Resource depletion

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Tar sands in Alberta, 2008. Oil is one of the most used resources by humans. Tar sands in alberta 2008.jpg
Tar sands in Alberta, 2008. Oil is one of the most used resources by humans.

Resource depletion is the consumption of a resource faster than it can be replenished. Natural resources are commonly divided between renewable resources and non-renewable resources (see also mineral resource classification). Use of either of these forms of resources beyond their rate of replacement is considered to be resource depletion. [1] The value of a resource is a direct result of its availability in nature and the cost of extracting the resource, the more a resource is depleted the more the value of the resource increases. [2] There are several types of resource depletion, the most known being: Aquifer depletion, deforestation, mining for fossil fuels and minerals, pollution or contamination of resources, slash-and-burn agricultural practices, Soil erosion, and overconsumption, excessive or unnecessary use of resources.

Contents

Resource depletion is most commonly used in reference to farming, fishing, mining, water usage, and consumption of fossil fuels. [2] Depletion of wildlife populations is called defaunation . [3]

Depletion accounting

In an effort to offset the depletion of resources, theorists have come up with depletion accounting. Better known as 'green accounting,' depletion accounting aims to account for nature's value on an equal footing with the market economy. [4] Resource depletion accounting uses data provided from countries to estimate the adjustments needed due to their use and depletion of the natural capital available to them. [5] Natural capital are natural resources such as mineral deposits or timber stocks. Depletion accounting factors in several different influences such as the number of years until resource exhaustion, the cost of resource extraction and the demand of the resource. [5] Resource extraction industries make up a large part of the economic activity in developing countries. This, in turn, leads to higher levels of resource depletion and environmental degradation in developing countries. [5] Theorists argue that implementation of resource depletion accounting is necessary in developing countries. Depletion accounting also seeks to measure the social value of natural resources and ecosystems. [6] Measurement of social value is sought through ecosystem services, which are defined as the benefits of nature to households, communities and economies. [6]

Importance

There are many different groups interested in depletion accounting. Environmentalists are interested in depletion accounting as a way to track the use of natural resources over time, hold governments accountable or to compare their environmental conditions to those of another country. [4] Economists want to measure resource depletion to understand how financially reliant countries or corporations are on non-renewable resources, whether this use can be sustained and the financial drawbacks of switching to renewable resources in light of the depleting resources. [4]

Issues

Depletion accounting is complex to implement as nature is not as quantifiable like cars, houses or bread. [4] For depletion accounting to work, appropriate units of natural resources must be established so that natural resources can be viable in the market economy. The main issues that arise when trying to do so are, determining a suitable unit of account, deciding how to deal with "collective" nature of a complete ecosystem, delineating the borderline of the ecosystem and defining the extent of possible duplication when the resource interacts in more than one ecosystem. [4] Some economists want to include measurement of the benefits arising from public goods provided by nature, but currently there are no market indicators of value. [4] Globally, environmental economics has not been able to provide a consensus of measurement units of nature's services.

Minerals depletion

Minerals are needed to provide food, clothing, and housing. A United States Geological Survey (USGS) study found a significant long-term trend over the 20th century for non-renewable resources such as minerals to supply a greater proportion of the raw material inputs to the non-fuel, non-food sector of the economy; an example is the greater consumption of crushed stone, sand, and gravel used in construction. [7]

Large-scale exploitation of minerals began in the Industrial Revolution around 1760 in England and has grown rapidly ever since. Technological improvements have allowed humans to dig deeper and access lower grades and different types of ore over that time. [8] [9] [10] Virtually all basic industrial metals (copper, iron, bauxite, etc.), as well as rare earth minerals, face production output limitations from time to time, [11] because supply involves large up-front investments and is therefore slow to respond to rapid increases in demand. [9]

Minerals projected by some to enter production decline during the next 20 years:

Minerals projected by some to enter production decline during the present century:

Such projections may change, as new discoveries are made [13] and typically misinterpret available data on Mineral Resources and Mineral Reserves. [9] [10]

Oil

Peak oil is the period when the maximum rate of global petroleum extraction is reached, after which the rate of production will undergo a long-term decline. The 2005 Hirsch report concluded that the decreased supply combined with increasing demand will significantly increase the worldwide prices of petroleum derived products, and that most significant will be the availability and price of liquid fuel for transportation.

