Overview: The Process of Land Cover Change Flashcards
(22 cards)
1
Q
Define Deforestation
A
- permanent removal of trees and often associated vegetation for non-forest uses
2
Q
Deforestation: Natural Processes
A
- fires, disease, climate change
- large scale climat changes –> reduce rainfall levels –> trees cant survive –> savanisation or desertification of drying areas
eg. sahel in africa
3
Q
Deforestation: Human Activity
A
- began in pre history with clearing of land for gardens and burning forests for hunting (Slash and Burn clearing)
- 30% of Deforestation in South America
- carried out by traditional societies
- rate has increased with population and technological advances
4
Q
Location of Deforestation
A
- rate highest in tropical forests in developing countries (Brazil, Bolivia, The Congo, Indonesia)
- drivers: logging tropical rainforests for timber, land clearing for agriculture, urban development and mining
5
Q
Types of deforestation
A
- clear cutting (removal of all the trees in an area) or selective logging
6
Q
Rate of Deforestation
A
- 2015 > 2020, rate = 10 million ha/year down from 16m ha/year in 1990
- area of primary forest decreased by over 80m ha since 1990
- only 22% of og forest cover remains
7
Q
what are the effects of deforestation
A
- increase rate of biodiversity loss
- land degradation reduces the GHG absorbing capacity of forests
8
Q
what is expansion of agriculture
A
- the removal of valuable forest ecosystems/destruction of other natural biomes
9
Q
Whats the predicted outcome for the expansion of agriculture
A
- estimated globally there will be 18% more land converted to agriculture by 2050 –> from clearing third of remaining forests and grasslands
10
Q
where is the expansion of agriculture most common
A
- primarily occurs in LEDC’s
- Brazil, Bolivia, The Congo, Indonesia, Madagascar
11
Q
What is the intensification of agriculture
A
- increase in the productivity of land already use for agriculture through more inputs in hope for increasing the outputs received
- limited land -> more efficient methods of farming necessary for food security in future
- comes with environmental costs
12
Q
What is the Green Revolution
A
- rapid advancements in the intensification of agriculture during second half of 20th century
New tech: - agrichemicals (pesticides, herbicides, insecticides, fertiliser)
- Machinery (tractors, irrigation systems)
- genetically modified crops (rice, wheat, maize)
Created large increases in yeilds
eg. China agri land increased by 11% but food production increased by 420%
13
Q
drivers of the expansion and intensification of agriculture
A
- increasing population/increasing demand for food
- 1961 –> 1996 global food production double and arable land only increased by 10%
14
Q
Define Urban sprawl
A
- refers to the outward expansion of the urban area, usually in low, density, and often uncontrolled manner
eg. slums
15
Q
Urban Land Cover
A
- 1% –> 3% of earth’s surface
- small area but urban anthrome is completely changes from the environments natural state
- greatest influence on global land cover
16
Q
Population of Urban areas
A
- 56% of world pop and increasing
- 2045: people living in cities will increase by 1.5 times to 6 billion adding 2 billion
17
Q
Impact of Urban sprawl on land cover
A
- natural veg or agriculture land is replaced by roads, houses, and other urban infrastructure
18
Q
what are the drivers of Urban sprawl
A
- unorganised expansion
- increased immigration
- rapidly increasing populations
19
Q
Where does urban sprawl take place
A
- expected to take place in small, medium sized cities of a million or fewer inhabitants (UN 2010)
- World will add aprox. one new city of a million people every 5 days until 2050
- most growth occuring in china and india
20
Q
Mining land cover
A
- takes up about 1% of land surface
- surface mining: vegetation and soil removal –> scrapes in the surface or large open cut pits
- changes shape of earths surface
- mining also effects land cover through use and release of chemical, dust and aerosols
21
Q
Mining post industrial revolution
A
- land area under mining has increased
- further growth as dd for manufactured products and energy increases with econ expansion increasing levels of development and urbanisation
22
Q
Describe the land clearing in order for mining
A
- encourages other land users to move in as increased roads and infrastructure
- major cause of the deforestation in the amazon rainforest
- some countries have strict regulations of the mining industry that require significant efforts to rehabilitate the land cover after mining
eg. australia
