NIVA Open Access Archive
Not a member yet
8416 research outputs found
Sort by
Geochemical Markers as a Tool for the Characterization of a Multi-Layer Urban Aquifer: The Case Study of Como (Northern Italy)
Get PDFThe analysis of geochemical markers is a known valid tool to explore the water sources and understand the main factors affecting natural water quality, which are known issues of interest in environmental science. This study reports the application of geochemical markers to characterize and understand the recharge areas of the multi-layer urban aquifer of Como city (northern Italy). This area presents a perfect case study to test geochemical markers: The hydrogeological setting is affected by a layered karst and fractured aquifer in bedrock, a phreatic aquifer hosted in Holocene sediments and connected with a large freshwater body (Lake Como); the aquifers recharge areas and the water geochemistry are unknown; the possible effect of the tectonic setting on water flow was overlooked. In total, 37 water samples were collected including water from two stacked aquifers and surface water to characterize hydrochemical features. Moreover, six sediment samples in the recent palustrine deposits of the Como subsurface were collected from cores and analyzed to understand the main geochemistry and mineralogy of the hosting material. The chemical analyses of water allow to observe a remarkable difference between the shallow and deep aquifers of the study area, highlighting different recharge areas, as well as a different permanence time in the aquifers. The sediment geochemistry, moreover, confirms the differences in trace elements derived from sediment-water interaction in the aquifers. Finally, an anomalous concentration of As in the Como deep aquifer was observed, suggesting the need of more detailed analyses to understand the origin of this element in water. This study confirms the potentials of geochemical markers to characterize main factors affecting natural water quality, as well as a tool for the reconstruction of recharge areas.publishedVersio
Undersøkelse av hydrografiske og biologiske forhold i Indre Oslofjord Årsrapport 2021
Get PDFProsjektleder/Hovedforfatter André StaalstrømVannkvaliteten er moderat på alle målestasjonene i Indre Oslofjord, inkludert Drøbaksundet. Det var dypvannsfornyelse i Bunnefjorden i 2021, kun litt over to år etter forrige dypvannsfornyelse. NFR sitt nye dypvannsutslipp i Bunnefjorden har gitt signifikant mer vertikal omrøring, som sannsynligvis var medvirkende til at dypvannet ble fornyet tidligere enn forventet. Drøbakjetéen har en positiv virkning på den vertikale omrøringen i fjorden og må bevares. I november 2021 ble det observert den største planteplanktonoppblomstringen i Oslofjorden på flere tiår.publishedVersio
Global estimates of the extent and production of macroalgal forests
Get PDFMacroalgal habitats are believed to be the most extensive and productive of all coastal vegetated ecosystems. In stark contrast to the growing attention on their contribution to carbon export and sequestration, understanding of their global extent and production is limited and these have remained poorly assessed for decades. Here we report a first data-driven assessment of the global extent and production of macroalgal habitats based on modelled and observed distributions and net primary production (NPP) across habitat types. Here we apply a comprehensive niche model to generate an improved global map of potential macroalgal distribution, constrained by incident light on the seafloor and substrate type. We compiled areal net primary production (NPP) rates across macroalgal habitats from the literature and combined this with our estimates of the global extent of these habitats to calculate global macroalgal NPP. We show that macroalgal forests are a major biome with a global area of 6.06–7.22 million km2, dominated by red algae, and NPP of 1.32 Pg C/year, dominated by brown algae. The global macroalgal biome is comparable, in area and NPP, to the Amazon forest, but is globally distributed as a thin strip around shorelines. Macroalgae are expanding in polar, subpolar and tropical areas, where their potential extent is also largest, likely increasing the overall contribution of algal forests to global carbon sequestration.publishedVersio
Effects of waterlogging and elevated salinity on the allocation of photosynthetic carbon in estuarine tidal marsh: a mesocosm experiment
