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Rainforest Economics
Rainforest Economics
Bifurcated approach to Rainforest Economics
• Ecological economics• Traditional market economics
Ecological rainforest economics
• immense biolog. and geolog. timeframe • Vast, robust biodiversity reservoir
– intrinsic value
• Vast capacity for nutrient banking/recycling– extraordinary reservoirs of living biomass on
some of the poorest soils in the world
• Global/regional/local climate control– precipitation & oxygenation
Traditional market rainforest economics
• Narrow human short-term focus• cultivated products
– coffee, cocoa, bananas, dairy, others
• Tourism / “ecotourism”– hard currency value to indigent
populations– conservation impetus
• animals economically harvested v. “recycled”• Vegetation / habitat preservation
Traditional market economics (continued)
• Rainforest derivative products– more nutritious foodstuffs– genetic library (recombinant DNA
techniques) irreplaceable• example: Tufts University project to clone goat
able to produce goats’ milk w/human blood anti-clotting protein, antithrombin III (FDA approval pending)
• cloning technology three years ago w/sheep ”Dolly”
• “only the beginning”
Rainforest product sources
• Survival mechanisms – Herbivore defenses
• Tissue conservation impetus on poor soils– Amazonian Hevea brasiliensis: rubber– hardwoods, resins
• most common: one Amazonian study revealed– plant biomass at 99.8 % of total ecosystem biomass– animal biomass remaining 0.2 %
» 7 % ate living leaves / stems» 19 % ate dead wood (termites)» 50 % ate dead vegetation» remaining 33 % carnivories
• called secondary compounds, allelochemics: lack metabolic function
Example: caffeine
• stimulant to humans• really an insecticide
– harmful at normal levels found in plants– type of alkaloid
• called methylxanthines
– interfere w/enzymes• e.g. tobacco hornworm
– discourages insect feeding
• other alkaloids have other uses
Example: Cyanogenic glycosides
• passion flora (Passiflora spp.)• cyanide poison
– plant locks cyanide molecule with sugar molecule– when consumed, sugar reacts w/enzymes in herbivore’s
digestive system – leaving hydrogen cyanide– discourages herbivores
• Heliconius spp. Butterfly/caterpillar; able to detoxify– each species can detoxify one or two cyanogenic glycosides– butterflies are selective re Passiflora spp. – specialized hydrolytic enzymes reactive
Rainforest economic relationships
• Case study: Howler monkeys (Alouatta villosa)– Kenneth glander in Costa Rica (1977)– Most monkeys only ate at three of 149 Madera negra
(Gliricidia sepium) trees in area– Others ate at other trees perished– three w/lowest levels of rotenone (rat poison)– speculated that hebivory poisons provide a selection
pressure affecting development of intelligence and social/communication skills in primates
• remembering toxic v. safe trees
– analogy: 149 restaurants, 146 poison customers, 3 safe• we would tend to remember where the safe ones were
similar Human/animal approaches
• humans use toxic rainforest products for beneficial uses
• animals likewise – example: orange monarch (Danaus plexippus)
• milkweed produces cardiac glycosides (digitalis) to discourage herbivory
• caterpillars feed on milkweed • caterpillars accumulate and store digitalis in tissues• after metamorphosis, butterfly toxic to birds
– usually regurgitate, but remember unpalatable
• reason why they can be so beautifully and colorfully marked: like labeling poison for children
Conflict of ecological / market economics
• competing resource uses– land use– water allocation & storage– air (e.g., fossil fuel use)
• paradigm conflict, and irony:– defense creates value– value creates demand– demand can produce overharvesting– overharvesting contributes to extinction– therefore defenses may contribute to extinction
Food products
• Fruits– flavors: chemical defenses/inducements re
seeds dispersal• get seeds to right place• keep seeds out of wrong place
– repellents, antibiotics, odors, ripeners, hormones, colors, germination inhibitors, vitamins, minerals, proteins, fats and carbohydrates
• Coffee, teas (caffeine, tannin)
Common foods and drugs
• from Latin American forests– corn, potato, tomato, peanuts, avocado, cashews,
vanilla, sunflower, bananas, mangoes– quinine, mescaline, and cocaine
• commonality points toward unknown losses due to deforestation– US sugarcane industry saved (75% reduction)from
aphid-transmitted virus by utilizing resistant wild sugarcane variety from Java
– coffee rust infections likewise defeated by incorporating wild germplasm genetic resistance
Uncommon potential foods
• winged bean (legume)– also called asparagus pea– from forest of New Guinea– far more protein that common foodstuffs, e.g.,
potatoes– matches soybean
• once uncommon, now principal crop
• pummelo (fruit)– larger than grapefruit – saline tolerant (intrusion increasing)– US consumes 55 million tons of citrus ann.
