Browsing by Subject "huuhtoutuminen"

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  • Alasaarela, Erkki (Vesihallitus. National Board of Waters, 1982)
    Vesientutkimuslaitoksen julkaisuja 49, 3-16
    Kyrönjoen tulvasuojelutöiden aiheuttamista happamuusongelmista
  • Ekholm, Petri (Finnish Environment Institute, 1998)
    Monographs of the Boreal Environment Research 11
  • Kareinen, Timo; Nissinen, Ari; Ilvesniemi, Hannu (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1998)
    In this study we analyze how the ion concentrations in forest soil solution are determined by hydrological and biogeochemical processes. A dynamic model ACIDIC was developed, including processes common to dynamic soil acidification models. The model treats up to eight interacting layers and simulates soil hydrology, transpiration, root water and nutrient uptake, cation exchange, dissolution and reactions of Al hydroxides in solution, and the formation of carbonic acid and its dissociation products. It includes also a possibility to a simultaneous use of preferential and matrix flow paths, enabling the throughfall water to enter the deeper soil layers in macropores without first reacting with the upper layers. Three different combinations of routing the throughfall water via macro- and micropores through the soil profile is presented. The large vertical gradient in the observed total charge was simulated succesfully. According to the simulations, gradient is mostly caused by differences in the intensity of water uptake, sulfate adsorption and organic anion retention at the various depths. The temporal variations in Ca and Mg concentrations were simulated fairly well in all soil layers. For H+, Al and K there were much more variation in the observed than in the simulated concentrations. Flow in macropores is a possible explanation for the apparent disequilibrium of the cation exchange for H+ and K, as the solution H+ and K concentrations have great vertical gradients in soil. The amount of exchangeable H+ increased in the O and E horizons and decreased in the Bs1 and Bs2 horizons, the net change in whole soil profile being a decrease. A large part of the decrease of the exchangeable H+ in the illuvial B horizon was caused by sulfate adsorption. The model produces soil water amounts and solution ion concentrations which are comparable to the measured values, and it can be used in both hydrological and chemical studies of soils.
  • Rekolainen, Seppo (National Board of Waters and the Environment. Vesi- ja ympäristöhallitus, 1993)
    Publications of the Water and Environment Research Institute 12
    Yhteenveto: Maatalouden aiheuttama vesistönkuormitus ja sen vähentäminen
  • Kauppi, Lea (Vesihallitus, 1979)
    Vesientutkimuslaitoksen julkaisuja 30, 21-41
    Tiivistelmä: Valuma-alueen vaikutus fosforin ja typen hajakuormitukseen.
  • Puustinen, Markku (National Board of Waters and the Environment. Vesi- ja ympäristöhallitus, 1994)
    Publications of the Water and Environment Research Institute. 17
    Yhteenveto: Viljelymenetelmien vaikutus eroosioon ja ravinteiden huuhtoutumiseen
  • Pitkänen, Heikki (National Board of Waters and the Environment, 1994)
    Publications of the Water and Environment Research Institute 18
    Suomen rannikkovesien rehevöityminen: jokivesien tuomien ravinteiden alkuperä, käyttäytyminen ja vaikutukset.
