Browsing by Subject "water"

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  • Bhattacharjee, Joy; Rabbil, Mehedi; Fazel, Nasim; Darabi, Hamid; Choubin, Bahram; Khan, Md. Motiur Rahman; Marttila, Hannu; Haghighi, Ali Torabi (Elsevier, 2021)
    Science of the Total Environment 797 (2021), 149034
    Lake water level fluctuation is a function of hydro-meteorological components, namely input, and output to the system. The combination of these components from in-situ and remote sensing sources has been used in this study to define multiple scenarios, which are the major explanatory pathways to assess lake water levels. The goal is to analyze each scenario through the application of the water balance equation to simulate lake water levels. The largest lake in Iran, Lake Urmia, has been selected in this study as it needs a great deal of attention in terms of water management issues. We ran a monthly water balance simulation of nineteen scenarios for Lake Urmia from 2003 to 2007 by applying different combinations of data, including observed and remotely sensed water level, flow, evaporation, and rainfall. We used readily available water level data from Hydrosat, Hydroweb, and DAHITI platforms; evapotranspiration from MODIS and rainfall from TRMM. The analysis suggests that the consideration of field data in the algorithm as the initial water level can reproduce the fluctuation of Lake Urmia water level in the best way. The scenario that combines in-situ meteorological components is the closest match to the observed water level of Lake Urmia. Almost all scenarios showed good dynamics with the field water level, but we found that nine out of nineteen scenarios did not vary significantly in terms of dynamics. The results also reveal that, even without any field data, the proposed scenario, which consists entirely of remote sensing components, is capable of estimating water level fluctuation in a lake. The analysis also explains the necessity of using proper data sources to act on water regulations and managerial decisions to understand the temporal phenomenon not only for Lake Urmia but also for other lakes in semi-arid regions.
  • Pilla, Rachel M.; Williamson, Graig E.; Adamovich, Boris V.; Adrian, Rita; Anneville, Orlane; Chandra, Sudeep; Colom-Montero, William; Devlin, Shawn P.; Dix, Margaret A; Dokulil, Martin T.; Gaiser, Evelyn E.; Girdner, Scott F.; Hambright, David K.; Hamilton, David P.; Havens, Karl; Hessen, Dag O.; Higgins, Scott N.; Huttula, Timo H.; Huuskonen, Hannu; Isles, Peter D. F.; Joehnk, Klaus D.; Jones, Ian D.; Keller, Wendel Bill; Knoll, Lesley B.; Korhonen, Johanna; Kraemer, Benjamin M.; Leavitt, Peter R.; Lepori, Fabio; Luger, Martin S.; Maberly, Stephen C.; Melack, John M.; Melles, Stephanie J.; Müller-Navarra, Dörthe C.; Pierson, Don C.; Pislegina, Helen V.; Plisnier, Pierre-Denis; Richardson, David C.; Rimmer, Alon; Rogora, Michela; Rusak, James A.; Sadro, Steven; Salmaso, Nico; Saros, Jasmine E.; Saulnier-Talbot, Émilie; Schindler, Daniel E.; Schmid, Martin; Shimaraeva, Svetlana V.; Silow, Eugene A.; Sitoki, Lewis M.; Sommaruga, Ruben; Straile, Dietmar; Strock, Kristin E.; Thiery, Wim; Timofeyev, Maxim A.; Verburg, Piet; Vinebrooke, Rolf D.; Weyhenmeyer, Gesa A.; Zadereev, Egor (Rebekah A. Canada, 2020)
    Scientific Reports 10, 1 (2020), 20514
    Globally, lake surface water temperatures have warmed rapidly relative to air temperatures, but changes in deepwater temperatures and vertical thermal structure are still largely unknown. We have compiled the most comprehensive data set to date of long-term (1970–2009) summertime vertical temperature profiles in lakes across the world to examine trends and drivers of whole-lake vertical thermal structure. We found significant increases in surface water temperatures across lakes at an average rate of + 0.37 °C decade−1, comparable to changes reported previously for other lakes, and similarly consistent trends of increasing water column stability (+ 0.08 kg m−3 decade−1). In contrast, however, deepwater temperature trends showed little change on average (+ 0.06 °C decade−1), but had high variability across lakes, with trends in individual lakes ranging from − 0.68 °C decade−1 to + 0.65 °C decade−1. The variability in deepwater temperature trends was not explained by trends in either surface water temperatures or thermal stability within lakes, and only 8.4% was explained by lake thermal region or local lake characteristics in a random forest analysis. These findings suggest that external drivers beyond our tested lake characteristics are important in explaining long-term trends in thermal structure, such as local to regional climate patterns or additional external anthropogenic influences.
