Old page wikitext, before the edit (old_wikitext ) | ''''Habitat destruction''' is the process in which natural [[habitat]] is rendered unable to support the species present. In this process, the organisms that previously used the site are displaced or destroyed, reducing [[biodiversity]].<ref name="SahneyBentonFerry2010LinksDiversityVertebrates">{{ cite journal | url=http://geology.geoscienceworld.org/cgi/content/abstract/38/12/1079 | author= Sahney, S., Benton, M.J. & Falcon-Lang, H.J. | year=2010 | title= Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euram eri ca | journal=Geology | volume = 38 | pages = 1079–1082 | format=PDF | doi=10.1130/G31182.1 | issue=12}}</ref> Habitat destruction by human activity is mainly for the purpose of harvesting [[natural resources]] for industry 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.<ref>Pimm & Raven, 2000, pp. 843-845</ref> It is a process of natural environmental change that may be caused by [[habitat fragmentation]], geological processes, [[climate change]]<ref name="SahneyBentonFerry2010LinksDiversityVertebrates"/> or by human activities such as the introduction of [[invasive species]], ecosystem nutrient depletion, and other human activities.
The terms '''habitat loss''' and '''habitat reduction''' are also used in a wider sense, including loss of habitat from other factors, such as [[water pollution|water]] and [[noise pollution]].
==Impacts on organisms==
In the simplest term, when a habitat is destroyed, the plants, animals, and other organisms that occupied the habitat have a reduced [[carrying capacity]] so that populations decline and [[extinction]] becomes more likely.<ref>Scholes & Biggs, 2004</ref> Perhaps the greatest threat to organisms and biodiversity is the process of habitat loss.<ref>Barbault & Sastrapradja, 1995</ref> Temple (1986) found that 82% of [[Endangered species|endangered bird species]] were significantly threatened by habitat loss. Most amphibian species are also threatened by habitat loss<ref>{{cite journal|last1=Beebee|first1=Trevor J.C.|last2=Griffiths|first2=Richard A.|title=The amphibian decline crisis: A watershed for conservation biology?|journal=Biological Conservation|date=31 May 2005|volume=125|issue=3|page=271|doi=10.1016/j.biocon.2005.04.009|url=http://www.sciencedirect.com/science/article/pii/S0006320705001825}}</ref>, and some species are now only breeding in modified habitat<ref>{{cite journal|last1=Borzée|first1=Amaël|last2=Jang|first2=Yikweon|title=Description of a seminatural habitat of the endangered Suweon treefrog Hyla suweonensis|journal=Animal Cells and Systems|date=28 April 2015|volume=19|issue=3|page=216|doi=10.1080/19768354.2015.1028442|url=http://www.tandfonline.com/doi/abs/10.1080/19768354.2015.1028442}}</ref>. [[endemism|Endemic]] organisms with limited ranges are most affected by habitat destruction, mainly because these organisms are not found anywhere else within the world and thus, have less chance of recovering. Many endemic organisms have very specific requirements for their survival that can only be found within a certain ecosystem, resulting in their extinction. Extinction may also take place very long after the destruction of habitat, a phenomenon known as [[extinction debt]]. Habitat destruction can also decrease the range of certain organism populations. This can result in the reduction of genetic diversity and perhaps the production of [[infertile]] youths, as these organisms would have a higher possibility of mating with related organisms within their population, or different species. One of the most famous examples is the impact upon China's [[giant panda]], once found across the nation. Now it is only found in fragmented and isolated regions in the southwest of the country, as a result of widespread [[deforestation]] in the 20th century.<ref>[http://pulitzercenter.org/reporting/china-sichuan-panda-deforestation-habitat-mountain-conservation The Panda's Forest: Biodiversity Loss]</ref>
==Geography==
[[File:Bolivia-Deforestation-EO.JPG|thumb|right|Satellite photograph of deforestation in Bolivia. Originally dry tropical forest, the land is being cleared for [[soybean]] cultivation.<ref>{{cite web
| title = Tierras Bajas Deforestation, Bolivia
| work = Newsroom. Photo taken from the International Space Station on April 16, 2001
| publisher = [[NASA Earth Observatory]]
| date = 2001-04-16
| url = http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=4842
| accessdate = 2008-08-11
}}</ref>]]
[[Biodiversity hotspot]]s are chiefly [[tropical]] regions that feature high concentrations of [[Endemism|endemic]] species and, when all hotspots are combined, may contain over half of the world’s [[Terrestrial animal|terrestrial]] species.<ref name="Cincotta">Cincotta & Engelman, 2000</ref> These hotspots are suffering from habitat loss and destruction.
