Browsing by Subject "Water quality"

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  • Doshi, Bhairavi; Hietala, Sami; Sirviö, Juho Antti; Repo, Eveliina; Sillanpää, Mika (2019)
    The traces of hazardous chemicals used in oil spill response have harmed marine creatures with long-term cytoxic impacts, so, a greener alternative is to use biodegradable components in the dispersant formulation. This study demonstrates the efficiency of carboxymethylated and acylated chitosan combined with powdered orange peel (OP-D) in the emulsification of marine diesel and 2 T-oil with different qualities of water. OP-D particles undergo Pickering emulsions, whereas the amphiphilic behaviour of the Blend and hydrophobically modified carboxymethyl chitosan-orange peels (CSOP-A) favours conventional emulsions through steric and electrostatic stabilization. The emulsion formation rate was maximum with OP-D in saline water and autonomous of the water quality with Blend. Additionally, different hydrophobic moieties on the surface of the Blend and CSOP-A affected the oil droplets' stabilization rate. Changing pH altered the surface properties of particles and hence the nature of the formed emulsion range from gel-like to creamy, suggesting particle-particle to particle-oil interactions. An increase in electrolyte concentration enhanced the coalescence rate of marine diesel with CSOP-A. The oil droplet size in the formed emulsion increases with a temperature decrease up to 2 °C, and the emulsion stabilization rate was
  • Kinnunen, Niko; Laurén, Annamari (Ari); Pumpanen, Jukka; Nieminen, Tiina M.; Palviainen, Marjo (2021)
    A 96-h laboratory experiment was conducted to assess the potential of biochar as a water protection tool for acid sulfate soil runoff. Acid sulfate soils pose a risk to water bodies due to acid, metal-rich runoff, especially in drained peatland forests. New water protection methods, such as adsorption with biochar, are needed. We investigated the capability of spruce and birch biochar to adsorb metals and reduce acidity in the water. Water from an acid sulfate site was stirred with biochar, biochar with lime, and biochar with ash. We determined water Al, S, Fe, Cu, Co, Cd, Ni, and Zn concentrations periodically, as well as pH and total organic carbon at the beginning and the end of the experiment. The studied substances are considered the most abundant and environmentally harmful elements in the acid sulfate soils in Finland. Biochar surface characteristics were analyzed with FTIR spectroscopy. Concentration changes were used to parametrize adsorption kinetics models. Biochar adsorbed metals and increased pH, but lime and ash additives did not always improve the adsorption. Spruce biochar and ash addition had generally higher adsorption than birch biochar and lime addition. The adsorption was dominated by Al and Fe at lower pH, while increasing pH improved the adsorption of Cd and Zn. The results show that biochar can increase the water pH, as well as adsorb Al, Fe, Co, Cd, Ni, and Zn. Further work could include an actual-scale biochar reactor in a laboratory and field conditions.
  • Odeh, Issam; Arar, Sharif; Al-Hunaiti, Afnan; Sa'aydeh, Hiyam; Hammad, Ghada; Duplissy, Jonathan; Vuollekoski, Henri; Korpela, Antti; Petäjä, Tuukka; Kulmala, Markku; Hussein, Tareq (2017)
    The quality and chemical composition of urban dew collections with dust precipitates without pre-cleaning of the collecting surface WSF (white standard foil) were investigated for 16 out of 20 collected samples with collected volumes ranging from 22 to 230 ml. The collection period was from March to July 2015 at an urban area, Jubaiha, which is located in the northern part of the capital city Amman, Jordan. The obtained results indicated the predominance of Ca2+ and SO42- ions (ratio 2.2: 1) that originated from Saharan soil dust; where the collected samples were alkaline (mean pH = 7.35) with high mineralization (429.22 mg/L) exceeding the previously reported dew values in Amman-Jordan. A relocation of NaCl and to a less extent Mg2+ from sea to land by Saharan wind is indicated by the percent sea-salt fraction calculations (over 100 and 52, respectively). The collected samples exhibited high total organic carbon (TOC) values ranging from 11.86 to 74.60 mg/L, presence of particulate settled material with turbidity ranging from 20.10 to 520.00 NTU, and presence of undesired elements like boron (mean = 1.48 mg/L) that made it different in properties from other dew water collections at clean surfaces, and exceeding the standard limits for drinking water for these parameters set by Jordanian Drinking Water standards (JS286/2015)/WHO standard. The quality of this water is more close to that for raw or agricultural water but if it is meant to be used as potable source of water, at least sand and activated charcoal filters are needed to purify it.
