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Sustainability, in the human impact on the environment, or the integrated effect of economic, environmental and social systems on human well-being can be measured from a household to a national economy, from a wetland to a city or an occupation. The sustainability of human-related systems involves measuring the way in which such systems interact with their surrounding environment.
The work of environmental science describes the environment, interprets the impact of human actions (anthropogenic effects) on terrestrial and aquatic ecosystems, and develops strategies for restoring ecosystems. In addition, environmental scientists help planners develop and construct buildings, transportation corridors, and utilities that protect water resources and reflect efficient and beneficial land use.[1]. Due to the interdisciplinary nature of environmental science, teams of professionals commonly work together to conduct environmental research or to produce Environmental Impact Statements.[2] Other professional organizations engender work in environmental science and aid in communication among the diverse sciences. This creates a context of thinking as to ecological footprint, and also an overall broad picture of society in regard to resources.[3]
Main article: Sustainable development
The ecological footprint is an aggregate measure of the scale of human demands on the natural environment. To provide the resources, and absorb the wastes, of the average global citizen in 2005 required 2.7 global hectares of biologically productive land and sea - this is 30% higher than the 2.1 global hectares of productive land and sea which represent the total capacity of planet Earth to produce resources and absorb wastes (leaving no ecological capacity to support non-human ecosystems).[4] The resulting ecological deficit must be met from unsustainable sources - use of stored resources including fossil fuels, and "mining" natural resources including forests and fisheries at greater than their rate of regeneration.
The aim of Sustainable Development is to reduce environmental impact while improving quality of life for those currently disadvantaged. By this definition, only Cuba has achieved sustainable development during the period from 1978 to 2003, and this was due in part to an oil embargo imposed upon them[5]. Elsewhere, the trend over time has in almost all cases been increasing human development, at the cost of increasing ecological footprint.
Comparing the per capita demands of humans on the environment can obscure the important role of population growth. Overall pressure on the environment is a function of population as well as of levels of consumption and the efficiency of resource use.[6]
At a fundamental level human impact on the Earth is being manifest through changes in the global biogeochemical cycles of chemicals that are critical to life, most notably those of water, oxygen, carbon, nitrogen and phosphorus.
A wealth of information generated by national, regional and city-scale State of the Environment reports generally confirms the global picture that human societies are becoming less sustainable over time.[7]
An "unsustainable situation" occurs when natural capital (the sum total of nature's resources) is used up faster than it can be replenished. Sustainability requires that human activity only uses nature's resources at a rate at which they can be replenished naturally. Inherently the concept of sustainable development is intertwined with the concept of carrying capacity. Theoretically, the long-term result of environmental degradation is the inability to sustain human life. Such degradation on a global scale could imply extinction for humanity.
See also: Ecological footprint |
Natural systems (often referred to as ecosystem services) are humanity's life-support system, providing the necessary conditions for humans to flourish. Over the last 50 years the rapidly escalating and potentially critical nature of human global impact on the biodiversity of these ecosystem services has become the source of major biological concern.[8][9]
At a fundamental level, human impact on the Earth is being manifest through changes in the global biogeochemical cycles of chemicals that are critical to life. Most notably the Water cycle, Oxygen cycle, Carbon cycle, Nitrogen cycle and the Phosphorus cycle. There is growing evidence that human activity is having a significant effect on all of these cycles.[10]
There are two major ways of reducing human impact on the planet. The first is to monitor and respond to direct human impacts on the oceans and freshwater systems, the land and atmosphere (see direct impacts below). This approach is based on information gained from environmental science and conservation biology.[8] However, this is management at the end of a long series of causal factors (known to ecologists as drivers) that are initiated by human consumption, our demand for food, energy, materials and water [11] (see indirect impacts below).
See also: Climate and Climate change |
The most obvious human impact on the atmosphere is the air pollution in our cities. The pollutants include toxic chemicals such as nitrogen oxides, sulphur oxides, volatile organic compounds and particulate matter that produce photochemical smog and acid rain. Anthropogenic particulates such as sulphate aerosols in the atmosphere reduce the direct irradiance of the Earth's surface. Known as global dimming the decrease is estimated at about 4% between 1960 and 1990 although the trend has subsequently reversed. Global dimming may have disturbed the global water cycle by reducing evaporation and rainfall in some areas. It also creates a cooling effect and this may have partially masked the effect of greenhouse gases on global warming.[12] [13] However, it is now human-induced climate change and the carbon cycle that have become a major focus of scientific research because of the potential for catastrophic effects on both biodiversity and human communities (see Energy below).