Most of the natural habitat on islands and in areas of high human population density has already been destroyed (WRI, 2003). Islands suffering extreme habitat destruction include [[New Zealand]], [[Madagascar]], the [[Philippines]], and [[Japan]].<ref name="Primack">Primack, 2006</ref> South and East Asia — especially [[China]], [[India]], [[Malaysia]], [[Indonesia]], and Japan — and many areas in [[West Africa]] have extremely dense human populations that allow little room for natural habitat. Marine areas close to highly populated [[coast]]al cities also face degradation of their [[coral reef]]s or other marine habitat. These areas include the eastern coasts of Asia and Africa, northern coasts of [[South America]], and the [[Caribbean Sea]] and its associated [[island]]s.<ref name="Primack"/>
Regions of un[[sustainable agriculture]] or unstable governments, which may go hand-in-hand, typically experience high rates of habitat destruction. [[Central America]], [[Sub-Saharan Africa]], and the [[Amazonian tropical rainforest]] areas of [[South America]] are the main regions with unsustainable agricultural practices and/or government mismanagement.<ref name="Primack"/>
Areas of high agricultural output tend to have the highest extent of habitat destruction. In the U.S., less than 25% of native vegetation remains in many parts of the [[Eastern United States|East]] and [[Midwestern United States|Midwest]].<ref name="Stein">Stein et al., 2000</ref> Only 15% of land area remains unmodified by human activities in all of Europe.<ref name="Primack"/>
==Ecosystems==
[[File:Lacanja burn.JPG|thumb|Jungle burned for agriculture in southern Mexico]]
[[Tropical rainforest]]s have received most of the attention concerning the destruction of habitat. From the approximately 16 million square kilometers of tropical rainforest habitat that originally existed worldwide, less than 9 million square kilometers remain today.<ref name="Primack"/> The current rate of [[deforestation]] is 160,000 square kilometers per year, which equates to a loss of approximately 1% of original forest habitat each year.<ref name="Laurance">Laurance, 1999</ref>
Other forest [[ecosystem]]s have suffered as much or more destruction as tropical [[rainforest]]s. [[Farming]] and [[logging]] have severely disturbed at least 94% of [[Temperate broadleaf and mixed forests|temperate broadleaf forests]]; many [[old growth forest]] stands have lost more than 98% of their previous area because of human activities.<ref name="Primack"/> [[Tropical and subtropical dry broadleaf forests|Tropical deciduous dry forests]] are easier to [[Slash and burn|clear and burn]] and are more suitable for agriculture and [[cattle ranching]] than tropical rainforests; consequently, less than 0.1% of [[Tropical and subtropical dry broadleaf forests|dry forests in Central America's Pacific Coast]] and less than 8% in [[Madagascar dry deciduous forests|Madagascar]] remain from their original extents.<ref name="Laurance"/>
[[File:Farmland-batang bungo.jpg|thumb|left|Farmers near newly cleared land within Taman Nasional Kerinci Seblat ([[Kerinci Seblat National Park]]), [[Sumatra]].]]