The Hirsch report, funded by United States Department of Energy, concluded that “The peaking of world oil production presents the U. S. and the world with an unprecedented risk management problem. As peaking is approached, liquid fuel prices and price volatility will increase dramatically, and, without timely mitigation, the social, economic and political costs will be unprecedented. Viable mitigation options exist on both the supply and demand sides, but to have substantial impact, they must be initiated more than a decade in advance of peaking.” [17]

Deforestation

Deforestation is the clearing of forests by cutting or burning of trees and plants in a forested area. As a result of deforestation, presently about one half of the forests that once covered Earth have been destroyed. [18] It occurs for many different reasons, and it has several negative implications on the atmosphere and the quality of the land in and surrounding the forest.

Deforestation is the removal of a forest or stand of trees from land, the wood is harvested as a resource for production of consumer products and firewood for heat. The land then either left to recover and then will be replanted or is converted to non-forest land used as agricultural land or development of urban areas. Deforestation 2074483b.jpg
Deforestation is the removal of a forest or stand of trees from land, the wood is harvested as a resource for production of consumer products and firewood for heat. The land then either left to recover and then will be replanted or is converted to non-forest land used as agricultural land or development of urban areas.

Causes

One of the main causes of deforestation is clearing forests for agricultural reasons. As the population of developing areas, especially near rainforests, increases, the need for land for farming becomes more and more important. [19] For most people, a forest has no value when its resources are not being used, so the incentives to deforest these areas outweigh the incentives to preserve the forests. For this reason, the economic value of the forests is very important for the developing countries. [20]

Environmental impact

Because deforestation is so extensive, it has made several significant impacts on the environment, including:

Deforestation is often cited as a contributor to global warming. Because trees and plants remove carbon dioxide and emit oxygen into the atmosphere, the reduction of forests contribute to about 12% of anthropogenic carbon dioxide emissions. [21] One of the most pressing issues that deforestation creates is soil erosion. The removal of trees causes higher rates of erosion, increasing risks of landslides, which is a direct threat to many people living close to deforested areas. As forests get destroyed, so does the habitat for millions of animals. It is estimated that 80% of the world's known biodiversity lives in the rainforests, and the destruction of these rainforests is accelerating extinction at an alarming rate. [22]

Controlling deforestation

The United Nations and the World Bank created programs such as Reducing Emissions from Deforestation and Forest Degradation (REDD), which works especially with developing countries to use subsidies or other incentives to encourage citizens to use the forest in a more sustainable way. [23] In addition to making sure that emissions from deforestation are kept to a minimum, an effort to educate people on sustainability and helping them to focus on the long-term risks is key to the success of these programs. [24] The New York Declaration on Forests and its associated actions promotes reforestation, which is being encouraged in many countries in an attempt to repair the damage that deforestation has done. [25]

Wetlands

Wetlands are ecosystems that are often saturated by enough surface or groundwater to sustain vegetation that is usually adapted to saturated soil conditions, such as cattails, bulrushes, red maples, wild rice, blackberries, cranberries, and peat moss. [26] Because some varieties of wetlands are rich in minerals and nutrients and provide many of the advantages of both land and water environments they contain diverse species and provide a distinct basis for the food chain. Wetland habitats contribute to environmental health and biodiversity. [26] Wetlands are a nonrenewable resource on a human timescale and in some environments cannot ever be renewed. [27] Recent studies indicate that global loss of wetlands could be as high as 87% since 1700 AD, with 64% of wetland loss occurring since 1900. [27] Some loss of wetlands resulted from natural causes such as erosion, sedimentation, subsidence, and a rise in the sea level. [26]

Wetlands provide environmental services for:

  1. Food and habitat
  2. Improving water quality
  3. Commercial fishing
  4. Floodwater reduction
  5. Shoreline stabilization
  6. Recreation

Resources in wetlands

Some of the world's most successful agricultural areas are wetlands which have been drained an converted to farmland for large-scale agriculture. [26] Large-scale draining of wetlands also occurs for real estate development and urbanization. [28] In contrast, in some cases wetlands are also flooded to be converted to recreational lakes or hydro-power generation. [26] In some countries ranchers have also moved their property onto wetlands for grazing due to the nutrient rich vegetation. [28] Wetlands in Southern America also prove a fruitful resource for poachers, as animals with valuable hides such a jaguars, maned wolves, caimans and snakes are drawn to wetlands. [28] The effect of the removal of large predators is still unknown in South African wetlands. [28]