  • Mattsson, Tuija (Finnish Environment Institute, 2010)
    Monographs of the Boreal Environment Research 36
    The terrestrial export of dissolved organic matter (DOM) is associated with climate, vegetation and land use, and thus is under the influence of climatic variability and human interference with terrestrial ecosystems, their soils and hydrological cycles. The present study provides an assessment of spatial variation of DOM concentrations and export, and interactions between DOM, catchment characteristics, land use and climatic factors in boreal catchments. The influence of catchment characteristics, land use and climatic drivers on the concentrations and export of total organic carbon (TOC), total organic nitrogen (TON) and dissolved organic phosphorus (DOP) was estimated using stream water quality, forest inventory and climatic data from 42 Finnish pristine forested headwater catchments, and water quality monitoring, GIS land use, forest inventory and climatic data from the 36 main Finnish rivers (and their sub-catchments) flowing to the Baltic Sea. Moreover, the export of DOM in relation to land use along a European climatic gradient was studied using river water quality and land use data from four European areas. Additionally, the role of organic and minerogenic acidity in controlling pH levels in Finnish rivers and pristine streams was studied by measuring organic anion, sulphate (SO4) and base cation (Ca, Mg, K and Na) concentrations. In all study catchments, TOC was a major fraction of DOM, with much lower proportions of TON and DOP. Moreover, most of TOC and TON was in a dissolved form. The correlation between TOC and TON concentrations was strong and TOC concentrations explained 78% of the variation in TON concentrations in pristine headwater streams. In a subgroup of 20 headwater catchments with similar climatic conditions and low N deposition in eastern Finland, the proportion of peatlands in the catchment and the proportion of Norway spruce (Picea abies Karsten) of the tree stand had the strongest correlation with the TOC and TON concentrations and export. In Finnish river basins, TOC export increased with the increasing proportion of peatland in the catchment, whereas TON export increased with increasing extent of agricultural land. The highest DOP concentrations and export were recorded in river basins with a high extent of agricultural land and urban areas, reflecting the influence of human impact on DOP loads. However, the most important predictor for TOC, TON and DOP export in Finnish rivers was the proportion of upstream lakes in the catchment. The higher the upstream lake percentage, the lower the export, indicating organic matter retention in lakes. Molar TOC:TON ratio decreased from headwater catchments covered by forests and peatlands to the large river basins with mixed land use, emphasising the effect of the land use gradient on the stoichiometry of rivers. This study also demonstrated that the land use of the catchments is related to both organic and minerogenic acidity in rivers and pristine headwater streams. Organic anion dominated in rivers and streams situated in northern Finland, reflecting the higher extent of peatlands in these areas, whereas SO4 dominated in southern Finland and on western coastal areas, where the extent of fertile areas, agricultural land, urban areas, acid sulphate soils, and sulphate deposition is highest. High TOC concentrations decreased pH values in the stream and river water, whereas no correlation between SO4 concentrations and pH was observed. This underlines the importance of organic acids in controlling pH levels in Finnish pristine headwater streams and main rivers. High SO4 concentrations were associated with high base cation concentrations and fertile areas, which buffered the effects of SO4 on pH.
  • Lepistö, Ahti (Finnish Environment Institute, 1996)
    Monographs of the Boreal Environment Research 1
  • Kohonen, Tapani (Vesihallitus, 1982)
    Vesientutkimuslaitoksen julkaisuja 27
    Tiivistelmä: Havaintotiheyden vaikutus valumavesien laatuarvioihin
  • Räike, Antti; Koskela, Jarkko; Knuuttila, Seppo; Lehtoranta, Jouni; Pitkänen, Heikki; Risto, Maarit; Vuorinen, Jyrki (Finnish Environment Institute, 2015)
    Reports of the Finnish Environment Institute 3/2015
    The report describes the results of the joint Polish–Finnish sampling expedition aimed at estimating the possible effects of the two Polish phosphogypsum stacks located in Wislinka (Gdańsk) and Police on the loading of the Baltic Sea and the nearby watercourses. The joint expedition was based on the agreement between the Polish and Finnish Ministers of the Environment in June 2013. The results indicate a clear effect of the phosphogypsum stack on phosphate and total phosphorus concentrations in the Martwa Wisla. The physical nature of the basin with no permanent flow into the sea weakens mixing and dilution and may cause a local enrichment of pollutants from external sources, compared with a normal river having a constant water flow into the sea. Our suggestion is that a comprehensive study should be carried out in the stack area of Wislinka, as well as in the Martwa Wisla and its catchment area, to be able to calculate water and phosphorus mass balances in the area, and the magnitude of inputs of phosphorus to the Baltic Sea caused by the stack. The role of sediments as sinks and sources of phosphorus and other pollutants in the Martwa Wisla should be studied as well. In Police the effects of the phosphogypsum stack were less obvious. This could be expected as a result of effective mixing and dilution due to the high flow in the Oder River. Additionally, measures have been implemented to prevent leakage, by means of a hydraulic barrier and by collecting runoff water and directing it to the local wastewater treatment plant (WWTP). However, the results of the present expedition and also the results of the local monitoring programme from 2008 to 2012 indicate that the effects of the phosphogypsum stack on the quality of the recipient water cannot be ruled out. In order to estimate possible leakages in Police we suggest that an intensive monitoring programme for both groundwater and surface waters would be initiated. The sampling frequency for monitoring the leakage from the phosphogypsum stack should be increased to at least 12 annual samples at both the upstream and downstream stations. In addition, the water flow of the Oder between the stack and the nearby island should be continuously monitored. This would enable a reliable estimation of the potential phosphorus load into the Baltic Sea caused by the stack.
