Processes of land cover change Flashcards
Identify the processes of land cover change
Growth of urban settlement and urbanisation
Deforestation
Land reclamation
Expansion and intensification of agriculture
Land and soil degradation
Rangeland modification
Industry and mining
Irrigation
Growth of urban settlement and urbanisation
-Urban growth is a population increase in urban settlement
-Urbanisation is a population shift from rural to urban areas
-Cover 3% of the world’s land and contain more than 50% of the world’s population
-Urban area can affect climate because they change the colour and smoothness of land surfaces thus affecting the heat budget and the water cycle through changes in the transmission of heat, water, albedo and radiation as well as vegetation cover
-Cities also impact on wind flow, air quality, temperature, cloud distribution and rainfall
Deforestation
-Refers to the removal or clearing of forests generally for other uses such as agriculture and urban development
-Different types: fires, clear-cutting for agriculture, logging for timber and degradation from climate change
-74,000km+ are removed every year, with Brazil having the highest level of deforestation
Land reclamation
-Where land is gained or created from the sea, wetlands or riverbeds
-One of the largest examples of reclamation is the Flevopolder in the Netherlands which is the largest artificial island in the world
Expansion and intensification of agriculture
Expansion of agriculture
-Refers to increasing the amount of land available which can be used for agricultural activities; this can involve deforestation or other vulnerable land being cleared
-There is little undeveloped farmland left and much of the remaining land is either desert, ice, or forest
-E.g., Indonesia with their palm oil production
Intensification of agriculture
-Refers to increasing the productivity of the resources already being used in agriculture
-Occurs by maximising the output by adjusting: labour, fertilisers, pesticides, capital, technology, etc.
-This has occurred as the land available for the expansion of agriculture diminishes
-Agricultural intensification has increased pressure on the environment and the natural resources
Land and soil degradation
-Land degradation is the decline in the quality and health of natural land resources, this includes soil degradation
-Occurs due to overgrazing, excessive tillage, erosion, sediment disposition, mining, urbanisation, disposal of industrial waste, road construction, decline of plant communities and the effects of noxious plants and animals
-Estimated that since 1960 1/3 of arable land has been lost through degradation
Desertification
Desertification occurs if there is continual degradation in a dryland ecosystem, usually caused by unsustainable use of land resources or climate change and can be avoided through land management
Rangeland modification
-Rangelands are lands where the native vegetation is predominently grasses, grass-like plants, savannahs and shrubs
-Roughly 80% of Australia can be defined as rangelands - ‘the ‘Outback’
-Rangeland ecosystems are under threat due to the expanding agricultural use of them and the introduction of weeds and exotic species; this impacts the ability of the rangelands to provide ecosystem services to the population
Industry and mining
-Mining is an important industry for many countries such as Australia
-Australian mining processes are very regulated, in some countries they’re not
-E.g., Venezuela and illegal gold mining which threatens their river systems due to the erosion caused through their mining practises
Irrigation
-Irrigation is an artificial method of watering plants for agriculture; it involves diverting waters from streams, flooding areas like rice paddies or the use of pumps anf sprinklers from ground water
-Issues of water rights can arise when regions or countries share water resources especially if water use in one area impacts areas down stream
-Areas of high irrigation density can be found in the Murray-Darling River basin in Australia
