Organic nitrogen steadily increasing in Norwegian rivers draining to the Skagerrak coast

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A carbon balance of Norway: terrestrial and aquatic carbon fluxes

Northernlandscapes accumulate carbon in vegetation and soils while rivers transport significant amounts of land-derived carbon to coastal areas. Here, we quantify carbon sources and sinks in main ecosystems (forests, peatlands, mountains, agricultural areas, lakes) in Norway for 1990–2008, and compare riverine carbon transport with terrestrial carbon accumulation in Norway’s four major discharge areas. Mean annual carbon accumulation (6.0 ± 0.9 Tg C; 19 g C m−2) in terrestrial ecosystems balanced 40 % of national greenhouse gas emissions. The area-normalized terrestrial sink strength declined in the following order (in g C m−2 year−1): tree biomass (40 ± 3) > peatlands (19 ± 15) > forest soils (9 ± 1) ≫ lakes (2 ± 1) > mountains (0.5 ± 0.3), while agricultural soils were sources of carbon (−36 ± 74). The most precise estimate in the carbon balance was for tree biomass, because of the underlying forest inventory data. Poor data on land management and soil type in agricultural soils, and on (former) drainage and peatland type resulted in high uncertainty in carbon loss and uptake estimates in agricultural soils and peatlands, which impacted the uncertainty in total terrestrial carbon accumulation. Also, carbon losses from disturbance in organic soil types were poorly constrained. Riverine coastal inputs of land-derived organic carbon (OC) were 1.0 ± 0.1 Tg C year−1 (3.0 g C m−2 year−1), with highest area-specific riverine export in western (4.5 g C m−2 year−1) and lowest (1.7 g C m−2 year−1) in subarctic Norway. In west and middle Norway, river OC export was approximately equal to carbon accumulation in soils and wetlands, while it was 50 % of soil and wetland carbon accumulation in southeast and subarctic Norway. Lateral aquatic transport of carbon is not explicitly accounted for in forest soil carbon accumulation estimates, although aquatic fluxes represent a climate-dependent carbon loss from soil carbon pools. The lack of methods that adequately account for lateral fluxes in carbon balances adds considerable uncertainty to soil carbon sink estimates. Climate warming and associated changes in precipitation may result in substantial alterations of terrestrial and aquatic carbon fluxes, with uncertain implications for the terrestrial carbon sink of northern landscapes.acceptedVersio

Tålegrenser for forsuring og overskridelser for Høyangervassdraget i Vestland fylke

Prosjektleder: Cathrine Brecke GundersenDet har blitt beregnet tålegrenser for forsuring og overskridelse av disse for Høyangervassdraget og separat for delnedbørfeltene Håland, Gautingsdal og Eiriksdal. Overskridelser er beregnet for dagens (årene 2017-2021) og framtidige (år 2030 og 2050) avsetninger av svovel og nitrogen. Både SSWC- og FAB-modellene ble benyttet. Resultatene viser ingen overskridelse i nedbørfeltene for alle tidsperiodene. På grunn av forsinkelser i systemene kan det være forsuring selv om tålegrensene ikke er overskredet. Men så lenge det ikke er overskridelse, vil forsuringen gradvis avta, og de sure episodene vil bli mindre hyppigere og alvorlige.Statsforvalteren i VestlandpublishedVersio

European Freshwater Ecosystem Assessment: Cross-walk between the Water Framework Directive and Habitats Directive types, status and pressures

The EU policies on the freshwater environment and nature and biodiversity are closely linked. The aims of the Water Framework Directive (WFD) and the Habitat Directive (HD) are to achieve good status for water bodies (WFD) and for habitats and species (HD) respectively. The types of rivers and lakes and their ecological status and pressures under the WFD are not directly comparable to the conservation status and threats for freshwater habitats and species under the HD (EC 2011a). The objective of this study has been to explore the possibilities of linking WFD and HD information on types of water bodies and habitats, and their status, pressures and measures, using WISE WFD information on types, ecological status, pressures and measures (EEA 2012, ETC-ICM 2012) and HD information on habitat types, conservation status and threats (EC 2007). The results may be used as input to the EEA Freshwater Ecosystem Assessment in 2015, and also for future European assessments of specific objectives, status and trends for various types of rivers and lakes after the reporting of the WFD 2nd RBMPs and the next HD article 17 reporting. The outcome may also be used as a basis for discussions of the potential and limitations for WFD and HD synergies in terms of monitoring programmes, assessment systems and measures to improve status. The general methodology used in this report is to analyse data and information reported by Member States on WFD types, ecological status and pressures in river and lake water bodies and on Habitats Directive freshwater habitats and their conservation status and threats. The major data sources used are the WISE-WFD database and the HD Article 17 databaseJRC.H.1-Water Resource

Using in situ sensor-based monitoring to study impacts of climate change on river water quality and element fluxes

