辽宁省建昌地区春播期水热资源气候特征分析

采用气候倾向率、春旱指数等方法,分析了建昌春播期降水和气温的变化特征。结果表明,近50年（19602009年）建昌春播期热量资源在增加,平均气温趋势升高1.25℃;19902009年较19611980年平均气温升高1.00℃;气温稳定通过≥10℃初日变化稳定;终霜日期趋势提前4 d结束,变化幅度由31 d缩短至19 d,趋于稳定。降水量存在增加趋势,降水量变率过大对春播及苗期生长不利;春旱频率较大影响春季播种;重旱、偏旱年有30年,占60%;近20年（19902009年）重春旱频率较之前略有增加。适宜播种期在4月15-20日

Analysis on Climatic Characteristics of Water and Heat Resources during the Spring Sowing Period in Jianchang of Liaoning Province

By using the method of climate trend rate and spring drought index,the variation features of precipitation and temperature in Jianchang during the spring sowing period were analyzed.As indicated by the results,during the spring sowing period from 1960 to 2009,the heat resources was increasing,the average temperature increased by 1.25 ℃;the annual temperature from 1990 to 2009 rose by 1.0 ℃ over that from 1961 to 1980;temperature stabilized through the change of ≥ 10 ℃ initial day;the final frost date ended 4 days early,and the frost period narrowed from 31 days to 19 days,tending to stabilize.The rainfall amount showed an increasing tendency,large precipitation variability was harmful to the spring sowing and seedling period;the large frequency of spring drought affected the spring sowing;during the late 50 years,there were 30 years with heavy and slight drought,occupying 60%;the frequency of heavy spring drought during late 20 years increased slightly,and it was suitable for growing crops from April 15 to April 20.