geographic characteristics of sub regions in the mdb

Geographic Characteristics of sub regions in the MDB

Sub Regions in the MDB

Key Skills and knowledge

•Definition of a region

• Identification and classification of selected regions

The upper Darling• Majority of Australia's Cotton Industry

• 91% located along tributaries of the upper darling

Balonne River

Upper Darling

The Lower Darling

• Arid

• 6 million Hectares

• Native Vegetation (Mallee, salt bush, red gum)

• Mungo National Park, Walls of china, Willandra

lakes World Heritage Area provide records of

Indigenous life

The Lower Darling cont..

Mungo National Park Wine grapes

Menindee lakes store water for irrigation and for Broken hill Pleistocene human footprints –

Willandra Lakes

Lower Darling Cont…

Produce Includes • Wheat• Cotton• Vegetables • Wool • Meat• Wine grapes• Stone fruits• Apples

The upper Murray

• The Murray begins its 2375 km journey

• three springs south of Mt Kosciusko

Upper Murray cont…

The Hume Dam

• This sub region makes up less than 2% of

the Murray Darling catchment

• But contributes 37% of the rivers total

flow• Hume and

Dartmouth Dams control flow and generate hydro electricity

The Riverine Plains

• Flat

• Sediment eroded from

the Great dividing

Range and deposited

• Cadell tilt block changed the course of the rivers and helped produce Australia's largest red gum forest (Barmah)

Riverine plains cont…

Barmah Forest

• Barmah forest occupies 60 000 hectares

• Shepparton and Cobram orchards produce

80% of Australia's canning fruit • Rice is grown in

Deniliquin and Wakool regions

The Mallee zone and the Riverland / Sunraysia region

• Murrumbidgee and

Darling rivers join the

Murray

• Semi Arid region

• Sandy soils, dunes, slat

lakes, shrubs, sparse

distribution of trees

The Mallee, Riverland, Sunraysia region cont…….

Confluence of Murrumbidgee and darling rivers

• Ancient sea deposited large amounts of

salt, present in soil and ground water

• Extensive Irrigation allows:• Grapes• Citrus fruits• Stone fruit• Flowers• Vegetables

The Murray Gorge• River has cut through

Hard limestone

• The Valley is 1.5 -2 km

wide

• 30 – 40 meters deep

• Vertical cliffs and

elongated wetlands

border

The Murray Gorge cont…

• The gorge is approximately 280 km long

• The regional water table and river

intersect

• Salty water enters the river through

aquifers exposed in the cliff face

• The river turns sharply at Morgan

The lower Murray, the lower lakes and the Coorong

• Wetlands have been

drained and reclaimed

for pasture and dairying

• At Goolwa, barrages

prevent salt water from

extending upstream

The lower Murray, the lower lakes and the Coorong cont….

• The barrages also keep water levels high

enough for irrigation

• The river enters the lower lakes and finally

the southern ocean

Mouth of the Murray and the Coorong

The Coorong

• Some water flows into the Coorong

• The Coorong is a 140 km lagoon behind

the coastal dunes