Prymnesium parvum: The Norwegian Experience1

Johnsen, Torbjørn M., Wenche Eikrem, Christine D. Olseng, Knut E. Tollefsen, and Vilhelm Bjerknes, 2010. Prymnesium parvum: The Norwegian Experience. Journal of the American Water Resources Association (JAWRA) 46(1):6-13. DOI: 10.1111/j.1752-1688.2009.00386.x Abstract: In Norwegian waters, Prymnesium parvum has been reported from Oslofjorden in the south to Spitzbergen in the north. However, blooms of P. parvum have only been reported from the Sandsfjorden system in Ryfylke, Western Norway where the salinity of the permanent brackish layer (2-5 m) typically is in the range of 4-7 psu during the summer months. The first bloom on record occurred in 1989, and it killed 750 metric tons of caged salmon and trout which was a significant economic loss to the fish farming industry. Toxic blooms occurred as well in subsequent years and the number of fish farms in the area decreased considerably as did the occurrence of P. parvum. In 2005, fish farming was reintroduced to the area and again, in 2007 a toxic bloom of P. parvum killed 135 metric tons of caged fish. The Norwegian Institute for Water Research has, in collaboration with “Erfjord Stamfisk” fish farm, set up a monitoring program that includes light microscopy cell counts of Prymnesium, water quality measurements, and observation of the caged fish. A submergible fish net was mounted over the fish pens and during the toxic outbreak of P. parvum in July-August 2007, which was as previous years confined to the upper brackish water layer, the fish nets were lowered to 10 m depths below the surface and fish feeding was temporarily stopped. Despite substantial weight loss, the fish survived the toxic bloom and the economic loss was minimal. Monitoring of P. parvum bloom dynamics in 2007 revealed that populations were initially dominated by the nonmotile forms which were gradually replaced by the flagellated forms. Toxicity was observed when the flagellated cells dominated populations in the summer. Chrysochromulina, solitary small Chaetoceros species, and small centric diatoms co-existed with P. parvum during the monitoring period (June-October).     

Trends of nitrogen in air and precipitation: model results and observations at EMEP sites in Europe, 1980--2003

We analyze trends of some nitrogen compounds using long-term measurements and results from the EMEP (co-operative programme for monitoring and evaluation of the long-range transmissions of air pollutants in Europe) chemical transport model at EMEP sites. We find statistically significant declines at the majority of sites for NH(x) (sum of ammonia and ammonium) in air and for nitrate and ammonium in precipitation, but only at a few sites for xNO3 (sum of nitrate and nitric acid) in air. Model calculations and measurements give similar results. We demonstrate that the lack of trends for xNO3 in air at least partly can be attributed to a shift in the equilibrium between nitric acid and ammonium nitrate towards particulate phase, caused by reductions in the sulfur dioxide emissions.     

Landscape protection as a tool for managing agricultural landscapes in Norway

Norwegian Protected Landscapes aim to preserve landscape character. As most of the agricultural land in Protected Landscapes is privately owned, the attitudes and behaviour of farmers are crucial in achieving this goal. We present results of a nationwide questionnaire to farmers who owned or managed farmland in Protected Landscapes. Thirty-eight percent of the respondents claimed that their farm business had been changed as a consequence of landscape protection. Niche products and alternative income possibilities, commonly forwarded as potential benefits of landscape protection status, had generally not been realised. Although we found that most farmers agreed on the importance of taking care of cultural landscapes, 76% felt that this was best done by using rather than protecting the landscape. The study revealed negative attitudes towards municipal authorities. A quarter of respondents were strongly against the establishment of new Protected Landscapes, even if they were compensated for economic losses. Based on results of the study we suggest that major improvements to the protection system could be made by improving communication between management authorities and farmers, and ensuring real involvement of farmers in making and carrying out management plans.     