  • Nieminen, M.; Hökkä, H.; Laiho, R.; Juutinen, A.; Ahtikoski, A.; Pearson, M.; Kojola, S.; Sarkkola, S.; Launiainen, S.; Valkonen, S.; Penttilä, T.; Lohila, A.; Saarinen, M.; Haahti, K.; Makipää, R.; Miettinen, J.; Ollikainen, M. (2018)
    Environmental and economic performance of forestry on drained peatlands was reviewed to consider whether continuous cover forestry (CCF) could be a feasible alternative to even-aged management (EM). CCF was regarded feasible particularly because continuously maintaining a tree stand with significant transpiration and interception capacity would decrease the need for ditch network maintenance. Managing CCF forests in such a way that the ground water levels are lower than in clear-cut EM forests but higher than in mature EM forests could decrease greenhouse gas emissions and negative water quality impacts caused both by anoxic redox reactions and oxidation and mineralization of deep peat layers. Regeneration studies indicated potential for satisfactory natural regeneration under CCF on drained peatlands. An economic advantage in CCF over EM is that fewer investments are needed to establish the forest stand and sustain its growth. Thus, even if the growth of trees in CCF forests were lower than in EM forests, CCF could at least in some peatland sites turn out to be a more profitable forest management regime. An advantage of CCF from the viewpoint of socially optimal forest management is that it plausibly reduces the negative externalities of management compared to EM. We propose that future research in drained peatland forests should focus on assessing the economic and environmental feasibility of CCF.
  • Bartosova, Alena; Capell, René; Olesen, Jørgen E.; Jabloun, Mohamed; Refsgaard, Jens Christian; Donnelly, Chantal; Hyytiäinen, Kari; Pihlainen, Sampo; Zandersen, Marianne; Arheimer, Berit (2019)
    The Baltic Sea is suffering from eutrophication caused by nutrient discharges from land to sea, and these loads might change in a changing climate. We show that the impact from climate change by mid-century is probably less than the direct impact of changing socioeconomic factors such as land use, agricultural practices, atmospheric deposition, and wastewater emissions. We compare results from dynamic modelling of nutrient loads to the Baltic Sea under projections of climate change and scenarios for shared socioeconomic pathways. Average nutrient loads are projected to increase by 8% and 14% for nitrogen and phosphorus, respectively, in response to climate change scenarios. In contrast, changes in the socioeconomic drivers can lead to a decrease of 13% and 6% or an increase of 11% and 9% in nitrogen and phosphorus loads, respectively, depending on the pathway. This indicates that policy decisions still play a major role in climate adaptation and in managing eutrophication in the Baltic Sea region.
