Assessment of ecological well-being of the territories of pastures

The pasture management of livestock shows the close correlation between the quality of forage and the quality of animal products. The increase in the content of toxicants in the environment leads to their accumulation in plants. The total content of heavy metals in the diets of cows for lead during the grazing period is 2.2 times higher than that during the winter-stall period. It is established that soil pollution with heavy highly hazardous metals as cadmium (Cd), lead (Pb), zinc (Zn) and moderate hazardous metals (for example copper (Cu)) leads to their increased mobility in the food chain and accumulation in animal products. The aim of the current study was to conduct environmental monitoring of grazing area by a bioassay for the use in rapid assessment of environmental state of the territories for creation of pastures. The bioassay was performed at using of sexually mature aquatic organisms. Bioindicators were freshwater mollusks of the family orb snails (Gastropoda Pulmonata Planorbidae) Planorbarius corneus L. or Planorbis planorbis L. which were fed for 30 days long with leaves of Norway maple (Acer platanoides L.) collected at the beginning of the leaf fall and soaked in the distilled water at a temperature 20-25°C for 3-5 days. At the death of 30% or more of the snails, the absence or cessation of egg laying and termination of development of embryos in the eggs the level of pollution is estimated as high, at the death of less than 30% of snails, cessation of egg laying and termination of development of embryos in the eggs - as medium, at the absence of death, maintenance of egg laying band development of embryos in the eggs - as low. The accuracy of the assessment was justified by chemical analysis on the content of heavy metals Pb, Cd, Zn and Cu which are among the priorities for both the background environmental monitoring as well as for environmental assessment of the territories.