exam cards 135 Flashcards
what are the four broad categories for deserts
Polar, Subtropical, Coastal, Cold
How many goals does the agenda 21 have
17 goals
What does agenda 21 refer to
a global agenda for the 21st century
what % is the total world land forest
30%
what % is total world land drylands
40-45%
definition of a desert
Extremely arid at least 12 consecutive months without rainfall
What type of system does the USA use to approach to sustainabilty
“country led”
What is a bottom-up approach and give a example of one
goals set for the individual citizen to follow, local agenda 21, think global act local
when was the millennium summit
2000
what was the pairs agreement
In effect once >55 countries that produce >55% of greenhouse gases are ratified, Every country should set targets to reduce emissions, like the UK’s car emission 2035
list the layers of forest from top to bottom
emergent layer, canopy cover/drip cover, understory, forest floor
List five countries, that make up half of the forested land
Brazil, Russia, China, Canada, United States of America
list the type of forests
open forest (over 40% covered, usually tropics), closed forest (10%-40% covered, Boreal), other wooded land (less than 10%, subtropical)
definition of deforestation
“Deforestation is the conversion of forest to another land use OR the long-term reduction of tree canopy below the 10% threshold.”
list some deforestation stats
Deforestation: temperate (35%) > savannah (25%) > rainforests (5-10%), Perhaps 90% of deforestation happened before 1950
what is the main reason for deforestation taking place
Creating agricultural land to grow crops (e.g. soya, palm oil) or pasture for animals
list methods of deforestation
logging (people manually cutting trees), Fire (lighting fires to burn the wood and plants over a large area), dieback (climate change)
list some of the effects of deforestation
- C cycle, local & global climate change
- Degradation of land quality, fertility
- Soil erosion by splash erosion, and exposure to wind, increased dust storms
- Impacts of fires
- Effects on biodiversity, forest edges
- Impact on the local and global water cycle and evaporation
- Increased flooding especially along marine and fluvial coastlines
- Increased hunting, catching and selling of animals, along with illegal logging
- Impact on land stability, giving more landslides
estimate carbon store with living trees globally
300 billion tones
impact on soils deforestation has
- Forests associated with very low erosion rates
- Loss=>Degradation, less organic matter, (higher T, absence of shade).
- Prime causes of soil erosion ARE deforestation and agriculture
Soil erosion costs world $400 billion per year
Biological Impacts of Deforestation
- Habitat loss and food sources
- Biodiversity reduction including species not yet discovered
- Injuries to animals from burning wood.
Isolation of species by breaking down migration routes
definition of Afforestation
“The process of sowing seeds or planting trees in an area that does not have trees to create a forest…. The conversion of bare or cultivated land into forest.”
definition of Reforestation
The process of re-establishing forest formations after a temporary condition with less than 10% canopy cover.
list the benefits and Disadvantages afforestation
Benefits of Afforestation:
- Enable the creation of an alternative source of timber and timber materials
- Enable growing certain types of trees
- Developing new ecosystems and enhancing biodiversity
- Reduce land degradation and soil erosion
- Improve air quality
- Carbon capture and storage.
- Reduce floods
Disadvantages of Afforestation:
- Monoculture trees are more susceptible to pests
- Biodiversity is associated with mature forest
- Negatively affect original ecosystems
- Driving up food prices while taking land from agricultural processes
- Introduction of invasive and non-native species
Use a large amount of land and water resources
