Temporal and Spatial Trends of Spring Maize Irrigation Water Requirement in Northeast China in Recent 60 Years

摘要

In this paper, the daily meteorological data of 78 stations in Northeast China from 1958 to 2017 were used to calculate the evapotranspiration and water requirement during the growth period of spring maize. Combined with M-K trend test and GIS spatial analysis technology, the spatial and temporal trends of irrigation water demand during the growth period of spring maize in the northeastern region were analyzed, and the water demand of spring maize growth period in Northeast China was discussed to provide a theoretical basis for ensuring food production in the main maize producing areas. The results show: in terms of time, the average annual irrigation water requirement during the whole growth period ranges from -237.7 to 346.9 mm, and 92% of the sites irrigation water requirement in the study area is greater than 0. In the milky ripening to maturation stage, the water requirement for irrigation is high and the situation is increasing. From sowing to emergence period, 96% of the sites have a downward trend. In space, there is a significant regional difference in the distribution of irrigation water equirement, and the overall situation is basically reduced from east to west. With the growth of spring maize, the water shortage in western Jilin, northwestern Liaoning and western Heilongjiang has also increased.