Impacts of Climate Change on Rice Yield, Case: Nam Xong
Khadka, Nishan (2016)
Metropolia Ammattikorkeakoulu
2016
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Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:amk-201605229114
https://urn.fi/URN:NBN:fi:amk-201605229114
Tiivistelmä
Most of the farmers in Lao PDR cultivate rice as the source of living. Most of the area used for rice cultivation is rainfed rice. The agriculture of a vast population in Nam Xong River Basin is dependent on monsoons where rice is grown between May and November. The most important parameters to determine the yield variation in the region is the climate and soil contrast.
Nam Xong River Basin is located in the Vientiane province. It is divided into mountainous upper Nam Xong, valleys in the middle and flat plains in lower plains. Rainfed rice cultivation is largely located in the valleys (Vangvieng) while irrigated agriculture can be found in lower Nam Xong. The variation of rice yields in the Nam Xong water shed is mostly due to the variation in rainfall.
IWRM model is hydrological model based on grid representation of the modelled catchment. The precipitation and temperature were taken as input in IWRM model. Soil and water parameters were calibrated in the model to get output yield closer to observed yield. After calibration, climate change scenarios were taken as input for yield projection.
Vangvieng possesses high rice yield among all other agricultural study areas. It receives high and sufficient rainfall which has a beneficial effect on rice cultivation whereas lower Nam Xong receives less rainfall. This paper examines the rainfed rice cultivation practice in the Nam Xong basin. It focuses on the climate change and its significant impact on rice yields. Particularly, the climate induced precipitation change is discussed in this paper.
Based on the findings, it was discovered that there is a moderate impact of climate change on rice yields. Under climate change scenarios, the rainfall received by Vangvieng is excessive which is the main cause for reducing yield. The impact caused by the precipitation change is approximately 1.5% loss in rice yields. Social and economic factors are not considered. Due to the lack of reliable irrigation data, the research is only limited to the rainfed rice cultivation.
Nam Xong River Basin is located in the Vientiane province. It is divided into mountainous upper Nam Xong, valleys in the middle and flat plains in lower plains. Rainfed rice cultivation is largely located in the valleys (Vangvieng) while irrigated agriculture can be found in lower Nam Xong. The variation of rice yields in the Nam Xong water shed is mostly due to the variation in rainfall.
IWRM model is hydrological model based on grid representation of the modelled catchment. The precipitation and temperature were taken as input in IWRM model. Soil and water parameters were calibrated in the model to get output yield closer to observed yield. After calibration, climate change scenarios were taken as input for yield projection.
Vangvieng possesses high rice yield among all other agricultural study areas. It receives high and sufficient rainfall which has a beneficial effect on rice cultivation whereas lower Nam Xong receives less rainfall. This paper examines the rainfed rice cultivation practice in the Nam Xong basin. It focuses on the climate change and its significant impact on rice yields. Particularly, the climate induced precipitation change is discussed in this paper.
Based on the findings, it was discovered that there is a moderate impact of climate change on rice yields. Under climate change scenarios, the rainfall received by Vangvieng is excessive which is the main cause for reducing yield. The impact caused by the precipitation change is approximately 1.5% loss in rice yields. Social and economic factors are not considered. Due to the lack of reliable irrigation data, the research is only limited to the rainfed rice cultivation.