  • Roy, Kushal; Karim, Md. Rezaul; Akter, Farjana; Islam, Md. Safiqul; Ahmed, Kousik; Rahman, Masudur; Datta, Dilip Kumar; Khan, M. Shah Alam (2018)
    Despite its complexity and importance in managing water resources in populous deltas, especially in tidal areas, literatures on tidal rivers and their land use linkage in connection to water quality and pollution are rare. Such information is of prior need for Integrated Water Resource Management in water scarce and climate change vulnerable regions, such as the southwestern coast of Bangladesh. Using water quality indices and multivariate analysis, we present here the land use signatures of a dying tidal river due to anthropogenic perturbation. Correlation matrix, hierarchical cluster analysis, factor analysis, and bio-geo-chemical fingerprints were used to quantify the hydro-chemical and anthropogenic processes and identify factors influencing the ionic concentrations. The results show remarkable spatial and temporal variations (p <0.05) in water quality parameters. The lowest solute concentrations are observed at the mid reach of the stream where the agricultural and urban wastewater mix. Agricultural sites show higher concentration of DO, Na+ and K+ reflecting the effects of tidal spill-over and shrimp wastewater effluents nearby. Higher level of Salinity, EC, Cl-, HCO3 (-), NO3 (-), PO4 (3-) and TSS characterize the urban sites indicating a signature of land use dominated by direct discharge of household organic waste into the waters. The spatial variation in overall water quality suggests a periodic enhancement of quality especially for irrigation and non-drinking purposes during monsoon and post-monsoon, indicating significant influence of amount of rainfall in the basin. We recommend that, given the recent trend of increasing precipitation and ground water table decrease, such dying tidal river basins may serve as excellent surface water reservoir to supplement quality water supply to the region.
  • Ovaskainen, Otso Tapio; Weigel, Benjamin Matthias; Potyutko, Oleg; Buyvolov, Yury (2019)
    Scale-related assessment strategies are important contributions to successful ecosystem management. With varying impact of environmental drivers from local to regional scales, a focal task is to understand scale-de- pendent responses when assessing the state of an ecosystem. In this study we use large-scale monitoring data, spanning 40 years and including four aquatic bioindicator groups (phytoplankton, zooplankton, periphyton, zoobenthos) to expose the long-term changes of water quality across Russia. We include four hierarchical spatial scales (region, basin, waterbody and observation point) to identify the relative importance of different spatio- temporal scales for the variation of each bioindicator and patterns of co-variation among the bioindicators at different hierarchical levels. We analysed the data with Hierarchical Modelling of Species Communities (HMSC), an approach that belongs to the framework of joint species distribution models. We performed a cross validation to reveal the predictive power of modelled bioindicator variation, partitioned explained variance among the fixed effects (waterbody type, and influence of human population density) and the random effects (spatial and spatio-temporal variation at the four hierarchical scales), and examined the co-variation among bioindicators at each spatio-temporal scale. We detected generally decreasing water quality across Russian freshwaters, yet with region and bioindicator specific trends. For all bioindicators, the dominating part of the variation was attributed the largest (region) and smallest (observation point) hierarchical scales, the region particularly important for benthic and the observation point for pelagic bioindicators. All bioindicators captured the same spatial variation in water quality at the smallest scale of observation point, with phytoplankton, zooplankton and periphyton being associated positively to each other and negatively to zoobenthos. However, at larger spatial scales and at spatio-temporal scales, the associations among the bioindicators became more complex, with phytoplankton and zooplankton showing opposite trends over time. Our study reveals the sensitivity of bioindicators to spatial and temporal scales. While delivering unidirectional robust water quality assessments at the local scale, bioindicator co-variation is more complex over larger geographic scales and over time.
  • Tattari, Sirkka; Koskiaho, Jari; Kosunen, Maiju; Lepisto, Ahti; Linjama, Jarmo; Puustinen, Markku (2017)
    Long-term data from a network of intensively monitored research catchments in Finland was analysed. We studied temporal (1981-2010) and spatial variability in nitrogen (N) and phosphorus (P), from 1987 losses, both from agricultural and forestry land. Based on trend analysis, total nitrogen (TN) concentrations increased in two of the four agricultural sites and in most of the forested sites. In agricultural catchments, the total phosphorus (TP) trends were decreasing in two of the four catchments studied. Dissolved P (DRP) concentrations increased in two catchments and decreased in one. The increase in DRP concentration can be a result of reducing erosion by increased non-plough cultivation and direct sowing. In forested catchments, the TP trends in 1987-2011 were significantly decreasing in three of the six catchments, while DRP concentrations decreased significantly in all sites. At the same time, P fertilisation in Finnish forests has decreased significantly, thus contributing to these changes. The mean annual specific loss for agricultural land was on average 15.5 kg ha(-1) year(-1) for N and 1.1 kg ha(-1) year(-1) for P. In the national scale, total TN loading from agriculture varied between 34,000-37,000 t year(-1) and total P loading 2400-2700 t year(-1) These new load estimates are of the same order than those reported earlier, emphasising the need for more efforts with wide-ranging and carefully targeted implementation of water protection measures.