  • Broman, Elias; Asmala, Eero; Carstensen, Jacob; Pinhassi, Jarone; Dopson, Mark (2019)
    Coastal zones are important transitional areas between the land and sea, where both terrestrial and phytoplankton supplied dissolved organic matter (DOM) are respired or transformed. As climate change is expected to increase river discharge and water temperatures, DOM from both allochthonous and autochthonous sources is projected to increase. As these transformations are largely regulated by bacteria, we analyzed microbial community structure data in relation to a 6-month long time-series dataset of DOM characteristics from Roskilde Fjord and adjacent streams, Denmark. The results showed that the microbial community composition in the outer estuary (closer to the sea) was largely associated with salinity and nutrients, while the inner estuary formed two clusters linked to either nutrients plus allochthonous DOM or autochthonous DOM characteristics. In contrast, the microbial community composition in the streams was found to be mainly associated with allochthonous DOM characteristics. A general pattern across the land-to-sea interface was that Betaproteobacteria were strongly associated with humic-like DOM [operational taxonomic units (OTUs) belonging to family Comamonadaceae], while distinct populations were instead associated with nutrients or abiotic variables such as temperature (Cyanobacteria genus Synechococcus) and salinity (Actinobacteria family Microbacteriaceae). Furthermore, there was a stark shift in the relative abundance of OTUs between stream and marine stations. This indicates that as DOM travels through the land-to-sea interface, different bacterial guilds continuously degrade it.
  • Luoma, Antti (Helsingin yliopisto, 2018)
    Plantation forestry has increased dramatically in Uruguay during the past 25 years. Thus, planted forests have an increasing importance in providing other ecosystem services in addition to wood provision in landscape scale. Forest sector company UPM owns more than 250 000 hectares of Eucalyptus plantations in Uruguay. UPM seeks to enhance their systems to measure and monitor ecosystem services, to better understand sustainable provision of ecosystem services in their plantation landscapes, and to mitigate negative and maximize positive impacts. Benefits of monitoring and incorporating ecosystem services at management level include strengthened decision-making and communication, license to operate in long-term and better corporate image. Four ecosystem services were selected for analysis based on their relevance in UPM’s corporate strategy: wood provision, climate regulation, water provision and biodiversity maintenance. Provision of the ecosystem services were estimated quantitatively and compared to a pasture land baseline. Provision of ecosystem services was also linked to product level, tonne of pulp, when applicable. Data for the analysis was partly provided by UPM and partly by literature meta-analysis. Climate benefit of converting pasture to Eucalyptus is 8–31 MgC/ha or 29–115 MgCO2/ha depending on species and rotation number. Planting 40% of a micro water-shed with Eucalyptus reduces water streamflow approximately by 20–27%, while reducing streamflow of peak rainfall months by up to 40%, potentially alleviating floods. Pastures in UPM’s landscapes are well connected, but provided little core habitats. Native riparian forests are fragmented and maintain biodiversity poorly. Suggestions for future monitoring and measuring are presented. This thesis works as a waypoint for future studies of holistic ecosystem services provision in UPM assets.
  • Kujansuu, Eila; Kujansuu, Leena; Paassilta, Marita; Mustonen, Jukka; Vaarala, Outi (2019)
    Background The hygiene hypothesis suggests that a decreased microbial load contributes to an increased risk of allergies. In the Finnish municipality of Nokia, sewage water was accidentally mixed with drinking water for 2 days. We studied the association between exposure and the emergence of allergies in children. Methods Children aged 2-5 years living in the accident area and an age-matched cohort from the control municipality were recruited. Based on the questionnaires, we identified 139 children exposed to the contaminated water and selected age- and sex-matched controls for them (mean age 16.59 months at the time of the accident). Allergic symptoms and diseases were recorded by ISAAC questionnaires and skin prick tests (SPTs) performed 2 and 5 years after the accident. Results SPT positivity at 5 years of follow-up was decreased in the children exposed to the sewage water below 1 year of age (OR 0.311, 95% CI 0.118-0.820; P = 0.019), particularly in children who did not develop gastroenteritis at exposure. In contrast, the children over 1 year of age at the exposure tended more likely to be SPT-positive at 5 years of follow-up (OR 1.997, 95% CI 0.963-4.143; P = 0.070). Conclusions Sewage water exposure during the first year of life, but not later, decreased the risk of IgE sensitization emphasizing the importance of age as a modulator. The modulation of IgE sensitization by the presence of clinical gastroenteritis at the exposure suggests that the nature of microbial load may have importance or alternatively shared host defense mechanisms protect from infection and atopic sensitization.
