Browsing by Subject "Nutrients"

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  • Niemistö, Juha; Kononets, Mikhail; Ekeroth, Nils; Tallberg, Petra; Tengberg, Anders; Hall, Per O.J. (2018)
    Abstract Benthic fluxes of oxygen and dissolved inorganic nutrients; phosphate (DIP), ammonium (NH4), nitrate + nitrite (NOx), and silicate (DSi); and the effects of resuspension on these were studied in situ with the Göteborg benthic landers in the Gulf of Finland archipelago, Baltic Sea. The benthic fluxes were examined at two shallow stations at depths of 7 m and 20 m in May and August 2014. Resuspension altered benthic fluxes of oxygen and nutrients in most of the experiments in August, but not in May, which was mainly due to weaker resuspension treatments in spring. Additionally, the benthic nutrient regeneration rates were higher and redox conditions lower in August when the water was warmer. In August, resuspension increased the benthic oxygen uptake by 33–35%, which was, in addition to stronger resuspension treatment, attributed to higher amounts of dissolved reduced substances in the sediment pore water in comparison to conditions in May. Adsorption onto newly formed iron oxyhydroxides could explain the uptake of DIP by the sediment at the 20 m station and the lowering of the DSi efflux by 31% at the 7 m station during resuspension in August. In addition, resuspension promoted nitrification, as indicated by increased NOx fluxes at both stations (by 30% and 27% at the 7 m and 20 m station, respectively) and a lowered NH4 flux (by 48%) at the 7 m station. Predicted increases in the magnitude and frequency of resuspension will thus markedly affect the transport of phosphorus and silicon and the cycling of nitrogen in the shallow areas of the Gulf of Finland.
  • Garcia-Larsen, Vanessa; Del Giacco, Stefano R.; Moreira, Andre; Bonini, Matteo; Haahtela, Tari; Bonini, Sergio; Carlsen, Kai-Hakon; Agache, Ioana; Fonseca, Joao; Papadopoulos, Nikolaos G.; Delgado, Luis (2016)
    Background: Diet has been proposed to modulate the risk of asthma in children and adults. An increasing body of epidemiological studies have been published in the last year investigating the association between dietary intake and asthma. As part of the Evidence-Based Clinical Practice Guideline Task Force on 'Lifestyle Interventions in Allergy and Asthma' funded by the European Academy of Allergy and Clinical Immunology, we will use a systematic approach to review the evidence from published scientific literature on dietary intake and asthma in children and adults. Methods: This systematic review will be carried out following the PRISMA guidelines. The protocol has been published in PROSPERO (CRD42016036078). We will review the evidence from epidemiological studies in children (from the age of 2 years) and adults and dietary intake of foods and nutrients. Discussion: The findings from this review will be used as a reference to inform guideline recommendations.
  • Kerminen, Kaisa Aino Maria; Moël, Romain Le; Harju, Anu Vilhelmiina; Kontro, Merja Hannele (2018)
    Pesticides leaching from soil to surface and groundwater are a global threat for drinking water safety, as no cleaning methods occur for groundwater environment. We examined whether peat, compost-peat-sand (CPS) mixture, NH4NO3, NH4NO3 with sodium citrate (Na-citrate), and the surfactant methyl-beta-cyclodextrin additions enhance atrazine, simazine, hexazinone, dichlobenil, and the degradate 2,6-dichlorobenzamide (BAM) dissipations in sediment slurries under aerobic and anaerobic conditions, with sterilized controls. The vadose zone sediment cores were drilled from a depth of 11.3-14.6m in an herbicide-contaminated groundwater area. The peat and CPS enhanced chemical atrazine and simazine dissipation, and the peat enhanced chemical hexazinone dissipation, all oxygen-independently. Dichlobenil dissipated under all conditions, while BAM dissipation was fairly slow and half-lives could not be calculated. The chemical dissipation rates could be associated with the chemical structures and properties of the herbicides, and additive compositions, not with pH. Microbial atrazine degradation was only observed in the Pseudomonas sp. ADP amended slurries, although the sediment slurries were known to contain atrazine-degrading microorganisms. The bioavailability of atrazine in the water phase seemed to be limited, which could be due to complex formation with organic and inorganic colloids. Atrazine degradation by indigenous microbes could not be stimulated by the surfactant methyl-beta-cyclodextrin, or by the additives NH4NO3 and NH4NO3 with Na-citrate, although the nitrogen additives increased microbial growth. (C) 2017 Elsevier B.V. All rights reserved.
