Measures of the health of the environmentPresentation Transcript
Measurements of the State of the Environment 1 Erosion 2 Salinity 3 Land Clearing 4 Over Irrigation 5 Pests 6 Introduced marine species
7 Loss of river flow
8 Soil Acidity
9 Vegetation loss
10 Greenhouse gas emissions
Water cycle (worksheet)
Erosion Soil erosion is a natural process. Human interaction has in many cases speed up the process of erosion. What have we done to speed up the process? Clearing vegetation introduced species (rabbit, cow, buffalo ) Increased water sheeting
Examples: Beach Creek erosion Dust storm Land slips
Soil erosion removes the topsoil. The removal of the topsoil removes nutrients from the location, which are essential for plant growth and animal nutrition. The soil also clogs up the rivers and creeks, which affects the river wild life and causing lowland flooding. Possible solutions to erosion:
Eradicate feral animals
Plant more vegetation
Monitor sensitive farming areas
Restrict people from access altogether
Restrict actives during sensitive times (winter)
Mostly caused by irrigation and tree clearing. Over irrigation causes water tables to rise, causing water logging and root rot. In dry areas salt is brought to the surface with the rising of the watertable which in turn kills off the plants that cannot tolerate the salty conditions. Solutions?
Plant Salt tolerant trees to soak up water
Pump away ground water
Restrict Land clearing
Change farming practices - Crop rotations
Wild life corridors
Government Regulations to control water usage
Pest Control Pest are animals or plants that interfere with human land use. Can native animals be pest? Solutions?
Kill (shoot, trap, poison)
Introduced Marine Species Many marine species are accidentally introduced. They have arrived in the ballast water of ships. Ships enter ports often only carrying water in their hulls for stability in the water. They then discharge this water (only with many foreign species) into the harbors when loading up with other materials Solutions?
Introduced marine species Northern pacific sea star Asian green mussel New Zealand half crab Japanese Kelp
Treatment of ballast water before discharge
How can this be done?
Loss of River flow Hydroelectricity, irrigation and town water supplies have dramatically altered river flows. E.g. Snowy river (hydroelectricity) West Barwon dam (town water) Murray river (irrigation) Solutions?
Release more water to original water flow.
Soil acidity Is caused by too much fertilizer on crops, legume crops and wet land drainage Solutions?
Lime / Gypsum (costly)
Monitoring fertilizer application
Vegetation Loss Carbon sinks – air quality, trees absorb the carbon from, the atmosphere Affects habitats for birds animals and insects. Water quality and quantity, increases erosion From grazing, housing, logging, mining, crops
Greenhouse Gas Emissions (worksheet) Greenhouse effect: global warming caused by the release ‘greenhouse gases’ that act as a thermal blanket trapping heat. Gases include Carbon dioxide, methane, and CFC’s. All occur naturally but have risen dramatically since the industrial revolution.
Habitat Modification Entire ecosystems can be affected by the introduction of a species or changes to the environment. EG Carp, the damming of rivers or Urban sprawl
Over the past 200 years Australia has:
Cleared the forested areas in half
Introduced hard-hooved animals
Over grazed most areas
Raised water tables by over irrigation and deforestation