Resource Depletion - Resource Depletion

Resource depletion  - resource depletion

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.

Resource depletion is most commonly used in reference to farming, fishing, mining, water usage, and consumption of fossil fuels.

Resource depletion  - resource depletion
Causes

  • Aquifer depletion
  • Habitat degradation leads to the loss of biodiversity (i.e. species and ecosystems with its ecosystem services)
  • Irrigation
  • Mining for fossil fuels and minerals
  • Overconsumption, excessive or unnecessary use of resources
  • Overpopulation
  • Pollution or contamination of resources
  • Slash-and-burn agricultural practices, currently occurring in many developing countries
  • Soil erosion
  • Technological and industrial development
  • Deforestation

Resource depletion  - resource depletion
Minerals

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.

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. Virtually all basic industrial metals (copper, iron, bauxite, etc.), as well as rare earth minerals, face production output limitations from time to time, because supply involves large up-front investments and is therefore slow to respond to rapid increases in demand.

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

  • Gas (2023)
  • Copper (2024). Data from the United States Geological Survey (USGS) suggest that it is very unlikely that copper production will peak before 2040.
  • Zinc Developments in hydrometallurgy have transformed non-sulphide zinc deposits (largely ignored until now) into large low cost reserves.

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

  • Aluminium (2057)
  • Coal (2060)
  • Iron (2068)

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

Resource depletion  - resource depletion
Oil

Peak oil is the period when the maximum rate of global petroleum extraction is reached, after which the rate of production enters terminal decline. It relates to a long-term decline in the available supply of petroleum. This, combined with increasing demand, will significantly increase the worldwide prices of petroleum derived products. Most significant will be the availability and price of liquid fuel for transportation.

The United States Department of Energy in the Hirsch report indicates 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 economic, social, 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.”

Resource depletion  - resource depletion
Deforestation

Deforestation is the clearing of forests by logging 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. 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.

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. For most people, a forest has no value when its resources aren’t 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.

Environmental impact

Because deforestation is so extensive, it has made several significant impacts on the environment, including carbon dioxide in the atmosphere, changing the water cycle, an increase in soil erosion, and a decrease in biodiversity. Deforestation is often cited as a cause of 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. 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.

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. 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. 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.

Resource depletion  - resource depletion
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. 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.

Traditionally, wetlands were assumed to be useless so it was not a large concern when they were being dug up for settlements, agricultural use etc.. It is now believed that the wetland habitats contribute to a environmental health and biodiversity.

In the USA, less than half of the wetlands that still existed in the 1600s have vanished.

Wetlands provide environmental services for:

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

Some loss of wetlands resulted from natural causes such as erosion, sedimentation (the buildup of soil by the settling of fine particles over a long period of time), subsidence (the sinking of land because of diminishing underground water supplies), and a rise in the sea level.

Nonnatural causes of wetland degradation and loss include:

  • Hydrologic alteration
    • drainage
    • dredging
    • stream channelization
    • ditching
    • levees
    • deposition of fill material
    • stream diversion
    • groundwater drainage
    • impoundment
  • Urbanization and urban development
  • Marinas/boats
  • Industrialization and industrial development
  • Agriculture
  • Silviculture/Timber harvest
  • Mining
  • Atmospheric deposition

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