Agri-environmental indicators for biodiversity in the rice paddy landscape

Transcription

1 OECD Workshop on Agri-Environmental Indicators Leysin, Switzerland, March 2010 Agri-environmental indicators for biodiversity in the rice paddy landscape David S. SPRAGUE, Shori YAMAMOTO, Tatsuya AMANO National Institute for Agro-Environmental Sciences, Tsukuba, Japan Kenji MATSUMORI National Institute for Rural Engineering, Tsukuba, Japan

2 Rice Paddy Fields of Japan The rice paddy landscape is a habitat mosaic Paddy Landscapes mountainous terrace alluvial fan alluvial plain YATSU (small valley) reclaimed land Rural landscapes differ by region because of differences in agriculture practices and topography.

3 Broad indicators of rural environments Large amounts of statistical data on agriculture collected by the Ministry of Agriculture, Forestry and Fisheries (MAFF). Agricultural statistics can be given environmental interpretations. Little direct information about biodiversity in statistical data. Cropland abandonment Improved rice paddy a. Cropland abandonment rates in the Kanto Region of Japan by farm village units. b. Paddy construction in the Kasumigaura Basin. Sources: A. MAFF Agriculture-Forestry Census 2000, B. MAFF 4th Agricultural Infrastructure Survey.

4 National-scale biodiversity surveys National Survey on the Natural Environment by the Ministry of the Environment (MOE) Nation-wide vegetation maps and animal distribution data. Species sampled on broad spatial scales, focused on hot spots. Animal distribution data not linked to agriculture. Joint MAFF and MOE Rice Paddy Organism Survey Very detailed information on presence/absence of fishes, frogs, and aquatic insects. Focused mainly on improved waterways. Vegetation map: National Survey on the Natural Environment Rice Paddy Organism Survey: Tanbo-no- Ikomono Chosa

5 Designing agri-biodiversity indicators for the rice paddy landscape Two major applications: monitoring and targeting. Habitat indicators are based on a landscape approach. Tsuchiura City 1990 Narita City 1989 Ministry of Land, Infrastructure, and Transport National Land Webmap (

6 Yatsuta Long, narrow, dendritic rice paddies, often in shallow valley bottoms and surrounded by woodland. Small area, but accounts for a large proportion of the rice paddy edge and paddy-woodland interface. a. Percentage of narrow rice paddies by farm village in the Kanto Region. b. Example of GIS analysis to extract narrow rice paddies from rice paddy polygons. Source: Agricultural Spatial Information Research Project, NIAES, 2009.

7 RuLIS: Rural Land Information System Inventory on biodiversity, landscape, and human activities. Hierarchical classification of the agro-ecosystem, supplemented by monitoring sites for data on landscape change and species composition. Common Data Base of National Geography in Japan topography, soil, climate, vegetation each data collated as 1 km grid data Class 1 Class 2 Class 3 Class 4 Class 5 Class 6 Class 7 Class 8 Classification of Agro-ecosystem agro-ecosystem in Japan classified into 60 classes at 6 levels map shows 3rd level classes legend Level 6 classes of the Tone River Basin 64 paddy in mountain foot 66 paddy in alluvial plain 67 upland fields & Yatsu paddy 68 upland fields in urban fringe Database structure of the Rural Land Information System (RULIS) Source: Rice Paddy Biodiversity Research Project, NIAES, 2010.

8 RuLIS: Rural Land Information System Detailed survey data matched to the RuLIS framework to model and map potential habitats. Relative number of fish species within an improved rice paddy system in a lowland plain region of Tochigi Prefecture analyzed within the RuLIS framework. Source: 2008 NIRE Research Project: Habitat potential calculation models for organisms in rice paddy areas.

9 Farmland birds Farmland birds in Japan include many species associated with open water because shallow water is retained in paddy fields during the rice growing season. Similar to trends suggested by European data, some species of farmland birds have been declining in Japan. Many waders and egrets seem to be vulnerable to a wide range of agricultural intensification. The association of habitat variables with the richness and abundance of bird species is highly complex, and varies with type of birds and seasons. Functional biodiversity A research program has started on identifying indicator species among insects beneficial to agriculture. Natural enemies of crop pests, especially arthropod predators and parasitoids.

10 Rural Japan: Traditional and Modern Rice paddy landscapes can support a large range of biodiversity because it is a mosaic of aquatic, woodland, and grassland habitats. Indicators can identify places and species for which agri-environmental measures are most needed or would be most effective. Traditional rice paddy fits the definition of seminatural habitat. Continuing work is needed on: Detailed data linking biodiversity with agricultural practice. Measures of agricultural intensification. Consequences of farmland abandonment. Operationalizing the Japanese concept of the countryside the Satoyama. 第 4 回美しい日本のむら景観コンテスト秋田県東由利町土場沢第 11 回美しい日本のむら景観コンテスト大分県豊後高田市小崎