Human impact on the environment
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"Anthropogenic" redirects here. It is not to be confused with Anthropogeny or Anthropization.
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Contents
Causes
Technology
The applications of technology often result in unavoidable environmental impacts, which according to the I=PAT equation is measured as resource use or pollution generated per unit GDP. Environmental impacts caused by the application of technology are often perceived as unavoidable for several reasons. First, given that the purpose of many technologies is to exploit, control, or otherwise “improve” upon nature for the perceived benefit of humanity while at the same time the myriad of processes in nature have been optimized and are continually adjusted by evolution, any disturbance of these natural processes by technology is likely to result in negative environmental consequences.[6] Second, the conservation of mass principle and the first law of thermodynamics (i.e., conservation of energy) dictate that whenever material resources or energy are moved around or manipulated by technology, environmental consequences are inescapable. Third, according to the second law of thermodynamics, order can be increased within a system (such as the human economy) only by increasing disorder or entropy outside the system (i.e., the environment). Thus, technologies can create “order” in the human economy (i.e., order as manifested in buildings, factories, transportation networks, communication systems, etc.) only at the expense of increasing “disorder” in the environment. According to a number of studies, increased entropy is likely to be correlated to negative environmental impacts.[7][8][9][10]Agriculture
Main article: Environmental impact of agriculture
The environmental impact of agriculture varies based on the wide
variety of agricultural practices employed around the world. Ultimately,
the environmental impact depends on the production practices of the
system used by farmers. The connection between emissions into the
environment and the farming system is indirect, as it also depends on
other climate variables such as rainfall and temperature.There are two types of indicators of environmental impact: "means-based", which is based on the farmer's production methods, and "effect-based", which is the impact that farming methods have on the farming system or on emissions to the environment. An example of a means-based indicator would be the quality of groundwater, that is effected by the amount of nitrogen applied to the soil. An indicator reflecting the loss of nitrate to groundwater would be effect-based.[11]
The environmental impact of agriculture involves a variety of factors from the soil, to water, the air, animal and soil diversity, people, plants, and the food itself. Some of the environmental issues that are related to agriculture are climate change, deforestation, genetic engineering, irrigation problems, pollutants, soil degradation, and waste.
Fishing
Main article: Environmental impact of fishing
These conservation issues are part of marine conservation, and are addressed in fisheries science programs. There is a growing gap between how many fish are available to be caught and humanity’s desire to catch them, a problem that gets worse as the world population grows.
Similar to other environmental issues, there can be conflict between the fishermen who depend on fishing for their livelihoods and fishery scientists who realize that if future fish populations are to be sustainable then some fisheries must reduce or even close.[12]
The journal Science published a four-year study in November 2006, which predicted that, at prevailing trends, the world would run out of wild-caught seafood in 2048. The scientists stated that the decline was a result of overfishing, pollution and other environmental factors that were reducing the population of fisheries at the same time as their ecosystems were being degraded. Yet again the analysis has met criticism as being fundamentally flawed, and many fishery management officials, industry representatives and scientists challenge the findings, although the debate continues. Many countries, such as Tonga, the United States, Australia and New Zealand, and international management bodies have taken steps to appropriately manage marine resources.[13][14]
Irrigation
Main article: Environmental impact of irrigation
The environmental impact of irrigation includes the changes in quantity and quality of soil and water as a result of irrigation and the ensuing effects on natural and social conditions at the tail-end and downstream of the irrigation scheme.The impacts stem from the changed hydrological conditions owing to the installation and operation of the scheme.
- the downstream river discharge is reduced
- the evaporation in the scheme is increased
- the groundwater recharge in the scheme is increased
- the level of the water table rises
- the drainage flow is increased.