  • Siren, Heli; El Fellah, Sandra (2019)
    Microemulsion gels were synthetized from macadamia, linseed, olive, walnut, rapeseed, sesame, and coconut oils and frying oil made from sunflower, palm, and rapeseed oils. The gels were similar as polyacrylamide-based gels with exception of replacing dodecyl sulfate with vegetable oils. The gels were modified with celluloses, cotton, or lignin to make the emulsions sustainable for water purification. They were used to compare sorption properties when they were used as solid-phase adsorbents in isolation of steroids from water. Hydrophobicity features of the gels were compared by detecting adsorption and extraction efficiency of nonpolar androstenedione, testosterone, and progesterone, which exist in wastewater and drinking water. Quantification was done with partial filling-micellar electrokinetic chromatography with 29.5 mM sodium dodecyl sulfate-3.4 mM sodium taurocholate as the micelle and 20 mM ammonium acetate (pH 9.68) as the electrolyte. UV-detection was used. Methanol was the best eluent for extraction of steroids from gels. The highest recoveries were from frying oil and rapeseed oil gels modified with celluloses. They also possessed the best floating properties on water surface. Lignin modified gels were too hydrophilic, when in touch with water they filled up with water. They also had the lowest capacity.
  • Päivänen, Juhani (Suomen metsätieteellinen seura, 1973)
  • Sivander, Linda (Helsingin yliopisto, 2018)
    This thesis discusses what it means to live with breaking water supply in rural northern Uganda, focusing on boreholes and their governance. The study is based on ethnographic fieldwork consisting of participant observation and interviews conducted mostly in the centre of a rural sub-county in central Acholiland, Uganda, in spring 2015. In development discourse, boreholes are perceived as a viable technology to increase access to safe water in the Global South. However, they are known to have high rates of failure, often seen to lead to their abandonment by the communities who manage them. The thesis argues that this perception has a limited view of borehole failure and uses overtly passive terms to describe the communities. Instead, the study intends to expand the understanding of the ways in which boreholes can fail, and show how borehole users try to cope with and overcome breakage. The main research questions revolve around infrastructural failure and its management: What does it mean when infrastructures break down? How is this breakage experienced, managed and lived? In the 2000s, in anthropology and other disciplines, (non-human) materiality has resurfaced as a significant focus of study. In many of such approaches, assemblage theory has garnered increasing popularity. Assemblage brings together heterogeneous elements, such as people, objects, discourses and events, and includes an understanding of the unexpected elements remaining in the peripheries of networks. Utilizing this framework, the thesis aims to broaden the view of infrastructural breakage, often predominated by a notion of failure as a particular moment, where the infrastructure moves between two categories of functionality. The thesis argues that the breakdown of boreholes is processual, anticipated, and embodied, and a consequence of multiple nonhuman and human factors. This thesis participates in another growing anthropological discussion; vulnerability and its management, often accomplished by seeking relations with others. The thesis shows that the research participants’ lives were penetrated by material and financial precariousness, which is why they hoped for support in borehole maintenance from those more powerful. This has been seen as evidence of their passivity and dependency, which are seen as hindering lasting change in the sustainable development discourse. The study illustrates why hoping for support made sense for the research participants by recounting the socio-historical developments impacting northern Uganda and water governance. It is suggested that instead of perceiving such hopes as passive neglect of responsibility, they can be better understood as active coping strategies, often relating to past NGO projects’ material sustainability. Besides asking for support, the communities and borehole mechanics were embarking upon various other means of navigating borehole failure and sustaining their water points in order to stabilize the assemblage. It is argued that these mechanisms were utilized due to the motivation that “water is life”, which is seen in the thesis alike to desire or wish, the human force capable of bringing relations in assemblages into existence. The thesis shows that the communities’ understanding of water as life as well as their strategies of coping, however, tend to be obscured in many of the descriptions of borehole breakage, which perceive the low sustainability of boreholes to be largely related to social factors. The study illustrates that a focus on the lived reality of breaking water supply reveals the politics surrounding predominant ideas of infrastructural failure; when the processual and cyclical nature of borehole breakage is neglected, the social factors become perceived as the main issues worth tackling to improve sustainability. Yet, for the water users, the boreholes held immense value as the suppliers of vital water, which is why it was crucial to try to maintain them. The thesis thus demonstrates how a more comprehensive focus on breakage and its management can help us to readjust the ways in which we perceive failures, as well as shed light on the politics in their discursive utilizations.