See also: Overfishing and Marine pollution |
Oceans and their circulation patterns have a critical effect on climate and the food supply for both humans and other organisms. Major environmental impacts occur in the more habitable regions of the oceans – the estuaries, coastline and bays. Because of their vastness oceans act as a dumping ground for human waste. Trends of concern include: ocean warming, reef bleaching and sea level rise, all due to climate change together with the possibility for a sudden alteration of present-day ocean currents which could drastically alter the climate in some regions of the globe; over-fishing (beyond sustainable levels); and ocean acidification due to dissolved carbon dioxide.
Remedial strategies include: more careful waste management, statutory control of overfishing, reduction of fossil fuel emissions, and restoration of coastal and other marine habitat.
See also: Freshwater, Desalination, Water resources, and Water crisis |
Freshwater habitat is the world’s most vulnerable of the major biological systems due to the human need for potable water for food irrigation, industry and domestic use. Human freshwater withdrawals make up about 10% of global freshwater runoff, and of this 15-35% is considered unsustainable - a proportion that is likely to increase as climate changeworsens, populations increase, and water supplies become polluted and unsanitary.
In the industrial world demand management has slowed absolute usage rates but in the developing world water security, and therefore food security, remain among the most important issues to address. Increasing urbanization pollutes clean water supplies and much of the world still does not have access to clean, safe water.
See also: Land use, land-use change and forestry and Urbanization |
Land use change is fundamental to the operations of the biosphere. This includes alteration to biogeochemical cycles, effects of agriculture, proportions of forest and woodland, grassland and pasture.
See also: Forestry, Deforestation, and Carbon sequestration |
Historically about 47% of the world’s forests have been lost to human use. Present-day forests occupy about a quarter of the world’s ice-free land with about half occurring in the tropics[14] In temperate and boreal regions forest area is gradually increasing (with the exception of Siberia), but deforestation in the tropics is of major concern.
Forests can moderate the local climate and the global water cycle through their light reflectance (albedo) and evapotranspiration. They also conserve biodiversity, protect water quality, preserve soil and soil quality, provide fuel and pharmaceuticals, and purify the air. These free ecosystem services have no market value and so forest conservation has little appeal when compared with the economic benefits of logging and clearance which, through soil degradation and organic decomposition returns carbon dioxide to the atmosphere.
The United Nations Food and Agriculture Organisation (FAO) has estimated that about 90% of the carbon stored in land vegetation is locked up in trees and that they sequester about 50% more carbon than is present in the atmosphere. Changes in land use currently contribute about 20% of total global carbon emissions (in heavily logged Indonesia and Brazil it is the greatest source of emissions).[15] Climate change can be mitigated by sequestering carbon in reafforestation schemes, new plantations, and timber products. Wood biomass is a renewable carbon-neutral fuel.
The FAO has concluded that, over the period 2005–2050, effective use of tree planting could absorb about 10–20% of man-made emissions – so clearly we need to monitor the condition of the world's forests very closely (both reafforestation and deforestation) as they must be part of any coordinated emissions mitigation strategy.[16]
See also: Agriculture and Green Revolution |
Feeding more than six billion human bodies takes a heavy toll on the Earth’s resources. This begins with the human appropriation of about 38% [17] of the Earth’s land surface and about 20% of its net primary productivity[18]. Added to this are the resource-hungry activities of industrial agribusiness – everything from the initial cultivation need for irrigation water, synthetic fertilizers and pesticides to the resource costs of food packaging, transport (now a major part of global trade) and retail. The benefits of food production are obvious: without food we cannot survive. But the list of costs is a long one: topsoil depletion, erosion and conversion to desert from tillage for monocultures of annual crops; overgrazing; salinization; sodification; waterlogging; high levels of fossil fuel use; reliance on inorganic fertilisers and synthetic organic pesticides; reductions in genetic diversity by the mass use of monocultures; water resource depletion; pollution of waterbodies by run-off and groundwater contamination; social problems including the decline of family farms and weakening of rural communities.[19]
See also: Extinction and International Union for Conservation of Nature |
In line with human migration and population growth, species extinctions have progressively increased to a rate unprecedented since the Cretaceous–Tertiary extinction event. Known as the Holocene extinction event this human-induced extinction of species ranks as one of the worlds six mass extinction events. Some scientific estimates indicate that up to half of presently existing species may become extinct by 2100.[20][21]
Loss of biodiversity can be attributed largely to the appropriation of land for agroforestry. Current extinction rate are 100 to 1000 times their prehuman levels with more than 10% birds and mammals threatened, about 8% of plants and 5% of fish and more than 20% of freshwater species.
