朝阳地区近56年降水趋势分析

Precipitation Trend Analysis of Chaoyang District in Recent 56 Years

[目的]分析朝阳地区降水量变化趋势,为当地农业经济发展提供气候依据。[方法]假定降水量为连续因子,利用最小二乘法进行一元线性回归拟合。[结果]朝阳地区近56年降水量呈下降趋势,年降水总量减少50 mm,生长季减少60 mm,春季增加10～15 mm,降水量减少的主要时段在7～9月份,2000年以后减少最显著。[结论]朝阳地区春季降水量的增加可缓解春播期的旱情。7～9月是植物需水关键期,这段时间降水量的减少对植物生长和成熟不利。

[ Objective ] The research was aimed to analyze the trend of precipitation in Chaoyang region and provide the climate basis for the local agricultural economy. [ Method ] Under the assumption that precipitation factors were the continuous, simple linear regression was made by adopting least square method. [ Result] The precipitation of Chaoyang region showed a downward trend in recent 56 years. The annual precipitation totally reduced 50 ram, and that in the growing season decreased 60 mm, that in spring increased 10 to 15 ram. The precipitation decreased from July to September. The decrease after 2000 was very significant. [ Conclusion] The precipitation increase in spring could alleviate the drought in the spring sowing period. From July to September is the critical period of water requirement for plants and the rainfall decrease was unfavorable for the growth and maturity of plants.