 |
WELCOME to STATE of the ENVIRONMENT IN UKRAINE |
 |
 |
 |
 |
 |
LAND RESOURCES AND SOILSContent of toxic agents in the soil and water reservoirs used in agriculture, and in agricultural cropsState research and reconnoitering stations for chemicalization of agriculture under the Ministry of the Agroindustrial Complex of Ukraine in 1998 conducted an agrochemical survey of soils to determine the content of contaminating substances. A ban on the utilization of persistent highly-toxic pesticides, especially those belonging to the chlorine organic combinations group, resulted not only in a reduction of frequency of detection of their traces in the samples by several per cent, but also in a lowering of their absolute concentrations to levels not exceeding the permissible norms for the soil and agricultural crops. For the sake of comparison it is worth mentioning that in the period
of the most extensive application of pesticides (1986-1987), the frequency
of detection in samples was as high as 42-48% in the soil and 45-50% in
the agricultural crops, which exceeded the permissible level by 4.4% and
7.5%, respectively. Most frequently detected in the soil were the following
pesticides:
Analysis of the agricultural crops contamination with pesticides was based on data taken from about 200,000 samples of 18 crops. It showed that in the agricultural crops of the crop years of 1980-1990 the following seven agents were most frequently traced (PHK - 60%, lenacil - 64%, atrazin - 63%, simazin - 55%, alirox - 54%, sitrin - 52%, THAN - 51%). By plants, traces of pesticides were most often detected in table beets (50.2%), corn (50%), barley, peas, oats (45%). As for feed plants and crops, the concentrations of pesticides most frequently exceeded the maximum permissible level in the samples of the following vegetables and crops: carrot (36.4%), table beet (26.0%), potato (12.7%); as for the foodstuffs: grain crops (25.3%), carrot (27.7%), potato (12.5%). In the recent years one can also note a considerable decline in the level of vegetable contamination with nitrates. Thus, in 1985-1987 the number of samples of the major vegetables (potato, cabbage, carrot, cucumber, table beet) with a level of contamination above the maximum permissible ran as high as 17-23% on average as compared to similar figures for 1997-1998, which show a dramatic drop to 1-2% (see Table 3.27.) State supervision has been also extended to the contamination of various types of water reservoirs with nitrates. In 1998 about 5,000 samples of water were taken and analyzed. Unlike the dynamics of plant contamination with nitrates, its concentration in water reservoirs is a little bit different. During the whole period of monitoring the nitrate concentration in the water was more or less stable. The highest level of concentration, as in the previous years, was detected in water coming from cattle farms (9,694 mg/l). A high level of pollution was found in water from enclosed sources (wells and flowing wells). The water samples taken from wells showed an average nitrate concentration of 104.2 mg/l, which is more than two times above the permissible level. About 48% of water samples exceeded this level. Running water systems (rivers, lakes, ponds) produced better samples where the concentration of nitrates accounted for 12.8 mg/liter on average. No more than 5% of samples showed a concentration of nitrates exceeding permissible levels. In 1998, 16% of 5,000 samples taken from open and enclosed water reservoirs displayed a nitrate concentration above the permissible level. In some regions (Luganska, Mykolaivska, Ternopilska, Cherkasska) this indicator was as high as 29-38%. According to monitoring results the content of heavy metals in agricultural lands in the majority of the Ukrainian regions does not exceed the maximum level of contamination, and only in the suburban areas of Zaporizka, Luganska, Donetska, Kharkivska and some other regions does the arable land show an increased concentration of lead, cadmium, nickel, manganese and other elements. In some cases concentrations exceed the maximum level by 2 to 5 times. It must be mentioned that in order to conduct comprehensive monitoring of the agroecological situation of the soil and the quality of agricultural products, it is necessary to considerably improve logistics support of the activities of the research and reconnoitering stations for chemicalization of agriculture in the regions.
|