  • Launiainen, Samuli; Sarkkola, Sakari; Laurén, Ari; Puustinen, Markku; Tattari, Sirkka; Mattsson, Tuija; Piirainen, Sirpa; Heinonen, Jaakko; Alakukku, Laura; Finér, Leena (Suomen ympäristökeskus, 2014)
    Suomen ympäristökeskuksen raportteja 33/2014
    Maankäytöstä ja muusta ihmistoiminnasta aiheutuu lähes aina luonnon taustakuorman ylittävää ravinne- ja kiintoainekuormitusta vesistöihin. Julkaisussa esitellään valuma-alueelta vesistöön kohdistuvan kokonaistypen, kokonaisfosforin ja kiintoaineen kuormituksen arviointiin kehitetty KUSTAA -työkalu. KUSTAA perustuu ominaiskuormitusmenetelmään ja kattaa tyypillisimpiin maankäyttömuotoihin liittyvät toimenpiteet ja muut haja- ja pistekuormituslähteet. Kuormitusarvion lähtötiedoiksi tarvitaan valuma-alueen pinta-ala, sen vesistöjen pinta-ala, metsä- ja maataloustoimenpiteiden pinta-alat ja muut haja- ja pistekuormituslähteiden määrät vuositasolla. Tietojen perusteella tuotetaan arvio valuma-alueen kokonaiskuormituksesta ja sen jakautumisesta eri lähteisiin. Lisäksi esitetään yksinkertainen epävarmuusarvio. KUSTAA -työkalu on integroitu taulukkolaskentaympäristöön ja tarkoitettu käytännön toimijoiden käyttöön. Sen avulla voidaan arvioida esimerkiksi maankäytössä tapahtuvien muutosten, pistekuormituksen hallinnan tai yksittäisen kuormituslähteen vaikutuksia valuma-alueen kokonaiskuormitukseen. Julkaisussa kootaan kattavasti yhteen tyypillisimpiä maankäyttömuotoja ja haja- ja pistekuormituslähteitä edustavat ominaiskuormitusluvut ja esitellään KUSTAA -työkalun käyttöä esimerkkilaskelmien avulla.
