| Records |
| Author |
Heaton, T.H.E. |
| Title |
Sources of the nitrate in phreatic groundwater in the western Kalahari |
Type |
Journal Article |
| Year |
1984 |
Publication |
Journal of Hydrology |
Abbreviated Journal |
|
| Volume |
67 |
Issue |
1 |
Pages  |
249-259 |
| Keywords |
|
| Abstract |
Elevated levels of nitrate occur in phreatic groundwater in the western Kalahari, Namibia. Nitrate in water containing 0.4–3.1 meq NO−3l−1, of widespread occurrence, has δ15N values in the range +4.9 to +8.0‰, suggesting natural derivation from the soil. The sporadic occurrence of very high levels of nitrate (> 4 meq NO−3l−1), which has δ15N between +9.3 to +18.7‰, reflects pollution derived from animal waste. The importance of considering the possible isotopic effects of denitrification, and the significance of leaching in the nitrogen budget of the Kalahari soil, are also discussed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-1694 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
THL @ christoph.kuells @ Heaton1984249 |
Serial |
278 |
| Permanent link to this record |
| |
|
| |
| Author |
Lightfoot, D.R. |
| Title |
Moroccan khettara: Traditional irrigation and progressive desiccation |
Type |
Journal Article |
| Year |
1996 |
Publication |
Geoforum |
Abbreviated Journal |
|
| Volume |
27 |
Issue |
2 |
Pages |
261-273 |
| Keywords |
|
| Abstract |
A 300 km network of khettara (qanat) subsurface irrigation channels was excavated in the Tafilalt basin beginning in the late 14th century. More than 75 of these chains provided perennial water following the breakup of the ancient city of Sijilmassa. Khettara continued to function for much of the northern oasis until the early 1970s, when new technologies and government policies forced changes. Data on origins, maintenance, and current use were collected from archival sources, aerial photographs, Landsat imagery, and from interviews. Insufficient water resources and unsustainable practices have dramatically lowered the water table, drying up khettara. This has resulted in a loss of local control over water resources, abandonment of a sustainable irrigation system, and progressive desiccation. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0016-7185 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
THL @ christoph.kuells @ Lightfoot1996261 |
Serial |
257 |
| Permanent link to this record |
| |
|
| |
| Author |
Morin, E.; Grodek, T.; Dahan, O.; Benito, G.; Külls, C.; Jacoby, Y.; Van Langenhove, G.; Seely, M.; Enzel, Y. |
| Title |
Flood routing and alluvial aquifer recharge along the ephemeral arid Kuiseb River, Namibia |
Type |
Journal Article |
| Year |
2009 |
Publication |
Journal of Hydrology |
Abbreviated Journal |
|
| Volume |
368 |
Issue |
1-4 |
Pages |
262-275 |
| Keywords |
|
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
THL @ christoph.kuells @ Morin2009flood |
Serial |
26 |
| Permanent link to this record |
| |
|
| |
| Author |
Külls, C.H.; Eichinger, F.; Fader, H.J.; Leistert, H.; Lorenz, G.; Szakacs, E. |
| Title |
New Environmental Analytical Techniques to Monitor Carbon Sequestration |
Type |
Conference Article |
| Year |
2011 |
Publication |
1st EAGE Sustainable Earth Sciences (SES) Conference and Exhibition |
Abbreviated Journal |
|
| Volume |
|
Issue |
|
Pages |
268 |
| Keywords |
|
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
European Association of Geoscientists & Engineers |
| Notes |
|
Approved |
no |
| Call Number |
THL @ christoph.kuells @ Kuells2011new |
Serial |
47 |
| Permanent link to this record |
| |
|
| |
| Author |
Vogel, J.C.; Talma, A.S.; Heaton, T.H.E.; Kronfeld, J. |
| Title |
Evaluating the rate of migration of an uranium deposition front within the Uitenhage Aquifer |
Type |
Journal Article |
| Year |
1999 |
Publication |
Journal of Geochemical Exploration |
Abbreviated Journal |
|
| Volume |
66 |
Issue |
1 |
Pages |
269-276 |
| Keywords |
redox changes in aquifer, sandstone-type uranium deposit, South Africa, uranium series |
| Abstract |
The solubility of uranium in groundwater is very sensitive to changes in redox conditions. Many secondary (sandstone-type) uranium deposits have been formed when soluble U has precipitated after encountering reducing conditions in the subsurface. In the groundwater of the Uitenhage Aquifer (Cape Province, South Africa), 238U-series isotopes were used to assist in studying the history of the reducing barrier. Uranium isotopes were used to determine the present position of the barrier. Radium and radon were used to evaluate the path of migration that the front of the oxygen depletion zone has taken over the past 105 years. During this time the reducing barrier has moved, leaving in its wake a trail of U in various stages of secular equilibrium with its daughter 230Th. The 226Ra daughter of 230Th is not very mobile. Its growth upon the aquifer wall is reflected in the Rn content of the water. This in turn, due to the relatively great age of the water, indicates the extent of the 230Th ingrowth (from precipitated U) that took place before the barrier migrated. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0375-6742 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
THL @ christoph.kuells @ vogel_evaluating_1999 |
Serial |
126 |
| Permanent link to this record |