  • Tuokkola, Jetta; Luukkainen, Päivi; Kaila, Minna; Takkinen, Hanna-Mari; Niinisto, Sari; Veijola, Riitta; Virta, Lauri J.; Knip, Mikael; Simell, Olli; Ilonen, Jorma; Virtanen, Suvi M. (2016)
    Maternal nutrient intake during pregnancy and lactation potentially influences the development of allergic diseases. Cows' milk allergy (CMA) is often the first manifestation of atopic diseases, but the impact of early nutritional influences on CMA has not been explored. The associations between maternal intakes of folate, folic acid and vitamin D during pregnancy and lactation were addressed in a prospective, population-based birth cohort within the Finnish Type 1 Diabetes Prediction and Prevention Study. Mothers of 4921 children during pregnancy and 2940 children during lactation provided information on maternal dietary intake during the 8th month of pregnancy and the 3rd month of lactation using a detailed, validated FFQ. Information on diagnosed CMA in the offspring was obtained from a medical registry as well as queried from the parents. The Finnish food composition database was used to calculate nutrient intake. Logistic regression was applied for statistical analyses. Folate intake and folic acid and vitamin D supplement use were associated with an increased risk of CMA in the offspring, whereas vitamin D intake from foods during pregnancy was associated with a decreased risk of CMA. Thus, maternal nutrient intake during pregnancy and lactation may affect the development of CMA in offspring. Supplementation with folic acid may not be beneficial in terms of CMA development, especially in children of allergic mothers. The association between dietary supplement use and CMA risk can at least partly be explained by increased health-seeking behaviour among more educated mothers who also use more dietary supplements.
  • Kilpeläinen, Jouni; Barbero-López, Aitor; Adamczyk, Bartosz Wojciech; Aphalo, Pedro J.; Lehto, Tarja (2019)
    Background and aims The aim was to assess possible benefits or drawbacks of arbuscular-mycorrhizal (AM) and ectomycorrhizal (EM) colonisation compared to no mycorrhizas (NM) in seedlings of the same host species. Eight broadleaf species were tested for mycorrhiza formation. Grey alder (Alnus incana) and four fungal species were selected for further experiments. Methods Grey alder seedlings were inoculated with AM fungi Rhizophagus intraradices and Glomus hoi or EM fungi Paxillus involutus plus an ascomycete isolated from Alnus roots or mock-inoculated (NM). Results EM formed in 70% of root tips and AM in 30% of root length. AM plants were smaller than EM and NM, but their specific root length (SRL) and specific leaf area (SLA) were highest. Net photosynthesis, stomatal conductance and shoot water potential did not differ between treatments. Foliar Ca, K, Mg, Mn, N, P and S concentrations (mg g−1) were highest in AM plants. However, total foliar contents (mg per plant) were lowest in AM plants, except for P, K and Zn. Conclusions The larger SRL and SLA suggest more efficient resource usage in AM plants, even though these were smaller than EM and NM plants. Grey alder is proposed as a new model species for comparisons between mycorrhiza types in cold climates.
  • Koppelmäki, Kari; Helenius, Juha; Schulte, Rogier (2021)
    Although a circular economy promotes economic and environmental benefits, knowledge gaps remain surrounding the application of these concepts to food systems. A better understanding of the connection between different flows of biomass and energy at different spatial scales is needed to facilitate effective transitions towards circular bioeconomies. This study provides a framework for assessing the circularity of food systems, which we exemplify by identifying key steps towards circularity for three contrasting farming regions in Finland. For each of the regions, we quantified the flows of biomass, nutrients and energy. We found large differences in circularity, depending on the chosen indicator. Most biomass and nutrient flows were related to livestock production, which implies that it plays a key role in circular food systems. Current livestock production was found to be connected to national and global food systems through the international feed trade. This trade generates imbalanced nutrient flows between regions and countries, resulting in excess accumulations of nutrients in regions with net imports. In terms of circularity in energy systems, we found that substantial amounts of energy could be produced from manure and plant-based biomasses without causing food-fuel competition in land use. We also observed that, the inclusion of human excreta would further improve recycling but this was significant only in the region with a high population density. Thus, in this study, we propose a concept of nested circularity in which nutrient, biomass and energy cycles are connected and closed across multiple spatial scales.
