Mase paddy flux site
Organization
Agro-Meteorology Division, National Institute for Agro-Environmental Sciences
Research Theme
- Establishment of carbon cycle researches and flux measurement methods on paddy fields in North-East Asia.
- Development of an ecosystem model and remote-sensing techniques for paddy fields.
Site Outline
Mase paddy flux site (36° 03′ 14.3″ N, 140° 01′ 36.9″ E, 11m above sea level) is located in southwestern part of Tsukuba City, Ibaraki Prefecture, Japan. Annual mean temperature is 13.2℃, and annual precipitation is 1197mm (Aerological Observatory of Japan Meteorological Agency, located 9 km east of Mase paddy flux site). Mase paddy flux site is situated in a flat paddy area (200 ha in total, some plots are abandoned), which is surrounded by a bank of the Kokai river (about 200m to the southwest of the flux tower) and a terrace (20m in height, about 800m to the northeast of the flux tower). Prevailing wind direction is between east and south in summer and northwest in winter. Fetch is >500m except for southwest. The soil is a clay loam (loamy, siliceous, mesic Typic Endaqueps).
The plot with the flux tower (0.54ha) and its surrounding plots are managed by local farmers as a single-rice cropping paddy field with customary practices in this area. Rice ( Oryza sativa subsp. japonica, caltivar “Koshihikari”) is transplanted in early May and harvested in early or mid-September. The maximum canopy height is about 1.1m and the maximum leaf area index is about 6. Heading of rice is observed in late July or early August. Mineral fertilizer is applied before transplanting and around heading of rice. Organic fertilizer (compost) is also used rarely as basal fertilizer. The paddy fields are flooded from late April to mid-August except for a mid-season drainage period, which lasts for 10 days or 2 weeks in July. The average annual grain yield from 2002 to 2009 is 5.2 t ha-1. At harvest, only grain and panicle are removed from the field, and remaining parts of rice (straw, stubbles and roots) are plowed into soil after harvest. The paddy fields are plowed a few times in the fallow season and kept almost without plants. In some years, ratoon regrowth is observed from the hargest to the first plowing.
Contact
- Address : 3-1-3 Kannondai, Tsukuba, Ibaraki, 305-8604, Japan
- Name : Keisuke Ono
- Phone : 029-838-8239
- Fax :
- E-mail : onok@affrc.go.jp
WWW site URL
English : http://ecomdb.niaes.affrc.go.jp/show_site_info.php?site_id=1121