See also: Introduced species and Invasive species |
Increasingly efficient global transport has facilitated the spread of organisms across the planet. The most stark examples are human diseases like HIV AIDS, mad cow disease and bird flu but invasive plants and animals are now, after climate change and land clearing, the greatest threat to native biodiversity.[22] Non-indigenous organisms often quickly occupy disturbed land but can also devastate natural areas where, in the absence of their natural predators, they are able to thrive.
Addressing sustainability now focuses much of its attention on managing levels of consumption and resource impact by seeking, for example, to modify individual lifestyles, and to apply ideas like ethical consumerism, dematerialisation and decarbonisation, while at the same time exploring more environmentally friendly technology and methods through ecodesign and industrial ecology.
At present individual and household use of resources like energy and water is monitored through domestic water and energy bills and car fuel use – but much greater quantities of these resources are embodied in the goods and services we use. In the same way society as a whole tends to consider environmental management in terms of direct impacts rather than their driver - human consumption. Patterns of consumption must reflect the cleverer use of resources: e.g. using renewable energy rather than fossil fuels and fewer embodied resources in goods and services.[23][24]
See also: Consumption, Primary production, Simple living, Consumerism, Ethical consumerism, Biotechnology, and Appropriate technology |
There is debate about the relationship between natural and human capital - whether we must live off the interest of our natural capital (strong sustainability).[25]) or if it is possible to thrive indefinitely while taking more natural resources, provided total capital remains constant (weak sustainability).[26] Consumerism focuses on the end-product. It tends to stay away from the focus on the production and transportation stage of the goods.
In coming to terms with human consumption sustainability science focuses on four interconected and basic human resource needs - for: water (agriculture, industry, domestic use), energy (industry, transport, tools and appliances), materials (manufacturing, construction) and food (horticulture, agriculture and agribusiness)[11]. Each of these resources are discussed below.
See also: Energy and Renewable energy |
Since the industrial revolution the concentrated energy of the Sun stored in fossilised plants as fossil fuels have been a major driver of technology and the source of both economic and political power.
In 2007, after prolonged skepticism about the human contribution to climate change, climate scientists of the IPCC concluded that there was at least a 90% probability that this atmospheric increase in CO2 was human-induced - essentially due to fossil fuel emissions and, to a lesser extent, the CO2 released from changes in land use.
Projections for the coming century indicate that a minimum of 500 ppm can be expected and possibly as much as 1000 ppm. Stabilising the world’s climate will require high income countries to reduce their emissions by 60-90% over 2006 levels by 2050. This should stabilise atmospheric carbon dioxide levels at 450-650 ppm from current levels of about 380 ppm. Above this level and temperatures would probably rise by more than 2 °C (36 °F) to produce “catastrophic” climate change.[27][28] Reduction of current CO2 levels must be achieved against a background of global population increase and developing countries aspiring to energy-intensive high consumption Western lifestyles.[29]
Projecting climate into the future and forecasting regional impacts depends on our understanding of the exchange of carbon dioxide between the atmosphere, oceans and land ecosystems. NOAA (National Oceanic & Atmospheric Administration), is charged to provide the atmospheric measurements and analyses required to track the fate of carbon dioxide emissions caused by the burning of fossil fuels and biomass, and to reduce uncertainties in how the exchange of carbon responds to the variations and trends of climate and land use.[30]
See also: Water, Water cycle, and Water resources |
Water covers 71% of the Earth's surface. The oceans contain 97.2% of the Earth's water. The Antarctic ice sheet contains 90% of all fresh water on Earth. Condensed atmospheric water, as clouds, contributes to the Earth's albedo.
