Unit 2, Outcome 1 DISCOVERING OUTDOOR ENVIRONMENTS
2.1.1Types and characteristics of selected outdoor environmentsAustralians are the custodians of some of the most diverse ecosystems on the planet. Our continent is one of the worlds 12 biologically mega-diverse regions, with a high proportion of endemic species those that are found nowhere else in the world. For example, 93% of our marsupial species and 88% of our native rodents are endemic.
Victorias land area supports a wider range of broad ecosystems than any area of a similar size in Australia: Alpine, marine, coastal, heathlands. wetlands, grasslands, forest and arid.
Each have specific features/characteristics that make them unique and different from others.
These environments support at least 3140 native species of vascular plants, 111 mammals, 447 birds, 46 freshwater and 600 marine fish, 133 reptiles, 33 amphibians and 750 mosses.This richness in the number of different ecosystems and different species, and the genetic variety they exhibit is what we call biodiversity.
KEY CONCEPTVictoria contains a variety of natural environments that have evolved and developed over millions of years.
KEY CONCEPTThe specific type of environment you find yourself in in dependent on a number of factors.
These include:Geology ClimatePosition & Aspect
Factors affecting natural environments.
Complete a table in your workbook like this: Summarise the environmental influences of each factor from the following slides
Factors affecting natural environments:Environmental influences of each factorGEOLOGYCLIMATEPOSITION AND ASPECT
The influence of Geology can be seen in an area by the type of rock found there, the soil characteristics and drainage.
Soil changes occur through the parent rock, the elements (wind/rain/sun), living and decomposing plants, and groundwater.
The shape of the land (topography) is also important, such as is found at the Cathedral Range (upswept rocks).
Annual rainfall, extremes in temperature, and average daylight hours are examples of climatic factors that can affect a landscape. HOW?
Other aspects include wind patterns, evaporation, ground temperature, frost frequency and snow cover.
Australian rainfall is seasonal and erratic, producing extended periods of drought.
POSITION & ASPECTGeographic location is very important when determining the development of environment types. In physical geography, aspect generally refers to the horizontal direction to which a mountain slope faces.
Aspect can have a strong influence on temperature. This is because aspect affects the angle of the sun rays when they come in contact with the ground, and therefore affects the concentration of the sun's rays hitting the Earth.
The aspect of a slope can make very significant influences on its local climate. The sun's rays are in the west at the hottest time of day in the afternoon, in most cases a west-facing slope will be warmer than a sheltered east-facing slope
In Australia, remnants of rainforest are almost always found on east facing slopes which are protected from dry westerly wind.
In eastern Australia, southerly and easterly aspects receive:- Lower radiation loads, resulting in reduced water-loss- Are fire protected, thus permitting the survival of rainforest species.
Environment types in Victoria
Dry forest & woodlands
Dry forest & woodlandsThe Great Dividing Range forms a barrier across Victoria. It protects many north-facing slopes from the cool/moist winds sweeping from Bass Straight.This results in the northern foothills being relatively dry.
Different forest ecosystems include:Stringybark forests (these dominate the near-coastal landscape east of Western Port)Red gum forests survive along major rivers in the north of the StateBoxIronbark forests lie in a wide arc from west of Stawell to east of Wangaratta
Box-Ironbark forestRed-Gum Forest
Stringy Bark Forest
Dry forest & woodlandsMost of the dry forest & woodlands that would have been found are now gone due to clearing.Dry forests and woodlands are biologically diverse and support a variety of plants and animals, included some vary rare flowers and birds.Habitat modification, vegetation clearance, weed invasion, feral predators and loss of hollow-bearing trees are significant concern.
Arid and semi-arid areas
Arid and semi-arid areasApprox. 4 million yrs ago, a vast inland sea covered what we now call the Mallee and the north-western part of Victoria. This has left this area with a legacy of sand and shallow soils that cover the area today.
The area is dominated by low Mallee scrub and small eucalyptus that can withstand prolonged dry periods and harsh conditions.
The flora and fauna in this place is remarkably diverse this being an area that seems very lifeless.
GrasslandsPrior to European settlers arriving in Victoria, extensive grasslands covered the plains between the Murray Valley and the Great Dividing Range
Indigenous people had used fire in the past to maintain the open nature of the landscape.
These grasslands contain a variety of floral species, kangaroo grass, wallaby and spear grass.
This environment attracted Europeans for uses in cattle grazing, cropping and pasturelands.
GrasslandsAs a result of these things listed, less than 1% of Victorias native grasslands remains intact today. These areas are however in very small areas and therefore face the risk of weed invasion, salinity and urban development.
HeathlandsHeathlands are found within Vic from the Coast to the mountains.Characteristically a low and shrubby environment, trees twisted by the dry winds they are typically subjects to.
HeathlandsNutrient levels in the soil are generally low, and the soils are also acidic. These areas have a close relationship with fire, some plants needing this to re-germinate. The grass tree is one example. (Xanthorrhoea australias)
HeathlandsThese environments are dominated by hard-leaved plants such as banksias, bottlebrushes, tea trees and eucalypts.As their name suggest they are also populated by a number of heaths.
Wet Forests and RainforestsVictorias wet forests and rainforests are found in southern, central and northeast regions of the state. They include the Otways, Wilsons Prom, and the Alps .The worlds largest flowering plant (the Mountain Ash) occurs in these ecosystems.
Wet Forests and RainforestsOther plants/trees include manna gum, messmate stringybark, mountain grey gum, Blackwood, and various tree ferns.Several rare mammals including possums and birds require hollow trees to nest and habitat. Many forest plants have adapted well to fire and can re-establish them afterwards, however rainforest plants have not adapted well and can reduce significantly after a fire.
The Alps (Alpine)The word Alpine is often used to describe any high mountain area. Theoretically, the term refers to the area above a certain altitude where there are no trees because of prolonged cold.
Snow covered areas of Australia cover approx 0.15% of the country (11,700 square kms).
Mt Kosciusko is Australias highest peak (2228 m) and Mt Bogong is Victoria's highest (1986 meters).
The Alps (Alpine)Aust. Alps have eroded over 500 million yrs, unlike others around the world. This has formed rounded mountains and plateaus.
Sphagnum moss is a very unique vegetation that has adapted to suit the Victorian Alps. Bogong High Plains
The CoastVictoria has over 2000 km of coastline
It ranges from sheltered bays and inlets to rugged eroded cliffs. The west coast is sometimes exposed to gale forced winds that have contributed to the amazing scenery along the Great Ocean Road.
The coast is constantly changing due to the relentless effects of the wind, rain and waves.Some factors that influence coastal vegetation are related to wind, salt and natural land instability.
The CoastDunes are held together by grasses and herbs, while salt marsh and mangroves inhabit the mudflats.
These plants play a crucial role in holding the subsoil together in these environments.
Birds are the most common types of fauna in this environment, ranging from Fairy Penguins to a large number of migratory birds from Siberia, Japan and the North Pacific Ocean.