本文利用黄土高原208个气象台(站)的历年旬降水量与计算的旬潜在蒸发量之比(R/PE),经过10旬滑动平均计算,确定了湿润期(G)及变差系数(C)、播种雨开始期(S)及其标准差(δ)和干旱指数(A),同时还计算了湿润期内出现的干旬(D)、湿旬(W)及其标准差(β、α)。湿润期及其变量的研究,对合理安排农业生产具有重要意义。

In this paper the data on the humid period and its parameters are used to assess the agricultural production of the Loess plateau.The mean humid period (G) and its coefficient of variation (C) and aridity index (A) are related to the cropping system and the risk level of agricultural production.The mean wet (W) and dry (D) spells within the humid period and their standard variations (α,β) are related to the possible drought and water-logging disasters.The above-mentioned parameters can be also used to assess the agricultural climatic environment and the agricultural production potential of the Loess Plateau.