  • 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.
  • Matkala, Laura; Kulmala, Liisa; Kolari, Pasi; Aurela, Mika; Bäck, Jaana (2021)
    We studied the occurrence of extreme weather events and their effects on the carbon dioxide and water exchange of two subarctic forest stands. One study site was a Scots pine site in eastern Finnish Lapland (VarriO), and the other was a Norway spruce site in western Finnish Lapland (Kenttarova). We compared short-term meteorological data with long-term data and found that the pine forest had experienced extremely warm, wet and dry years as well as cold spells during the growing season in the studied period of 2012-2018. The spruce forest was studied during the period 2003-2013, during which time it experienced extremely warm and wet summers, and dry periods, although the dry times were not statistically defined as such. The spruce forest was less resilient to warm and dry periods, as its total ecosystem respiration and respiration potential decreased during warm and dry summers, while the same effect was not seen in the pine forest. The decreased respiration values may have occurred due to slowed decomposition of organic matter. The pine forest experienced two cold spells during the studied period. One of these cold periods was more of a continuation of the previous cold spring and late start of the growing season in 2017, while the other one occurred after a warm period in 2014. The ecosystem respiration rates and gross primary production in 2017 remained low for the whole July-August time period likely due to cold-inhibited growth of ground vegetation, while in 2014 no such effect could be seen. We saw no effect of extreme weather events in the water exchange related measurements in either of the forests. Overall, both forests, especially the trees, were resilient to the weather extremes and experienced no long-term damage.
  • Rapo, Aleksi (Helsingin yliopisto, 2021)
    The geographical origin of food can be determined by analyzing stable isotope ratios of hydrogen and oxygen from water samples that have been extracted from food matrices. A geographical gradient is formed from isotope ratios of water constituents, due to the small mass differences of the different isotopes, which can be also seen in the growing plants in certain regions. Finnish Food Authority has established a method for differentiating domestic and foreign strawberry samples, which uses a database that was created for Finnish strawberries. To produce a representative water sample from food, almost all of the water needs to be extracted from the matrix. The aim of this master’s thesis was to establish and optimize the extraction process of water from strawberry samples with a cryogenic vacuum extraction (CVE). The secondary objective was to test if isotopic values of Finnish strawberries differ from that of foreign strawberry samples and thus be used for determining the domesticity of strawberries. The performance of the cryogenic vacuum extraction procedure was confirmed with three validation tests which tested extraction effect on the sample’s isotope ratios of hydrogen and oxygen, cross-contamination between extraction units and suitable sample fixing materials. The optimization did not reach acceptable accuracy as there were no significant differences between the experimental runs for the Box-Behnken design (BBD). The reason showing ineffective modelling of the design remains unknown, especially as the response surface diagram shows clearly the optimal and minimal trends of the tested factors for δ2H. However, this was not so evident for δ18O. The ranges of tested factors may partly explain this discrepancy. Nonetheless, the differentiation of foreign and domestic strawberry samples was successful with principal component analyses. However, several factors concerning cryogenic vacuum extraction and water extraction in general, such as recovery of water, sample pretreatment, sample storage, different sample matrices and coextracted compounds as well as extraction parameters, need to be addressed in future studies.
  • Salmon, Yann; Li, Xuefei; Yang, Bo; Ma, Keping; Siegwolf, Rolf T. W.; Schmid, Bernhard (2018)
    Increasing biodiversity has been linked to higher primary productivity in terrestrial ecosystems. However, the underlying ecophysiological mechanisms remain poorly understood. We investigated the effects of surrounding species richness (monoculture, two- and four-species mixtures) on the ecophysiology of Lithocarpus glaber seedlings in experimental plots in subtropical China. A natural rain event isotopically labelled both the water uptaken by the L.glaber seedlings and the carbon in new photoassimilates through changes of photosynthetic discrimination. We followed the labelled carbon (C) and oxygen (O) in the plant-soil-atmosphere continuum. We measured gas-exchange variables (C assimilation, transpiration and above- and belowground respiration) and C-13 in leaf biomass, phloem, soil microbial biomass, leaf- and soil-respired CO2 as well as O-18 in leaf and xylem water. The C-13 signal in phloem and respired CO2 in L.glaber in monoculture lagged behind those in species mixture, showing a slower transport of new photoassimilates to and through the phloem in monoculture. Furthermore, leaf-water O-18 enrichment above the xylem water in L.glaber increased after the rain in lower diversity plots suggesting a lower ability to compensate for increased transpiration. Lithocarpus glaber in monoculture showed higher C assimilation rate and water-use efficiency. However, these increased C resources did not translate in higher growth of L.glaber in monoculture suggesting the existence of larger nongrowth-related C sinks in monoculture. These ecophysiological responses of L.glaber, in agreement with current understanding of phloem transport are consistent with a stronger competition for water resources in monoculture than in species mixtures. Therefore, increasing species diversity in the close vicinity of the studied plants appears to alleviate physiological stress induced by water competition and to counterbalance the negative effects of interspecific competition on assimilation rates for L.glaber by allowing a higher fraction of the C assimilated to be allocated to growth in species mixture than in monoculture.
