中文摘要：

河南省是我国粮食主产区，研究河南省主粮作物的灌溉需水变化规律可为水分高效管理和节水增粮提供实践参考。基于河南省18个气象站点1958--2013年逐日气象观测资料，根据FAO推荐的Penman—Monteith公式计算参考作物蒸发蒸腾量及冬小麦和夏玉米各生育期需水量，利用时间序列分析法和ArcGIS普通克里金插值法研究需水量时空变化特征，采用通径分析法研究作物需水量的变化成因。结果表明：河南省近56a来年均参考作物蒸发蒸腾量为807．0mrn／a，日均蒸发蒸腾量为2．2mm／d，呈波动减少趋势，其中西北和东南地区参考作物蒸发蒸腾量最大，豫西地区的参考作物蒸发蒸腾量跨度较大。冬小麦和夏玉米的净灌溉需水量分别为350～525mm和243～368mm，灌溉需求指数随经度和纬度的增加而增大，冬小麦生长对灌溉的依赖程度高于夏玉米。影响河南省主粮作物需水量的气象因子主要为气温、水汽压、日照、最高气温和风速。

英文摘要：

Henan Province is a main grain crops producing area in China, and water requirement trends of the main grain crops is an important basis for agriculture water saving and yield increasing. Based on the daily meteorological data from 18 stations in Henan Province during 1958 and 2013, reference crop evapotranspiration （ ETo ） and water requirement of winter wheat and summer maize in growth period were estimated by using FAO Penman- Monteith equation and crop coefficient. Time series analysis was used to analyze temporal distribution characteristics of ETo and water requirement. Kriging of ArcGIS was introduced to draw the maps of ETo and water requirement that could present a clear spatial distribution of that, and the causes of water requirement change were manifested by path analysis method. The research results showed that the value of ETo in Henan Province ranged from 672 mm to 977 mm, and the average values were 807.0 mm per year and 2.2 mm per day, which was decreased in recent 62 years. The maximum ETo appeared in the northwest and southeast of Henan Province, and ETo showed a significant difference around the western area. The water requirement of winter wheat and summer maize were 390 562 mm and 314 -426 mm, respectively. The irrigation requirement of winter wheat and summer maize were 350 - 525 mm and 243 - 368 mm, respectively. The index of irrigation requirement of winter wheat and summer maize were 0. 77 - 0. 90 and 0. 66 - 0. 83, respectively. The main grain crops irrigation requirement index of Henan Province tended to increase with the latitude and longitude, and summermaize had less dependence respectively in sensitively on irrigation than winter wheat. When each meteorological factor was removed analysis, the reliability of the regression equation was estimated by the