Plains and [[desert]] areas have been degraded to a lesser extent. Only 10-20% of the world's [[drylands]], which include [[temperate grasslands, savannas, and shrublands]], [[Scrubland|scrub]], and [[Temperate deciduous forest|deciduous forests]], have been somewhat degraded.<ref>Kauffman & Pyke, 2001</ref> But included in that 10-20% of land is the approximately 9 million square kilometers of seasonally dry-lands that humans have converted to deserts through the process of desertification.<ref name="Primack"/> The [[tallgrass prairie]]s of North America, on the other hand, have less than 3% of natural habitat remaining that has not been converted to farmland.<ref>White et al., 2000</ref>
[[Wetland]]s and marine areas have endured high levels of habitat destruction. More than 50% of wetlands in the U.S. have been destroyed in just the last 200 years.<ref name="Stein"/> Between 60% and 70% of European wetlands have been completely destroyed.<ref>Ravenga et al., 2000</ref> About one-fifth (20%) of marine coastal areas have been highly modified by humans.<ref>Burke et al., 2000</ref> One-fifth of coral reefs have also been destroyed, and another fifth has been severely degraded by [[overfishing]], pollution, and [[invasive species]]; 90% of the Philippines’ coral reefs alone have been destroyed.<ref name="MEA">MEA, 2005</ref> Finally, over 35% [[Coastal ecosystems|mangrove ecosystems]] worldwide have been destroyed.<ref name="MEA"/>
{{clear}}
==Natural causes==
Habitat destruction through natural processes such as volcanism, [[fire]], and climate change is well documented in the fossil record.<ref name="SahneyBentonFerry2010LinksDiversityVertebrates"/> One study shows that habitat fragmentation of tropical rainforests in Euramerica 300 million years ago led to a great loss of amphibian diversity, but simultaneously the drier climate spurred on a burst of diversity among reptiles.<ref name="SahneyBentonFerry2010LinksDiversityVertebrates"/>
==Human causes==
[[File:Amazonie deforestation.jpg|thumb|Deforestation and roads in Amazonia, the [[Amazon Rainforest]].]]
Habitat destruction caused by humans includes [[land conversion]] from forests, etc. to [[arable land]], [[urban sprawl]], [[Public works|infrastructure development]], and other anthropogenic changes to the characteristics of land. Habitat degradation, fragmentation, and [[pollution]] are aspects of habitat destruction caused by humans that do not necessarily involve over destruction of habitat, yet result in habitat collapse. [[Desertification]], [[deforestation]], and [[Coral bleaching|coral reef degradation]] are specific types of habitat destruction for those areas ([[desert]]s, [[forest]]s, [[coral reef]]s).
Geist and Lambin (2002) assessed 152 case studies of net losses of tropical forest cover to determine any patterns in the proximate and underlying causes of tropical deforestation. Their results, yielded as percentages of the case studies in which each parameter was a significant factor, provide a quantitative prioritization of which proximate and underlying causes were the most significant. The proximate causes were clustered into broad categories of [[agricultural expansion]] (96%), [[infrastructure expansion]] (72%), and [[wood extraction]] (67%). Therefore, according to this study, [[forest conversion]] to agriculture is the main land use change responsible for tropical deforestation. The specific categories reveal further insight into the specific causes of tropical deforestation: transport extension (64%), commercial wood extraction (52%), [[permanent cultivation]] (48%), [[cattle ranching]] (46%), shifting ([[slash and burn]]) cultivation (41%), [[subsistence agriculture]] (40%), and [[fuel wood]] extraction for domestic use (28%). One result is that [[shifting cultivation]] is not the primary cause of deforestation in all world regions, while transport extension (including the [[Road construction|construction of new roads]]) is the largest single proximate factor responsible for deforestation.<ref name="Geist"/>
==Drivers==
[[File:Crowded Nanjing Road in Shanghai.jpeg|thumb|Nanjing Road in Shanghai]]
While the above-mentioned activities are the proximal or direct causes of habitat destruction in that they actually destroy habitat, this still does not identify why humans destroy habitat. The forces that cause humans to destroy habitat are known as ''drivers'' of habitat destruction. [[Demographic]], economic, sociopolitical, scientific and technological, and cultural drivers all contribute to habitat destruction.<ref name="MEA"/>
Demographic drivers include the [[Human overpopulation|expanding human population]]; rate of [[Population growth|population increase]] over time; [[Population density|spatial distribution]] of people in a given area ([[List of urban areas by population|urban]] versus rural), ecosystem type, and country; and the combined effects of poverty, age, family planning, gender, and education status of people in certain areas.<ref name="MEA"/> Most of the exponential human population growth worldwide is occurring in or close to [[biodiversity hotspots]].<ref name="Cincotta"/> This may explain why human population density accounts for 87.9% of the variation in numbers of [[threatened species]] across 114 countries, providing indisputable evidence that people play the largest role in decreasing [[biodiversity]].<ref>McKee et al., 2003</ref> The boom in human population and migration of people into such species-rich regions are making [[conservation biology|conservation efforts]] not only more urgent but also more likely to conflict with local human interests.<ref name="Cincotta"/> The high local population density in such areas is directly correlated to the poverty status of the local people, most of whom lacking an education and family planning.<ref name="Geist">Geist & Lambin, 2002</ref>
From the Geist and Lambin (2002) study described in the previous section, the underlying driving forces were prioritized as follows (with the percent of the 152 cases the factor played a significant role in): economic factors (81%), institutional or policy factors (78%), technological factors (70%), cultural or socio-political factors (66%), and demographic factors (61%). The main economic factors included commercialization and growth of timber markets (68%), which are driven by national and international demands; urban industrial growth (38%); low domestic costs for land, labor, fuel, and timber (32%); and increases in product prices mainly for cash crops (25%). Institutional and policy factors included formal pro-deforestation policies on land development (40%), economic growth including colonization and infrastructure improvement (34%), and subsidies for land-based activities (26%); property rights and land-tenure insecurity (44%); and policy failures such as corruption, lawlessness, or mismanagement (42%). The main technological factor was the poor application of technology in the wood industry (45%), which leads to wasteful logging practices. Within the broad category of cultural and sociopolitical factors are public attitudes and values (63%), individual/household behavior (53%), public unconcern toward forest environments (43%), missing basic values (36%), and unconcern by individuals (32%). Demographic factors were the in-migration of colonizing settlers into sparsely populated forest areas (38%) and growing population density — a result of the first factor — in those areas (25%).
