Remote sensing and hydrochemistry of lakes-groundwater interaction
Tweed, Sarah, Leblanc, Marc, and Cartwright, Ian (2008) Remote sensing and hydrochemistry of lakes-groundwater interaction. In: Proceedings of the 13th IWRA World Water Congress 2008, pp. 1-14. From: 13th IWRA World Water Congress 2008, 01-04 September 2008, Montpellier, France.
Southeast Australia is currently experiencing a severe multi-year drought caused by a significant rainfall deficit and record high temperatures. The vast system of lakes that occupy the Corangamite Catchment is affected by this drought with a significant drop in the water levels and a decline in water quality. Physical and chemical hydrological data are used in combination with remote sensing techniques to study (i) how drought conditions affect groundwater and lakes interaction, and (ii) how this, in turn, impacts on lakes quality. The data record spans over 14 years, and includes a pre-drought (1992- 1996) and drought (1997-2006) period. The drought has altered interaction of lakes with the groundwater system. By 2006, 10 of the 28 monitored lakes have changed from groundwater throughflow or discharge lakes to recharge lakes that are now dry. Cl/Br ratios indicate that the remaining lakes are throughflow lakes. The drought has also resulted in increased lake salinity levels. By 2006, 7 lakes have evaporites, where previously none were observed. The increase in lake salinity is due to increased evaporation, or a combination of increases in the evaporation and groundwater to lakes volume ratios. Therefore, although these are throughflow lakes, evaporation is a controlling factor on lakes quality, and although lakes may be sustained by hydraulic gradients with groundwater, there is no guarantee that the water quality will be maintained for ecosystem health.
|Item Type:||Conference Item (Refereed Research Paper - E1)|
|Date Deposited:||04 Sep 2009 07:08|
|FoR Codes:||04 EARTH SCIENCES > 0406 Physical Geography and Environmental Geoscience > 040603 Hydrogeology @ 50%
04 EARTH SCIENCES > 0406 Physical Geography and Environmental Geoscience > 040608 Surfacewater Hydrology @ 50%
|SEO Codes:||96 ENVIRONMENT > 9609 Land and Water Management > 960999 Land and Water Management of Environments not elsewhere classified @ 100%|
Last 12 Months: 4