Environment vs Food

Myth

• To feed the hungry we are pushing production onto marginal land– destroying rainforests– causing erosion– poisoning the environment

with pesticides

• Cannot feed the hungry and protect the environment

Environmental Destruction

• 70% of 5.2 billion hectares of ag land is in danger of being turned into desert

• Rain forests will be destroyed in 40 years– At current rates

• Global pesticide use 4.7 billion tons/yr. – 220,000 die each year from

pesticide poisoning

http://whyfiles.org/238earthday/images/brazil_combined.jpg

Amazon Deforestation (purple)

Africa

• Traditional agriculture preserved semi-arid land– diverse mix of crops, trees and

livestock

• 19th century colonists view:– Land is a mine to extract wealth from

• Monoculture of export crops without rotation – quickly depleted soil

• Peanuts, cotton

• Best land for Europeans– worst land for Africans

http://www.hewlett.org/NR/rdonlyres/7C6CC2D1-58A5-4544-B08D-9726E5A35423/0/CottonField.gif

African cotton

Africa

• With independence (1960s)– cash crops needed

• Low prices encouraged more planting

• Livestock displaced to drier lands– increased desertification

• Now pastorialism is equated with poverty

http://children.foreignpolicyblogs.com/files/2007/08/p1.jpg

Agriculture in Africa

http://go-kids.grolier.com/map?id=mtlr001&pid=go

U.S. Soil Destruction

• 30% of farmland abandoned since 18th century– Erosion– Salinization– water logging

• 1/3 of U.S. topsoil has been lost• 1/2 of U.S. pastureland

overgrazed– erodes at high rate

• Export boom in 1970s– increased erosion in Corn Belt 39% – in three years

Dustbowl 1930s

http://www.ehponline.org/members/2002/110-2/dustbowl.jpg

Iowa Topsoil Loss

• 150 years ago– Iowa topsoil was 12-16” deep

• Now is 6-8” deep

• Current rate of loss: – 10-15 tons/acre/year

http://publications.iowa.gov/1745/1/images/Buffer.jpg

Global Soil Degradation

http://www.utafoundation.org/soil_loss.jpg

Rain Forests

• Rainforests 7% of land– 50% of plant and

animal species

• Source of – Beauty

– CO2 sink

– Pharmaceuticals– Chocolate, cashews,

bananas, brazil nuts, cortisone, quinine

http://www.wwf.org.uk/picturelibrary/jpeg350/ra/rainforest1.jpg

Amazon rainforest

Rain Forest Destruction

• In 20th century rain forests depleted 50%

• At current deforestation rates– rainforests will be totally cleared

in 40 years

• Amazon is being destroyed at a rate of 20,000 sq miles/year

http://www.unep.org/wed/2007/english/Photo_Gallery/WED_2007/Zoom/PA0176629.jpg

http://photos.mongabay.com/07/trop_defor_bar-600.jpg

Rondonia, Brazil

• 1980s displaced poor farmers flooded Amazon region– slashed and burned to clear land,

plant crops• Swiden agriculture

– Displaced indigenous peoples

• Most failed after few seasons when land exhausted– Cattle ranchers then moved onto

land

• 1990s: Cattle, Soybeans, Logging destroy forest

http://www.css.cornell.edu/ecf3/Web/new/AF/pics/SlashBurn7.jpg

Slash and burn agriculture

• Rainforest: – rain leaches nutrients from soil

– except those captured by plants

• Forest burned – Ashes rich in nutrients

– Serves as mineral fertilizer

• Farming possible – for a few years

– Then soil exhausted

• Land often used for pasture– Cattle ranchingSlash and burn maize, Peru

http://www.mongabay.com/images/peru/tambopata/Tambopata_1030_5148.JPG

Rainforests of the World

http://www.d.umn.edu/~pask0020/educ5413/mywebquest/Rainforest%20map.jpg

Deforestation: Bolivia

• 80% clearing carried out by large land holders– for cattle, soybeans

• 20% cleared by small farmers

• Thus most of clearing is not to feed hungry

http://www.boliviabella.com/images/bolivia_facts_geography_amazon_deforestation.jpg

Deforestation: Central America

• Most of the tropical rain forest has been affected by:– Logging

– Banana Plantations

– Cattle Ranching

Deforestation: Indonesia

• 1997-8 tropical fires created huge smoke cloud– thousands of square miles

• Fires blamed on poor – clearing land

• Actually, most from – Logging

– plantations http://www.rssgmbh.de/img/projekte/projekte_international/ssffmp3.jpg

Pesticides

• 4.7 billion tons pesticides used worldwide

• 2 billion pounds in U.S. – 25% in California

• Fruits and vegetables

– 30% U.S. use for corn, wheat.

– 25% U.S. use in golf courses and lawns

• Pesticide poisoning in U.S. – 300,000 farmworkers/ yrCalifornia lettuce

http://evolution.berkeley.edu/evosite/relevance/images/pestspray.jpg

US Geological Survey 1997

Pesticides in Developing Countries

• The most harmful pesticides – are banned in U.S.

• Used, made in developing countries– Without much protection to workers

• Used for export fruit, vegetables – About 50% used for appearances

• Not used for staple crops in developing countries– Expensive– Mixed cropping of staple crops less

susceptible

Pesticides in Developing Countries

• Protection for workers low

• Regulations lax

• Toxicity education poor

Mexican girl drinking from pesticide container

Pesticides

• Despite 10x increase in toxicity– crop losses have doubled

from insect pests

• 0.1% pesticides reaches pests. – Rest into environment

Pesticide Treadmill

• Central America increased cotton production – between 1945-1970

• Boom displaced small scale food producers – resulting in unrest, violence

• Boom made possible by pesticide spraying – for Boll Weevil

• At first, sprayed only few times/season

• Insects develop resistance to insecticide– Requires spraying more

http://www.dep.state.fl.us/waste/categories/cleansweep-pesticides/images/Image5.jpg

Pesticide Treadmill

• By mid-1960s were spraying 10 times/season

• Pesticides killed natural insect predators• Eventually spraying 40 times/season

– costing 50% of production

• Cost too high, leading to Bust• Now wasted, eroded soils

– ghost towns

• Cotton boom- bust increased hunger– left economic ruin– environmental devastation

http://www.sciencemuseum.org.uk/antenna/non-toxiccotton/images/cotton.jpg