* This is the theoretical measurement of the amount of land and water a population requires to produce the resources it consumes and to absorb its waste, under prevailing technology. * It is measured in acres or hectares and calculates the amount of the earth’s bioproductive space – ecologically productive land and water – a given population is consuming. * The calculation takes into account the following:
* Arable land – the amount of land required for growing crops. * Pasture land – resources required for growing animals for meat, hides, milk, etc. * Forests – for fuel, furniture and buildings, and also for ecosystems services like climate stability and erosion prevention. * Oceans – for fish and other marine products.
* Infrastructure – transportation, factories and housing, based on the built-up land used for these needs. * Energy costs – land required for absorbing carbon dioxide emissions and other energy wastes. * Species extinction and toxic pollution of the air, water and land are not yet taken into account in calculating ecological footprints. Our global and national footprints
* The planet’s biological productive capacity (biocapacity) is around 1.9 hectares or 4.7 acres per person but we’re currently using 2.2 hectares per person thus living beyond the planet’s biocapacity to sustain us by 15%. * This deficit is showing up as failing natural ecosystems – forests, oceans, fisheries, coral reefs, rivers, soils and water – and global warming. * The planet’s biocapacity is affected by the global population and the rate of consumption- higher consumption depletes the planet’s carrying, renewal and regeneration capacity. * If global population trends continue, the ecological footprint available would reduce to 1.5 hectares per person by 2050 and if the world’s rate of consumption increases to the same rate as rich western countries, we would need 4 or 5 more planets to sustain ourselves.
* The footprint varies across the globe from 8 or more “global hectares” for the biggest consumers in the US, UAE, Kuwait and Denmark to 0.5 hectares in DRC, Haiti, Afghanistan, Bangladesh and Malawi. * The USA is the country with the largest per capita footprint in the world at 9.57 hectares and at this rate the planet’s biocapacity could only support 1.2 billion people while on the other hand at if everyone lived like an average person in Bangladesh, the earth could support roughly 22 billion people. * The global ecological capacity has grown from about 70% of the planet’s biocapacity in 1961 to 120% in 1999 and future projection show an increase to about 180%-220% by 2050. The Living Planet Index
* This measures trends in the earth biological diversity and based on figures from 2005, indicates that global diversity has declined by nearly a third since 1970. * The US and China account for more than two-fifths of the planet’s ecological footprint with 21% each. * According to the 2008 report, the world is heading for an “ecological credit crunch” and calculates that humans are using 30% more resources than the earth can replenish each year. * This is leading to deforestation, degraded soils, polluted air and water, and dramatic declines in the numbers of fish and other species. People are running an ecological debt of $4-$4.5 trillion. * The problem is also getting worse: populations and consumption keep growing faster than our ability to find new ways (technology) of expanding produce from the natural world. * The report also contains detailed information on every countries’ “water footprint” and claims that 50 countries are already experiencing “moderate to severe water stress on a year-round basis”. * 27 countries are ‘importing” more than half the water they consume which is used to produce goods ranging from wheat to cotton – including the UK, Switzerland, Austria, Norway and the Netherlands. Theories of population and resources
Thomas Malthus’s theory of population
* In 1978 Reverend Thomas Malthus produced his Essays on the Principle of Population Growth. He believed that there was finite optimum size in relation to food supply, and that any increase in population beyond this point would lead to a decline in the standard of living and to “war, famine and disease”. * He based his theory on two principles:
* In the absence of checks, population will grow at a geometric/exponential rate and could double every 25 years. * Food supply at best only increases at an arithmetic rate. * His principle used potential but not actual growth figures for both population and food production and as there is a limit to the amount of food that can be produced, it determines a “ceiling” to the population growth in a given country. * He also suggested preventive and positive checks as two main ways to slow population growth. Preventive checks include abstinence from marriage or a delay in the time of marriage and abstinence from sex within marriage, all of which would reduce fertility rate. Positive checks such as lack of food, disease and war directly affected death rates. * He suggested that the optimum population exists related to resources and the level of technology – which is now related to the concept of over and under population rather than optimum population. * An optimum population is difficult to identify as technology improves, resources availability and attitudes changes.
* During the industrial revolution, agriculture production grew at a rate that exceeded the rate of population growth – the industrial development affected agricultural production through intensification (labour and capital) and extensification (more land). * Since Malthus’s time people have increase food production in many ways including; draining marshlands, reclaiming land from the sea, cross-breeding cattle, use of high-yielding varieties of crops, terracing steep slopes, growing crops in greenhouses, using more sophisticated irrigation techniques such as hydroponics, growing new foods such as soya, making artificial fertilizers, farming native crop and animal species, and fish farming. * Since the 1950s there have been two main phases of agricultural production; high yielding varieties (HYVs) and extensification and since the 1980s, intensification. * These have created environmental issues such as loss of habitat, use of agrochemicals and high-energy farming. Esther Boserup’s theory of population
* An anti-Malthusian view is one of Esther Boserup (1965), she believed that people have the resources to increase food production – the greatest resource is knowledge and technology, when a need arises someone will find a solution. * Boserup suggests that in a preindustrial society an increase in population stimulated a change in agricultural techniques so that more food could be produced – population growth has thus enabled agricultural development to occur. * She examined different land-use systems and their intensity of production. This was measured by the frequency of cropping. At one extreme was with shifting cultivation; at its least intensive, any one piece of land would be used less than once every 100 years. At the other extreme was the multicropping system, with more than one harvest per year. * She suggested that there was a close connection between the agricultural techniques used and the type of land-use system. The most primitive was shifting cultivation and increased cropping frequency occurring when higher yields are needed.