The individual response of saline lakes to a severe drought
Tweed, Sarah, Grace, Michael, LeBlanc, Marc, Cartwright, Ian, and Smithyman, Donna (2011) The individual response of saline lakes to a severe drought. Science of the Total Environment, 409 (19). pp. 3919-3933.
|PDF (Published Version) - Repository staff only - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader|
View at Publisher Website: http://dx.doi.org/10.1016/j.scitotenv.20...
A severe protracted drought between 1997 and 2009 has altered the physical and chemical hydrology of a series of lakes in the Corangamite Basin of southeast Australia. Leading up to the drying out of most lakes (many for the first time on record), we document the changes in lakes' water quantity (water levels and inundation), salinity (Cl concentrations), salinity processes (Cl/Br ratios), nutrient concentrations and ratios (ammonia, phosphate and NOx (nitrate and nitrite)) and algae (as chlorophyll-a) for six lakes. All lakes show record declines in inundated areas and increases in salinity from pre-drought (< 1997) to drought conditions. However, the magnitude of change in salinity varies for different lakes, and there is no systematic change in the controls on lake salinity processes. Four lakes show no change in salinity processes, one lake shows the beginnings of change; where halite dissolution reactions increased closer to the time of the lake drying up, and another lake shows a marked shift from predominantly evaporation to the cyclic dissolution and precipitation of halite. Changes in filterable reactive phosphorus (FRP) values and lake N and P limitation predictions also showed little systematic correlation with changes in lake salinity, and nutrient values varied between lakes and over time. The decline in NOx concentrations in lakes where electrical conductivity (EC) values were above 100 mS/cm indicates some correlation with changes in salinity. Largely, these lakes exhibit individual changes in water quality parameters and salinity processes in response to the drought, indicating that while the stress of drought is regional, the hydrochemical response is local. In future changing climates, these results suggest that the catchment adaption strategies will require comprehensive plans for individual lake systems.
|Item Type:||Article (Refereed Research - C1)|
|Keywords:||drought; lakes; water quality; climate change; salinity; remote sensing|
|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 > 960905 Farmland, Arable Cropland and Permanent Cropland Water Management @ 100%|
|Deposited On:||13 Mar 2012 12:19|
|Last Modified:||18 Oct 2013 01:27|
Last 12 Months: 0
|Citation Counts with External Providers:|
Repository Staff Only: item control page