  • Tiensuu, Meeri (Helsingin yliopisto, 2018)
    This is a qualitative case study that contributes to the discussion of political ecology of water in the region where the water resources are scarce. Empirically, the thesis focuses on the meaning of water scarcity around the region of the Sea of Galilee in Israel. To discuss water scarcity around the Sea of Galilee, this thesis examines the concepts of governance, politics of scale, dimensions of water and environmental justice that are part of wider academic discussion of political ecology. This study collects the experiences and perceptions of local farmers from the Sea of Galilee and reflects these with the relevant aspects in current political ecology discussion. The data of the study consist of individual experiences and narratives of water scarcity in the agricultural sector, collected from Israeli farmers. The ethnographic research consisted of 10 interviews, participant observation and document analysis of news articles, NGO-report, Israeli national water plan and OECD-report of Israeli agriculture. The data was analyzed using qualitative thematic analysis tools, against the theoretical framework of political ecology of water. The findings of this study demonstrate that water scarcity is a multi-scalar phenomenon that is both natural and human-made. Water scarcity needs to be examined from various perspectives that are interconnected as well as overlapping. Through analysis, the thesis demonstrates that the role of agriculture had and still has an important meaning for nation-building in Israel. The thesis also demonstrates that water governance is a complex process that includes several actors and where the power structures create dynamic imbalances. Water governance in Israel is shaped by institutions and legal framework, cultural values, historical development, technologies and physical access to water. The result of the thesis adds understanding to the challenges of water scarcity in contemporary world where power asymmetries are constantly present. Conflicts over water and water scarcity are already seen in globalized world and therefore the findings of this thesis opens further dimensions to study water-related challenges in areas where water scarcity is witnessed.
  • Nygren, Anja (2021)
    Water-related disasters have become more unpredictable amidst human-induced climatic and hydroecological changes, with profound effects on people inhabiting fragile river basins. In this article, I analyse drastic waterscape transformations and people's differentiated exposure to water-related vulnerabilities in the Grijalva River lower basin, southeastern Mexico, focusing on how state authority is reinforced through waterscape alterations and how altered waterscapes shape state-making and scalar politics. Examining interlinkages between 1) state-making and governance; 2) resource-making and politics of scale; and 3) hazard-making and the dynamics of socionature, the article contributes to scholarly and development practice discussions on environmental vulnerability. I argue that the goals of consolidating state power and promoting development through massive waterscape changes and resource extractions have provoked hazards that are difficult to control, resulting in differentiated distribution of environmental benefits and burdens. Drawing on archival research, documentary analysis, thematic interviews, and ethnographic fieldwork, the study illustrates the overlapping and cumulative effects of state-making, politics of scale, and the dynamics of socionature on socially differentiated vulnerability. Although the forms of governance shift over time, statecraft as a mode of consolidating state authority and controlling lower basin environments and residents persists. The government prevents social mobilisation through political persuasion and pressure, and disciplines residents to adapt to altered waterscapes, while allowing few changes in prevalent power structures. Simultaneously, the study demonstrates that water cannot be controlled by political rules and requisites, while local residents reinterpret dominant ways of governing through claim-making, negotiation, everyday resistance, and situational improvisation, albeit within unequal power relations. The study enhances understanding of water-related vulnerabilities resulting from recurrent, yet temporally remoulded agendas of state-making combined with socially differentiating politics of scaling and the dynamics of socionature, which altogether reformulate human-nonhuman interactions and make local smallholders and pen-urban poor increasingly vulnerable to floods. (c) 2021 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).