Transcript Document 7771435

AG704 Agriculture, Environment
and Sustainability
Convenor:
Dr. John A Finn
Dr. Julian Park
Objectives
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Introduce the module
Introduce website
Provide a historical perspective that outlines
why sustainability has become an issue
Discuss Sustainability as a concept
AG704 Agriculture, Environment and Sustainability
 What
issues/questions do you
expect to encounter in this module?
Specific examples of issues:
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Soil erosion and land degradation
Genetically modified crops
Pollution
Climate change and consequences
Irrigation
Agrochemical usage
Profitability of farming
Precautionary principle
Renewable energy, polluter-pays principle
Rate of consumption of non-renewables
Examples of the BIG issues:
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Population growth
Food production to match population
growth
Resource consumption
• per capita and total rates of consumption,
renewal
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Limits on science and technology
Limits on the environment
In a nutshell:
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The current human presence and scale of
activity on Earth is truly unique:
never before in Earth's history have there
existed so many people, each using so
many resources and involving such a
degree of manipulation of Earth's
ecosystems.
Perspectives from history
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Development of human population size
Development of agriculture as an
(extremely effective ) agent of
environmental change
What are the consequences of these
developments?
A (very) brief history of Agriculture
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Until about 12000 years ago- hunter-gatherer 2-20m
 Domestication of crops
 Human settlement, civilisation
 1800 Global agricultural evolution (1 billion)
• nutritious and productive foods from foreign countries
(maize, potato etc), modern rotations, science applied to
agriculture,
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1950 Green Revolution (2.5 billion)
• plant breeding and genetics, fertilisers, pesticides
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2000 ?????????????? (6 billion)
 2050
(8-10 billion)
Agriculture and environmental change
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Agricultural ecosystems have caused four
species (barley, maize, rice and wheat) to
occupy about 40% of global cropland as
monocultures
simplification and homogenisation of
world’s ecosystems
What will be the impacts of a further
doubling in food production?
(Tilman, 1999 )
Consequences of these developments
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Unprecedented rate and scale of resource
consumption e.g. energy (O/H)
Conversion of natural ecosystems
Environmental degradation at local and
global scales
Short-term gains with ignorance of longterm consequences
Food production to match population?
See <www.pnas.org> volume 96
In a nutshell:

The current human presence and scale of
activity on Earth is truly unique:
never before in Earth's history have there
existed so many people, each using so
many resources and involving such a
degree of manipulation of Earth's
ecosystems.
Sustainability- Brundtland definition
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Sustainable development meets the needs of
the present generation without
compromising the ability of future
generations to meet their own needs.
(Brundtland 1987)
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‘Needs’ and ‘Limitations’
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For an introductory discussion of the concept/definition of
sustainability: Spedding, C.R.W., 1996, Agriculture and the
citizen.
Fig. 1. Based on FAO data, world food production,
measured as the sum of cereals, coarse grains and root
crops, almost doubled from 1961 to 1996. A linear
regression, and 95% and 99% confidence intervals for the
regression, are shown.