Genetic library
• potential applications of recombinant DNA techniques; still in infancy
• insecticides– insects: e.g., termites– plants: daisy (Chrysanthemum
coccineum) produces pyrethrum, the most commercially significant “knock down” insecticide
– called “Lucretia Borgia” of plant world
Genetic library (continued)
• insects may destroy more than one-third of total human agricultural production annually
• synthetic insecticides persistent (DDT)• plant-based insecticides biodegradable
– no bioaccumulation problem• The success of any gene-splicing approach
will be defined by the extent of the available library– devel. insect resistance demands library depth
Medicines
• muscle relaxant (arrow poison) Chondodendron strychnos
• anticancer drug from Tabebuia species patented by Pfizer
• expectorant Cephaelis ipecacuanha– every parent familiar, once cured Louis XIV
from amebic dysentery
• antitumoral drug “pristimerin” Maytenus illicifolia
More on Medicines
• Digitalis from foxglove (Digitalis purpurea)– cardiac glycoside stimulant insecticide– Can be fatal to normal hearts at ordinary plant
levels
• Madagascar periwinkle– drug: “vincristine”– folk medicine discovery– 98%+ remission rate children with
lymphocytic leukemia
Markets for medicines
• Largest derivative (processed) market: USA
• Largest folk remedy market: china• one est. rainforest pharmacological
compounds: $60 billion dollars ann.• One est. commercial medical products
derive from rainforest sources– 7,000 products– number is growing
Significant subpopulation variations
• even within species, plants vary– subpopulations vary, Individuals vary
• e.g., apples vary• e.g., taste of maple syrup can vary among individual trees
• Plant species may not be homogenous globally, regionally or locally
• therefore apparent localized extirpations may in fact be extinctions of individuals with different traits
• idea of species as patches of individuals
Related products
• stimulants:– caffeine– cocaine– pepper
• others– sweeteners (stevioside)– perfumes
Brazil
• name derived from sodium salt brazilien– from the woody tree Caesalpinia echinata
• wide commercial use for purple pigment at time Brazil colonized
• Only about 1% of Brazilian angiosperm species plants examined for chemical compounds– rate of work may not keep abreast of extinctions– localized unknown populations of special
concern• example: snail darter / Telleco dam
Animal harvesting for animal testing
• primates– can be raised in captivity– cheaper to capture wild – 90% utilized are wild
• anecdote: experience of in-house chemist formerly employed at major chemical manufacturer
Risks of Harm
• Extinction cascade– interdependence of species
• extinction of first species may lead to extinction of second
– example: Calvaria major and dodo • seed of calvaria major required abrasion in intestines
of dodo; dodo became extinct over 300 years ago• only 13 individual plants left in wild, all 300 years old• scientist force-fed seeds to turkeys; abraded and
germinated
– simply perceiving such interrelationships is difficult
Electrification in developing nations
• competition with rainforest biomasss for land use– not opting for sustainable use methods– hydroelectric method in rainforest
environments• est.: water flow could yield 100,000
megawatts daily– equal to 5 million barrels of oil daily
• large reservoirs inundate vast tracts of forest
Electrification in developing nations
(continued)• fossil fuel method produces
significant pollution, including acid rain deposition with concomitant effects
• expensive fossil fuels create incentive to use hydro where available
Hydro-electrification example: Lake
Brokopondo– Surinam, 1964
• flooded 570 square miles of rainforest• trees not harvested: take too long, “too
expensive”• decomposing trees produced hydrogen
sulfide, damaging dam hardware and costing $5m in unanticipated capital repairs (7% above project estimates)
• malaria-carrying mosquito breeding grounds enhanced
• water lilies choked out other native species
Contrast: sustainable practices
• Swidden agriculture• Dairy cattle v. beef cattle production
– American Quakers to Costa Rica, 1950s– cut trees but left to rot, recycling nutrients– pastures divided into 30 equal parts
• cattle one day each part, 12 days grazing each part yearly
– became major sources of cheese in central America
Conclusion
• Public policy consensus– sustainable v. unsustainable
• by definition, unsustainable practices must cease
• questions are: – when– what is left when it ceases
• Optimal human beneficial uses– consume rainforest– preserve rainforest