Humans benefit from wetlands in indirect ways as well. Wetlands act as natural water filters, when runoff from either natural or man-made processes pass through, wetlands can have a neutralizing effect. [29] If a wetland is in between an agricultural zone and a freshwater ecosystem, fertilizer runoff will be absorbed by the wetland and used to fuel the slow processes that occur happen, by the time the water reaches the freshwater ecosystem there won't be enough fertilizer to cause destructive algal blooms that poison freshwater ecosystems. [29]

Bramiana Wetlands Bramiana Wetlands Ierapetra.JPG
Bramiana Wetlands

Non-natural causes of wetland degradation

To preserve the resources extracted from wetlands, current strategies are to rank wetlands and prioritize the conservation of wetlands with more environmental services, create more efficient irrigation for wetlands being used for agriculture and restricting access to wetlands by tourists. [28]

Groundwater

Groundwater flow paths vary greatly in length, depth and travel time from points of recharge to points of discharge in the groundwater system Groundwater flow.svg
Groundwater flow paths vary greatly in length, depth and travel time from points of recharge to points of discharge in the groundwater system

Water is an essential resource needed to survive everyday life. Historically, water has had a profound influence on a nation's prosperity and success around the world. [30] Groundwater is water that is in saturated zones underground, the upper surface of the saturated zone is called the water table. [31] Groundwater is held in the pores and fractures of underground materials like sand, gravel and other rock, these rock materials are called aquifers. [31] Groundwater can either flow naturally out of rock materials or can be pumped out. Groundwater supplies wells and aquifers for private, agricultural, and public use and is used by more than a third of the world's population every day for their drinking water. Globally there is 22.6 million cubic kilometers of groundwater available and only .35 million of that is renewable. [32]

Groundwater as a non-renewable resource

Groundwater is considered to be a non-renewable resource because less than six percent of the water around the world is replenished and renewed on a human timescale of 50 years. [33] People are already using non-renewable water that is thousands of years old, in areas like Egypt they are using water that may have been renewed a million years ago which is not renewable on human timescales. [32] Of the groundwater used for agriculture 16 to 33% is non-renewable. [34] It is estimated that since the 1960s groundwater extraction has more than doubled, which has increased groundwater depletion. [34] Due to this increase in depletion, in some of the most depleted areas use of groundwater for irrigation has become impossible or cost prohibitive. [35]

Environmental impacts

Overusing groundwater, old or young can lower subsurface water levels and dry up streams, which could have a huge effect on ecosystems on the surface. [32] When the most easily recoverable fresh groundwater is removed this leaves a residual with inferior water quality. This is in part from induced leakage from the land surface, confining layers or adjacent aquifers that contain saline or contaminated water. [35] Worldwide the magnitude of groundwater depletion from storage may be so large as to constitute a measurable contributor to sea-level rise. [34]

Mitigation

Currently, societies respond to water-resource depletion by shifting management objectives from location and developing new supplies to augmenting conserving and reallocation of existing supplies. [35] There are two different perspectives to groundwater depletion, the first is that depletion is considered literally and simply as a reduction in the volume of water in the saturated zone, regardless of water quality considerations. [35] A second perspective views depletion as a reduction in the usable volume of fresh groundwater in storage. [35]

Augmenting supplies can mean improving water quality or increasing water quantity. Depletion due to quality considerations can be overcome by treatment, whereas large volume metric depletion can only be alleviated by decreasing discharge or increasing recharge. [35] Artificial recharge of storm flow and treated municipal wastewater, has successfully reversed groundwater declines. [35] In the future improved infiltration and recharge technologies will be more widely used to maximize the capture of runoff and treated wastewater.

Renewable resources

Renewable energy can be collected from renewable resources. The two main sources of renewable energy are solar energy and wind power. The government and scientists are researching and looking upon alternatives to replace the depleting nonrenewable resources. Japan and the U.S. are leading in the department of selling and manufacturing solar powered utilities. [36]

See also

Related Research Articles

Natural resource Resources that exist without actions of humankind

Natural resources are resources that exist without actions of humankind. This includes all valued characteristics such as magnetic, gravitational, electrical properties and forces, etc. On Earth it includes sunlight, atmosphere, water, land along with all vegetation, crops and animal life that naturally subsists upon or within the previously identified characteristics and substances.