  • Räsänen, Aleksi; Schönach, Paula; Jurgilevich, Alexandra; Heikkinen, Milja; Juhola, Sirkku (2019)
    To tackle problems related to water quantity and quality, transformations in water management systems have become of increasing interest. Transformative capacity can be defined as the ability first to adapt to changes, and if needed, to carry out fundamental changes in a specific system. Using a framework of ten components of transformative capacity and an analysis of earlier historical research, policy documents and data gathered in a stakeholder scenario workshop, we examine the relationship between past and future transformations and transformative capacity in river basin management in the River Vantaa basin, located in southern Finland. In the past, River Vantaa was heavily polluted by municipal wastewater. The water quality has gradually improved but is still not considered good. The most successful changes have been concentrated on point source pollution, such as municipal wastewater, and they have mostly been driven by public administration and municipal coordination. In the future, more effort should be put on diffuse pollution, especially agricultural loading, and this requires changes in societal values and new forms of governance. We show how the past transformations have partly been driven by transformative capacity, but some transformations have enabled changes in the components of transformative capacity, indicating the interconnectedness of the different components. Furthermore, the interplay between transformations and transformative capacity occurs across spatial and temporal scales. We discuss how transformations take time, how transformative capacity evolves over longer time-spans, and how capacity and trajectories in local and wider scales are in a continuous interaction.
  • Lepparanta, Matti; Lewis, John E.; Heini, Anniina; Arvola, Lauri (2018)
    Spatial variability, an essential characteristic of lake ecosystems, has often been neglected in field research and monitoring. In this study, we apply spatial statistical methods for the key physics and chemistry variables and chlorophyll a over eight sampling dates in two consecutive years in a large (area 103 km(2)) eutrophic boreal lake in southern Finland. In the four summer sampling dates, the water body was vertically and horizontally heterogenic except with color and DOC, in the two winter ice-covered dates DO was vertically stratified, while in the two autumn dates, no significant spatial differences in any of the measured variables were found. Chlorophyll a concentration was one order of magnitude lower under the ice cover than in open water. The Moran statistic for spatial correlation was significant for chlorophyll a and NO2+NO3-N in all summer situations and for dissolved oxygen and pH in three cases. In summer, the mass centers of the chemicals were within 1.5 km from the geometric center of the lake, and the 2nd moment radius ranged in 3.7-4.1 km respective to 3.9 km for the homogeneous situation. The lateral length scales of the studied variables were 1.5-2.5 km, about 1 km longer in the surface layer. The detected spatial "noise" strongly suggests that besides vertical variation also the horizontal variation in eutrophic lakes, in particular, should be considered when the ecosystems are monitored.
  • Yli-Halla, Markku; Lötjönen, Timo; Kekkonen, Jarkko; Virtanen, Seija; Marttila, Hannu; Liimatainen, Maarit; Saari, Markus; Mikkola, Jarmo; Suomela, Raija; Joki-Tokola, Erkki (2022)
    The off-site effects of agricultural organic soils include the leaching of N, P, and organic carbon (OC) to watercourses and CO2, CH4, and N2O emissions into the atmosphere. The aim of this study was to quantify how the thickness of organic layers affects these loads. A 19.56-ha experimental field drained by subsurface pipes was established in Ruukki, northwestern Finland. Three plots had a 60–80 cm-thick sedge peat layer and three others had a thickness of 20 cm or less. The drainage pipes lie in mineral soil that, in this field, contains sulfidic material. This study documents the experimental settings and reports on the leaching of substances in the first two years, as well as CO2, CH4 and N2O emissions during eight weeks in one summer. Total N (TN) and OC loads were higher from the thicker peat plots. The mean TN loads during a hydrological year were 15.4 and 9.2 kg ha-1 from the thicker and thinner peat plots, respectively, with organic N representing 36% of TN load. Total P (TP) load averaged 0.27 kg ha-1 yr-1. Dissolved P load represented 63 and 36% of TP in the thicker peat area and only 23 and 13% in the thinner peat area, and was thus increased upon peat thickness. These N and P loads through the subsurface drainage system represented roughly 83% of TN and 64% of TP loads from this field. There were no clear differences in greenhouse gas emissions among the plots during the eight-week monitoring period. Slowly oxidizing sulfide in the subsoil resulted in annual leaching of 147 kg S ha-1, almost ten times that of non-sulfidic soils. Our first results emphasize the effect of the peat thickness on the leaching of substances and warn about considering all organic soils as a single group in environmental assessments.