Get PDFEmbargo until September 10, 2023Background and aim Coastal marshes and wetlands hosting blue carbon ecosystems have shown vulnerability to sea-level rise (SLR) and its consequent effects. In this study, we explored the effects of waterlogging and elevated salinity on the accumulation and allocation of photosynthetic carbon (C) in a widely distributed species in marsh lands. Methods The plant–soil mesocosms of Phragmites australis were grown under waterlogging and elevated salinity conditions to investigate the responses of photosynthetic C allocation in different C pools (plant organs and soils) based on 13CO2 pulse-labeling technology. Results Both waterlogging and elevated salinity treatments decreased photosynthetic C fixation. The hydrological treatments also reduced 13C transport to the plant organs of P. australis while significantly increased 13C allocation percentage in roots. Waterlogging and low salinity had no significant effects on 13C allocation to rhizosphere soils, while high salinity (15 and 30 ppt) significantly reduced 13C allocation to soils, indicating a decreased root C export in saline environments. Waterlogging enhanced the effects of salinity on the 13C allocation pattern, particularly during the late growing season. The responses of flooding and elevated salinity on C allocation in plant organs and rhizosphere soils can be related to changes in nutrient, ionic concentrations and microbial biomass. Conclusion The adaptation strategy of P. australis led to increased C allocation in belowground organs under changed hydrology. Expected global SLR projection might decrease total C stocks in P. australis and alter the C allocation pattern in marsh plant-soil systems, due to amplified effects of flooding and elevated salinities.acceptedVersio
Forprosjekt for modellering av Oslofjorden – vurdering av aktuelle modeller
Get PDFProsjektleder Helene FrigstadDenne rapporten gir en vurdering av aktuelle modeller og anbefalinger for å utføre en modellering av Oslofjorden.MiljødirektoratetpublishedVersio
A review of quantitative structure-activity relationship modelling approaches to predict the toxicity of mixtures
Get PDFExposure to chemicals generally occurs in the form of mixtures. However, the great majority of the toxicity data, upon which chemical safety decisions are based, relate only to single compounds. It is currently unfeasible to test a fully representative proportion of mixtures for potential harmful effects and, as such, in silico modelling provides a practical solution to inform safety assessment. Traditional methodologies for deriving estimations of mixture effects, exemplified by principles such as concentration addition (CA) and independent action (IA), are limited as regards the scope of chemical combinations to which they can reliably be applied. Development of appropriate quantitative structure-activity relationships (QSARs) has been put forward as a solution to the shortcomings present within these techniques – allowing for the potential formulation of versatile predictive tools capable of capturing the activities of a full contingent of possible mixtures. This review addresses the current state-of-the-art as regards application of QSAR towards mixture toxicity, discussing the challenges inherent in the task, whilst considering the strengths and limitations of existing approaches. Forty studies are examined within – through reference to several characteristic elements including the nature of the chemicals and endpoints modelled, the form of descriptors adopted, and the principles behind the statistical techniques employed. Recommendations are in turn provided for practices which may assist in further advancing the field, most notably with regards to ensuring confidence in the acquired predictions.publishedVersio
ECORISK2050: An Innovative Training Network for predicting the effects of global change on the emission, fate, effects, and risks of chemicals in aquatic ecosystems
Get PDFBy 2050, the global population is predicted to reach nine billion, with almost three quarters living in cities. The road to 2050 will be marked by changes in land use, climate, and the management of water and food across the world. These global changes (GCs) will likely affect the emissions, transport, and fate of chemicals, and thus the exposure of the natural environment to chemicals.
ECORISK2050 is a Marie Skłodowska-Curie Innovative Training Network that brings together an interdisciplinary consortium of academic, industry and governmental partners to deliver a new generation of scientists, with the skills required to study and manage the effects of GCs on chemical risks to the aquatic environment. The research and training goals are to: (1) assess how inputs and behaviour of chemicals from agriculture and urban environments are affected by different environmental conditions, and how different GC scenarios will drive changes in chemical risks to human and ecosystem health; (2) identify short-to-medium term adaptation and mitigation strategies, to abate unacceptable increases to risks, and (3) develop tools for use by industry and policymakers for the assessment and management of the impacts of GC-related drivers on chemical risks.
