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APS278 Tropical Forest Ecology & Conservation > managing farming to reduce biodiversity loss > Flashcards

Flashcards in managing farming to reduce biodiversity loss Deck (13)
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1
Q

How is agriculture expanding in the tropics?

A
  • expanding globally
  • 154 million hectares converted between 1980-2012
  • rapidly expanding human population
  • meat consumption growing
  • but get 16x more protein per hectare from soy than beef
  • more biofuel use (more US corn for biofuel than animal feed)
  • production could grow 60-100% in next 40 years
  • palm oil 56%
  • soya 33%
  • cocoa 32%
  • sugarcane 26%
2
Q

What are the biological costs of conversion to agriculture?

A
  • massive loss of diversity
  • usually loss of abundance
  • systems vastly simplified by conversion
3
Q

What is land-sharing vs land-sparing?

A

Land-sharing:

  • farm at lower intensity
  • organic farming
  • set aside strips
  • woodlots/fragments
  • biodiversity protected within agricultural matrix

Land-sparing:

  • farm at high intensity
  • industrial farming
  • use less land to meet demand
  • biodiversity protected within remaining natural forest
4
Q

Is land sharing or sparing best?

A
  • calculate species abundance across land scape
  • density yield curves
  • if convex (bends in on itself) land sparing best
  • if concave (bends out) land sharing is best
5
Q

Which strategy is better for species?

A
  • land sparing is best in oil palm (Phalan et al., 2011)
  • especially for species with small ranges
  • previous work ignored potential role of surrounding landscapes (e.g. dispersal from/resource utilisation of areas outside test landscape (source-sink dynamics)
6
Q

What is the impact of landscape configuration (land-sparing/land-scharing)?

A

Gilroy et al., 2014

  • focus on cattle farming in Andes
  • sample birds in cattle pastures and forest
  • sample at range of distances from contiguous
  • land-sparing is best for biodiversity
  • more species have higher abundance
  • higher landscape-level species richness
  • increasingly better from contiguous forest edge
  • also best for carbon
  • we should intensify existing tropical farmland, not clear more
7
Q

How would expanding in low biodiversity areas?

A
  • many areas already degraded in the tropics
    e. g. burned multiple times, erosion, converted to farmland

e. g. Imperata grasslands in SE Asia
- 2020 oil palm demand could be reached in focus on degraded lands

8
Q

What’s the effect of oil palm & pasture?

A
  • species richness differs
  • species composition
  • forest species decline
9
Q

What should we conclude about agricultural conversion of tropical forests?

A
  • forest patches have most species
  • oil palm more species rich than pasture
  • forest species have higher occurrence in oil palm than in pasture
  • minimal biodiversity impacts of converting intensive - Llanos pasture to oil palm
  • but vital to preserve forest patches
  • how can we persuade the oil palm industry to direct development to such areas?

sustainability (‘green’) labelling

10
Q

What is sustainability (“green”) labelling?

A
  • media & consumer pressure
  • e.g. greenpeace campaigns: killer vs kitkat
  • 400 global retailers to worth $2.8T cut all deforestation from supply chains by 2020
11
Q

What is the cost of removing deforestation from the supply change?

A
  • to meet 2025 production need for oil palm
  • simulate where to ut new oil palm to avoid deforestation
  • calculate rent of current land use
  • predict oil palm rent
  • choose most profitable cells
  • increases production cost by $30 per tonne
  • e.g. increase in mars bars cost for 0.0001p
  • demand deforestation free products!!!
  • caveat: not enough forest free areas to meet demand beyond 2025
12
Q

What are the pros/cons of high yielding crop varieties?

A
  • more crop per hectare
  • Sime Darby “superpalms” 10 tonnes of crude palm oil per hectare vs usual 4
  • genome sequencing opens way for producing pest & drought resistance
  • big potential for saving forest

BUT

  • markets are globally interconnected
  • buyers can substitute one crop for another: 53% oil palm yield increase would lead to 4.3% price fall
  • transfer of food production from temperate to tropics & leading to more deforestation
  • need government to zone areas for high yielding crops coupled with forest estates
  • without this safeguard, land sparing could be in the temperate zone
13
Q

summary

A
  • expansion of tropical farmland is the biggest driver of global extinction crisis
  • growing demand means production may double by 2050
  • land sharing vs land sparing paradigm
  • sparing best, but need adequate safeguards
  • degraded (non-forest) areas can be used
  • sustainability to access western markets
  • effective land zoning to stop deforestation