Ektraction of humic acide from soil

Humic substances (HS) are the most important source of organic carbon in both terrestrial and aquatic environments , and play a key role in nature. They contribute to the growth of plants, are responsible for the structure and physical?chemical properties of soil, and are involved in the majority of surface phenomena that occur in soil . Humic substances can be divided into three components: fulvic acids (FAs), humic acids (HAs) and humin. One of the most important parts of HS is HAs. Rhododendron is a highly celebrated ornamental genus because of its spectacular flowers, species-richness, ease of hybridization and broad geographical range [3]. Approximately 1000 species inhabit a vast geographical range, from the tropics to the polar zone and alphine to sea leval. Rhododendron ponticum L has been documented throughout the Black Sea Region of Turkey.