Feeding the World: Ecosystem Services, Food Production and

Sustainability

Elena M. BennettAssociate Professor, McGill University

The Triple Threat

• 1 billion hungry (1 in 7)• Agriculture a the single biggest cause of

environmental degradation• Anticipated doubling of food production

needed by 2050

Dual ChallengeThe dual challenge of feeding 10 billion people while maintaining a healthy environment will be one of the greatest challenges of the 21st century.

Millennium Ecosystem Assessment 2005

Over the past 50 years, humans have changed ecosystems more rapidly and extensively than in any comparable period of time in human history…

to meet growing demands for food, fresh water, fiber, and energy.

These changes have brought gains in human well-being, but at growing costs to both people and nature

Temperate Grasslands & Woodlands

Temperate Broadleaf Forest

Tropical Dry Forest

Tropical Grasslands

Tropical Coniferous Forest

Mediterranean Forests

Tropical Moist Forest

0 50 100

Percent of habitat (biome) remaining

Habitat Loss to 1990

Source: Millennium Ecosystem Assessment

Percent Increase in Nitrogen Flows in Rivers

Source: Millennium Ecosystem Assessment

85% of consumptive use of water is for agriculture

Agriculture: the source of 1/3 of greenhouse gas emissions

The Balance Sheet

CropsLivestockAquacultureCarbon sequestration

Capture fisheriesWild foodsWood fuelGenetic resourcesBiochemicalsFresh WaterAir quality regulationRegional & local climate

regulationErosion regulationWater purificationPest regulationPollinationNatural Hazard regulationSpiritual & religious Aesthetic values

TimberFiberWater regulationDisease regulationRecreation & ecotourism

Enhanced Degraded Mixed

Bottom Line: 60% of Ecosystem Services are Degraded

Millennium Ecosystem Assessment 2005

Commonly proposed solutions …

… and why they wont work

1. Increase area2. Increase yields

1.3 – 2.6 billion additional hectares needed

1. Increase area2. Increase yields

What can we do about it?

• Acknowledge the problem.

• Invest in revolutionary agricultural solutions.

• Bridge the artificial divide between production agriculture and environmental conservation.

JA Foley. 2009. Yale Environment 360.

Cassidy et al. 2013

Revolutionary Solutions

Reduce the amount of new area or increased yields required by reducing meat consumption.

In the US, 67% of calories produced are fed to animals!

Revolutionary solutions:Increase crop yields strategically

Invest in getting better crop yields in Africa where yields are 1/6 of what they are in climatically similar areas of the world.

West et al. PNAS 2010

Bridge the Divide: Think in terms of all the ecosystem services provided by agricultural

systems

Pay farmers for the value of all of the services they provide: biodiversity, places to recreate, a

landscape we enjoy, clean water, etc.

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FOOD

PEST REGULATION

DEER HUNTING

AESTHETIC BEAUTY

MAPLE SYRUP

WATER QUALITY REGULATION

WOOD

NATURE APPRECIATION

CARBON STORAGE

CLIMATE REGULATION