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AbstractDiffuse pollution by pesticides, particularly herbicides, has been recognized in the UK for several years. Atrazine, Simazine, Mecoprop, Dimethoate and, more recently, Isoproturon and Chlortoluron have been found frequently in surface waters at concentrations up to 0.5 μg/l, with a maximum of 11.5 μg/l. Pesticides are detected less frequently in groundwaters, at concentrations generally lower than 0.1 μg/l. Atrazine is found most frequently. Concentrations in untreated surface and ground‐waters have generally been below the maxima recommended for drinking water by the Department of the Environment (DoE). Concentrations in treated drinking water have not exceeded the DoE recommended maximum concentrations, but measures are being taken to reduce concentrations to below 0.1 μg/l.

Årsliste 2008 ; In 2006 and November 2007, the Coordination Centre for Effects (CCE) under the UNECE LRTAP Convention issued calls for data on results from dynamic models to soils and surface waters given specified future scenarios of sulphur (S) and nitrogen (N) deposition. Submitted data from Norway is summarized here. 1007 lakes sampled in 1995 were modelled using the MAGIC model. The results were then matched to 2304 grid squares in the critical load grid for Norway. The past, present and future deposition (CLE=current legislation, i.e. Gothenburg protocol, and MFR=maximum feasible reduction) were specified by the CCE for each EMEP grid square. The results showed that the increasing trend in acid neutralizing capacity (ANC) in surface waters observed since 1990 will continue slightly through 2020. Many lakes in southernmost Norway will continue to be acidified (critical load exceeded) unless deposition of S and N is reduced substantially below requirements of the Gothenburg protocol. Under the MFR scenario, ANC can increase in most lakes throughout the country. Many lakes in Finnmark in northernmost Norway will experience reacidification due to projected increases in S and N deposition. ; Statens Forurensningstilsyn

Årsliste 2005 ; Target load is a logical extension of the critical load concept and incorporates the time delays in the chemical recovery from acidification. Calculations based on data from the Norwegian monitoring lakes and the dynamic acidification model MAGIC show that the increased ANC in Norwegian surface waters observed since 1990 can be expected to continue to increase to 2010 if the planned emission reductions of the Gothenburg protocol and other legislation are implemented. With no further reductions after 2010 the ANC will still increase slightly, but very slowly due to slow build up of base cations in the soils. A scenario assuming deposition reduction to background levels of sulphur and nitrogen show that there remains potential for additional increases in ANC if deposition is reduced beyond the Gothenburg protocol. Target loads are considerably lower than critical loads for southern Norway, showing that deposition reductions below the critical load are needed if the goal is to restore conditions suitable for sustainable fish populations within a few decades. ; Statens Forurensningstilsyn

ABSTRACTThis paper presents data on the distribution of seven pesticides in an agricultural catchment which is located within the Agricultural Development and Advisory Service farm at Rosemaund, 11 km north‐east of Hereford, UK. Data for aldicarb, atrazine, carbofuran, dimethoate, MCPA and isoproturon, are available for both the soil and surface waters (drain and stream water), with simazine data available only for the stream. Measurements were taken before and after pesticide application, which was made following normal agricultural practice. Soil residue data showed the degradation rates of the pesticides to be within the range of literature values. Pesticide levels in the stream and drains during runoff events following rainfall ranged from below detection limits (typically 0.02‐0.1 μg/1), to 264 μg/1 (for carbofuran). Over 90% of the events had detectable maximum concentrations. The percentage of pesticide applied, which was removed during individual rainfall events, was calculated. The maximum value estimated was 1.1%, again for carbofuran. Most of the events gave values several orders of magnitude below this value.The data have been used to try to validate a range of models which could be used for screening new pesticides or for informing decisions on the use of existing pesticides. The results of the validations are summarized.

The hydrographic basin and variables, the water bodies such as rivers, lakes, ponds, streams, streams, canals, swamps, veredas, and the springs that constitute the surface waters, as well as the areas that protect them, APA's and APP's, are environmentally pressured since the emergence of cities, both in the need to provide food and housing, due to population growth and exploitation of natural resources. The objective of this research was to carry out a quantitative analysis of the academic productions on the state of conservation of the surface waters of the seven states of the northern region. The method applied was a systematic and bibliometric review, with a survey of documentary data whose temporal cut was between 1981 and 2020. The bases for this search were: Coordination of Improvement of Research and Studies in Higher Education (CAPES), Google Scholar, Scientif Electronic Library Online (SciELO), Scientific Periodicals Electronic Library (SPELL), and the repositories of federal universities in the northern region. The statistical treatment of the data was done with the use of Excel software from the application of Descriptive Statistics. The data obtained and analyzed indicated that in the seven states ( =12.7) of this region 168 surveys were made, of which 89 (n = 53.0%) are related to the eight selective descriptors: hydrographic basin (n = 13; 14.6%): sub-basins (n = 4; 4.5%); micro-basins and APA's (n = 3; 3.4%) each; APP's (n = 11; 12.3%); water quality (n =31; 34.8%); water bodies (n = 8; 9.0%), and springs (n = 16; 18.0%). These researches have indicated that the state of conservation, especially of the springs, is not adequate, although there are specific state legislations for their conservation, but in practice this does not occur, mainly when urban growth, agriculture and cattle raising are involved, besides mining, the most impacting of them.Key words: Hydrology, Hydrogeographic, Water quality, Urbanization

AbstractIn an extensive study of pesticides in a Chalk catchment, twenty pesticides were selected for study; and this paper reports the findings of an eighteen‐month programme of river and rainwater sampling. The results of periodic samples and an intensive river monitoring programme over the duration of a flood event are described.Both rain and river water within the catchment were found to contain significant numbers of pesticides at varying concentrations. The paper describes the values and temporal variations which were discovered. Higher concentrations and greater numbers of pesticides appeared to be brought down by floods and high river flows; however, even during low flows, some pesticides were persistently found in the river.