There are also feedbacks and interactions among the proximate and underlying causes of deforestation that can amplify the process. Road construction has the largest feedback effect, because it interacts with—and leads to—the establishment of new settlements and more people, which causes a growth in wood (logging) and food markets.<ref name="Geist"/> Growth in these markets, in turn, progresses the commercialization of agriculture and logging industries. When these industries become commercialized, they must become more efficient by utilizing larger or more modern machinery that often are worse on the habitat than traditional farming and logging methods. Either way, more land is cleared more rapidly for commercial markets. This common feedback example manifests just how closely related the proximate and underlying causes are to each other.
==Impact on human population==
[[File:KatrinaNewOrleansFlooded edit2.jpg|thumb|The draining and development of coastal wetlands that previously protected the Gulf Coast contributed to severe flooding in New Orleans, Louisiana in the aftermath of [[Hurricane Katrina]].<ref>Tibbetts, 2006</ref>]]
Habitat destruction vastly increases an area's vulnerability to [[natural disaster]]s like [[flood]] and [[drought]], [[crop failure]], [[spread of disease]], and [[water contamination]].<ref name="MEA"/> On the other hand, a healthy ecosystem with good management practices will reduce the chance of these events happening, or will at least mitigate adverse impacts.
Agricultural land can actually suffer from the destruction of the surrounding landscape. Over the past 50 years, the destruction of habitat surrounding agricultural land has degraded approximately 40% of agricultural land worldwide via [[erosion]], [[salinization]], [[Soil compaction|compaction]], [[Natural resource#Depletion|nutrient depletion]], [[pollution]], and [[urbanization]].<ref name="MEA"/> Humans also lose direct uses of natural habitat when habitat is destroyed. Aesthetic uses such as [[birdwatching]], recreational uses like [[hunting]] and [[fishing]], and [[ecotourism]] usually rely upon virtually undisturbed habitat. Many people value the complexity of the natural world and are disturbed by the loss of natural habitats and animal or plant species worldwide.
Probably the most profound impact that habitat destruction has on people is the loss of many valuable [[ecosystem services]]. Habitat destruction has altered nitrogen, phosphorus, sulfur, and [[carbon cycle]]s, which has increased the frequency and severity of [[acid rain]], [[algal bloom]]s, and [[fish kill]]s in rivers and oceans and contributed tremendously to global [[climate change]].<ref name="MEA"/> One ecosystem service whose significance is becoming more realized is [[Climate|climate regulation]]. On a local scale, trees provide windbreaks and shade; on a regional scale, [[Transpiration|plant transpiration]] recycles rainwater and maintains constant annual rainfall; on a global scale, plants (especially trees from tropical rainforests) from around the world counter the accumulation of [[greenhouse gas]]es in the atmosphere by [[Carbon dioxide sink|sequestering carbon dioxide]] through [[photosynthesis]].<ref name="Primack"/> Other ecosystem services that are diminished or lost altogether as a result of habitat destruction include [[watershed management]], [[nitrogen fixation]], oxygen production, [[pollination]] (see [[pollinator decline]]),<ref>{{cite journal|journal=PLoS One|volume=8|issue=5|year=2013|doi=10.1371/journal.pone.0063421|pmc=3661593|title=Plant Pollinator Networks along a Gradient of Urbanisation|author1=Benoît Geslin|author2=Benoit Gauzens|author3=Elisa Thébault|author4=Isabelle Dajoz}}</ref> [[waste treatment]] (i.e., the [[Decomposition|breaking down]] and immobilization of [[toxic]] pollutants), and [[Nutrient cycle|nutrient recycling]] of [[sewage]] or [[agricultural runoff]].<ref name="Primack"/>
The loss of trees from the tropical rainforests alone represents a substantial diminishing of the earth’s ability to produce oxygen and use up carbon dioxide. These services are becoming even more important as increasing [[carbon dioxide]] levels is one of the main contributors to global [[climate change]].