  • Wade, Andrew J.; Skeffington, Richard A.; Couture, Raoul-Marie; Erlandsson Lampa, Martin; Groot, Simon; Halliday, Sarah J.; Harezlak, Valesca; Hejzlar, Josef; Jackson-Blake, Leah A.; Lepistö, Ahti; Papastergiadou, Eva; Riera, Joan Lluís; Rankinen, Katri; Shahgedanova, Maria; Trolle, Dennis; Whitehead, Paul G.; Psaltopoulos, Demetris; Skuras, Dimitris (MDPI AG, 2022)
    Recent studies have demonstrated that projected climate change will likely enhance nitrogen (N) and phosphorus (P) loss from farms and farmland, with the potential to worsen freshwater eutrophication. Here, we investigate the relative importance of the climate and land use drivers of nutrient loss in nine study catchments in Europe and a neighboring country (Turkey), ranging in area from 50 to 12,000 km2. The aim was to quantify whether planned large-scale, land use change aimed at N and P loss reduction would be effective given projected climate change. To this end, catchment-scale biophysical models were applied within a common framework to quantify the integrated effects of projected changes in climate, land use (including wastewater inputs), N deposition, and water use on river and lake water quantity and quality for the mid-21st century. The proposed land use changes were derived from catchment stakeholder workshops, and the assessment quantified changes in mean annual N and P concentrations and loads. At most of the sites, the projected effects of climate change alone on nutrient concentrations and loads were small, whilst land use changes had a larger effect and were of sufficient magnitude that, overall, a move to more environmentally focused farming achieved a reduction in N and P concentrations and loads despite projected climate change. However, at Beyşehir lake in Turkey, increased temperatures and lower precipitation reduced water flows considerably, making climate change, rather than more intensive nutrient usage, the greatest threat to the freshwater ecosystem. Individual site responses did however vary and were dependent on the balance of diffuse and point source inputs. Simulated lake chlorophyll-a changes were not generally proportional to changes in nutrient loading. Further work is required to accurately simulate the flow and water quality extremes and determine how reductions in freshwater N and P translate into an aquatic ecosystem response.
  • Nieminen, Mika; Sarkkola, Sakari; Hasselquist, Eliza Maher; Sallantaus, Tapani (Kluwer Academic Publishers, 2021)
    Water, Air, & Soil Pollution 232 (2021), 371
    Contradictory results for the long-term evolution of nitrogen and phosphorus concentrations in waters discharging from drained peatland forests need reconciliation. We gathered long-term (10–29 years) water quality data from 29 forested catchments, 18 forestry-drained and 11 undrained peatlands. Trend analysis of the nitrogen and phosphorus concentration data indicated variable trends from clearly decreasing to considerably increasing temporal trends. While the variations in phosphorus concentration trends over time did not correlate with any of our explanatory factors, trends in nitrogen concentrations correlated positively with tree stand volume in the catchments and temperature sum. A positive correlation of increasing nitrogen concentrations with temperature sum raises concerns of the future evolution of nitrogen dynamics under a warming climate. Furthermore, the correlation with tree stand volume is troublesome due to the generally accepted policy to tackle the climate crisis by enhancing tree growth. However, future research is still needed to assess which are the actual processes related to stand volume and temperature sum that contribute to increasing TN concentrations.
  • Knuutila, Kati (Helsingfors universitet, 2017)
    The soil mineral nitrogen content is affected by many factors such as nitrogen fertilizer, fertilization and cultivated plant species. The effects of these factors on soil mineral nitrogen content were examined and the research was conducted at the Viikki Research Farm during 2013–2015. The possibility of using soil mineral nitrogen content and nitrogen balance to optimise nitrogen fertilization was also studied as well as the leaching of mineral nitrogen during winter and the factors affecting leaching. The soil type of the experimental area was clay loam in topsoil and sandy loam in subsoil. Soil samples were taken in the spring before tillage and in the autumn before soil freezing from topsoil (0-20 cm) and subsoil (30-50 cm). Ammonium and nitrate were extracted from soil samples with 2 M KCl. Plant species and fertilization changed every year, but fertilization followed the regulations for the subsidies of agricultural environment and all the fertilizers and cultivars were commercially available in Finland. The nitrogen content of the seed and forage samples were determined. The actual nitrogen yield and nitrogen balance were calculated. The expected nitrogen yield and nitrogen balance were calculated with the common nitrogen contents of seeds published by the Finnish Agency for Rural Affairs and compared to the actual nitrogen yield and nitrogen balance, but no differences were found. Soil mineral nitrogen content, nitrogen balance and nitrogen yield varied a lot from year to year which was partly caused by the differences between the growing seasons and winters as well as the changes of cultivated plants and fertilization. The soil mineral nitrogen content was smaller in the spring (33 N kg/ha) than in the autumn (55 N kg/ha). Grass took more nitrogen than the other plant species. The soil nitrate content was smaller under growing grass than harvested plant stand in the autumn and the ammonium content was greater under growing grass than other plant species in the spring. The soil mineral nitrogen content was reduced and differences between treatments were moderated during the winter, which was probably caused by leaching. Fertilization had no direct effect on soil mineral nitrogen content. Increasing nitrogen fertilization increased nitrogen balance, but there was no correlation between nitrogen balance and soil mineral nitrogen content.
