Spatial analysis of flood area and its impact on rice production on vientiane plain

Abstract

We used spatial analysis of flood area to estimate the impact of 2011 floods on rice production in Dong Khuai Village, Xaithany District, Vientiane Prefecture, Laos. We investigated the following: (1) Change of rice paddy area using Global Positioning System (GPS) tracking and information from interviews; (2) variability of flood area estimated by numerical modeling; and (3) land use classification using satellite imagery. Overall, we found that the flooding in 2011 had a significant impact on rice production in Dong Khuai Village. GPS data, flood simulations, and satellite imagery showed that many rain-fed rice cultivation areas decreased as a result of the massive floods. The flooding caused the loss of rice seeds, which prevented villagers from continuing floating rice cultivation. Based on our analysis, we propose conversion of wastelands to floating rice fields, and the creation of a buffer zone based on flood risk information. In addition, we recommend establishment of a sharing system for floating rice seed to reduce the risk of seed loss.