EN
This paper presents a study on the concentration of dissolved organic carbon (DOC) and humic substances (HS) in the waters of two different small ponds located in agricultural environments. DOC and HS content is high in the water of pond R adjacent to cultivated fields (DOC 42.0 mg/1, HS 34.2 mg/1) and in pond H surrounded by a wide belt of meadow and settled by macrophytes (DOC 48.0 mg/1, HS 37.2 mg/1). The total amounts of cations and cations bounded with humic substances dissolved in water of these two ponds have been analyzed. These studies indicate that small field ponds are a good biogeochemical barrier controlling organic compound migration with water from arable fields into water reservoirs.