Feeding the World:
Ecosystem Services, Food
Production and Sustainability
Elena M. Bennett
Associate 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 Challenge
The dual challenge of feeding 10 billion people
while maintaining a healthy environment will be
one of the greatest challenges of the 21st
century.
Over the past 50 years,
humans have changed
ecosystems more rapidly and
extensively than in any
These
changesperiod
have brought
comparable
of time in
gains in human well-being, but
human history…
at growing costs to both
people
and
naturedemands
to meet
growing
for food, fresh water,
fiber, and energy.
Millennium Ecosystem Assessment 2005
Habitat Loss to 1990
Mediterranean Forests
Temperate Grasslands &
Woodlands
Temperate Broadleaf Forest
Tropical Dry Forest
Tropical Grasslands
Tropical Coniferous Forest
Tropical Moist Forest
0
50
100
Percent of habitat (biome) remaining
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
Enhanced
Crops
Livestock
Aquaculture
Carbon sequestration
Degraded
Capture fisheries
Wild foods
Wood fuel
Genetic resources
Biochemicals
Fresh Water
Air quality regulation
Regional & local climate
regulation
Erosion regulation
Water purification
Pest regulation
Pollination
Natural Hazard regulation
Spiritual & religious
Aesthetic values
Mixed
Timber
Fiber
Water regulation
Disease regulation
Recreation & ecotourism
Bottom Line: 60% of Ecosystem Services are Degraded
Millennium Ecosystem Assessment 2005
Commonly proposed solutions …
1. Increase area
2. Increase yields
1.3 – 2.6 billion
additional hectares needed
… and why they wont work
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.
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!
Cassidy et al. 2013
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.
CLIMATE REGULATION
AESTHETIC BEAUTY
`
MAPLE SYRUP
CARBON STORAGE
NATURE APPRECIATION
WOOD
DEER HUNTING
PEST REGULATION
FOOD
WATER QUALITY REGULATION