 |
| Titel |
Surface water process and groundwater flow within a hydrologically complex floodplain wetland, Norfolk Broads, U.K. |
| VerfasserIn |
D. J. Gilvear, P. J. K. Sadler, J. H. Tellam, J. W. Lloyd |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1027-5606
|
| Digitales Dokument |
URL |
| Erschienen |
In: Hydrology and Earth System Sciences ; 1, no. 1 ; Nr. 1, no. 1, S.115-135 |
| Datensatznummer |
250000088
|
| Publikation (Nr.) |
 copernicus.org/hess-1-115-1997.pdf |
|
|
|
|
|
| Zusammenfassung |
| The patterns of variation in water quality for an acidic
stream draining plantation forest overlying acidic and acid sensitive gley
soils with shale and slate bedrock changed following the introduction of
a 45 m deep borchole near to the stream. During drilling, air flushing
of debris from the borehole cleared fracture routes for groundwater penetration
to the stream via the stream bed. Consequently, there were and there remain
marked increases in pH, alkalinity and calcium concentrations in the stream
water. The extent of this water quality improvement varies according to
flow. Under extreme highfiow conditions, most of the stream water is supplied
from near surface soil water sources and acidic stream waters (pH about
4.2) result. Under baseflow conditions, the stream water pH is about 7.0
upstream and about 7.5 downstream of the borehole. Under intermediate flow
conditions, the improvement in pH is most marked and values increase from
around 5 to around 6.3. For acid sensitive "hard rock" areas such as those
studied here, the bedrock has frequently been assumed to be both impermeable
and low in base cations. This study illustrates that this view may be incorrect,
and that groundwater may provide an important modifier of streamwater quality,
at least for slate and shale dominated hard rock areas. Indeed, the work
demonstrates clearly the potential for water quality remediation through
groundwater manipulation. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|