Effects on soil and water quality are indirect and complex, and subsequent impacts on natural, ecological and socio-economic conditions are intricate. In some, but not all instances, water logging and soil salinization can result. However, irrigation can also be used, together with soil drainage, to overcome soil salinization by leaching excess salts from the vicinity of the root zone.[15][16]
Irrigation can also be done extracting groundwater by (tube)wells. As a hydrological result it is found that the level of the water descends. The effects may be water mining, land/soil subsidence, and, along the coast, saltwater intrusion.
Irrigation projects can have large benefits, but the negative side effects are often overlooked.[17][18] Agricultural irrigation technologies such as high powered water pumps, dams, and pipelines are responsible for the large-scale depletion of fresh water resources such as aquifers, lakes, and rivers. As a result of this massive diversion of freshwater, lakes, rivers, and creeks are running dry, severely altering or stressing surrounding ecosystems, and contributing to the extinction of many aquatic species.[19]
Agricultural land loss and soil erosion
Lal and Stewart estimated global loss of agricultural land by degradation and abandonment at 12 million hectares per year.[20] In contrast, according to Scherr, GLASOD (Global Assessment of Human-Induced Soil Degradation, under the UN Environment Programme) estimated that 6 million hectares of agricultural land per year had been lost to soil degradation since the mid-1940s, and she noted that this magnitude is similar to earlier estimates by Dudal and by Rozanov et al.[21] Such losses are attributable not only to soil erosion, but also to salinization, loss of nutrients and organic matter, acidification, compaction, water logging and subsidence.[22] Human-induced land degradation tends to be particularly serious in dry regions. Focusing on soil properties, Oldeman estimated that about 19 million square kilometers of global land area had been degraded; Dregne and Chou, who included degradation of vegetation cover as well as soil, estimated about 36 million square kilometers degraded in the world’s dry regions.[23] Despite estimated losses of agricultural land, the amount of arable land used in crop production globally increased by about 9 percent from 1961 to 2012, and is estimated to have been 1.396 billion hectares in 2012.[24]Global average soil erosion rates are thought to be high, and erosion rates on conventional cropland generally exceed estimates of soil production rates, usually by more than an order of magnitude.[25] In the US, sampling for erosion estimates by the US NRCS (Natural Resources Conservation Service) is statistically based, and estimation uses the Universal Soil Loss Equation and Wind Erosion Equation. For 2010, annual average soil loss by sheet, rill and wind erosion on non-federal US land was estimated to be 10.7 t/ha on cropland and 1.9 t/ha on pasture land; the average soil erosion rate on US cropland had been reduced by about 34 percent since 1982.[26] No-till and low-till practices have become increasingly common on North American cropland used for production of grains such as wheat and barley. On uncultivated cropland, the recent average total soil loss has been 2.2 t/ha per year.[26] In comparison with agriculture using conventional cultivation, it has been suggested that, because no-till agriculture produces erosion rates much closer to soil production rates, it could provide a foundation for sustainable agriculture.[25]
Meat production
Main article: Environmental impact of meat production
Environmental impacts associated with meat production include use of
fossil energy, water and land resources, greenhouse gas emissions, and
in some instances, rainforest clearing, water pollution and species
endangerment, among other adverse effects.[27]Steinfeld et al. of the FAO estimated that 18 percent of global anthropogenic GHG (greenhouse gas) emissions (estimated as 100-year carbon dioxide equivalents) are associated in some way with livestock production.[27] However, many estimates use different sectoral assignment of some emissions. For example, a more recent FAO analysis estimated that all agriculture, including the livestock sector, in 2011 accounted for 12 percent of global anthropogenic GHG emissions expressed as 100-year carbon dioxide equivalents.[28] Similarly, the Intergovernmental Panel on Climate Change has estimated that about 10 to 12 percent of global anthropogenic GHG emissions (expressed as 100-year carbon dioxide equivalents) were assignable to all of agriculture, including the livestock sector, in 2005[29] and again in 2010.[30] The percentage assignable to livestock would be some fraction of the percentage for agriculture. The amount assignable to meat production would be some fraction of that assigned to livestock. FAO data indicate that meat accounted for 26 percent of global livestock product tonnage in 2011.[24]
