国立研究開発法人 国際農林水産業研究センター | JIRCAS

Regional Consequences of Seawater Intrusion on Rice Productivity and Land Use in Coastal Area of the Mekong River Delta

JARQ : Japan Agricultural Research Quarterly
ISSN
00213551
書誌レコードID(総合目録DB)
AA0068709X
本文フルテキスト

This study investigates rice productivity in the coastal area of the Mekong River Delta, Vietnam focusing on relationships with the influences of seawater intrusion and recent changes in the land use at regional scale. We examined the statistical data on rice production at 30 districts of 4 provinces in the coastal area for the years 2003-2005, together with the average salinity concentration observed at 48 points in canals and rivers during the dry season. As an index of the extent of seawater intrusion to be compared with rice statistical data in each district, average salinity of each district was derived by using spatial interpolation from the data in the observation points. It was shown that seawater intrusion was the major factor leading to regional differences in rice cropping systems and land use patterns in the region. Rice cropping intensities, which is defined as the ratio of planted area to district area, decreased with increasing salinity level in canal water, but rice yields averaged over the district are independent of the salinity level. To avoid salinity stress to rice growth, rice cultivation in the coastal area is mainly undertaken during the period when seawater intrusion is weakened by the seasonal decrease in salinity in the rainy season. Specifically, in districts with high salinity, the salinity-free duration required for rice cultivation is short. There, rice cropping intensities are potentially limited by the salinity. In addition, recently, the area of paddy fields in the coastal area has been decreased through land use conversion to aquaculture, especially shrimp farms. Intensity of aquaculture, which requires brackish water, was also limited by seawater intrusion. Thus, rice production in the coastal area of the Mekong Delta was limited by the interrelationship between seawater intrusion and land-use diversification.

刊行年月2008-10-01
作成者KOTERA AkihikoSAKAMOTO ToshihiroNGUYEN Duy KhangYOKOZAWA Masayuki
著者キーワード

cropping pattern

rice yield

salinity

公開者Japan International Research Center for Agricultural Sciences
データ作成日2008-10-01
国立情報学研究所メタデータ主題語彙集(資源タイプ)Journal Article
42
4
開始ページ267
終了ページ274
DOI10.6090/jarq.42.267
権利Japan International Research Center for Agricultural Sciences
言語eng