The [[Biodiversity loss|loss of biodiversity]] may not directly affect humans, but the indirect effects of losing many species as well as the diversity of ecosystems in general are enormous. When biodiversity is lost, the environment loses many species that provide valuable and unique roles to the ecosystem. The environment and all its inhabitants rely on biodiversity to recover from extreme environmental conditions. When too much biodiversity is lost, a catastrophic event such as an earthquake, flood, or volcanic eruption could cause an ecosystem to crash, and humans would obviously suffer from that. Loss of biodiversity also means that humans are losing animals that could have served as biological control agents and plants that could potentially provide higher-yielding crop varieties, pharmaceutical drugs to cure existing or future diseases or cancer, and new resistant crop varieties for agricultural species susceptible to pesticide-resistant insects or virulent strains of [[fungi]], [[virus]]es, and [[bacteria]].<ref name="Primack"/>
The negative effects of habitat destruction usually impact rural populations more directly than urban populations.<ref name="MEA"/> Across the globe, poor people suffer the most when natural habitat is destroyed, because less natural habitat means less natural resources per capita, yet wealthier people and countries simply have to pay more to continue to receive more than their per capita share of natural resources.
Another way to view the negative effects of habitat destruction is to look at the opportunity cost of keeping an area undisturbed. In other words, what are people losing out on by taking away a given habitat? A country may increase its food supply by converting forest land to row-crop agriculture, but the value of the same land may be much larger when it can supply natural resources or services such as clean water, timber, ecotourism, or flood regulation and drought control.<ref name="MEA"/>
==Outlook==
The [[Human overpopulation|rapid expansion of the global human population]] is increasing the world’s food requirement substantially. Simple logic instructs that more people will require more food. In fact, as the world’s population increases dramatically, agricultural output will need to increase by at least 50%, over the next 30 years.<ref name="Tilman">Tilman et al., 2001</ref> In the past, continually moving to new land and soils provided a boost in food production to appease the global food demand. That easy fix will no longer be available, however, as more than 98% of all land suitable for agriculture is already in use or degraded beyond repair.<ref>Sanderson et al., 2002</ref>
The impending global [[food crisis]] will be a major source of habitat destruction. Commercial farmers are going to become desperate to produce more food from the same amount of land, so they will use more [[fertilizer]]s and less concern for the environment to meet the market demand. Others will seek out new land or will convert other land-uses to agriculture. Agricultural intensification will become widespread at the cost of the environment and its inhabitants. Species will be pushed out of their habitat either directly by habitat destruction or indirectly by fragmentation, [[environmental degradation|degradation]], or [[pollution]]. Any efforts to protect the world’s remaining natural habitat and biodiversity will compete directly with humans’ growing demand for natural resources, especially new agricultural lands.<ref name="Tilman"/>
==Solutions==
[[File:Hawaii turtle.JPG|thumb|''[[Chelonia mydas]]'' on a Hawaiian coral reef. Although the endangered species is protected, habitat loss from human development is a major reason for the loss of [[green turtle]] nesting beaches.]]
In most cases of tropical deforestation, three to four underlying causes are driving two to three proximate causes.<ref name="Geist"/> This means that a universal policy for controlling tropical deforestation would not be able to address the unique combination of proximate and underlying causes of deforestation in each country.<ref name="Geist"/> Before any local, national, or international deforestation policies are written and enforced, governmental leaders must acquire a detailed understanding of the complex combination of proximate causes and underlying driving forces of deforestation in a given area or country.<ref name="Geist"/> This concept, along with many other results about tropical deforestation from the Geist and Lambin study, can easily be applied to habitat destruction in general. Governmental leaders need to take action by addressing the underlying driving forces, rather than merely regulating the proximate causes. In a broader sense, governmental bodies at a local, national, and international scale need to emphasize the following:
#Considering the many irreplaceable ecosystem services provided by natural habitats.