  • Mussaari, Ismo (Vesihallitus, 1974)
    Vesihallitus. Tiedotus 79
    Agricultute as a contributor to water pollution in Southwestern Finland.
  • Nieminen, Mika; Sarkkola, Sakari; Haahti, Kersti; Sallantaus, Tapani; Koskinen, Markku; Ojanen, Paavo (Suoseura, 2020)
    Suo - tutkimusartikkelit
    Viime vuosina julkaistujen tutkimusten mukaan metsäojitettujen soiden vesistö kuormituksen epäillään olevan moninkertaisesti aiemmin arvioitua suurempaa. Syynä tähän on se, että kuormitusta syntyy aiemmista käsityksistä poiketen silloinkin, kun ojitusalueilla ei ole vuosikausiin tehty mitään toimenpiteitä. Tässä työssä arvioitiin metsäojitusalueilta syntyvä vesistökuormitus ottamalla huomioon sekä tämä nykyisistä metsätaloustoimenpiteistä riippumaton ”ojituslisä” että kunnostusojituksen, lannoituksen ja hakkuiden aiheuttama kuormitus. Tehdyn arvion mukaan metsätaloudesta ojitetuilla soilla syntyy Suomessa vuosittain typpikuormitusta noin 8500 Mg ja fosforikuormi tusta 590 Mg. Kun ojituslisä otetaan huomioon, typpikuormitus on noin 18-kertainen ja fosforikuormitus 6–7-kertainen aiempiin vain eri toimenpiteiden kuormitukset huomioon ottaviin arvioihin verrattuna. Vesiensuojelun kannalta oleellista olisi selvittää, mitkä tekijät ojitusalueilla aiheuttavat ojituslisän muodossa tapahtuvaa pysyvää kuormitusta ja mitä tämän kuormituksen torjumiseksi on tehtävissä.
  • Nieminen, Mika; Sallantaus, Tapani (Suoseura, 2020)
    Suo 72(1) (2020)
  • Rankinen, Katri; Turtola, Eila; Lemola, Riitta; Futter, Martyn; Cano Bernal, José Enrique (Molecular Diversity Preservation International (MDPI), 2021)
    Water 2021, 13(4), 450
    Increased nutrient loading causes deterioration of receiving surface waters in areas of intensive agriculture. While nitrate and particulate phosphorus load can be efficiently controlled by reducing tillage frequency and increasing vegetation cover, many field studies have shown simultaneously increased loading of bioavailable phosphorus. In the latest phase of the Rural Programme of EU agri-environmental measures, the highest potential to reduce the nutrient loading to receiving waters were the maximum limits for fertilization of arable crops and retaining plant cover on fields with, e.g., no-till methods and uncultivated nature management fields. Due to the latter two measures, the area of vegetation cover has increased since 1995, suggesting clear effects on nutrient loading in the catchment scale as well. We modeled the effectiveness of agri-environmental measures to reduce phosphorus and nitrogen loads to waters and additionally tested the performance of the dynamic, process-based INCA-P (Integrated Nutrients in Catchments—Phosphorus) model to simulate P dynamics in an agricultural catchment. We concluded that INCA-P was able to simulate both fast (immediate) and slow (non-immediate) processes that influence P loading from catchments. Based on our model simulations, it was also evident that no-till methods had increased bioavailable P load to receiving waters, even though total P and total N loading were reduced.
  • Kauppi, Lea (Vesihallitus, 1975)
    Vesihallitus. Tiedotus 84
    English summary: The washing out of organic matter and factors affecting it.