Globally, enteric fermentation (mostly in ruminant livestock) accounts for about 27 percent of anthropogenic methane emissions,[31] Despite methane’s 100-year global warming potential, recently estimated at 28 without and 34 with climate carbon feedbacks,[31] methane emission is currently contributing relatively little to global warming. Over the decade 2000 through 2009, atmospheric methane content increased by an average of only 6 Tg per year (because nearly all natural and anthropogenic methane emission was offset by degradation), while atmospheric carbon dioxide increased by nearly 15,000 Tg per year.[31] At the currently estimated rate of methane degradation, slight reduction of anthropogenic methane emissions, to about 98 percent of that decade’s average, would be expected to result in no further increase of atmospheric methane content. Although reduction of methane emissions would have a rapid effect on warming, the expected effect would be small.[32] Other anthropogenic GHG emissions associated with livestock production include carbon dioxide from fossil fuel consumption (mostly for production, harvesting and transport of feed), and nitrous oxide emissions associated with use of nitrogenous fertilizers, growing of nitrogen-fixing legume vegetation and manure management. Management practices that can mitigate GHG emissions from production of livestock and feed have been identified.[33][34][35][36][37]
Livestock production, including feed production and grazing, uses about 30 percent of the earth’s ice-free terrestrial surface: about 26 percent for grazing and about 4 percent for other feed production.[27] The intensity and duration of grazing use vary greatly[38] and these, together with terrain, vegetation and climate, influence the nature and importance of grazing’s environmental impact, which can range from severe to negligible, and in some cases (as noted below) beneficial. Excessive use of vegetation by grazing can be especially conducive to land degradation in dry areas.[39]
Considerable water use is associated with meat production, mostly because of water used in production of vegetation that provides feed. There are several published estimates of water use associated with livestock and meat production, but the amount of water use assignable to such production is seldom estimated. For example, “green water” use is evapotranspirational use of soil water that has been provided directly by precipitation; and “green water” has been estimated to account for 94 percent of global beef cattle production’s “water footprint”,[40] and on rangeland, as much as 99.5 percent of the water use associated with beef production is “green water”. However, it would be misleading simply to assign that associated rangeland green water use to beef production, partly because that evapotranspirational use occurs even in the absence of cattle. Even when cattle are present, most of that associated water use can be considered assignable to production of terrestrial environmental values, because it produces root and residue biomass important for erosion control, stabilization of soil structure, nutrient cycling, carbon sequestration, support of numerous primary consumers, many of which support higher trophic levels, etc. Withdrawn water (from surface and groundwater sources) is used for livestock watering, and in some cases is also used for irrigation of forage and feed crops. Whereas all irrigation in the US (including loss in conveyance) is estimated to account for about 38 percent of US withdrawn freshwater use,[41] irrigation water for production of livestock feed and forage has been estimated to account for about 9 percent;[42] other withdrawn freshwater use for the livestock sector (for drinking, washdown of facilities, etc.) is estimated at about 0.7 percent.[41] Because of the preponderance of non-meat products from the livestock sector[24] only some fraction of this water use is assignable to meat production.
Impairment of water quality by manure and other substances in runoff and infiltrating water is a concern, especially where intensive livestock production is carried out. In the US, in a comparison of 32 industries, the livestock industry was found to have a relatively good record of compliance with environmental regulations pursuant to the Clean Water Act and Clean Air Act,[43] but pollution issues from large livestock operations can sometimes be serious where violations occur. Various measures have been suggested by the US Environmental Protection Agency, among others, which can help reduce livestock damage to streamwater quality and riparian environments.[44]
Data of a USDA study indicate that, in 2002, about 0.6 percent of non-solar energy use in the United States was accounted for by production of meat-producing livestock and poultry.[45] This estimate included embodied energy used in production, such as energy used in manufacture and transport of fertilizer for feed production. (Non-solar energy is specified, because solar energy is used in such processes as photosynthesis and hay-drying.)
