TY  - JOUR
AU  - Heaton, T. H. E.
AU  - Talma, A. S.
AU  - Vogel, J. C.
PY  - 1983//
TI  - Origin and history of nitrate in confined groundwater in the western Kalahari
JO  - Journal of Hydrology
SP  - 243
EP  - 262
VL  - 62
IS  - 1
N2  - Data are presented for nitrate, dinitrogen and argon concentrations and 15N14N ratios in groundwater, with radiocarbon ages up to 40,000 yr. for three confined sandstone aquifers in the western Kalahari of South West Africa/Namibia. The nitrate is probably generated within the soil of the recharge areas, and its production rate during the period 3000-40,000 B.P. has remained between 0.5 and 1.6 meq NO−3l−1 of recharge water, with ° 15N between + 4 and + 8‰. Variations in the amount of nitrate and of “excess air” in groundwater recharge are found, and can only reflect changes in the environmental conditions during recharge. They must therefore be caused by the climatic changes that have taken place during the past 25,000 yr.
SN  - 0022-1694
UR  - https://www.sciencedirect.com/science/article/pii/0022169483901051
N1  - exported from refbase (http://www.uhydro.de/base/show.php?record=282), last updated on Fri, 02 Feb 2024 13:01:10 +0100
ID  - Heaton_etal1983
ER  -