Browsing by Subject "nutrient"

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  • Kastovska, Eva; Strakova, Petra; Edwards, Keith; Urbanova, Zuzana; Barta, Jiri; Mastny, Jiri; Santruckova, Hana; Picek, Tomas (2018)
    Peatlands are large repositories of carbon (C). Sphagnum mosses play a key role in C sequestration, whereas the presence of vascular plants is generally thought to stimulate peat decomposition. Recent studies stress the importance of plant species for peat quality and soil microbial activity. Thus, learning about specific plant-microbe-soil relations and their potential feedbacks for C and nutrient cycling are important for a correct understanding of C sequestration in peatlands and its potential shift associated with vegetation change. We studied how the long-term presence of blueberry and cotton-grass, the main vascular dominants of spruce swamp forests, is reflected in the peat characteristics, soil microbial biomass and activities, and the possible implications of their spread for nutrient cycling and C storage in these systems. We showed that the potential effect of vascular plants on ecosystem functioning is species specific and need not necessarily result in increased organic matter decomposition. Although the presence of blueberry enhanced phosphorus availability, soil microbial biomass and the activities of C-acquiring enzymes, cotton-grass strongly depleted phosphorus and nitrogen from the peat. The harsh conditions and prevailing anoxia retarded the decomposition of cotton-grass litter and caused no significant enhancement in microbial biomass and exoenzymatic activity. Therefore, the spread of blueberry in peatlands may stimulate organic matter decomposition and negatively affect the C sequestration process, whereas the potential spread of cotton-grass would not likely change the functioning of peatlands as C sinks.
  • Tan, Xiao; Alen, Markku; Wang, Kun; Tenhunen, Jarkko; Wiklund, Petri; Partinen, Markku; Cheng, Sulin (2016)
    Growing evidence suggests that diet alteration affects sleep, but this has not yet been studied in adults with insomnia symptoms. We aimed to determine the effect of a six-month diet intervention on sleep among overweight and obese (Body mass index, BMI >= 25 kg/m(2)) men with chronic insomnia symptoms. Forty-nine men aged 30-65 years with chronic insomnia symptoms were randomized into diet (n = 28) or control (n = 21) groups. The diet group underwent a six-month individualized diet intervention with three face-to-face counseling sessions and online supervision 1-3 times per week; 300-500 kcal/day less energy intake and optimized nutrient composition were recommended. Controls were instructed to maintain their habitual lifestyle. Sleep parameters were determined by piezoelectric bed sensors, a sleep diary, and a Basic Nordic sleep questionnaire. Compared to the controls, the diet group had shorter objective sleep onset latency after intervention. Within the diet group, prolonged objective total sleep time, improved objective sleep efficiency, lower depression score, less subjective nocturnal awakenings, and nocturia were found after intervention. In conclusion, modest energy restriction and optimized nutrient composition shorten sleep onset latency in overweight and obese men with insomnia symptoms.
  • Christensen, Tue; Nielsen, Cecilie Wirenfeldt; Valsta, Liisa; Aalto, Sanni; Haario, Peppi; Reinivuo, Heli; Virtanen, Suvi; Pastell, Helena; Nieminen, Janne; Reykdal, Ólafur; Axelsson, Cecilia; Petrelius-Sipinen, Jessica; Kielland, Ellen; Østerholt Dalane, Jorån; Hauger Carlsen, Monica; Salupuu, Kristin; Jõgi, Änn (Nordic Council of Ministers, 2020)
    This report describes the activities of two projects that were carried out using the infrastructure of the Nordic Food Analysis Network, i.e. the ‘Nordic Food Composition Data for Labelling (NordCoLa)’ project carried out between 2018 and 2020, and the preceding project ‘Fostering the quality and use of Nordic food composition data’, carried out under the Finnish Presidency of the NCM in 2016. The primary aim of the NordCoLa project was to evaluate the needs, synergies and critical points of the Nordic FCDBs (e.g. food ingredient and nutrient value gaps) in relation to the composition data to be used to implement the new European nutrient labelling legislation. This was to ensure quality food composition data in the Nordic countries for food producers and other users for nutrient labelling purposes. The most important gaps were evaluated and summarised by this project. This project included an exercise comparing calculated and analysed nutrient information of selected Nordic food samples. This information was then compared with the acceptable tolerance limits in use in the EU. As part of the projects, two open seminars were organised in Helsinki; the first one on 16 October 2016 and the second on 17 April 2019. The seminars gathered a total of around 150 participants together to hear about challenges in the area of food composition data and their use in food labelling and related quality issues. In addition, the project included research on food label information in order to evaluate the usefulness of the Mintel Global New Products’ Database (Mintel