Pesticides are still an important group of substances involved in surface water pollution. Their increased occurrence in watercourses in the agricultural landscape is mainly linked to rainfall-runoff conditions, types of cultivated crops, and methods of agricultural management. In order to capture these factors, passive sampling techniques were chosen for the assessment of the load of these substances in selected catchments of water supply reservoirs in the administration of Povodí Moravy State Enterprise. These techniques consist of continuous exposure for several weeks with gradual (integrative) capture of pollution on suitable sorbents. The POCIS (polar organic chemical integrative samplers) were chosen in this work – widely used samplers suitable for capturing polar organic substances. They were applied in eight consecutive sampling campaigns to cover the entire growing season. The aim was to assess the spatio-temporal dynamics (in monthly steps) of selected pesticides and their metabolites into five water supply reservoirs. Due to the scope of the obtained data, this article is focused on the presentation of the results of tributaries into water supply reservoirs Vír I, Opatovice, and Ludkovice, which were monitored in 2021. When the sampling rate Rs was published, it was possible to recalculate the pollution captured by the passive sampler to average concentration during exposure. The results showed which tributaries into the reservoirs were loaded by these hazardous substances in the individual periods of the growing season. The results can be compared with the type of crops grown in a given year.
Most of the reservoirs in the Czech Republic have been built as multifunctional reservoirs, with the basic functions being storage and protection. The way the catchment area upstream of a reservoir is used has a significant impact on water quality. Pollution sources can be divided into point, area, and diffuse sources. Being continuous or recurrent, point pollution is not significantly influenced by meteorological factors and it is linked to narrowly delimited areas such as settlements, wastewater treatment plants (WWTPs), industrial plants, agricultural facilities, etc. Area pollution is difficult to observe as it is irregular and depends on meteorological, soil, morphological, and vegetation characteristics . The category of diffuse sources usually includes small diffuse point sources of pollution, namely municipal, agricultural, industrial, as well as traffic pollution, leachates from landfills, etc.
The article deals with space-time dynamic of non-polar and polar compounds load into the drinking water reservoir Švihov in Želivka river basin during the whole vegetation season by passive sampling techniques. The monitoring on the nine tributaries of the Švihov water reservoir and on the raw water inlet to the Želivka drinking water treatment plant took place for eight months from April to November 2018.
The contribution presents model tests of sorption efficiency and elimination of organic substances, especially pesticides from five different exposed granular activated carbon (GAC). Results can contribute to the understanding of suitable filter lines for the realized investment project GAC filtration.
The use of automatic samplers for detailed monitoring of substance concentrations and balance is nowadays an important part of special monitoring of surface waters. The average results of routine monitoring (consisting of point samples) are often underestimated over the real situation.
The answer to the reaction SOVAK CR to the article Unnecessary hysteria surrounding the use of glyphosate
As a supporter of substantive discussions, I would like to submit one more clarification as a reaction to response of Ing. Ondřej Beneš, Ph.D., MBA, LL.M., SOVAK CR representative.
SOVAK CR has been involved and active in the coordination group and subgroup to protect water for the preparation and implementation of the National Action Plan to reduce the use of pesticides (NAP), which sets out a series of measures and tasks for individual ministries and other bodies.
Water quality in drinking water reservoir Švihov on Želivka river and its river basin, with focus on specific organic compounds
River basin of the largest drinking water reservoir Švihov on the Želivka River is distinctly anthropogenically affected both by direct human activities and also by the agriculture. The quality of the surface water is endangered in long-term period mainly by the eutrophication, pesticides pollution and erosion.