Changes in livestock production practices influence the environmental impact of meat production, as illustrated by some beef data. In the US beef production system, practices prevailing in 2007 are estimated to have involved 8.6 percent less fossil fuel use, 16.3 percent less greenhouse gas emissions (estimated as 100-year carbon dioxide equivalents), 12.1 percent less withdrawn water use and 33.0 percent less land use, per unit mass of beef produced, than in 1977.[46] From 1980 to 2012 in the US, while population increased by 38 percent, the small ruminant inventory decreased 42 percent, the cattle-and-calves inventory decreased 17 percent, and methane emissions from livestock decreased 18 percent;[24] yet despite the reduction in cattle numbers, US beef production increased over that period.[47]
Some impacts of meat-producing livestock may be considered environmentally beneficial. These include waste reduction by conversion of human-inedible crop residues to food, use of livestock as an alternative to herbicides for control of invasive and noxious weeds and other vegetation management,[48] use of animal manure as fertilizer as a substitute for those synthetic fertilizers that require considerable fossil fuel use for manufacture, grazing use for wildlife habitat enhancement,[49] and carbon sequestration in response to grazing practices,[50][51] among others.
Palm oil
Main article: Social and environmental impact of palm oil
Introductions and invasive species
Introductions of species, particularly plants into new areas, by whatever means and for whatever reasons have brought about major and permanent changes to the environment over large areas. Examples include the introduction of Caulerpa taxifolia into the Mediterranean, the introduction of oat species into the California grasslands, and the introduction of privet, kudzu, and purple loosestrife to North America. Rats, cats, and goats have radically altered biodiversity in many islands. Additionally, introductions have resulted in genetic changes to native fauna where interbreeding has taken place, as with buffalo with domestic cattle, and wolves with domestic dogs.Energy industry
Main article: Environmental impact of the energy industry
The environmental impact of energy harvesting and consumption is diverse. In recent years there has been a trend towards the increased commercialization of various renewable energy sources.In the real world of consumption of fossil fuel resources which lead to global warming and climate change. However, little change is being made in many parts of the world. If the peak oil theory proves true, more explorations of viable alternative energy sources, could be more friendly to the environment.
Rapidly advancing technologies can achieve a transition of energy generation, water and waste management, and food production towards better environmental and energy usage practices using methods of systems ecology and industrial ecology.[53][54]
Biodiesel
Main article: Environmental impact of biodiesel
The environmental impact of biodiesel
includes energy use, greenhouse gas emissions and some other kinds of
pollution. A joint life cycle analysis by the US Department of
Agriculture and the US Department of Energy found that substituting 100
percent biodiesel for petroleum diesel in buses reduced life cycle
consumption of petroleum by 95 percent. Biodiesel reduced net emissions
of carbon dioxide by 78.45 percent, compared with petroleum diesel. In
urban buses, biodiesel reduced particulate emissions 32 percent, carbon
monoxide emissions 35 percent, and emissions of sulfur oxides 8 percent,
relative to life cycle emissions associated with use of petroleum
diesel. Life cycle emissions of hydrocarbons were 35 percent higher and
emission of various nitrogen oxides (NOx) were 13.5 percent higher with
biodiesel.[55]
Life cycle analyses by the Argonne National Laboratory have indicated
reduced fossil energy use and reduced greenhouse gas emissions with
biodiesel, compared with petroleum diesel use.[56]
Biodiesel derived from various vegetable oils (e.g. canola or soybean
oil), is readily biodegradable in the environment compared with