Local opposition against high-voltage grids: public responses to agency-caused science–policy trolls

High-voltage (hV) transmission grids are projects of societal importance that potentially have controversial social and environmental impacts. Former research shows that public opposition is sparked by the perception of negative local impacts and unjust concessionary processes. In this paper, we complement these perspectives by assessing the institutional practices of the regulatory agencies in dealing with scientific uncertainties. The regulatory agencies’ ‘ways of doing things’ are often designed to serve policy and management needs. A critical point is that the demarcation between scientifically based facts, values and assessments is often blurred in the decision-making process. This paper draws on two Norwegian case studies to investigate how the regulatory agencies dealt with (1) electromagnetic fields and health risks and (2) overhead lines versus sea cables. We argue that ambiguities and uncertainties that arise in the hV transmission line processes create ‘trolls’, and we explore how the local inhabitants and affected stakeholders in the two cases responded to these and how it triggered further opposition. By investigating how and why trolls appear and are handled, we conclude by discussing how public opposition related to hV transmission grids may be reduced – and how some ‘trolls’ may crack.     

DNA damage induced by ultraviolet radiation in coral-reef microbial communities

Ultraviolet radiation (UVR) has been implicated in coral-bleaching processes and UVR may create stress to marine organisms by damage to DNA. Absorption of energy from UVB (280 to 320 nm) induces direct damage to DNA via cyclobutane pyrimidine dimer photoproduct-formation. We examined the extent of DNA damage created by UVR in coral reef microbial communities and whether the coral-surface microlayer (CSM) provides protection from UVR to the microorganisms found there. Diel patterns and depth profiles of UVR effects were examined in coral mucus (coral-surface microlayer, CSM) from Montastraea faveolata and Colpophyllia natans, and water-column samples of similar depths. UV-induced photodamage was determined using a radioimmunoassay specific for cyclobutane pyrimidine dimers (thymine dimers). Significant photodamage was detected in water-column and CSM samples, although the level of damage in CSM samples was consistently lower than in water-column samples collected from the same depth, suggesting the presence of photoprotective mechanisms within the CSM. Diel patterns of photodamage were detected in both water-column and CSM samples, but peak damage occurred earlier in the day for the CSM samples, suggesting differences in damage and repair kinetics between the water column and CSM. The results suggest that microorganisms within the CSM are afforded some protection from UVR stress and that changes in the amount of DNA damage in these organisms may be an indicator of changing UVR stress to corals. Received: 10 January 1997 / Accepted: 15 September 1997     

Field Intercomparison of Main Components in Air in EMEP

Within the European monitoring network (EMEP, ) several different sampling procedures for measuring the main air components have been applied. This has contributed to systematic concentration differences and a comparability problem. Since 1997 co-located experiments in 15 countries have been carried out to quantify these differences. In addition, three major measurement campaigns were organized by EMEP between 1985 and 1991. Differences among results depend on the concentration level and methods used. The decrease in SO₂ concentrations over the last twenty years has placed greater demands on the methodology. Absorbing solutions methods for SO₂, (H₂O₂ and tetrachloromercurate (TCM)) typically have higher detection limits than the reference method, which uses KOH impregnated filters. The TCM method also has problems with negative interference, especially in summertime. UV fluorescence monitors have in a few cases proven to give good results, but interferences, detection limit and poor maintenance can be problems. For NO₂, many countries are using the TGS absorption solution method, which has a higher detection limit than the reference method using NaI impregnated glass sinters. The Salzmann method gives unreliable results at concentrations below 1 μgN/m³, and even at higher concentrations the uncertainty is rather unsatisfactory. The chemiluminescence monitor with molybdenum converters tends to systematically overestimate NO₂ concentrations, possibly because zero-drift problems and the non-specific response to NO₂. Particulate sulphate measurements in general have lower bias and uncertainties than gas and other aerosol measurements.     

