation by the endogeic earthworm Eisenia japonica (Michaelsen, 1892). Biology and Fertirlty of Soils 52: 789-797.
  • Katayama N, Baba YG, Kusumoto Y, Tanaka K. (2015) A review of post-war changes in rice farming and biodiversity in Japan. Agricultural Systems 132: 73-84.


  • Baba YG, Tanaka K 2016 Environmentally friendly farming and multi-scale environmental factors influence generalist predator community in rice paddy ecosystems of Japan. In: Yagi K, Kuo GC (eds) The Challenges of Agro-Environmental Research in Monsson Asia, NIAES Series No.6, pp.171-179.
  • Tanaka K. 2016. Functional biodiversity indicators and their evaluation methods in Japanese farmlands. In: Yagi K, Kuo GC. (eds) The Challenges of Agro-Environmental Research in Monsson Asia, NIAES Series No.6, pp.157-168.