Awareness of the global importance of preserving water for ecosystem services has only just begun as, during the 20th century, more than half the world’s wetlands have been lost along with their valuable environmental services. Biodiversity-rich freshwater ecosystems are currently declining faster than marine or land ecosystems.[31]
In the decade 1951-60 human water withdrawals were four times greater than the previous decade. This rapid increase resulted from scientific and technological developments impacting through the economy - especially the increase in irrigated land, growth in industrial and power sectors, and intensive dam construction on all continents. This altered the water cycle of rivers and lakes, affected their water quality and therefore potential as a human resource, and altered the global water cycle.[32] Currently towards 35% of human water use is unsustainable, drawing on diminishing aquifers and reducing flows of major rivers.
Over the period 1961 to 2001 there was a doubling of demand and over the same period agricultural use increased by 75%, industrial use by more than 200%, and domestic use more than 400%. Humans currently use 40-50% of the globally available freshwater in the approximate proportion of 70% for agriculture, 22% for industry, and 8% for domestic purposes and the total amount is progressively increasing being about five times that at the beginning of the 20th century.[32]
The path forward appears to lie in improving water use efficiency through: demand management; maximising water resource productivity of agriculture; minimising the water intensity (embodied water) of goods and services; addressing shortages in the non-industrialised world; moving production from areas of low productivity to those with high productivity; and planning for climate change.[31]
See also: Ecolabelling, Ecodesign, Recycling, Extended producer responsibility, and Biomaterial |
Materials used by humans are still increasing in volume, number, diversity and toxicity. Synthetic chemical production is escalating and global transport systems accelerate distribution across the globe.[33] Much of the sustainability effort is directed at converting the linear path of materials from one of extraction to production and disposal as waste, to a cyclical one that reuses materials indefinitely, much like the waste cycle in nature.
See also: Recycling, Dematerialization, Zero waste, and Industrial ecology |
As more materials are transported round the world material flow analysis is becoming widely accepted as an important part of sustainability accounting at the national level. The linear path of products (extraction, manufacture, disposal in rubbish tip) is being converted to a more circular material flow (like that in nature) as the world comes to grips with dematerialization, decarbonisation and zero waste.[33] Industry, business and government are adopting the ideas of industrial metabolism, industrial ecology, ecodesign [34], ecolabelling, product stewardship, and extended producer responsibility. In addition to the well-established “reduce, reuse and recycle” shoppers are using their purchasing power for ethical consumerism.[35]
See also: Sustainable agriculture, Food security, Food miles, Environmental vegetarianism, and Nutritional Economics |
The American Public Health Association (APHA) defines a "sustainable food system"[36][37] as "one that provides healthy food to meet current food needs while maintaining healthy ecosystems that can also provide food for generations to come with minimal negative impact to the environment. A sustainable food system also encourages local production and distribution infrastructures and makes nutritious food available, accessible, and affordable to all. Further, it is humane and just, protecting farmers and other workers, consumers, and communities."[38]
Concerns about the environmental impacts of agribusiness and the stark contrast between the obesity problems of the Western world and the poverty and food insecurity of the developing world have generated a strong movement towards healthy, sustainable eating as a major component of overall ethical consumerism.[39]
The environmental effects of different dietary patterns depend on various factors, including the proportion of animal and plant foods consumed and the method of food production.[40][41][42][43] The World Health Organisation has published a Global Strategy on Diet, Physical Activity and Health which was endorsed by the May 2004 World Health Assembly. It recommends the Mediterranean diet which is associated with health and longevity and is low in meat, rich in fruits and vegetables, low in added sugar and limited salt, and low in saturated fatty acids; the traditional source of fat in the Mediterranean is olive oil, rich in monounsaturated fat. The healthy rice-based Japanese diet is also high in carbohydrates and low in fat. Both diets are low in meat and saturated fats and high in legumes and other vegetables; they are associated with a low incidence of ailments and low environmental impact.
At the local level there are various movements working towards more sustainable use of wastelands, peripheral urban land and domestic gardens. This includes permaculture[44], urban horticulture, local food, slow food, and organic gardening.
