130 likes | 246 Views
AG704 Agriculture, Environment and Sustainability Convenor: Dr. John A Finn Dr. Julian Park. Objectives . Introduce the module Introduce website Provide a historical perspective that outlines why sustainability has become an issue Discuss Sustainability as a concept.
E N D
AG704 Agriculture, Environment and SustainabilityConvenor: Dr. John A Finn Dr. Julian Park
Objectives • 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: • 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: • Population growth • Food production to match population growth • Resource consumption • per capita and total rates of consumption, renewal • Limits on science and technology • Limits on the environment
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.
Perspectives from history • 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 • 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, • 1950 Green Revolution (2.5 billion) • plant breeding and genetics, fertilisers, pesticides • 2000 ?????????????? (6 billion) • 2050 (8-10 billion)
Agriculture and environmental change • 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 • 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 long-term 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 • Sustainable development meets the needs of the present generation without compromising the ability of future generations to meet their own needs. (Brundtland 1987) • ‘Needs’ and ‘Limitations’ • 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.