Wetland land area that is permanently or seasonally saturated with water

A wetland is a distinct ecosystem that is flooded by water, either permanently or seasonally, where oxygen-free processes prevail. The primary factor that distinguishes wetlands from other land forms or water bodies is the characteristic vegetation of aquatic plants, adapted to the unique hydric soil. Wetlands play a number of functions, including water purification, water storage, processing of carbon and other nutrients, stabilization of shorelines, and support of plants and animals. Wetlands are also considered the most biologically diverse of all ecosystems, serving as home to a wide range of plant and animal life. Whether any individual wetland performs these functions, and the degree to which it performs them, depends on characteristics of that wetland and the lands and waters near it. Methods for rapidly assessing these functions, wetland ecological health, and general wetland condition have been developed in many regions and have contributed to wetland conservation partly by raising public awareness of the functions and the ecosystem services some wetlands provide.

Non-renewable resource a resource that does not renew itself on human time scales

A non-renewable resource is a natural resource that cannot be readily replaced by natural means at a quick enough pace to keep up with consumption. An example is carbon-based fossil fuel. The original organic matter, with the aid of heat and pressure, becomes a fuel such as oil or gas. Earth minerals and metal ores, fossil fuels and groundwater in certain aquifers are all considered non-renewable resources, though individual elements are always conserved.

Renewable resource natural resource which can replenish with the passage of time, either through biological reproduction or other naturally recurring processes

A renewable resource is a natural resource which will replenish to replace the portion depleted by usage and consumption, either through natural reproduction or other recurring processes in a finite amount of time in a human time scale. Renewable resources are a part of Earth's natural environment and the largest components of its ecosphere. A positive life cycle assessment is a key indicator of a resource's sustainability.

Sustainable agriculture Farming relying on as much renewable resources as possible

Sustainable agriculture is farming in sustainable ways, which means meeting society's present food and textile needs, without compromising the ability for current or future generations to meet their needs. It can be based on an understanding of ecosystem services. There are many methods to increase the sustainability of agriculture. When developing agriculture within sustainable food systems, it is important to develop flexible business process and farming practices.

Exploitation of natural resources

The exploitation of natural resources is the use of natural resources for economic growth, sometimes with a negative connotation of accompanying environmental degradation. It started to emerge on an industrial scale in the 19th century as the extraction and processing of raw materials developed much further than it had in preindustrial areas. During the 20th century, energy consumption rapidly increased. Today, about 80% of the world's energy consumption is sustained by the extraction of fossil fuels, which consists of oil, coal and gas. Another non-renewable resource that is exploited by humans is subsoil minerals such as precious metals that are mainly used in the production of industrial commodities. Intensive agriculture is an example of a mode of production that hinders many aspects of the natural environment, for example the degradation of forests in a terrestrial ecosystem and water pollution in an aquatic ecosystem. As the world population rises and economic growth occurs, the depletion of natural resources influenced by the unsustainable extraction of raw materials becomes an increasing concern.

Environmental degradation deterioration of the environment through depletion of resources such as air, water and soil; the destruction of ecosystems; habitat destruction; the extinction of wildlife; and pollution

Environmental degradation is the deterioration of the environment through depletion of resources such as air, water and soil; the destruction of ecosystems; habitat destruction; the extinction of wildlife; and pollution. It is defined as any change or disturbance to the environment perceived to be deleterious or undesirable. As indicated by the I=PAT equation, environmental impact (I) or degradation is caused by the combination of an already very large and increasing human population (P), continually increasing economic growth or per capita affluence (A), and the application of resource-depleting and polluting technology (T).

Sustainable yield

The sustainable yield of natural capital is the ecological yield that can be extracted without reducing the base of capital itself, i.e. the surplus required to maintain ecosystem services at the same or increasing level over time. The term only refers to resources that are renewable in nature as extracting non-renewable resources will always diminish the natural capital. The sustainable yield of a given resource will generally vary over time with the needs of the ecosystem to maintain itself, e.g. a forest that has recently suffered a blight or flooding or fire will require more of its own ecological yield to sustain and re-establish a mature forest. While doing so, the sustainable yield may be much less. The term sustainable yield is most commonly used in forestry, fisheries, and groundwater applications.

Ecological engineering uses ecology and engineering to predict, design, construct or restore, and manage ecosystems that integrate "human society with its natural environment for the benefit of both".

