一、引言干旱风在淮北地区一般称为“火风”。这是在空气相对湿度很低、温度又高,并伴随着一定风速条件下所出现的一种大气干旱现象。人们往往把大气干旱和干旱风混为一谈,如B.B.西湟里席柯夫(Синелыщикв)在他的著作中就将这两个名词看成是同一个含义了。事实上,干旱风不应该包合那种空气相对湿度很低、温度高而风速很小的大气干旱在内。ф.ф.达维达雅(Давитая)和国内有关文献中也提及这一点。干旱风对作物的危害,不仅是严重干旱,而且是高温。这一点,Н.А.马克西莫夫(Максимов)在他的著作中早已指出。因此,从干旱风的实貭而言,与其说是干旱风,毋宁说是“干热风”更确切些。

The drought-inducing winds in the area under consideration are analyed according to observation data. Their injuries to winter wheat are brought out by eliminating the effect of soil moisture, and a formula is obtained for calculating drought-inducing wind index, K=(C/C₀)(T≥30)/(R≤30), where C is 13 hr. (or 14 hr.) wind velocity in m.sec.^-1;C₀ critical wind velocity(=3 m sec.^-1);T, 13 hr. (or 14 hr.) temperature in °C; R, relative humidity in %. The day is free of drought-inducing wind, if K<1. With K=1一2, it may be specified as a day with light drought-inducing wind;with K=2一5, a day with moderate drought-inducing wind; and with K>5, a day with intense drought-inducing wind.