Lets recap definition of a resource and a region importance of
water as a resource in Australia geographic characteristics of the
Murray-Darling Basin region Slide 2 Regional Resources A resource
is anything which occurs naturally or is created by humans provided
that people use it to satisfy a need or want. Regions are areas of
various scales that have characteristics and features that
distinguish them from other areas according to the elements used to
define them. Slide 3 Governments and other organisations often use
the concept of region for planning purposes e.g. allocation of
resources and development of policies. Resources found within
regions mean different things to different people over place and
time. E.g. water in the MDB is used by many different people for
different things. Slide 4 Importance of water in Australia Uneven
distribution of rainfall- unreliable and seasonal Driest inhabited
continent average 480mm rainfall a year Sustainable? Increasing
population and demand. Used for agriculture (75%), pastoral,
industrial, commercial and urban purposes. Australians use
350litres a day compared with Asia and Africa who use 50-100
litres. Slide 5 Domestic use Slide 6 Australias water users
Domestic (cook, clean etc) Environmental (ecosystems, living
species) Economic (growing crops, animals, transportation on water,
HEP) Aesthetic (gardens, fountains, parks, ponds) Recreation (on
and around water) Strategic (nations security and well being)
Spiritual (religious ceremonies) Slide 7 Describe the geographic
characteristics and water resources of the Murray-Darling Basin
region location- SE Australia, entire basin covers a regional scale
of 1 million sq km, distributed across 5 states (SA, VIC, NSW, ACT,
QLD). Source of the Murray located at 1430m in Great Dividing
range, mouth enters Lake Alexandrina and Albert near Goolwa.
Distance- catchment is 1250km wide and 1365km long (1/7 th of total
land size in Australia) Region- the drainage basin of the MDB
Movement- the flow of water is from the north and east to the
south-west, draining into progressively drier regions. Spatial
association- the amount of rainfall declines towards the interior
of the basin. There is a strong Spatial association between the
regions of lower rainfall and increasing evaporation rates. Annual
rainfall average across the basin is 480mm. Of this 94% evaporates,
2% soaks into the ground, and 4% becomes run. Water resources-
irrigation channels, Wetlands e.g. Coorong, Barmah Forest, Lower
Lakes, Hume dam Slide 8 Characteristics continued
Population-approximately 2 million people Climate- average rainfall
480mm, evaporation rate is 4x the rainfall, range of subclimates
Shape- low lying, saucer shaped depression, most elevation below
200m Slide 9 Where does the MDB gain its water from? Distribution
of water resources/ types of water resources in MDB Rainfall
Groundwater Diversions from other basins Slide 10 Rainfall
distribution Turn to page 160 NP. Describe the spatial association
between likelihood of drought and rainfall distribution Slide 11
What is Ground water? Is the form of precipitation that infiltrates
the ground and is stored beneath the saturated zone of the water
table in aquifers. Groundwater is located throughout the MDB,
however it is the quality of water which dictates its use, and rate
of use Not all groundwater is useful. Groundwater contributes
10-15% of the Basins water resource. It is used mostly for
irrigation. The 65% of groundwater taken for irrigation, is taken
from an area covering less than 20% of basin Slide 12 Ground water
Slide 13 Slide 14 Factors affecting groundwater consumption? The
rate of consumption of groundwater grows at about 4% per year. WHY?
Increasing reliance is due to expansion of irrigated agriculture,
drought periods and greater regulation o surface water Slide 15
Diversions- water from outside the basin. Release of water from
Snowy Mountains Scheme into the Murray and Murrumbidgee rivers and
transfers from the Glenelg River to the Wimmera River provide
another 1200 GL per year for the MDB from outside the basin. Slide
16
