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| Titel |
Land use influences on acidification and recovery of freshwaters in Galloway, south-west Scotland |
| VerfasserIn |
R. C. Helliwell, R. C. Ferrier, L. Johnston, J. Goodwin, R. Doughty |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1027-5606
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| Digitales Dokument |
URL |
| Erschienen |
In: Hydrology and Earth System Sciences ; 5, no. 3 ; Nr. 5, no. 3, S.451-458 |
| Datensatznummer |
250002566
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| Publikation (Nr.) |
 copernicus.org/hess-5-451-2001.pdf |
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| Zusammenfassung |
| The long term response of
surface waters to changes in sulphur deposition and afforestation is
investigated for three upland river systems in the
Galloway region of south-west Scotland. From 1984-1999, these rivers exhibited a
statistically significant decline in non-marine sulphate concentrations
in response to reduced acid deposition. This reduction in non-marine sulphate
was, however, insufficient to induce a pH recovery over
the period. A statistically significant increase in river pH was observed
between 1956-1970 (0.05 yr-1) when subsidised agricultural lime
payments were at a maximum. In 1976, this subsidy ceased and surface waters have
progressively acidified. In addition, climatic change is
found to influence long-term trends in pH. Mean annual pH was greatest during a
dry period between 1969-1973 when total annual discharge
was low. Thereafter, pH declined gradually in response to higher rainfall and
increased total annual discharge. Overall, surface waters
draining the afforested catchments of the Rivers Cree and Bladnoch are more acid
than those draining the moorland catchment of the Luce.
These results indicate that in afforested catchments, current reductions in
sulphur emissions have not led to an observed improvement in
the acid status of surface waters. Forestry, therefore, represents a confounding
factor with regard to chemical recovery from acidification in
this region.
Keywords: acidification, afforestation, deposition, rivers, lochs,
non-marine sulphate, pH |
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