GNPD) and GS1 in the work of updating and compiling information used in food composition databases. The network’s main conclusions and strategical proposals are as follows: • There is a need for more analyses and continuous compiling work in order to ensure updated FCDBs for the users. Opportunities for Nordic collaboration in food analyses should be carefully evaluated. • More industrial ingredients need to be analysed and added to FCDBs. Obtaining such information is important to keep the databases useful, especially for SMEs in the food business. • The calculated values are of overall good quality when compared with analysed values, with the exception of protein, sugars and salt. This warrants more attention to take carbohydrates and especially simple sugars into account when planning future national food analysis programmes. Collecting more information on salt content and comparing it with the analysed information on food products is also needed. • There is no legislation for the methods to be used in the food analysis. This means that different methods are used and even different components may be measured resulting variation in nutrient contents. Sugars are an example of that, since different techniques measure total sugar content or different 7 sugar components separately and both ways are accepted for labelling purposes. • Calculating nutrient contents of food items according to a standardised method is a good and affordable way of producing values for food composition databases and food labelling purposes, if the data quality of the FCDBs are based on analysed values. • The acceptable variation in nutrient label information based on EC legislation tolerances is very large. The tolerances may even threaten the meaningful reformulation of food products and reliable consumer information due to uncertainties over the labelled nutrient values. • More information is needed regarding the validity of nutrient labelling at the Nordic and European level. To avoid misleading consumer information, food analyses should be used to check the validity of nutrient labelling and to monitor reformulation efforts. • Nutrient label data from commercial food label databases, for example, is not recommended to be used, in general, for updating nutrient values of foods in the national FCDBs. However, such databases were found to be partially useful in updating the coverage, i.e. food lists of national FCDBs, if the used databases cover most of the national market. • Nordic collaboration should be further intensified in the fields of analysing nutrient content of missing ingredients in FCDBs, harmonising nutrient label calculation procedures and proposing improvements to the European legislation concerning tolerances of nutrient values in labelling.
  • Humalisto, Niko; Valve, Helena; Åkerman, Maria (Taylor & Francis, 2021)
    Environmental Politics, 30:5, 833-853
    The circular economy (CE) is currently generating considerable expectations. The concept describes an aspired future but does not provide clear guidance for policy-making. As policy outcomes often rest on initiatives generated in a bottom-up fashion, our attention must be directed to the ways policies are made accessible and interesting to those who might take the initiative. We claim that on-line publicity plays a key role in this. Our findings from a hyperlink analysis focusing on a government funding call for nutrient recycling in Finland show how multiple versions of the policy topic unfold online, as emergent hyperlink clusters prioritize specific agents, material circuits, and policy visions over others. The topic becomes connected with activities and agendas to create path dependencies and to strengthen existing divisions rather than to advocate change. Thus, we argue that CE policy design must recognize the way policy is shaped through online publicity creation.
  • Brady, Mark V.; Andersen, Mikael Skou; Andersson, Anna; Kilis, Emils; Saarela, Sanna-Riikka; Hvarregaard Thorsøe, Martin (Royal Swedish Academy of Sciences, 2022)
    In this perspective article, we provide recommendations for strengthening the policy framework for protecting the Baltic Sea from agricultural nutrient pollution. The most striking weakness is the lax implementation of prescribed abatement measures, particularly concerning manure management, in most countries. Institutions of the EU should also be leveraged for achieving Baltic Sea Action Plan (BSAP) goals. In contrast to the Helsinki Convention, the European Union has economic, political and legal mandates to further implementation and compliance. Equally important is the need for strengthening of local institutions, particularly Water Boards and independent agricultural advisory services in the eastern Baltic Sea Region countries. There is also an urgent need for implementation of voluntary land-use measures where EU funding available to farmers is more broadly and effectively used by providing it on the basis of estimated abatement performance, which can be realized through modelling. The enormous potential for funding performance-based schemes, manure management infrastructure and advisory services through the EU’s Common Agricultural Policy are currently underutilized.