petroleum diesel.[57]Coal mining and burning
Main article: Environmental impact of coal mining and burning
The environmental impact of coal mining and burning is diverse.[58] Legislation passed by the US Congress in 1990 required the United States Environmental Protection Agency (EPA) to issue a plan to alleviate toxic pollution from coal-fired
power plants. After delay and litigation, the EPA now has a
court-imposed deadline of March 16, 2011, to issue its report.Electricity generation
Main article: Environmental impact of electricity generation
The environmental impact of electricity generation is significant because modern society uses large amounts of electrical power. This power is normally generated at power plants that convert some other kind of energy into electricity. Each such system has advantages and disadvantages, but many of them pose environmental concerns.Nuclear power
Main article: Environmental impact of nuclear power
The environmental impact of nuclear power results from the nuclear fuel cycle processes including mining, processing, transporting and storing fuel and radioactive fuel waste. Released radioisotopes
pose a health danger to human populations, animals and plants as
radioactive particles enter organisms through various transmission
routes.Radiation is a carcinogen and causes numerous effects on living organisms and systems. The environmental impacts of nuclear power plant releases such as the Chernobyl disaster, the Fukushima Daiichi nuclear disaster and the Three Mile Island accident, among others, persist indefinitely. The radioactive decay rate of particles varies greatly, dependent upon the atomic properties of a particular isotope. Radioactive Plutonium-244 has a half-life of 80.8 million years, which indicates the time duration required for half of a given sample to decay.[59]
Oil shale industry
Main article: Environmental impact of the oil shale industry
Petroleum
Main article: Environmental impact of petroleum
The environmental impact of petroleum is often negative because it is toxic to almost all forms of life. The possibility of climate change
exists. Petroleum, commonly referred to as oil, is closely linked to
virtually all aspects of present society, especially for transportation
and heating for both homes and for commercial activities.Reservoirs
Main article: Environmental impact of reservoirs
Dams and the reservoirs can be used to supply drinking water, generate hydroelectric power, increasing the water supply for irrigation, provide recreational opportunities and to improve certain aspects of the environment. However, adverse environmental and sociological impacts have also been identified during and after many reservoir constructions. Although the impact varies greatly between different dams and reservoirs, common criticisms include preventing sea-run fish from reaching their historical mating grounds, less access to water downstream, and a smaller catch for fishing communities in the area. Advances in technology have provided solutions to many negative impacts of dams but these advances are often not viewed as worth investing in if not required by law or under the threat of fines. Whether reservoir projects are ultimately beneficial or detrimental—to both the environment and surrounding human populations— has been debated since the 1960s and probably long before that. In 1960 the construction of Llyn Celyn and the flooding of Capel Celyn provoked political uproar which continues to this day. More recently, the construction of Three Gorges Dam and other similar projects throughout Asia, Africa and Latin America have generated considerable environmental and political debate.
Wind power
Main article: Environmental impact of wind power
There are reports of bird and bat mortality at wind turbines, as there are around other artificial structures. The scale of the ecological impact may[62] or may not[63] be significant, depending on specific circumstances. Prevention and mitigation of wildlife fatalities, and protection of peat bogs,[64] affect the siting and operation of wind turbines.
There are conflicting reports about the effects of noise on people who live very close to a wind turbine.