  • Juutinen, Artti; Saarimaa, Miia; Ojanen, Paavo; Sarkkola, Sakari; Haara, Arto; Karhu, Jouni; Nieminen, Mika; Minkkinen, Kari; Penttila, Timo; Laatikainen, Matti; Tolvanen, Anne (2019)
    Economic development creates challenges for land-use planners in balancing between increasing the use of natural resources and safeguarding biodiversity and ecosystem services. We developed and utilized multi-objective numeric optimization models to analyze the trade-offs between biodiversity and ecosystem services (BES). The approach was used in the land-use planning process in northern Finland when selecting potential peat production sites as a part of the development of the regional master plan. We first quantified Net Present Value (NPV) of peat production, biodiversity, greenhouse gas (GHG) emissions, and water emissions of peatlands. Then we applied multi-objective optimization to examine the trade-offs between the variables as well as to determine a cost-efficient selection of potential peat production sites, that is, a selection which would simultaneously generate the greatest possible economic returns and environmental benefits. Our results showed that with a relatively small decrease in NPV, a substantial decrease in biodiversity loss and a reduction in water emissions compared to the benchmark level could be attained. However, a significant decrease in GHG emissions resulted in a substantial decrease in NPV. We conclude that it is possible to significantly improve land-use management by applying multi-objective optimization in land-use planning.
  • Palviainen, Marjo; Peltomaa, Elina; Laurén, Ari; Kinnunen, Niko; Ojala, Anne; Berninger, Frank; Zhu, Xudan; Pumpanen, Jukka (2022)
    Boreal peatiands are major sources of nitrogen (N), phosphorus (P) and dissolved organic carbon (DOC) to downstream aquatic ecosystems, and forest harvesting generally further increases the loading of DOC and nutrients. Continuous cover forestry (CCF) is proposed to be an environmentally more sustainable management option for peatland forests than conventional even-aged clear-cutting. However, the impacts of CCF on water quality, the biodegradability of DOC and consequent CO2 emissions from inland waters are poorly known. We studied the concentrations of N, P and DOC, the quality of DOC, and the mineralization of DOC to CO2 in ground water and ditch water in clear-cut, partially harvested, i.e. CCF, and uncut drained forests in Finland. Groundwater total N, NH4-N and PO4-P concentrations were significantly lower in CCF and uncut forest than in the clear-cut forest. Groundwater DOC concentrations were often highest in the clear-cut forest, where the water table was doser to the soil surface. Ditch water DOC and N concentrations were lowest next to the clear-cut area. DOC aromaticity in ground water was higher in the uncut forest than in the clear-cut and CCF, whereas ditch water aromaticity did not differ between the treatments. The biodegradation of DOC was studied by incubating water (at 15 degrees C for 24 h) 1, 3, 7 and 21 days after sampling. The results indicated that the majority of the CO2 production took place during the first three days, and CO2 fluxes were considerably higher from the ditch water than from the groundwater. The CO2 emissions were lower in summer than in the other seasons. Ditch water and groundwater CO2 production were generally significantly higher in the clear-cut than in the uncut forest. The results suggest that CCF can decrease the nutrient concentrations as well as CO2 emissions from inland waters compared to conventional clear-cutting. (C) 2021 The Authors. Published by Elsevier B.V.