Why was deforestation beneficial to creating current societies?
It is a step toward the development of communities, towards economies & trading systems, and towards agriculture.
- NA has benefitted from deforestation, yet we often tell developing countries they can’t have these benefits (hypocritical)
Where historically and currently does deforestation occur?
historically: temperate forests
currently: tropical regions
- not just a shift in forests occurred, but the rate at which these forests are being cut down is speeding up
What defines a forest?
- a closed forest: at least 20% crown cover
- an open forest: 5-20% crown cover
What is crown cover?
It is the percentage of shade when the sun is shining overhead.
What defines deforestation?
Different definitions:
- the complete clearance of forests for agriculture and other uses
- reducing crown cover to less than 10%
- difference between degraded forest & deforestation
What are the two main methods of deforestation?
- Clear cutting
2. Selective logging
What does clear cutting mean?
- a forest harvesting process where entire stands of trees are felled and removed
- it’s aesthetically unpleasing & has negative environmental impacts
What does selective logging mean?
- selected trees are harvested (valuable, mature and unhealthy trees taken)
- creates an uneven-aged stand, so a regular supply is always available
- it minimizes biodiversity loss
- there are some issues when it is poorly implemented
What is happened with the Kalimantan Indonesian forest fires?
- fires are a new risk in this area because of poor management and deforestation
- smoke & haze affects other countries
- large economic costs (billions of dollars)
Describe deforestation in Indonesia
- this area is being deforested faster than anywhere in the world
- cutting/burning down trees for palm oil plantations
- moved families to partake in agricultural activities which takes over indigenous land & causes disputes
What evidence is there for increased risk due to deforestation/forest fires in Indonesia?
- traditional forest conditions (heavy canopy, wet floor, humid, few nutrients in soil) can dry out when deforested causing decomposition rates to reduce which fuels more forest fires
- there are old trees with thin bark that will die if burned (unlike temperate forests) because they have never experienced fire - unnatural for area
- once an area has experienced forest fires, it is more likely to experience it again
What are the sources for forest fires in Indonesia?
All human induced!
- conflicts over land tenures (fire as weapon)
- indigenous burn palm oil plantations
- farmers regularly burn crops & use nutrients
- majority come from plantations, forestry & logging
- occurrence of El Nino
Who was blamed for forest fires?
Indigenous! This way it removes the government responsibility & supports future economic activity
What distinguishes old age trees?
- large for species/site
- wide variation in sizes & spacing
- accumulation of large, dead, fallen and standing trees
- multiple canopy layers
- root decay
Why are old growth trees valuable?
- high value lumber
- stores lots of carbon
- high genetic diversity
Why does logging affect ecosystems?
- changes the ecosystem structure and affects biodiversity as natural viability is reduced when plantations are created
- clear cutting drastically changes the landscape which can cause certain species to suffer (i.e. caribou)
How can clear cutting be beneficial?
- gives an ecosystem the chance to regenerate & species diversity can rapidly increase
- species like deer benefit from small clear cut areas
- cost-effective (fast, easy access, most value)
How does forest harvesting affect site fertility?
- harvesting forests removes nutrients
- not all sites can quickly recover
- nutrient loss is reduced when trees cut in winter (no leaves)
How does forest harvesting affect soil erosion?
- heavy precipitation & slopes means more erosion
- trees hold soil in place, so without higher risk of erosion
- poor road designs can impact too
How does forest harvesting affect the hydrological cycle?
- tree removal reduces storage capacities of water and can result in flooding
How does forest harvesting affect climate change?
- forests carbon sink, but turn into a carbon source when decomposed/burned (can significantly alter CO2 levels)
What are the disadvantages of clear cutting?
- nutrient loss from ecosystem
- loss of habitat
- erosion
- no timber products available for long periods of time