Light pollution
Main article: Ecological light pollution
Manufactured products
Cleaning agents
Main article: Environmental impact of cleaning agents
The environmental impact of cleaning agents is diverse. In recent years, measures have been taken to reduce these effects.Nanotechnology
Main article: Environmental impact of nanotechnology
Nanotechnology's
environmental impact can be split into two aspects: the potential for
nanotechnological innovations to help improve the environment, and the
possibly novel type of pollution that nanotechnological materials might
cause if released into the environment. As nanotechnology is an emerging
field, there is great debate regarding to what extent industrial and
commercial use of nanomaterials will affect organisms and ecosystems.Leather
Main article: Environmental impact of leather
Paint
Main article: Environmental impact of paint
The environmental impact of paint is diverse. Traditional painting materials and processes can have harmful effects on the environment, including those from the use of lead
and other additives. Measures can be taken to reduce environmental
impact, including accurately estimating paint quantities so that wastage
is minimized, use of paints, coatings, painting accessories and
techniques that are environmentally preferred. The United States Environmental Protection Agency guidelines and Green Star ratings are some of the standards that can be applied.Paper
Main article: Environmental impact of paper
Pesticides
Main article: Environmental impact of pesticides
The environmental impact of pesticides
is often greater than what is intended by those who use them. Over 98%
of sprayed insecticides and 95% of herbicides reach a destination other
than their target species, including nontarget species, air, water,
bottom sediments, and food.[67]
Pesticide contaminates land and water when it escapes from production
sites and storage tanks, when it runs off from fields, when it is
discarded, when it is sprayed aerially, and when it is sprayed into
water to kill algae.[68]The amount of pesticide that migrates from the intended application area is influenced by the particular chemical's properties: its propensity for binding to soil, its vapor pressure, its water solubility, and its resistance to being broken down over time.[69] Factors in the soil, such as its texture, its ability to retain water, and the amount of organic matter contained in it, also affect the amount of pesticide that will leave the area.[69] Some pesticides contribute to global warming and the depletion of the ozone layer.[70]
Pharmaceuticals and personal care products
The environmental impact of pharmaceuticals and personal care products (PPCPs) is largely speculative. PPCPs are substances used by individuals for personal health or cosmetic reasons and the products used by agribusiness to boost growth or health of livestock. PPCPs have been detected in water bodies throughout the world. The effects of these chemicals on humans and the environment are not yet known, but to date there is no scientific evidence that they have an impact on human health.[71]Mining
Main article: Environmental impact of mining
Transport
Main article: Environmental impact of transport
Environmental regulations in developed countries have reduced the individual vehicles emission; however, this has been offset by an increase in the number of vehicles, and more use of each vehicle.[74] Some pathways to reduced the carbon emissions of road vehicles considerably have been studied.[76] Energy use and emissions vary largely between modes, causing environmentalists to call for a transition from air and road to rail and human-powered transport, and increase transport electrification and energy efficiency.
Other environmental impacts of transport systems include traffic congestion and automobile-oriented urban sprawl, which can consume natural habitat and agricultural lands. By reducing transportation emissions globally, it is predicted that there will be significant positive effects on Earth's air quality, acid rain, smog and climate change.[77]
The health impact of transport emissions is also of concern. A recent survey of the studies on the effect of traffic emissions on pregnancy outcomes has linked exposure to emissions to adverse effects on gestational duration and possibly also intrauterine growth.[78]
Aviation
Main article: Environmental impact of aviation
The environmental impact of aviation occurs because aircraft engines emit noise, particulates, and gases which contribute to climate change[79][80] and global dimming.[81] Despite emission reductions from automobiles and more fuel-efficient and less polluting turbofan and turboprop engines, the rapid growth of air travel in recent years contributes to an increase in total pollution attributable to aviation. In the EU, greenhouse gas emissions from aviation increased by 87% between 1990 and 2006.[82] Among other factors leading to this phenomenon are the increasing number of hypermobile travellers[83] and social factors that are making air travel commonplace, such as frequent flyer programs.[83]There is an ongoing debate about possible taxation of air travel and the inclusion of aviation in an emissions trading scheme, with a view to ensuring that the total external costs of aviation are taken into account.[84]
Roads
Main article: Environmental impact of roads
The environmental impact of roads includes the local effects of highways (public roads) such as on noise, light pollution, water pollution, habitat destruction/disturbance and local air quality; and the wider effects including climate change from vehicle emissions. The design, construction and management of roads, parking and other related facilities as well as the design and regulation of vehicles can change the impacts to varying degrees.Shipping
Main article: Environmental impact of shipping
The environmental impact of shipping includes greenhouse gas emissions and oil pollution. In 2007, carbon dioxide emissions from shipping were estimated at 4 to 5% of the global total, and estimated by the International Maritime Organisation (IMO) to rise by up to 72% by 2020 if no action is taken.[85]
There is also a potential for introducing invasive species into new
areas through shipping, usually by attaching themselves to the ship's
hull.The First Intersessional Meeting of the IMO Working Group on Greenhouse Gas Emissions[86] from Ships took place in Oslo, Norway on 23–27 June 2008. It was tasked with developing the technical basis for the reduction mechanisms that may form part of a future IMO regime to control greenhouse gas emissions from international shipping, and a draft of the actual reduction mechanisms themselves, for further consideration by IMO’s Marine Environment Protection Committee (MEPC).[87]
War
Main article: Environmental impact of war
Effects
Biodiversity
Further information: Biodiversity § Threats
Human impact on biodiversity is significant, humans have caused the extinction of many species, including the dodo and, potentially, large megafaunal species during the last ice age.
