Nitrate leaching as a confounding factor in chemical recovery from acidification in UK upland waters

Over the period 1988–2002, data from 18 of the 22 lakes and streams in the UK Acid Waters Monitoring Network (AWMN) show clear trends of declining excess sulphate concentrations in response to reductions in sulphur deposition, but fewer trends in increasing pH or alkalinity. There has been no signif...

Full description

Saved in:
Bibliographic Details
Published inEnvironmental pollution (1987) Vol. 137; no. 1; pp. 73 - 82
Main Authors Curtis, C.J., Evans, C.D., Helliwell, R.C., Monteith, D.T.
Format Journal Article
LanguageEnglish
Published England Elsevier Ltd 01.09.2005
Subjects
Acid deposition
Acid Rain
acidification
Critical load
Environmental Monitoring - methods
Environmental Monitoring - statistics & numerical data
Geography
Humans
Hydrogen-Ion Concentration
lakes
leaching
N saturation
nitrate nitrogen
Nitrates - analysis
Nitrogen
Soil Pollutants
streams
sulfates
Sulphate
Time Factors
time series analysis
trend analysis
United Kingdom
Water Movements
water pollution
Water Pollution, Chemical - analysis
United Kingdom
British Isles
Sulphate
Critical load
Acid deposition
Nitrogen
N saturation
Online AccessGet full text

Cover

More Information
Summary:Over the period 1988–2002, data from 18 of the 22 lakes and streams in the UK Acid Waters Monitoring Network (AWMN) show clear trends of declining excess sulphate concentrations in response to reductions in sulphur deposition, but fewer trends in increasing pH or alkalinity. There has been no significant decline in the deposition of total nitrogen over the same period, and no sites show a trend in nitrate concentration. Peak nitrate concentrations have already surpassed excess sulphate on occasion in half of the AWMN sites. Furthermore, current understanding of terrestrial N saturation processes suggests that nitrate leaching from soils may increase, even under a constant N deposition load. Best-case projections indicate that nitrate will overtake sulphate as the major excess acid anion in many sites within 10 years, while worst-case predictions with steady-state models suggest that in the longer-term, nitrate could become the dominant excess acid anion in most of the UK. With declining excess sulphate, nitrate will become the dominant agent of continued anthropogenic acidification in many UK upland waters within a decade.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:0269-7491
1873-6424
DOI:10.1016/j.envpol.2004.12.032