Download Evolution of Land Use for Agriculture cont

Population growth, food
production and land use
Prof. Dr. Ir. Patrick Van Damme
(with input by L. Raes)
[email protected]
9 December 2010
History of Population Growth
and Food Production
Historical Population Growth
Source: Stein, 2008
Evolution Population Density
Source: Goldwijk, 2001
Evolution Population Density cont’
Source: Goldwijk, 2001
Evolution Population Density cont’
Source: Goldwijk, 2001
Evolution Population Density cont’
Source: Goldwijk, 2001
Evolution of Land Use for Agriculture
Source: Rankin, 2009
Evolution of Land Use for Agriculture cont’
Source: Rankin, 2009
Evolution of Land Use for Agriculture cont’
Source: Rankin, 2009
Evolution of Land Use for Agriculture cont’
Source: Rankin, 2009
Evolution of Land Use for Agriculture cont’
Source: Rankin, 2009
Evolution of Land Use for Agriculture cont’
Source: Rankin, 2009
Evolution of Land Use for Agriculture cont’
Source: Rankin, 2009
Recent History of per Capita Food
Consumption (kcal/person/day)
Source: FAO, 2002
Recent Evolution of Meat Consumption
Source: FAO, 2006
Global Biofuel Production (2000-2007)
Source: IEA, 2008
• Population growth contributed only marginally to increasing
demand for cereals, including wheat, rice and corn
→ growing consumption of meat and dairy products in
developing world (higher incomes and urbanization)
→ more grain is being fed to livestock
• Crop use for biofuel production growing even faster
• Almost all increase in global maize production between 2004
and 2007 went to make corn-based ethanol in US
→ amount of corn required to fill one gas tank with ethanol fuel
could feed one person for an entire year (Davis, 2008)
World fish capture and aquaculture
production
Source: FAO, 2003
But, Undernutrition Still is a Major
Problem
Source: FAO, 2009
Undernutrition per Region (millions)
FAO, 2009
So does the world produce enough food to feed everyone?
• YES
• World agriculture produces 17 percent more calories
per person today than 30 years ago, despite 70
percent population increase
→ enough food to provide everyone with at least 2,720
kilocalories (kcal) per person per day (FAO 2002)
→but, many people in the world do not have sufficient
land to grow, or income to purchase, enough food
(self-sufficiency ?)
• BUT:
• result of agricultural modernization, changes in diets and
population density
→ humankind increasingly depends on reduced amount of
agricultural biological diversity for its food supplies
→ a dozen species of animals provide 90 percent of animal
protein consumed globally
→ just four crop species provide half of plant-based calories in
the human diet
(FAO, 2009)
Current Situation of Food
Production and Land Use
Extent of Cultivated Systems, 2000
Cultivated systems cover 24% of the global terrestrial
surface
• Much of natural resource base in use worldwide shows worrying signs of
degradation
• According to the Millennium Ecosystem Assessment, 15 out of 24
ecosystem services examined are already being degraded or used
unsustainably
 e.g. capture fisheries and water supply
 Intensification of some ecosystem services, such ‘food production’, cause
the degradation of others
 Soil nutrient depletion
 Erosion
 Desertification,
 Depletion of freshwater reserves
 Loss of tropical forest and biodiversity
Locations Undergoing High Rates of Land Cover
Change in the Past Few Decades
Dead zones in the world, due to leakage of fertilisers
rich in nitrates and phosphates + sewage discharges
Source: Diaz and Rosenberg, 2007
Status of Terrestrial Ecoregions
Source: WWF, 2006
Mean Species Abundance
Source: UNEP, 2009
75% of the major marine fish stocks are either depleted,
overexploited or being fished at their biological limit
Source: FAO, 2002
Future Population Growth and
Food Production
Source: http://esa.un.org/UNPP/
Source: http://esa.un.org/UNPP/
Population dynamics by development groups, 1950-2050
Source: Population Division of the Department of Economic and Social UN, 2005
Future Trend per Capita Food
Consumption (kcal/person/day)
Source: FAO, 2002
Global Progress in food consumption
Source: FAO, 2002
Future Consumption of Animal Protein
(kg/person/region)
World ethanol and biodiesel projections, 2005-2018
Source: FAO-OECD, 2009
Recent Increases in Food Prices
Source: FAO
The “why” of high food prices
Longer term factors of price increase:
• continued population growth in developing countries
• changing consumer tastes
• the increasing demand for food and feed crops to use in biofuel
production
• the lack of investment in developing country (small-scale !) agriculture
in recent decades
• rising energy and associated fertiliser prices, which have significantly
increased cost of agricultural production, food processing and food
distribution
Conflict over Resources
Need for more land, water, energy and other
inputs to produce more for more people
Diminishing Land
per Person
Source: UNEP, 2009
Source: Erb et al., 2007
What land will
we use to
produce more
food?
