1968―2018年民勤地区参考作物需水量的年际变化特征及相关气象影响因子研究

Study on Interannual Variation Characteristics of Reference Crop Water Requirement and Related Meteorological Influencing Factors in Minqin Area from 1968 to 2018

【目的】研究民勤地区作物需水量的主要影响因子。【方法】基于民勤地区1968―2018年气象数据,利用Penman-Monteith公式计算了不同时间尺度的平均参考作物需水量ET0,分析ET0变化趋势,并与气象因子变化趋势进行相关性拟合。【结果】1968―2018年民勤地区年平均参考作物需水量呈波动上升趋势,最低值为1968年的3.15mm/d,最高值为2013年的3.72 mm/d,且参考作物需水量的上升趋势是从2003年开始最为明显;参考作物需水量与年平均最高气温、年平均最低气温、年平均气温、年平均相对湿度、年平均日照时间以及年平均风速的相关性比较显著,与降雨量和净辐射相关关系不显著。【结论】民勤地区的干旱状况目前处于平稳期,年平均最高气温和年平均相对湿度是导致民勤地区参考作物需水量年际变化的最主要的气象因子。

【Objective】This paper aims to study the main influencing factors of crop water requirement in Minqin area.【Method】Based on the meteorological data of Minqin area from 1968 to 2018, the average reference crop water requirement ET0 was calculated by Penman-Monteith formula at different time scales, and the change trend of ET0 was analyzed and correlated with the change trend of meteorological factors.【Result】The annual average reference crop water requirement in Minqin area has shown a fluctuating upward trend during 1968 to 2018, with the lowest value being 3.15 mm/d in 1968 and the highest value being 3.72 mm/d in 2013, and the rising trend of reference crop water requirement has been most obvious since 2003;the reference crop water requirement and the annual average maximum temperature, annual average minimum temperature, etc. The correlation between annual average temperature, annual average relative humidity, annual average sunshine hours and annual average wind speed was significant, but not significant with rainfall and net radiation.【Conclusion】The annual average maximum temperature and annual average relative humidity are the main meteorological factors leading to the interannual variation of reference crop water demand in Minqin area. The drought situation in Minqin area is in a stable period at present, which can provide reference for the formulation of irrigation system and the prediction of future water consumption.