Habitat destruction is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or die, thereby reducing biodiversity and species abundance. Habitat destruction through human activity is mainly for the purpose of harvesting natural resources for industrial production and urbanization. Clearing habitats for agriculture is the principal cause of habitat destruction. Other important causes of habitat destruction include mining, logging, trawling, and urban sprawl. Habitat destruction is currently ranked as the primary cause of species extinction worldwide. The destructive environmental changes include more indirect factors like geological processes, and climate change, introduction of invasive species, ecosystem nutrient depletion, water and noise pollution and others. Loss of habitat can be preceded by an initial habitat fragmentation.

A resource is a source or supply from which a benefit is produced and that has some utility. Resources can broadly be classified upon their availability — they are classified into renewable and non-renewable resources. They can also be classified as actual and potential on the basis of the level of development and use, on the basis of origin they can be classified as biotic and abiotic, and on the basis of their distribution, as ubiquitous and localized. An item becomes a resource with time and developing technology. The benefits of resource utilization may include increased wealth, proper functioning of a system, or enhanced well-being. From a human perspective, a natural resource is anything obtained from the environment to satisfy human needs and wants. From a broader biological or ecological perspective, a resource satisfies the needs of a living organism.

Water scarcity Lack of fresh water resources to meet water demand

Water scarcity is the lack of fresh water resources to meet water demand. It affects every continent and was listed in 2019 by the World Economic Forum as one of the largest global risks in terms of potential impact over the next decade. It is manifested by partial or no satisfaction of expressed demand, economic competition for water quantity or quality, disputes between users, irreversible depletion of groundwater, and negative impacts on the environment. Two-thirds of the global population live under conditions of severe water scarcity at least 1 month of the year. Half a billion people in the world face severe water scarcity all year round. Half of the world's largest cities experience water scarcity.many of people have problems with water scarcity.

Sustainability Process of maintaining change in a balanced fashion

Sustainability is the ability to exist constantly. In the 21st century, it refers generally to the capacity for the biosphere and human civilization to coexist. It is also defined as the process of people maintaining change in a homeostasis balanced environment, in which the exploitation of resources, the direction of investments, the orientation of technological development and institutional change are all in harmony and enhance both current and future potential to meet human needs and aspirations. For many in the field, sustainability is defined through the following interconnected domains or pillars: environment, economic and social, which according to Fritjof Capra is based on the principles of Systems Thinking. Sub-domains of sustainable development have been considered also: cultural, technological and political. According to Our Common Future, Sustainable development is defined as development that "meets the needs of the present without compromising the ability of future generations to meet their own needs." Sustainable development may be the organizing principle of sustainability, yet others may view the two terms as paradoxical.

Water resources Sources of water that are potentially useful

Water resources are natural resources of water that are potentially useful. Uses of water include agricultural, industrial, household, recreational and environmental activities. All living things require water to grow and reproduce.

Sustainability measurement is the quantitative basis for the informed management of sustainability. The metrics used for the measurement of sustainability are still evolving: they include indicators, benchmarks, audits, indexes and accounting, as well as assessment, appraisal and other reporting systems. They are applied over a wide range of spatial and temporal scales.

At the global scale sustainability and environmental management involves managing the oceans, freshwater systems, land and atmosphere, according to sustainability principles.

Mire Wetland terrain without forest cover, dominated by living, peat-forming plants

A mire, peatland or quagmire is a wetland type, dominated by living peat-forming plants. Mires arise because of incomplete decomposition of organic matter, usually litter from vegetation, due to water-logging and subsequent anoxia. All types of mires share the common characteristic of being saturated with water at least seasonally with actively forming peat, while having its own set of vegetation and organisms. Like coral reefs, mires are unusual landforms in that they derive mostly from biological rather than physical processes, and can take on characteristic shapes and surface patterning.

Nature-based solutions Sustainable management and use of nature for tackling socio-environmental challenges

Nature-based solutions (NBS) refers to the sustainable management and use of nature for tackling socio-environmental challenges. The challenges include issues such as climate change, water security, water pollution, food security, human health, and disaster risk management.

Fresh water Naturally occurring water with low amounts of dissolved salts

Fresh water is any naturally occurring water except seawater and brackish water. Fresh water includes water in ice sheets, ice caps, glaciers, icebergs, bogs, ponds, lakes, rivers, streams, and even underground water called groundwater. Fresh water is generally characterized by having low concentrations of dissolved salts and other total dissolved solids. Though the term specifically excludes seawater and brackish water, it does include mineral-rich waters such as chalybeate springs.

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Further reading