Analysis of irrigation water demand and supply in the Lhasa River valley, Tibet
LI Dan1, LUO Hongying2, LUO Yufeng1, 2*, CUI Yuanlai1, LI Yuqing2, MENG Qiang2
1.State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, Hubei 430072, China; 2.School of Civil and Hydraulic Engineering, Xizang Agriculture and Animal Husbandry College, Nyingchi, Tibet 860000, China
Abstract：Investigations into the balanced relationship between irrigation water demand and supply would provide the theoretical basis for irrigation water management in the period of crop growing and water resources comprehensive development. Taking the lower Lhasa River valley as the study area, the total irrigation water requirement in different typical years was calculated according to the meteorological data from Lhasa and Mozhugongca meteorological station in 1989—2010 and the stable crop(highland barley, winter wheat and oilseed rape)planting area extracted from Landsat remote sensing images in the same period. The balance between the irrigation water demand and supply was analyzed based on the runoff sequence from 1989 to 2010 in Lhasa hydrological station and the irrigation water demand. The major results could be summarized as follows: the planting structure in the Lhasa River valley was dominated by food crops. The planting area increased by about 8% from 1990 to 2010 and there was no significant change in crop planting structure. The increase in crop acreage resulted in a significant increase in irrigation water demand. The irrigation water demand reached 1.6 billion cubic meters in 2010, up 35% over 1990. Highland barley is the crop with the greatest need for irrigation. Seasonal changes in river runoff and irrigation water demand were different. The relationship between irrigation demand and supply from April to June is relatively tight with the proportion of irrigation close to 10% to 20%. The river is in a dry season from December to April of each year. Despite the fact that the irrigation water requirement during the same period was relatively small, the pressure of irrigation water requirement on water resources cannot be ignored. The relationship between water supply and demand in the Lhasa River valley is relatively intense.
李丹, 罗红英, 罗玉峰,*, 崔远来, 李玉庆, 蒙强. 西藏拉萨河谷灌溉供需水分析[J]. 排灌机械工程学报, 2018, 36(10): 1053-1058.
LI Dan, LUO Hongying, LUO Yufeng, *, CUI Yuanlai, LI Yuqing, MENG Qiang. Analysis of irrigation water demand and supply in the Lhasa River valley, Tibet. Journal of Drainage and Irrigation Machinery Engin, 2018, 36(10): 1053-1058.
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