year 11 module 1 : kooragang wetlands Flashcards
what is ash island?
an estuarine wetland
where is ash island located (4)
32° 52’ S, 151° 47’ E
Hunter region
160 km north of Sydney
15 km north west of Newcastle CBD
how is a wetland defined
any area completely, temporarily or periodically covered by fresh or salt water of a depth up to 6 m.
what influence lead to ash island become a estuarine wetland
ash island is influenced by ocean tides as a salt water source and the hunter river with it’s fresh water this leads to the creation on the estuarine wetlands
what is spatial dimensions
where and why an environment is there
what does ecological dimension mean
the relationship between humans and the natural environment
what where the different eras of ecological dimensions on ash island (6)
pre-European era getting timber era Scott Era Farming Era Industrial Era Environmental Era
what happened during the pre European era
the Awabakal and Worimi people conserved and co existed with the environment, and therefore had minimal impact ,as they took a precautionary approach by only hunting and gathering
what happened in the getting timber era
in 1797 20 years after European colonisation. the land had been completely exploited for the value timbers of the red ceder and ash trees. leading to extinction of many species and of flora and fauna in the area.
what happened during the Scott era(2)
the Scott family lived on ash island during this time and where naturalists and conservationists, who established gardens and protected the ecosystem’s vegetation.
The daughter Helena was an artist and recorded 240 species of plant which has guided in today’s rehabilitation.
what happened during the farming era(2)
In 1955, 17 dairy farms were created through the clearing of land which further degraded and reduced biodiversity.
water pollution became extreme due to chemical runoff from fertiliser and cows grazed on the salt marsh causing them to become endangered
what happened during the industrial era
kooragang (ash) Island was intended for industry in the late 1900’s, and due to the construction of roads like Tomango road, salt marshes had been placed in emense stress as it stopped water flow allowing higher water levels leading to salt marshes to rise.
what is happening during the environmental Era
The kooragang Rehabilitation project in 1993 aimed to rehabilitate and create fisheries, prove the opportunities for research, education and tourism and co-exist with the wetland.
what are some things the kooragang rehabilitation project have done.(4)
conserve the ecosystem
riverbank protection
replanting of native plants (180000 trees)
city farm is used to show that agriculture and the
-environment can live in harmony
what is the RAMSAR Convention on Wetlands (1971) purpose
aims to halt the worldwide loss of wetlands and to conserve through wise use and management, through
which criteria does ash island meet to be classified under the RAMSAR Convention.(3)
criterion 2: the hunter estuary wetlands site supports vulnerable or endangered species.(E.g. estuary stingray)
criterion 4: the area houses 112 species of water birds and 45 species migratory birds that are under the international agreement
criterion 6: the area regularly supports 1% of the flyway population of the eastern curlew and the red-necked avocet.
what influence does the atmosphere have on the inter-tidal wetlands (4)
Climate – subtropical, warm, wet summers, mild dry winters.
Winds: summer NE breezes, worst wind from the west and south.
Air pollution – great potential air pollution from industry but because of the position of the industrial area in the SE, allows winds to blow it away.
Heat Islands – water is present in most places (moderating), although there are some very localised temp variations due to aspect and % of canopy cover.
what influence does the hydrosphere have on the inter-tidal wetlands (6)
Tidal flushing (twice daily)
Flooding from the flow of water down the Hunter River catchment.
Sedimentation – great build-up in river especially North Arm (80% flow) due to natural curve, river bank erosion and deposition downstream.
Water pollution – potential problem
Algal Blooms – haven’t been a prob because of tidal flushing, but have been further up catchment e.g. Williams River
Waste disposal – dumping of liquid waste and solid waste dissolving in the river (EASY TARGET)
what can cause water pollution in inter-tidal wetlands on ash island(4)
Industry in Hexham area
Urban run-off (fertilizers and pesticides)
Accidental oil spills
Flood tide (incoming) dispersal of pollution from downstream industry during time of low flow
what influence does the lithosphere have on the inter-tidal wetlands. (3)
Over thousands of years the sediment carried down the river build up in the estuary to form a series of islands
The Ash Island soils are not surprisingly alluvial in nature, but due to the deposits of limestone beds, from seashells, that was extensively mined late last century
Topography – very flat around 2 m above sea level
what adaptations do mangroves have to survive in inter-tidal wetlands(7)
pneumatophores long extended roots Bottom side of leaf excretes salt fine hairs waxy cuticle floating seeds
what causes mangroves in inter-tidal wetlands to adapt(2)
natural stress from
salinity :makes plants dehydrated
tidal movements: make ground anoxic, which means gaseous exchange can not happen
what do pneumataphores do
they are scuba like roots that allow gaseous exchange
what do long extended roots do
gives the mangrove trees stability in the soft soil
