选取鄂北岗地及其附近8 个气象站点1960 年- 2013 年逐日的气象观测数据, 采用FAO 推荐的Penman2 M ontecito 模型计算该地区参考作物蒸散量和干湿指数, 在此基础上利用Mann2Kendall 突变检验、M or let 小波分析 等方法分析了干湿指数的变化趋势和总体特征。结果显示: 1960 年- 2013 年鄂北岗地干湿指数呈波动上升趋势, 其变化速率为01 038/ ( 10a) , 干湿状况有所改善; 夏季干湿指数最大, 春秋次之, 冬季干湿指数最小; 1980 年- 1981 年期间, 干湿指数发生了一次由低到高的突变; 干湿指数变化过程主要存在3~ 6 a、8~ 15 a 和17~ 25 a 等3 类尺度 的周期变化规律, 而13 a 左右的周期变化是干湿变化的主周期; 干湿指数与相对湿度和降水量成正相关, 与气温、 风速、日照时间成负相关, 而降水量是导致干湿指数变化的主导因素。

Based on the daily meteor olog ical data of eig ht w eather stat ions in H illock Ar ea o f nor thern H ubei fr om 1960 to 2013, the v alues of refer ence cro p evapot ranspiratio n and dr y2w et index w ere calculated using t he Penman2Montecito equatio n r ecom2 mended by the FAO, and the v ariat ion tendency and g ener al char act eristics o f dry2wet index w ere analyzed by the methods of Mann2Kendall test and Morlet wavelets analysis. The r esults indicated that ( 1) the dry2wet index has incr eased slow ly with a rate of 01 038/ 10a from 1960 to 2013, and the dry2w et condition has been improved to some extent; ( 2) the dry2wet index is the highest in sum2 mer, fo llowed by spring and autumn, and the low est in winter; ( 3) the dry2wet index has an abrupt chang e from 1980 to 1981; ( 4) the dry2w et index has three periodicities of 3~ 6 years, 8~ 15 years, and 17~ 25 years, and the primary perio dicity is 13 year s; and ( 5) the dr y2w et index has posit ive cor relation w ith relativ e humidity and precipitat ion, and negative cor relation w ith t emperat ur e, w ind speed, and sunshine time, and pr ecipitation is the dominant fact or t o cause the var iatio n o f dr y2w et index .

国家自然科学基金项目( 41101544) ; 湖北省高等学校优秀中青年创新团队项目( T 201314)