This project will deliver the next generation of scientists, consultants, and industry and governmental decision-makers who have the knowledge and skillsets required to address the changing pressures associated with chemicals emitted by agricultural and urban activities, on aquatic systems on the path to 2050 and beyond.publishedVersio
Contributions of marine area-based management tools to the UN sustainable development goals
Get PDFEmbargp until 29 November 2023.Area-Based Management Tools (ABMTs) are spatial instruments for conservation and managing different forms of ocean use. A multitude of ABMTs exists in marine areas within and beyond national jurisdiction, ranging from tools for the regulation of specific human activities (e.g. fisheries, shipping, or mining) to cross-sectoral tools (e.g. such as marine protected areas, MPAs, and marine spatial planning, MSP). By applying expert elicitation and reviewing scientific and grey literature we evaluate the contribution of ABMTs to sustainable development goals (SDGs) as set out under the United Nations 2030 Agenda for Sustainable Development, including for SDG 14 that directly addresses the conservation and sustainable use of oceans, seas, and marine resources. We find that fisheries-related and conservation-related ABMTs, and MSP offer the greatest potential contributions to SDG 14 and to SDGs in general. Moreover, there is high complementarity and synergy among different ABMTs for most SDG 14 targets and other SDGs, with the exception of SDG target 14.6 Prohibit fisheries subsidies and SDG 7 Affordable and clean energy. We find that some ABMTs contribute directly to goal attainment, while others contribute in more nuanced or even unexpected ways. Furthermore, context-specific factors that relate to political and legal factors, enforceability, transparency, governance structure, and inclusivity are crucial for unlocking the full potential of ABMTs of attaining multiple SDGs, as shown through examples. The major challenge to face in the next decade is ensuring durable and equitable outcomes from ABMT implementation by coordinating ABMT initiatives established by different organisations and responsible authorities. It is also critical that outcomes are monitored and evaluated across environmental, social, economic, governance, and health dimensions, with indicators addressing management effectiveness and not only ABMT area coverage.publishedVersio
Line ferries and cargo ships for the monitoring of marine contaminants of emerging concern: Application along a Europe-Arctic transect
Get PDFEmbargo until September 17, 2023Contaminants of emerging concern (CEC) are a focus in marine protection. Several CECs are released with wastewater effluents to coastal environments and their offshore occurrence has been recently documented. Routine monitoring is key for implementing marine protection acts, however infrastructural, financial, and technical limitations hinder this task along broad spatial transects. Here we show the efficacy of a new infrastructure enabling unmanned sampling of surface water from ships of opportunity in providing reliable and cost-effective routine monitoring of CECs along a Europe-Arctic transect. The distribution and long-range transport of several pharmaceuticals and personal care products, artificial food additives, and stimulants were assessed. Validation of operations through strict procedural and analytical quality criteria is presented. A framework to estimate a compound-specific spatial range (SR) index of marine long-range transport based on monitoring results and information on source spatial distribution, is introduced. Estimated SR values ranged 50–350 km depending on compound, yielding a ranking of long-range transport potential which reflected expectations based on degradation half-lives. SR values were used to calculate prior maps of detection probability that can be used to plan future routine monitoring in the region.acceptedVersio
Monitoring of plastic debris in the lower Citarum River using Unmanned Aerial Vehicles (UAVs)
Get PDFPlastic pollution has become a problem in recent years. Various methods are used to reduce and prevent plastic pollution. Many methods have been used to estimate the abundance and transportation of plastics in waters, especially rivers. This paper presents the use of an Unmanned Aerial Vehicle (UAV) to observe plastic waste in river flow. Monitoring plastic debris was conducted at the downstream part of the Citarum river in the Muara Gembong sub-district, Bekasi Regency, West Java Province, on March 6, 8, and 10, 2021. The type of drone used was the DJI Phantom 3 Pro. Data analysis uses the CVAT program developed by Intel to label images. The results show differences between visual counting and UAV, visual counting has a higher value than UAV, but VC might suffer from an observer bias. The counting bias is dependent on the current and the ability of the eye. On the other hand, the results of aerial surveys during the calculation process can be reinterpreted manually or automatically and corrected again. Monitoring plastic debris using UAVs can be an alternative to observing the plastic transportation process in rivers, especially in areas that are difficult to access.publishedVersio