Though most experts agree that human beings have accelerated the rate
of species extinction, the exact degree of this impact is unknown,
perhaps 100 to 1000 times the normal background rate of extinction.[88][89]
Some authors have postulated that without human interference the
biodiversity of this planet would continue to grow at an exponential
rate.[1]Coral reefs
Main article: Human impact on coral reefs
Human impact on coral reefs is significant. Coral reefs are dying around the world.[90] In particular, coral mining, pollution (organic and non-organic), overfishing, blast fishing and the digging of canals
and access into islands and bays are serious threats to these
ecosystems. Coral reefs also face high dangers from pollution, diseases,
destructive fishing practices and warming oceans.[91]
In order to find answers for these problems, researchers study the
various factors that impact reefs. The list of factors is long,
including the ocean's role as a carbon dioxide sink, atmospheric changes, ultraviolet light, ocean acidification, biological virus, impacts of dust storms carrying agents to far flung reefs, pollutants, algal blooms and others. Reefs are threatened well beyond coastal areas.General estimates show approximately 10% world's coral reefs are already dead.[92][93][94] It is estimated that about 60% of the world's reefs are at risk due to destructive, human-related activities. The threat to the health of reefs is particularly strong in Southeast Asia, where 80% of reefs are endangered.
Carbon cycle
Global warming is the result of increasing atmospheric carbon dioxide concentrations which is caused primarily by the combustion of fossil energy sources such as petroleum, coal, and natural gas, and to an unknown extent by destruction of forests, increased methane, volcanic activity and cement production. Such massive alteration of the global carbon cycle has only been possible because of the availability and deployment of advanced technologies, ranging in application from fossil fuel exploration, extraction, distribution, refining, and combustion in power plants and automobile engines. Potential negative environmental impacts caused by increasing atmospheric carbon dioxide concentrations are rising global air temperatures, altered hydrogeological cycles resulting in more frequent and severe droughts, storms, and floods, as well as sea level rise and ecosystem disruption.[95]Nitrogen cycle
Main article: Human impact on the nitrogen cycle
Human impact on the nitrogen cycle is diverse. Agricultural and industrial nitrogen (N) inputs to the environment currently exceed inputs from natural N fixation.[96][97] As a consequence of anthropogenic inputs, the global nitrogen cycle (Fig. 1) has been significantly altered over the past century. Global atmospheric nitrous oxide (N2O) mole fractions have increased from a pre-industrial value of ~270 nmol/mol to ~319 nmol/mol in 2005.[98] Human activities account for over one-third of N2O emissions, most of which are due to the agricultural sector.[98]Effects on human health
Further information: Effects of pollution on humans and Effects of global warming on human health
See also
References
Notes
Further reading
- Commoner, B. (1971). The Closing Circle: Nature, Man, and Technology. Random House, ISBN 039442350X.
- Goudie, Andrew (2006). The human impact on the natural environment: past, present, and future. Wiley-Blackwell. ISBN 9781405127042.
- Huesemann, M.H., and J.A. Huesemann (2011). Technofix: Why Technology Won’t Save Us or the Environment, New Society Publishers, ISBN 0865717044.
- The Garden of Our Neglect: How Humans Shape the Evolution of Other Species July 5, 2012 Scientific American
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