Agricultural Suitability
Source: Ramankutty et al., 2001
Arable Land
Source: Bruinsma, 2009
Potential for Cropland Expansion?
Source: Bruinsma, 2009
• The world has considerable land reserves which could in
theory be converted to arable land
• However, extent to which this can be realized is limited
1. some of lands currently not cultivated have important
ecological functions which would be lost
2. land mostly located in just a few countries in Latin America
and sub-Saharan Africa, where lack of access and
infrastructure could limit their use
 FAO projects that by 2050 the area of arable land will be
expanded by 70 million hectares, or about 5 percent (FAO,
2009)
Sources of growth for major cereals in
developing countries (%)
Source: FAO, 2009
Climate change threatens to exacerbate
food insecurity
IPCC predicts that
• rising temperatures will decrease yields in 40
developing countries, and
• three degrees of warming (°C) will increase the price
of food by 40%
Change in Agricultural Output Potential in
2080 Due to Climate Change
Source: Cline, 2007
Projected percentage gain and losses in rainfed
cereal production potential by 2080
Source: UNEP, 2006
Possible Solutions?
Some Myths
•
•
Myth: Too Many People
Reality
– rapid population growth results from underlying inequities that deprive people,
especially poor women, of economic opportunity and security
– reduced poverty and better education lower mortality rates, which generally leads to
declining birth rates
•
•
Myth: The environment versus more food ? Or: does the environment suffer if
and when more food is produced ?…
Reality
– efforts to feed the hungry are not causing the environmental crisis
– large corporations are mainly responsible for deforestation and profiting from
developed-country consumer demand for tropical hardwoods and exotic or out-ofseason food items
– most pesticides used in the Third World are applied to export crops, playing little role
in feeding the hungry
Obvious Solutions?
 Slow population increase in less-developed
nations through family planning and
empowerment of women
 Change destructive consumption and
production patterns in more developed
nations
Establishment of Protected Areas
Degree of protection of terrestrial ecoregions and
large marine ecosystems (per cent)
Source: UNEP/WCMC, 2006
Change Dietary Patterns
Global Obesity: BMI ≥ 30 kg/m² - Top 30
Source: IASO, 2009
Restore Degraded Lands
• recent analysis by the World Resources Institute
(WRI) suggests that there are more than one billion
degraded hectares globally (area larger than Brazil)
• Some of these lands can and should be restored to
their native forest state, creating habitat for wildlife,
reducing erosion, ensuring clean water supplies, and
combating climate change by absorbing carbon
dioxide
• Others could be utilized for agriculture and thus
relieve pressure on the world’s remaining virgin
forests while creating local livelihoods
•
(McLeish & Hanson, 2010)
Use of degraded lands
Source: McLeish & Hanson, 2010
Support Small Farmers
– small farmers typically achieve at least four to five
times greater output per ha than large-scale
farmers, in part because they work their land
more intensively and use integrated, and often
more sustainable, production systems
– secure land tenure is needed, to give farmers
incentives to invest in land improvements, to
rotate crops, or to leave land fallow for the sake of
long-term soil fertility
1. Technological advances in molecular biology, energy, and information and
communications have the potential to help achieve food security and
make natural resource management more sustainable, but policymakers
and researchers must target their efforts to reach poor people.
2. Environmental degradation contributes to poverty, but also often results
from it. Food security solutions must effectively address natural resource
issues to be sustainable
3. Current policies must continue to focus on the countryside, where the
majority of poor and food-insecure people still live, but future policy
actions must pay increasing attention to growing poverty, food insecurity,
and malnutrition in urban areas
4. Agricultural policies must focus on finding ways to keep agriculture
productive as climate change continues.
Policy measures
1.
2.
3.
4.
5.
6.
publicly funded research and development to achieve sustainable yield
increases on existing land
farmers must be able to choose agricultural practices and technologies
from the full range of approaches available — agro-ecological methods,
conventional research methods, and molecular biology research
methods.
improved water use efficiency is needed.
policies should encourage farmers to make appropriate use of organic
and inorganic fertilizers and improved soil management
secure farmers' rights to land and other resources.
farmers should adopt practices to alleviate global warming, such as
reducing the burning of crop residues, and planting trees and avoiding
deforestation
Thank you…