IWRA Executive Office

OS4d Remote sensing, DSS and GIS applications

abstract 150

Remote Sensing and Hydrochemistry of Lakes-Groundwater Interaction

Author(s): Sarah Tweed, Marc Leblanc, Ian Cartwright
Sarah Tweed: School of Earth and Environmental Sciences, James Cook University, Cairns, QLD, 4870, Australia Ph: +61 7 4042 1468 Fax: +61 7 4042 1364 Email: sarah.tweed@jcu.edu.au

Keyword(s): remote sensing, hydrochemistry, groundwater discharge, lakes

Article:

Poster:

Session: OS4d Remote sensing, DSS and GIS applications

AbstractTo manage or mitigate many of the

hydrological issues threatening lakes, including increasing salinisation, frequent algae blooms, and the sensitivity of

lakes to changes in land use and climate, information on the interaction between the surface water and groundwater

systems is required. In southeastern Australia, many of the lakes are sustained by groundwater discharge or through

flow. However, the interaction between groundwater and surface water in these areas is often poorly defined due to

the limited hydro(geo)logical monitoring data, and the lakes are generally small and widely dispersed across large

catchments.

This study highlights remote sensing techniques using optical and lidar data that can be used to

investigate lakes and groundwater interactions across regions where there is either limited historical hydrogeological

data, or where the bore network is insufficient. Satellite remote sensing offers the ability to cover the surface of large

areas with relatively fine spatial resolution. This is important to be able to (i) monitor numerous water bodies over

large regions, and (ii) incorporate catchment-scale hydrological processes. Whereas hydrochemistry offers an

accumulative record of dominant hydrological processes affecting lakes water with time. Where time series of

physical hydro(geo)logical monitoring data is absent, both remote sensing and hydrochemistry can be used to

ascertain dominant relationships between the surface water and groundwater systems.

The study area is the

Corangamite Catchment, located in the sub-humid region of southeast Australia. Much of the study region is a

significant agricultural area and also contains wetlands with high cultural and ecological value (RAMSAR). The

catchment covers an area of 1,334,000 ha, and contains over 1,500 wetlands and lakes many of which are

ungauged and on private property. The optical and lidar remote sensing data were used in combination with the

seasonal hydrochemistry to distinguish between lakes subject to groundwater discharge, through flow or

recharge.

Events

The congress

Programme

Practical Infos

Remote Sensing and Hydrochemistry of Lakes-Groundwater Interaction