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This section is look fairly good, we just need to keep it tight and summarise, give the reader a quick glance at how we can measure sustainability and point them in the right direction for more information. Nick carson (talk) 12:16, 8 December 2008 (UTC)
It looks like this is going to be the major area of the article. There is some new stuff here and a lot of the old stuff which I have brought over and attempted to integrate... but not all of the old stuff from the other area in the current article. We can pick through it now and chop out dead wood. There is a lot of important info here, so now it is time to scrutinize it... and hopefully not add a lot, except more good citation/notes and break down the current information to as small an amount from where it is as possible while retaining as much of this good information from the present article also.
I would encourage all to make an effort to locate good ref/notes now to add to this area that can be clicked on to navigate to other information, that may be a good way to break the size of the article section down... by referring to something with a ref. citation instead of spelling it out to a large degree. Old ref/notes can be updated/replaced to better information presentation of connected information of sources.
In effect this area of the article above^ could replace the areas in the article presently, replacing including, the section Sustainability and development... downwards and stopping at Sustainability and economics section, which is an altogether different area. skip sievert (talk) 23:52, 7 January 2009 (UTC)
- include concepts such as Ecological Footprint and other methods of measuring sustainability
Sustainability (either as total human impact on the environment, or the integrated effect of economic, environmental and social systems on human well-being) can be measured at any level of biological or human organisation, from a garden to the biosphere, from a household to a national economy, from a wetland to a city. an occupation. Measuring the sustainability of human-related systems involves measuring the way in which such systems interact with their surrounding environment. This is usually expressed as:
The ecological footprint is an aggregate measure of the scale of human demands on the natural environment. To provide the resources, and absorb the wastes, of the average global citizen in 2005 required 2.7 global hectares of biologically productive land and sea - this is 30% higher than the 2.1 global hectares of productive land and sea which represent the total capacity of planet Earth to produce resources and absorb wastes (leaving no ecological capacity to support non-human ecosystems).[1] The resulting ecological deficit must be met from unsustainable sources - use of stored resources including fossil fuels, and "mining" natural resources including forests and fisheries at greater than their rate of regeneration.
Yet most of the world's population has an ecological footprint equal to or less than 2.1 global hectares, and nations in this category span a wide range in terms of quality of life.
The aim of Sustainable Develoment is to reduce environmental impact while improving quality of life for those currently disadvantaged. By this definition, only Cuba has achieved sustainable development during the period from 1978 to 2003, and this was due in part to an oil embargo imposed upon them[2]. Elsewhere, the trend over time has in almost all cases been increasing human development, at the cost of increasing ecological footprint.
Comparing the per capita demands of humans on the environment can obscure the important role of population growth. Overall pressure on the environment is a function of population as well as of levels of consumption and the efficiency of resource use.[3]
The Millennium Ecosystem Assessment provides the most comprehensive current synthesis of the state of the Earth’s ecosystems. The report refers to natural systems as humanity's life-support system, providing the necessary services for humans to flourish.
At a fundamental level human impact on the Earth is being manifest through changes in the global biogeochemical cycles of chemicals that are critical to life, most notably those of water, oxygen, carbon, nitrogen and phosphorus.
Human activity is also having a rapidly escalating and potentially critical impact on the biodiversity of ecosystems, reducing their resilience and their capacity to support humans and life in general.[4] [5]
A wealth of information generated by national, regional and city-scale State of the Environment reports generally confirms the global picture that human societies are becoming less sustainable over time.[6]
Sustainability measurement |
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To date, measures of pressure on the environment show increasing resource use per capita and in total[7], and measures of the state of the environment show accelerating environmental degradation. It follows that current actions to improve sustainability are not yet sufficiently effective, and not applied on a sufficient scale. Nonetheless there are many small-scale examples of positive action towards sustainability. Information on the effectiveness of responses can be valuable, long before positive impacts on the environment as a whole, or reductions in per capita resource use, become apparent.
Monitoring the direct human impacts on the state of the environment and of oceans and freshwater systems, the land and atmosphere represents management at the end of a long series of causal factors (known to ecologists as drivers) that are initiated by human consumption, our demand for food, energy, materials and water [8] (see indirect impacts below).
Many organisations and individuals, and some cities and countries, are achieving measurable progress towards managing
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