Knowledge achieved on properties of humic acids and their importance in defining the multiple features of soils and plant nutrition, for a long time ago, to the idea of using the low-grade coals (lignite, leonardite) which contain high amounts of humic acids as organo-mineral fertilizers. Currently, in many countries like United States, Japan, China, Israel, Spain, Russia, there are many units which produce humic fertilizers at an industrial level. Taking into consideration the fact that these fertilizers are applied on increasing areas using technologies developed for improving plant nutrition under environmental protection conditions, it is possible to estimate that fertilization with humic fertilizers develops as a new strategy with global features. The production of humic fertilizers with humic acids extracted from lignite is justified because in Romania there are some large coal mining exploitations especially in the Oltenia region, which supply coal suitable for producing such fertilizers. In Romania, which available reserves on lignite a class of liquid fertilizers composed of humic acids in potassium humate form mixed with various mineral salts was developed under the generic name of FERTHUM. In this paper are presented the features of these fertilizers, their fertilizing effects on plant nutrition and soil fertility improvement, as well as the estimation of their usage on large areas in Romanian agriculture.

potassium lignite, humic acids, lignite, liquid Fertilizers

Presentation: oral