云南蒙自坝子主要作物需水量及灌溉需水量研究

根据蒙自坝子中部蒙自气象站1980—2010年逐月气象资料和相应的作物数据及CROPWAT软件，计算了蒙自坝子近31年来的作物需水量和灌溉用水量，通过排频，确定了不同作物在相应保证率下的灌溉用水量。研究结果表明，水稻、玉米、马铃薯、烤烟、花生等大春作物的多年平均作物需水量分别为696．2、427．7、517．8、414．0和469．0mm，作物需水量离差系数较小。大春作物生育期有效降雨量较多，故灌溉需水量很少，但水稻因为泡田用水、秧田用水、生长期渗漏等，导致灌溉用水量很大，成为灌溉需水量最大的作物；小春作物蚕豆、小麦、油菜的多年平均作物需水量分别为394．8、412．5、476．2mm。因为生育期内有效降雨量相对较少，小春作物灌溉需水量很大；甘蔗、蔬菜为全年种植（生长）作物，作物需水量分别为1308．3和1186．9mm，灌溉需水量分别为675．2和523．51／11／1，成为仅次于水稻的第2和第3位灌溉需水量最大的作物。该研究为蒙自坝子灌溉制度制定、作物种植结构调整提供了理论依据。

Research on Main Crops Water Requirement and Irrigation Requirement in Mengzi Basin of Yunnan

According to monthly weather data and the corresponding crop data as well as CROPWAT software of Mengzi Meteorological Station in central Mengzi Basin,crop water requirements and irrigation water use are calculated.By frequency analysis,irrigation water requirement was get for different guaranteed rates.The results show that: average crop water requirements of rice,corn,potatoes,tobacco and groundnuts were 696.2,427.7,517.8,414.0 and 469.0 mm,respectively,crop water dispersion coefficient was small,period effective rainfall during crop growth was much,so irrigation water demand was smaller,but rice needed much irrigation water to meet the requirement of soaking field and leakage.While the multi-year average crop water requirements were 394.8,412.5,476.2 mm,respectively,for small spring crops of broad beans,wheat,rape.Because the effective rainfall for these crops during growth period was relative less,crop irrigation water requirements for small spring crop was much.Sugarcane and vegetables were plants around the year,so the crop water requirement was high,which reached 1 308.3 and 1 186.9 mm,respectively,and irrigation water requirements were the second and third largest.The study provided theoretical basis for crops' structural adjustment and irrigation program formulation of Mengzi Basin.