iscn 2016: session 1: food sustainability at the micro and macro level
TRANSCRIPT
Food Security and Climate Change
Sophie Laurie Natural Environment Research Council Tim Benton RCUK Global Food Security Champion
All the four Dimensions of Food Security are Affected by Climate Change
Tim Wheeler and Joachim von Braun Climate change impacts on global food security. Science 134, 508 (2013) doi 10.1126/science.1239402
1. Food availability: the availability of sufficient quantities of food of
appropriate quality, supplied through domestic production or imports. 2. Food access: access by individuals to adequate resources
(entitlements) for acquiring appropriate foods for a nutritious diet. 3. Food utilization: Utilization of food through adequate diet, clean
water, sanitation and health care to reach a state of nutritional well-being where all physiological needs are met.
4. Stability of the food system: To be food secure, a population, household or individual must have access to adequate food at all times.
Global Food Security Programme
• We foster a systems’ view across all major public funders of research
“Food security, nutrition and sustainable agriculture must remain a priority on the political agenda, to be addressed through a cross-cutting and inclusive approach, relevant to all stakeholders at global, regional and national level.” [G8 statement July 2009]
Stakeholders in: Academia Industries Civil Society The Public
FOOD SECURITY; THE PROBLEM AT GLOBAL SCALE
More people on the planet
5
N.Am 352 mln
S.Am 563 mln
Asia 4299 mln
Europe 733 mln
Africa 1033 mln
+34%
+21%
+29% +132%
-2%
2050
2013 data: www.prb.org
+30%
Oceania (38mln)
MOOC: Growing our Future Food: Crops
Income creates demand
Tilman et al., 2011 (PNAS)
2000: 60% middle class “western” vs 20% “eastern” 2050: 12% vs 68%
income
Phos
phor
us d
eman
d
Supply chain logistics: risks and resilience
THE WORLD IS CHANGING
2010200019901980197019601950194019301920
35
34
33
32
31
30
29
28
27
26
jul
Midwest: July max temp
Increasing extremes likely to make yields increasingly variable (as well as reducing average yields) Challinor NCC 2014
Increasing extremes likely to make yields increasingly variable (as well as reducing average yields) Challinor NCC 2014
1983-86 2009-12
PNAS, online Aug 2012
From Wheeler & Von Braun (2013) after World Bank (2010)
Foley et al 2011
THE CHALLENGES OF SUSTAINABLE AGRICULTURE
1. Paradoxically sustainability requires intensification
Outputs have to rise per unit area to keep pace with per capita demand
15 gallons
Outputs have to rise per unit area to keep pace with per capita demand
15 gallons
Need to improve yields via breeding
Fig 1. Time series data on wheat yields per ha for an area in Scotland, dating back to 1700. The data are the red points, with a “smoother” (a spline curve, with smoothness fitted using cross-validation) shown in black, with the standard error of the fit being shown by dotted lines). (a) shows the whole time series, (b) shows from 1940 onwards, with the smoother projected forwards to 2050. Since about 1985, the rate of annual increase in yield has declined.
Natural land is under pressure
Grassini et al., 2013
Innovation space
• Manage soils better • Efficiency of resource use,
using new and best knowledge – Best practice (perhaps especially)
in low input systems – More research needed in
different farming systems (e.g. extensive & vertical)
– “Precision” Farming – Pest control – Fertilisers and their efficiency – ICT/forecasting/sensing etc
• New genetics (crops and livestock)
Robotic weeding: Weed recognition through machine vision (26 species); applies Glyphosphate only to the leaf of the weed (~1 g per hectare cf 720 g/ha) Simon Blackmore, Harper Adams
Stockbridge Technology Centre’s LED Blockhouse
www.yieldgap.org
But intensification not needed equally everywhere.
