普洱水稻需水规律及灌溉定额研究

Study on Water Demand Law and Irrigation Quota for Pu'er Rice

以普洱市永庆试验点水稻为例,开展水稻需水规律及灌溉定额试验研究,以试验结果及永庆1970~2014年气象数据为基础,分析得到了不同水文年普洱水稻需水量与灌溉定额。结果表明,普洱地区日均ET0从返青期开始减小,抽穗开花期最小,后不断增加,与日照时数呈极显著正相关关系(p=0.001),与相对湿度呈显著负相关关系(p=0.014)。水稻日均需水量变化和ET0变化趋势一致,也是在抽穗开花期最小,返青期最大,这和其他地区水稻需水规律有较大差异。全生育期水稻作物系数为1.11。丰水年、平水年和枯水年需水量分别为533.8mm、574.2mm、601.1mm,受降雨量普遍偏高的影响,不同水文年水稻灌溉定额偏小,丰水年、平水年和枯水年灌溉定额分别为247.2mm、296.6mm和316.2mm。

Taking a case of the rice at the Yongqing experimental site in Pu ＇er City, a study was made on the water demand for rice and irrigation quota. Based on the experimental results and the meteorological data at the Yangqing Station during 1970-2014, the water demand for rice and irrigation quota in the various hydrological years were obtained. It was found that the average of ET0 in Pu＇er region start decreasing from rice returning green stage, which reach minimum in heading and flowering period, and then continually increase. There is a significant positive correlation between daily ET0 and sunshine hours（p=0.001）, and negatively correlated with relative humidity（p=0.014）. The average daily ETc of rice and ET0 were in the same trend, but also minimum in the flowering stage, and maximum in returning green stage, which is a big difference from other areas. The crop coefficient of rice in whole growth period is 1.11. The ETc in wet year, normal year and dry year are 548.2 mm, 589.8 mm and606.7 mm respectively, and the irrigation quota of rice in wet year, normal year and dry year are 282.5 mm, 350.5 mm and 378.8 mm respectively.