Effects Of Climate Spatialchange On Maize(Zea Mays L.) Production In Heilongjiang Province Of 44 Years

Climate change has a direct and profound influence on crop production. This article analyzes the temporal and spatial variation and trend of heat, light, precipitation and other main meteorological factors by using the data based on 26 weather stations in Heilongjiang Province throughout 1971-2014. And it takes maize-a crop with the largest cultivated area in Heilongjiang Province as an example, demonstrating the influence of climate change on maize yield per unit, planting area, varieties distribution and growth duration. The main results are gi ven in the paragraphs below.(1)Temporal and spatial variation and trend of active accumulated temperature in Heilongjiang Province.From 1971 to 2014, we can see an increase in annual average active accumulated temperature which is greater than or equal to 10℃,and that with increasing 251℃ averagely over the past 44 years. Active accumulated temperatures of Qiqihar(the first accumulatedtemperature zone), Mudanjiang(the second accumulated temperature zone), Shangzhi(the third accumulated zone) and Sunwu(the forth accumulated temperature zone)have increased over 350℃ over the past 44 years, suggesting a significant warming. Meanwhile,accumulated temperatures of Mohe, Tahe in the sixth accumulated temperature zone and Mingshui in the third accumulated temperature zone have only increased less than 60℃ over the past, which are not very significant. And active accumulated temperatures of other weather stations have an upward trend range from 150 ℃ to 300℃ over the past 44 years. As a result, present division standard is not appropriate for practical production any more, we need to redefine the division standard of accumulated temperature zone in Heilongjiang Province.(2)Temporal and spatial variation and trend of sunshine hours in Heilongjiang Province.We can only see a slight increase in three stations of 26 weather stations in Heilongjiang Province, which is Tonghe(the second accumulated temperature zone), Tieli(the third accumulated temperature zone) and Mohe(the sixth accumulated temperature zone), their total increasing sunshine hours are less than 40 hours. There is an downward trend in other 23 stations throughout the past 44 years. The sunshine hours of Tailai(the first accumulated temperature zone), Jixi(the second accumulated temperature zone), Mingshui(the third accumulated temperature zone) and Suifenhe(the fourth accumulated temperature zone) have decreased more than 200 hours in the 44 years, and the declining sunshine hours of other 19 stations are between 0-200 hours.(3)Temporal and spatial variation and trend of precipitation in Heilongjiang Province.In these 26 weather stations, we can see an increase of precipitation in 14 stations throughout the period from 1971 to 2014: Tailai and Qiqihar(the first accumulated temperature zone), Jixi, Mudanjiang, Jiamusi and Yilan(the second accumulated temperature zone), Hulin, Mingshui and Keshan( the third accumulated temperature zone), Beian( the fourth accumulated temperature zone), Huma and Sunwu(the fifth accumulated temperature zone), Mohe and Tahe(the sixth accumulated temperature zone).Their annual precipitation increases in the range of 0-110 mm, among which Tailai and Qiqihar,the western part of Heilongjiang Province, rises from <400mm to >400mm and these two Semiarid areashave turned into subhumid areas. The precipitation reduction of remaining 12 meteorological stations ranged from 0to 110 mm at different degree in the past 44 years.(4)The increase of active accumulated temperature in Heilongjiang Province lead to a significant dec ize.rease in frequency and strength of chilling damage-the main reason of yield reduction of ma(5)Different meteorological factors have different effects on yield per unit area of maize in Heilongjiang Province. The influence of temperature on the yield of maize is mor e significant than that of sunshine and precipitation.(6) Climate change in Heilongjiang Province has an impact on maize varieties distribution. Although the climate saw a warming trend, we still need to pay attention to the choice of maize varieties. Afforestation of middle maturing and late maturing varieties is not recommended, that is to say, early and late maturing varieties should be planted in an appropriate proportion.