Phosphorus Input into Artificial Water Bodies in Kalmykia from Cattle-Breeding Farms

Resumo

Artificial water bodies in Kalmykia, which is known to have limited water resources, have been constructed for drinking water supply to the population, cattle-breeding, and irrigation. Nowadays, they are heavily polluted by nutrients. The authors’ estimates support the assumption that cattle-breeding (cattle drinking and wastes from cattle-breeding sites) in the drainage basins results in the input of 1–2 t or 20 to 700 g of phosphorus per 1 m² water surface per year in the absence of other pollutants, thus being the main cause of the fact that phosphorus concentration in all examined water bodies is tens of thousands times greater than the maximal allowable concentration for water bodies used for fishery (MAC_f). The share of cattle stock in the total phosphorus input is maximal (80%). Phosphorus load is 1–3 orders of magnitude greater than the allowable and critical values for aquatic ecosystem functioning, creating the conditions for eutrophication and making the water of these reservoirs undrinkable even for cattle.