  • Karcher, Denis B.; Roth, Florian; Carvalho, Susana; El-Khaled, Yusuf C.; Tilstra, Arjen; Kürten, Benjamin; Struck, Ulrich; Jones, Burton H.; Wild, Christian (2020)
    While various sources increasingly release nutrients to the Red Sea, knowledge about their effects on benthic coral reef communities is scarce. Here, we provide the first comparative assessment of the response of all major benthic groups (hard and soft corals, turf algae and reef sands-together accounting for 80% of the benthic reef community) to in-situ eutrophication in a central Red Sea coral reef. For 8 weeks, dissolved inorganic nitrogen (DIN) concentrations were experimentally increased 3-fold above environmental background concentrations around natural benthic reef communities using a slow release fertilizer with 15% total nitrogen (N) content. We investigated which major functional groups took up the available N, and how this changed organic carbon (C-org) and N contents using elemental and stable isotope measurements. Findings revealed that hard corals (in their tissue), soft corals and turf algae incorporated fertilizer N as indicated by significant increases in delta N-15 by 8%, 27% and 28%, respectively. Among the investigated groups, C-org content significantly increased in sediments (+24%) and in turf algae (+33%). Altogether, this suggests that among the benthic organisms only turf algae were limited by N availability and thus benefited most from N addition. Thereby, based on higher C-org content, turf algae potentially gained competitive advantage over, for example, hard corals. Local management should, thus, particularly address DIN eutrophication by coastal development and consider the role of turf algae as potential bioindicator for eutrophication.
  • ARIA Grp; the ARIA group; Bousquet, Jean; Cristol, Jean-Paul; Czarlewski, Wienczyslawa; Haahtela, Tari; Erhola, Marina; Koskinen, Seppo; Kuitunen, Mikael; Strandberg, Timo; Toppila-Salmi, Sanna; Von Hertzen, Leena (2020)
    There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity.
  • Kilpeläinen, Jouni; Aphalo, Pedro J.; Lehto, Tarja (2020)
    Arbuscular mycorrhizal (AM) plants and fungi associate with lower soil organic matter, higher pH, lower phosphorus and higher nitrogen than ectomycorrhizal (EM) ones. However, soil conditions correlate with climatic factors, and we suggest that temperature and humidity have also direct roles in the success of mycorrhiza types. The hypothesis here is that EM perform better at low temperatures than AM, and AM resist drought better than EM. Narrowleaf cottonwood (Populus angustifolia E. James) forms both AM and EM. We grew seedlings in soil at 14, 20 and 26 °C in factorial combinations with adequate watering and a cyclic mild drought for 4 and 7 weeks. As hypothesized, the percent of EM root tips was largest at 14 °C, while the proportional root length with AM was largest at the two higher temperatures. However, unlike expectations, drought increased EM formation slightly, while the AM colonization was lower in the dry treatment. Plant growth was reduced more by low temperature than drought. Root branching was more prominent at low temperature and root length and mass growth at higher temperatures. Soil nutrient availability did not provide a direct explanation to the results, as both soluble soil N and P were the same in 14 and 20 °C, while the change in mycorrhiza colonization took place between these temperatures. Differences in root morphology (root branching vs length) may affect the proportions of the mycorrhiza types at different temperature regimes. The most likely explanation to the differential colonization is that temperature affects AM and EM fungi in a different way. In nature, temperature and humidity regimes are tightly correlated, and temperature as such may be a stronger determinant for the success of mycorrhiza types than has been previously considered. The poorer performance of AM in low-temperature and drought conditions may reflect stress avoidance rather than stress tolerance by AM fungi.
  • Joensuu, Mari; Pilditch, Conrad A.; Norkko, Alf (2020)
    Sediment resuspension may play a major role in sediment-water exchange of nutrients, matter and energy in coastal areas where waves and currents dominate sediment transport. Biogeochemical sediment properties regulate sediment erodibility, but there is only limited knowledge of how temporal variability in environmental variables is reflected in the resuspension potential, especially for subtidal habitats. Further, the significance of resuspension on nutrient fluxes in coastal environments has remained unclear as contradicting results have been reported. Here we quantified the temporal variation in resuspension potential metrics (erosion threshold (τc; N m−2) and erosion constant (me; g N−1 s−1)) and associated nutrient fluxes from three sites in the Hanko archipelago (Finland) using a core-based erosion device (EROMES). The sites were sampled bi-monthly from April to December. We also quantified the temporal variation in biogeochemical sediment properties at each site. The τc exhibited the clearest temporal pattern in muddy sediment, where the coefficient of variation (= 67) was two to three times higher than the mixed (= 29) and sandy (= 16) sediments. Dry bulk density was the best predictor for sediment erodibility at all sites explaining 26–46% of the temporal variation in τc despite its limited variability at sandier sites. In addition, temporal variations in the macrofaunal community were important predictors of muddy sediment erodibility and therefore community dynamics need to be considered in sediment transport studies. All sites were potential nutrient sources, yet the overall role of sediment resuspension on nutrient release from the sediments was small.