QCAA Geography Land cover transformations and climate change

Answers could include:

For type of land cover change:

• growing global affluence has led to greater consumption of meat and dairy products, expanding and intensifying agricultural land use and the removal of remnant vegetation
• growing global affluence has driven greater demand for raw materials, contributing to greater land cover change in the form of mining and the removal of remnant vegetation.

For rate of land cover change:

• growing global affluence has rapidly accelerated the area of land being cleared for meat production particularly in developing countries
• growing global affluence and subsequent urbanisation has led to a high rate of urban fringe areas being cleared for urban development.

Answers could include:

Anthropogenic environments are the result of sustained direct human interactions with ecosystems and include agricultural, mining and urban areas.

For climate change:

• increases in rainfall variability in agricultural environments, resulting in increases in droughts in rural areas will lead to lower crop yields or failures, and collapse of vulnerable ecosystems
• increasing intensity of rainfall patterns in agricultural environments resulting in flooding of rural areas will lead to the displacement of people and reductions in agricultural outputs
• an increase in heat stress and in vector borne diseases in urban environments will increase health risks and death
• sea level rise near urban environments resulting in permanent flooding, tidal inundation and increases in storm surges will lead to loss of urban land.

Answers could include:

Strategies selected can address impacts of land cover change including:

• changes to the water cycle
• soil erosion and/or degradation
• loss of habitat and biodiversity
• loss of ecosystem services
• urban heat islands
• the degradation of aquatic and/or marine environments.

Examples of specific strategies include:

• Yarra Yarra Biodiversity Corridor
• Dirk Hartog Return to 1616
• Beeliar Wetlands Restoration
• Gondwana Link
• Perth and Peel Urban Greening Strategy
• Drains to Living Streams.

Answers could include:

For soil erosion:

• natural vegetation is removed for agricultural purposes. Rainfall hits the bare ground and compacts the soil before running off. The runoff washes the topsoil containing nutrients away. Runoff also deposits soils in other areas such as waterways and causes gulley erosion which may render the area unusable for agriculture. For example, in Western Australia the annual cost is approximately ＄10 million in lost production

For loss of habitat and biodiversity

• natural vegetation is removed for agricultural purposes. Areas can be preserved but these are generally fragmented and too small to sustain ecosystems leading to biodiversity loss. For example, threatened mammals in Australia have decreased by 41% since 2000. Loss of habitat and biodiversity reduces ecosystem services such as carbon sequestration which mitigates the effects of climate change and reduces pollination services which are required in agriculture

For urban heat island

• warming of temperature in an urban area, relative to its rural surrounds due to the removal of natural vegetation. Man-made surfaces including concrete, dark roofs, asphalt and roads which absorb sunlight and radiate that energy as heat, creating a warming effect. For example, some outer suburbs in the newer growth zone of Perth, such as Alkimos, can be up to 3° hotter than the surrounding rural areas.