腐植酸类肥料是一种多功能的有机、无机复合肥料。实验证明:它具有肥效快,稳而持久的特点,同时具有增产和养地的作用,据已报导的资料来肴,着重于大田作物的试验研究较多,对多年生柑桔果树的试验较少。当前,在“农业学大寨”加速建设大寨县的运动中,认真贯彻执行“以粮为纲,全面发展”的方针,柑桔果树向山区发展,急 Humic acid fertilizer is a multifunctional organic and inorganic compound fertilizer. Experiments show that: It has the characteristics of fast, stable and long-lasting fertilizer, and at the same time has the effect of increasing production and raising land. According to the reported data, there are more experimental studies focusing on field crops and less on perennial citrus fruit trees . At present, in the course of accelerating the construction of Dazhai County in “learning from agriculture”, the principle of “taking grain as the key link and developing in an all-round way” has been conscientiously implemented and citrus fruit trees have developed into mountainous areas.