Public perception of river fish biodiversity in four European countries

Public support for biodiversity conservation is shaped by people's values and their knowledge, beliefs, and attitudes toward the environment. We conducted the first multinational representative survey of the general public's perceptions of river fish biodiversity in France, Germany, Norway, and Sweden. For the online survey, 1000 respondents per country were randomly selected from large panels following country-specific quotas set on age, gender, and educational level. Questions covered people's level of knowledge, beliefs, values, and attitudes toward river fish, environmental threats, and conservation measures. We found that the public had limited knowledge of freshwater fishes. Two non-native species, rainbow trout (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis), were widely perceived as native, whereas native Atlantic salmon (Salmo salar) was mostly classified as native in Scandinavia and largely as non-native in central Europe. These results suggest an extinction of experience paralleling the extirpation or decline of salmon stocks in countries such as Germany and France. Respondents thought pollution was the dominant threat to riverine fish biodiversity. In reality, habitat loss, dams, and the spread of non-native fishes are equally important. Despite limited biological knowledge, respondents from all countries held an overwhelmingly proecological worldview, supported conservation stocking, and appreciated native fishes, although only a minority interacted with them directly. Differences among the 4 countries related to several conservation issues. For example, threats to biodiversity stemming from aquaculture were perceived as more prevalent in Norway compared with the other 3 countries. Promoting fish conservation based on charismatic species and use values of fishes may work well in countries with a strong economic and cultural link to the freshwater environment, such as Norway. In countries where people rather abstractly care for nature, focusing conservation messaging on broader ecosystem traits and non-use values of fishes is likely to win more support.     

Effects of landscape protection on farm management and farmers' income in Norway

Protected Landscapes (PLs) are increasingly used in Norway to conserve cultural (human modified) landscapes. In many cases the maintenance of agricultural activities in PLs is required to preserve landscape character. Whilst research exists on land conservation policies in general, the particular effects of PL on management and adjustment of the farms involved have not received attention in the literature. We present results from a questionnaire sent to owners of agricultural land within PLs in Norway. Whilst landowners were divided upon the effects of PLs on farm management, the economic situation of the farm was little affected. Furthermore, changes in farm management after the establishment of a PL did not seem to have been driven by the establishment of the PLs per se. Most importantly, farm management changes were related to potential options to develop the farm and its land. A statistical model showed that PL-farms did not differ significantly from farms outside PL in the development of their land use or animal husbandry. Our findings thus indicate that the establishment of PL played a minor role as a driving force of changes in farm management and farm income.     

An evaluation of two fluorescence screening methods for the determination of chrysene metabolites in fish bile

Two screening methods, synchronous fluorescence spectrometry (SFS) and high performance liquid chromatography with fluorescence detection (HPLC-F), have been evaluated for their suitability in determining chrysene metabolites in fish bile. The optimal wavelength pair, excitation/emission 272/374 nm, for SFS measurements of chrysene metabolites was identified by analysis of bile taken from fish exposed to the pure compound. This analysis revealed in addition some information about the metabolite pattern. However, when bile from fish exposed to complex and environmentally relevant mixtures of polycyclic aromatic hydrocarbons (PAHs) was analysed using these methods, identification of the chrysene metabolites was poor. Analysis of bile taken from fish exposed to single PAHs identified other three- and four-ring aromatics as the main interfering compounds. Both methods were equally able to discriminate between impacted and reference sites by determination of relative concentrations of fluorescent three- and four-ring aromatics.     

Consumptive orientation of anglers in Engerdal,Norway

In a study of consumptiveness among Swedish and Norwegian anglers in Engerdal, eastern Norway, three segments of low-, mid-, and high-consumptive anglers were identified by replicating a methodology of an earlier study of North American anglers. The Engerdal anglers were somewhat more catch-oriented than the North American anglers. Anglers in Norway fish to satisfy a complex set of experience preferences. Low-consumptive anglers rate nature experiences higher than mid- and high-consumptive anglers. High-consumptive anglers have a somewhat narrower range of experience preferences and are more oriented towards competitive aspects of fishing. All anglers generally support management efforts directed toward restricting other types of use of the waters, such as reducing pollution and reducing local fishermen's leisure gill-net fishing. They also support stocking of fish, but oppose actions restricting angling. However, low-consumptive anglers do not oppose angling restrictions to the same degree as mid- and high-consumptive groups. Low-consumptive fishermen show a higher degree of specialization and report higher overall satisfaction with their fishing trips than the other two groups.