Browsing NIVA Open Access Archive by Author "Wright, R."

Acidification and Atlantic salmon critical limits for Norwegian rivers

Kroglund, F.; Wright, R.; Burchart, C. (NIVA-rapport;4501, Research report, 2002)

An analysis of water chemistry and salmon population status based on data for 1993-94 shows that of 73 salmon rivers in Norway, 23 have extinct populations and an additional 22 have affected populations. Acidification is ...

Assessment of Trends and Leaching of Nitrogen at ICP Waters Sites (Europe and North America) (ICP Waters report 54/2001)

Skjelkvåle, B.L.; Olendrzynski, Krzysztof; Stoddard, John; Tarrason, Leonor; Traaen, T.S.; Tørseth, Kjetil; Windjusveen, Sofia; Wright, R. (NIVA-rapport;4383, Research report, 2001-01)

The ICP Waters database currently holds data for 204 sites in Europe and North America. These data were evaluated with respect to nitrate concentrations. About 50% of the sites currently have nitrate concentrations indicative ...

Atmospheric deposition of nitrogen, runoff of organic nitrogen, and critical loads for soils and waters

Wright, R.; Raastad, I.A.; Kaste, Ø. (NIVA-rapport;3592, Research report, 1997)

Here we test the hypothesis that increased deposition of inorganic N compounds leads to increased leachingand runoff of organic N and thus a higher critical load. We use mainly Norwegian data from input-output fluxes at ...

Beregning av dagens og framtidig kalkbehov for innsjøer og lakseelver i Norge

Hindar, A.; Kroglund, F.; Wright, R.; Skjelkvåle, B.L.; Henriksen, A. (NIVA-rapport;5619, Research report, 2008)

Forsuringssituasjonen i Norge har vært i raskt bedring over en periode på 20 år. Det har medført merkbare endringer i vannkjemien i innsjøer og elver. pH og syrenøytraliserende kapasitet (ANC) har økt og konsentrasjonen ...

Beregning av opprinnelig vannkjemi i forsurede innsjøer - uttesting av en regnemodell

Hindar, A.; Wright, R. (NIVA-rapport;4546, Research report, 2002)

Vi har laget et excel-basert regneark som kan brukes for å beregne den vannkjemi innsjøer hadde før forsuring, dvs. for omlag 100 år siden. pH og de viktigste hovedioner regnes ut basert på kjente empiriske sammenhenger ...

Bruk av dynamiske modeller for vurdering av vann- og jordforsuring som følge av redusert tilførsel av sur nedbør

Wright, R. (NIVA-rapport;3148, Research report, 1995)

Som følge av den nye svovel-protokollen vil tilførselen av sur nedbør til Norge avta i årene fremover. Den nye tilførselmønsteret vil endre omfang og utbredelse av forsuringsskader i Norge. Dynamiske modeller som beskriver ...

Changes in the chemistry of Lake Hovvatn, Norway, following liming and reacidification

Wright, R. (NIVA-rapport;1657, Research report, 1984)

Hovvatn, a 1 km², chronically-acidified lake in southernmost Norway, was treated with 200 metric tons of powdered limestone in March 1981. An additional 40 metric tons were spread uniformly on the ice of a 0.045 km² pond ...

CLIMEX Project: Climate data for first year of treatment April 1994 - March 1995

Wright, R.; Indrøy, A.-S.; Høgberget, R.; Lukerwille, A.S.; Willbergh, M. (NIVA-rapport;3339, Research report, 1995)

Climate change treatment began in April 1994 at the 2 experimental catchments. At KIM CO2 is increased (to 560 ppm) and air is heated (by 3¨ C in summer and 5¨ C in winter). At EGIL soil is heated. Except for an initial ...

Climex project: Data report for June 1994 - May 1999

Buan, A.K.; Høgberget, R.; Wright, R. (NIVA-rapport;4157, Research report, 1999)

CLIMEX project was conducted from May 1994 to June 1998 and involved whole ecosystem manipulation of temperature and CO2 at the catchment scale. Measurements of precipitation and runoff continued for one-year post-treatment ...

CLIMEX project: Response of runoff chemistry after 2 years of elevated CO2 and temperature

Wright, R.; Lükewille, A. (NIVA-rapport;3542, Research report, 1996)

CLIMEX is an integrated, whole-ecosystem research project studying the response of entire forested catchments to increased CO2 and temperature. KIM catchment receives clean rain, elevated CO2 and elevated air temperature. ...

Critical loads for soil in Norway, Nordmoen

Wright, R.; Stuanes, A.; Frogner, T. (NIVA-rapport;2605, Research report, 1991)

We evaluate the critical load for soil and water at Nordmoen using the dynamic model Magic, the static PROFILE model, and the empirical method as suggested by the mapping handbook. Nordmoen is located about 60 km N of Oslo ...

Critical loads for soils in Norway. Preliminary assessment based on data from 9 calibrated catchments

Wright, R.; Stuanes, A.; Reuss, J.O.; Flaten, M.B. (NIVA-rapport;2483, Research report, 1990)

Critical load for acid deposition with respect to soils are calculated for 9 calibrated catchments in southern Norway. Two methods recommended by the UN-ECE Handbook on Mapping Critical Loads were used: The stratic empirical ...

Critical Loads, Target Load Functions and Dynamic Modelling for Surface Waters and ICP Waters Sites (ICP Waters report 83/2006)

Wright, R.; Cosby, B.J.; Høgåsen, T.; Larssen, T.; Posch, M. (NIVA-rapport;5166, Research report, 2006-08)

Critical load functions (CLF) for ICP Water sites estimated with the FAB model and based on recent data (2000-02) do not differ greatly from those based on earlier data (1992-94/5). The ICP Waters sites in Europe are largely ...