  • Kaarlejarvi, Elina; Salemaa, Maija; Tonteri, Tiina; Merila, Paivi; Laine, Anna-Liisa (2021)
    Aim The diversity and composition of natural communities are rapidly changing due to anthropogenic disturbances. Magnitude of this compositional reorganization varies across the globe, but reasons behind the variation remain largely unknown. Disturbances induce temporal turnover by stimulating species colonizations, causing local extinctions, altering dominance structure, or all of these. We test which of these processes drive temporal community changes, and whether they are constrained by natural environmental gradients. Moreover, we assess to what degree identity shifts translate to changes in dominance structure. Location Finland. Time period Observations 1985-2006, disturbance history > 140 years. Major taxa studied Vascular plants. Methods We investigated temporal turnover of boreal forest understorey in response to disturbance, here forest management, along a soil fertility gradient. We disentangle the roles of species gains, losses and abundance changes in driving temporal turnover in response to and after disturbance by comparing turnover rates in different forest age categories along a fertility gradient. We quantify temporal turnover using richness-based complement of Jaccard's similarity index and proportional-abundance based dissimilarity index. We also test whether disturbance history or fertility influence the relationship between identity shifts and dominance structure. Results We found that the impact of disturbance on temporal turnover depends on soil fertility. The greatest turnover occurred in the most fertile forests immediately after disturbance. There, species gains and losses strongly altered dominance structure leading to high turnover, whereas undisturbed old forests and nutrient-poor habitats were characterized by stable dominant species even when the majority of species shifted their identity. Main conclusions Our results suggest that human impacts on temporal biodiversity change vary along environmental gradients. In boreal forests, the fertile habitats have a higher probability than nutrient-poor sites of changing their composition in response to anthropogenic disturbances. Resource availability and disturbance history may thus influence consequences of temporal turnover for ecosystem functioning.
  • Saarman, Pauliina (Helsingin yliopisto, 2020)
    Iron is a trace element but indispensable for all photosynthesizing organisms. It is unevenly distributed in the world’s oceans, limiting production in offshore high nitrogen low chlorophyll (HNLC) seas. The Caribbean Sea periodically receives high amounts of iron-carrying aeolian dust originating in the African desert. This aerosol Fe is estimated to contribute three times as much as riverine input to the total iron in the seawater, a considerable fraction of it being soluble ferrous Fe(II) due to photochemical reactions. It has been hypothesized that the excess iron in the Caribbean Sea is one of the reasons why the Caribbean coral reefs are less resilient to degradation. The algae that are not limited by iron have the potential to efficiently utilize the macronutrients from e.g. anthropogenic sources and overgrow the corals. In this study Fe, N & P enrichment experiments were conducted in situ in Guadeloupe to find out if iron limitation can be detected and to contemplate the role of atmospheric iron and the anthropogenic impact. Sargassum polyceratium and Dictyota spp. (Phaeophyceae) were collected from four locations that had degraded coral reefs with macroalgae growing on them. The samples’ fluorescence was measured using Pulse Amplitude Modulator (PAM) fluoroscope to detect nutrient-induced fluorescence transients (NIFTs), rapid changes in chlorophyll fluorescence caused by nutrient assimilation in the algal specimen. Iron limitation was detected in all of the study locations but it was weak, which gives limited support to the hypothesis about iron deteriorating the Caribbean reefs’ chances against disturbance. Comparison of the locations did not result in differences in iron limitation according to the anthropogenic impact level. The difference was statistically significant in P limitation, the algae from high impact sites expressing greater demand. Ammonium and nitrate enrichments did not result in significant differences, but NH4 limitation did occur, as well as co-limitation of N & P. Iron has an important role in the phosphorus flux in the sediments and high Fe availability benefits N-fixing cyanobacteria. Redox conditions in the sediment control both Fe and P availability in the water column. Nutrient leaching does affect the local nutrient dynamics but the effects of eutrophication depend on both the species and the community. Notable differences in the NIFT responses were detected between the species that may indeed exert differing nutritional strategies. Coral reef ecosystem complexity emphasizes the importance of timing as well as consistence in quantification of the environmental parameters. The applicability of NIFT results would improve if they were combined with nutrient concentrations data. The fluorescence method appears to be useful in studying iron limitation but more research on iron-induced NIFTs is needed.