THE CHALLENGES OF SUSTAINABLE AGRICULTURE
2. Understanding sustainability
£29.52
£95.87
£40.18 £70.20
£2.63
£95.22
Environmental Cost:GHGs from Production
Environmental Cost:GHGs from Application
Health cost: Air Quality
Provisioning Cost:Water Quality
Recreation Cost:Fishing
Biodiversity Cost:Wetlands/Aquatic
Total Environmental Cost ~ £333.61 For comparison p ha costs for wheat are ~£700 and gross income ~£1400 = £900 (less rent etc)
Environmental cost estimates per hectare based on application of fertiliser at 190 kg N per hectare
Water use efficiency
Nitrogen use efficiency
Phosphorus use efficiency
Yield quantity
Yield quality
Soil N content
Soil P content
Soil carbon
Soil K content
Soil compactness
Soil erosion
Soil biodiversity
Total weeds
Annual weeds
Perennial weeds Pest
abundanceNatural enemy
abundance
Water flow control
CO2emissions
CH4emissions
N2O emissions
Animal welfare
Worker welfare
ProfitCosts
Plant richness
Invertebrate richness
Vertebrate richness
Plant abundance
Invertebrate abundance
Vertebrate abundance
Soil moisture
Pollination
Energy use efficiencyWater N
load
Water P load
Water pesticide load
Plants
Invertebrates
Vertebrates
Pollination
Soil carbon
Water flow
Nutrient use efficiency
Water use efficiency
Energy use efficiency
GHG emissions
Welfare
Biodiversity
Yield
Water use efficiency
Pollination
Welfare
Nutrient use efficiency
Energy use efficiency
GHG emissions
Yield
ProfitCosts
Water quality
WeedsAnimal pests
Soil nutrients
Soil biodiversity
Soil physical structure
Pest regulation
Soil fertility
Hydrology
Profit
Costs
Aspects of Sustainability
Quantitative review of studies assessing “sustainable agriculture” (German, Thompson & Benton, in prep)
There is no recipe for “sustainable agriculture”
High yielding organic agriculture can impact on ecology in similar ways to conventional farming
Gabriel et al 2013 J appl ecology
THE CHALLENGES OF SUSTAINABLE AGRICULTURE
3. The spatial scale is important
What does land do?
Given the competition for land: need to ensure land used more efficiently: whether it is producing water, biodiversity or food
Smarter landscapes are possible
• It is possible to “design” landscapes better to deliver a range of goods
• Governance issues abound
THE CHALLENGES OF SUSTAINABLE AGRICULTURE
4. Changing demand to make space for sustainability
IT’S NOT JUST ABOUT PRODUCTION Global food losses/waste is estimated to be 1.3 billion tonnes per annum (pa), equating to approximately one third of edible food intended for human consumption The total food production of sub-Saharan Africa = EU+N Am food waste (230mt). Need to recycle “from farm to flush”
Diet, nutrition and health: • Diabetes UK cost ~£30bn • >50% of adult Chinese are pre-
diabetic • over-consumption associated
with >20% of deaths globally; • Malnutrition & micronutrients
JAMA. 2013;310(9):948-958. doi:10.1001/jama.2013.168118
The twin burdens of obesity and malnutrition
Who wins, who loses?
• Access to food, price and nutrition – Poorest’s food nutritionally
bad
• Agriculture and land use – Private gains vs public
losses? – GM and attitudes to risk
NEED FOR CHANGE
Changing our attitude to food?
• We want abundant, cheap, safe, nutritious, high-welfare and sustainable food – but we can’t have it all
If we carry on as we are…
• We need to produce more food by 2050 than we have done in human history
• This will require 120% more water; 42% more cropland and loss of 14% more forest
• This will emit enough carbon dioxide to create 2 degrees of global warming
• We’ll lose much of the world’s biodiversity
• Food will increasingly be associated with early deaths
NCC 2014
Changing diets: • Eat less • Eat more healthily
(e.g. more vegetables)
• Eat novel foods
Conclusions
• We can grow more food and reduce its environmental impact
• There is no “magic bullet” but scope for many innovations in many areas
• Unlikely we can grow enough food to meet demand as it is currently projected (without significant inequality and unsustainability)
• Social change therefore as important as scientific innovation
• Challenges require significant research investment, important to protect budgets
Economic growth is only one outcome
• Increasing food production will not create a sustainable agri-food system with food security