陕西省不同农业种植区热量资源的变化特征

Variation Characteristics of Thermal Resources in Different Agricultural Planting Area in Shaanxi Province

利用陕西96个气象站1971-2013年气象观测资料,将陕西省分为4个农业种植区,采用线性倾向估计法、累积距平、t-检验和GIS技术等方法对各区及全省范围近43a来热量指标包括平均气温、极端气温、≥0℃和≥10℃界限温度有关指标的变化及分布特征进行分析。结果表明:近43a,陕西全省范围内年、季平均气温均呈显著上升趋势(P<0.05),春季增温最快(0.4℃?10a^(-1)),且各热量资源要素与气温极显著正相关(P<0.01)。关中平原春季平均气温增幅最大,且各区突变时间一致;榆林北部风沙区夏、秋、冬和年平均气温增幅最大,且夏季平均气温突变时间最晚。陕南浅山丘陵区年、季平均气温增幅均最小,且秋、冬季平均气温突变时间最晚。陕西≥0℃和≥10℃初日普遍显著提前,终日变化不显著。≥0℃和≥10℃初日提前幅度最大地区分别为关中平原和榆林北部风沙区。受初日提前和终日推后的共同影响,陕西≥0℃和≥10℃持续日数和积温分别以3.5d?10a^(-1)、2.4d?10a^(-1)、90.3℃?d?10a^(-1)和74.9℃?d?10a^(-1)的倾向率显著增加,其中关中平原区增幅最大。冬季平均气温突变时间最早,为1987年,其它热量资源要素均在20世纪90年代中后期发生突变,突变后≥0℃和≥10℃积温等值线明显西移,关中平原热量资源增加最多且最快,陕北黄土高原变化较小。

The distribution and variation characteristics of the thermal resources including average temperature, extreme temperatures and critical temperature （≥0℃ and ≥ 10℃） indices in Shaanxi province from 1971 to 2013 were analyzed based on the data from 96 meteorological stations by using the methods of linear trend estimation, accumulative anomaly, t-test and GIS technique. The results showed that annual and seasonal average temperature increased significantly in Shaanxi province in recent 43 years （P〈0.05）, and maximum increasing in spring at the rate of 0.4℃·10y^-1. There was significant correlation between average temperature and other thermal resources elements （P〈0.01）.The warming rate of spring average temperature in Guanzhong plain was the largest, and its mutation point was 1997, which was consistent with other regions. Annul and other seasonal average temperature of wind-blown sand area in northern Yuling was the largest increased value, and its abrupt time was the latest in summer. The warming rate of annual and seasonal average was the least, and its abrupt time was the latest in autumn temperature in river valley and hills of southern Shaanxi and winter. The initial day ≥0℃ and ≥10℃ advanced remarkably and the final day showed an insignificantly delaying trend. The biggest advanced of initial day ≥0℃ and ≥10℃ was in Guanzhong plain and wind-blown sand area in northern Yuling, respectively. Influenced by the initial day advancing and the final day delaying, accumulated temperature ≥0℃ and ≥10℃ and their duration were increased significantly by 90.3℃·d·10y^-1,74.9 ℃·d·10y^-1,3.5d·10y^-1 and 2.4d·10y^-1, respectively, especially in Guanzhong plain. The winter average temperature mutation appeared in 1987 and other thermal resources elements occurred abruptly change in the middle and late 1990s. The contours of accumulated temperature ≥0℃ and ≥10℃ remarkably moved westward after 1997. After the abruption, the change ranges of accumulated temperature ≥0℃ and ≥10℃ were the most significantly in Guanzhong plain but the least in Shanbei Loess Plateau.