Emissions of nitrogen and phosphorus into rivers from agricultural land – selected controversial issues/ Ładunki azotu i fosforu wprowadzane do rzek z terenów rolniczych – wybrane dyskusyjne problemy

Abstract

The research methodology for determining the sources of nutrients responsible for the eutrophication of rivers and seas, as well as the extent of their load in particular drainage basins, has for many years been at the centre of vigorous discussion. In the Oder and Vistula river basin, apart from the calculation of monthly and annual loads of nitrogen and phosphorus, based on the discharge and chemical monitoring data of waters, the MONERIS (Modeling Nutrient Emissions in River Systems) model has also been applied in determining nutrient sources. This article, on the basis of a comprehensive review of the professional literature, shall cast a critical eye over six issues that have been at the centre of past robust discussion: 1) determining the balance of N and P in agriculture, 2) the effects of a significant improvement in sewage treatment, 3) impact of technology on agriculture, 4) determination of nutrient retention in drainage basins, 5) impact of tile drainage practices on the leaching of nutrients, 6) as well as the accuracy of calculations made according to the MONERIS model. It would appear that for practical purposes it is sufficient to determine given loads of N and P from the drainage basins of particular rivers, as well as to adjust the above mentioned model, or indeed -resign from the unproven methodology of determining nutrient sources in rivers.

The Functioning of a Water Body Within a Fluvio-Lacustrine System as an Effect of Excessive Nitrogen Loading—The Case of Lake Symsar and its Drainage Area (Northeastern Poland)

“…Nitrogen retention in wetlands is twice as high as in lakes-wetlands retain ca. 64% of the total cargo, compared to 34% in lakes and 2% in rivers [24]. It appears that the assimilation process depends on whether the retention occurs for a sufficiently long time (on a long-term basis) or only seasonally, because it later provides a basis for predicting the risk to aquatic ecosystems.…”

Dynamics of changes in surface water quality indicators of the Western Bug River basin within Ukraine using GIS technologies

“…Therefore, it is necessary to further introduce and implement measures aimed at restoring the quality of the water of the river basin by means of further reduction of discharges of sewage of settlements, construction of new and modernization of existing treatment facilities with a full cycle of sewage treatment, sewer networks, introduction of a system of fines for non-compliance with the requirements of the current water protection legislation [KLYMEN-KO, VOZNYUK 2010;KOZYTSKA, MUZYCHENKO 2015]. Solving these tasks requires improving the efficiency of the network of national and transboundary monitoring of surface water quality, creating organizational structures for the integrated management of the Western Bug basin, and integrating water protection measures by neighbouring states in accordance with the requirements [ILNICKI 2014;KLYMENKO, LIKHO 2009;KRENGEL еt al. 2018;ZABOKRY-TSKA 2011].…”

Spatio-temporal changes in water quality in an eutrophic lake with artificial aeration

“…Chlorophyll values for summers 2009, 2010, and 2011 were statistically different. Data analysis shows that the level of chlorophyll-a was significantly lower in 2010, a rainy year year factor (only for summer data); source: own study in relation to 2009and 2011. ILNICKI [2014 has recently suggested that point sources of P provide the most significant risk for eutrophication, even in rural areas with high agricultural losses where precipitation and runoff causes a large inter-annual nutrient load variability.…”