Prosjektleder: Øyvind KasteThe report contains an analysis of high-frequency sensor data from two rivers included in the Norwegian River Monitoring Programme; Storelva in southern Norway and Målselva in northern Norway. The main aim of the report is to combine in situ sensor-based monitoring data with climate, hydrology and water chemistry data to study impacts of climate change on river water quality and element fluxes. The report also highlights challenges, opportunities and the strong potential for sensor-based monitoring to yield new knowledge related to climate change impacts on river water quality.Norwegian Environment AgencypublishedVersio

A new broad typology for rivers and lakes in Europe: Development and application for large-scale environmental assessments

European countries have defined >1000 national river types and >400 national lake types to implement the EU Water Framework Directive (WFD). In addition, common river and lake types have been defined within regions of Europe for intercalibrating the national classification systems for ecological status of water bodies. However, only a low proportion of national types correspond to these common intercalibration types. This causes uncertainty concerning whether the classification of ecological status is consistent across countries. Therefore, through an extensive dialogue with and data provision from all EU countries, we have developed a generic typology for European rivers and lakes. This new broad typology reflects the natural variability in the most commonly used environmental type descriptors: altitude, size and geology, as well as mean depth for lakes. These broad types capture 60–70% of all national WFD types including almost 80% of all European river and lake water bodies in almost all EU countries and can also be linked to all the common intercalibration types. The typology provides a new framework for large-scale assessments across country borders, as demonstrated with an assessment of ecological status and pressures based on European data from the 2nd set of river basin management plans. The typology can also be used for a variety of other large-scale assessments, such as reviewing and linking the water body types to habitat types under the Habitats Directive and the European Nature Information System (EUNIS), as well as comparing type-specific limit values for nutrients and other supporting quality elements across countries. Thus, the broad typology can build the basis for all scientific outputs of managerial relevance related to water body types

Trends and patterns in surface water chemistry in Europe and North America between 1990 and 2016, with particular focus on changes in land use as a confounding factor for recovery

The report presents trends in sulphate, nitrate, chloride, base cations, ANC (acid neutralising capacity), pH and DOC at circa 500 ICP Waters sites in Europe and North America for the period 1990-2016. Time series were analysed for trends in annual median values, annual extreme values and change points, that indicate years with sudden changes in trend or level. Also provided is a brief overview of possible implications of land use change for recovery of acidified surface waters

Responses of benthic invertebrates to chemical recovery from acidification

Prosjektleder: Heleen de WitThe report provides an assessment of biological recovery from acidification in freshwater environments in Europe. The report consists of two parts, a regional data analysis based on an international dataset of biological and water chemical records, and a collection of national contributions on monitoring and assessment of biological recovery in different countries. The regional analysis showed that 47% of all included rivers (21 sites, for the period 1994-2018) and 35% percent of all lakes (34 sites, for the period 2000 to 2018) showed significant increases in species richness. Correlations between species diversity and water chemical components (ANC, pH, SO4) were found, supporting that the biological responses were related to chemical recovery. Additionally, the composition of functional traits in rivers underwent significant changes over time. Both parts of the report demonstrate ongoing biological recovery from acidification in European acid-sensitive freshwater environments.Norwegian Ministry of Climate and Environment, United Nations Economic Commission for Europe (UNECE)publishedVersio

Modelling study of soil C, N and pH response to air pollution and climate change using European LTER site observations

Current climate warming is expected to continue in coming decades, whereas high N deposition may stabilize, in contrast to the clear decrease in S deposition. These pressures have distinctive regional patterns and their resulting impact on soil conditions is modified by local site characteristics. We have applied the VSD+ soil dynamic model to study impacts of deposition and climate change on soil properties, using MetHyd and GrowUp as pre-processors to provide input to VSD+. The single-layer soil model VSD+ accounts for processes of organic C and N turnover, as well as charge and mass balances of elements, cation exchange and base cation weathering. We calibrated VSD+ at 26 ecosystem study sites throughout Europe using observed conditions, and simulated key soil properties: soil solution pH (pH), soil base saturation (BS) and soil organic carbon and nitrogen ratio (C:N) under projected deposition of N and S, and climate warming until 2100. The sites are forested, located in the Mediterranean, forested alpine, Atlantic, continental and boreal regions. They represent the long-term ecological research (LTER) Europe network, including sites of the ICP Forests and ICP Integrated Monitoring (IM) programmes under the UNECE Convention on Long-range Transboundary Air Pollution (LRTAP), providing high quality long-term data on ecosystem response. Simulated future soil conditions improved under projected decrease in deposition and current climate conditions: higher pH, BS and C:N at 21, 16 and 12 of the sites, respectively. When climate change was included in the scenario analysis, the variability of the results increased. Climate warming resulted in higher simulated pH in most cases, and higher BS and C:N in roughly half of the cases. Especially the increase in C:N was more marked with climate warming. The study illustrates the value of LTER sites for applying models to predict soil responses to multiple environmental changes