#Protecting remaining intact sections of natural habitat.
#Educating the public about the importance of natural habitat and biodiversity.
#Developing [[family planning]] programs in areas of rapid population growth.
#Finding ecological ways to increase agricultural output without increasing the total land in production.
#Preserving habitat corridors to minimize prior damage from fragmented habitats.
#Reduce [[human population]] and expansion.
==Notes==
{{reflist|2}}
==References==
{{refbegin|2}}
*Barbault, R. and S. D. Sastrapradja. 1995. Generation, maintenance and loss of biodiversity. Global Biodiversity Assessment, Cambridge Univ. Press, Cambridge pp. 193–274.
*Burke, L., Y. Kura, K. Kassem, C. Ravenga, M. Spalding, and D. McAllister. 2000. Pilot Assessment of Global Ecosystems: Coastal Ecosystems. World Resources Institute, Washington, D.C.
*Cincotta, R.P., and R. Engelman. 2000. Nature's place: human population density and the future of biological diversity. Population Action International. Washington, D.C.
*{{cite journal |author1=Geist H. J. |author2=Lambin E. E. | year = 2002 | title = Proximate causes and underlying driving forces of tropical deforestation | url = | journal = BioScience | volume = 52 | issue = 2| pages = 143–150 | doi=10.1641/0006-3568(2002)052[0143:PCAUDF]2.0.CO;2}}
*Kauffman, J. B. and D. A. Pyke. 2001. Range ecology, global livestock influences. In S. A. Levin (ed.), Encyclopedia of Biodiversity 5: 33-52. Academic Press, San Diego, CA.
*{{cite journal | author = Laurance W. F. | year = 1999 | title = Reflections on the tropical deforestation crisis | url = | journal = Biological Conservation | volume = 91 | issue = | pages = 109–117 | doi=10.1016/S0006-3207(99)00088-9}}
*{{cite journal |author1=McKee J. K. |author2=Sciulli P.W. |author3=Fooce C. D. |author4=Waite T. A. | year = 2003 | title = Forecasting global biodiversity threats associated with human population growth | url = | journal = Biological Conservation | volume = 115 | issue = | pages = 161–164 | doi=10.1016/s0006-3207(03)00099-5}}
*Millennium Ecosystem Assessment (Program). 2005. [https://books.google.com/books?id=UFVmiSAr-okC&dq=Ecosystems+and+Human+Well-Being Ecosystems and Human Well-Being]. Millennium Ecosystem Assessment. Island Press, Covelo, CA.
*Primack, R. B. 2006. Essentials of Conservation Biology. 4th Ed. Habitat destruction, pages 177-188. Sinauer Associates, Sunderland, MA.
*{{cite journal |author1=Pimm Stuart L. |author2=Raven Peter | year = 2000 | title = Biodiversity: Extinction by numbers | url = | journal = Nature | volume = 403 | issue = 6772| pages = 843–845 | doi = 10.1038/35002708 | pmid=10706267}}
*Ravenga, C., J. Brunner, N. Henninger, K. Kassem, and R. Payne. 2000. Pilot Analysis of Global Ecosystems: Wetland Ecosystems. World Resources Institute, Washington, D.C.
*{{cite journal |author1=Sahney S. |author2=Benton M.J. |author3=Falcon-Lang H.J. | year = 2010 | title = Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euramerica | url = | journal = Geology | volume = 38 | issue = | pages = 1079–1082 | doi=10.1130/G31182.1}}
*{{cite journal |author1=Sanderson E. W. |author2=Jaiteh M. |author3=Levy M. A. |author4=Redford K. H. |author5=Wannebo A. V. |author6=Woolmer G. | year = 2002 | title = The human footprint and the last of the wild | url = | journal = BioScience | volume = 52 | issue = 10| pages = 891–904 | doi=10.1641/0006-3568(2002)052[0891:thfatl]2.0.co;2}}
*Scholes, R. J. and R. Biggs (eds.). 2004. Ecosystem services in Southern Africa: a regional assessment. The regional scale component of the Southern African Millennium Ecosystem Assessment. CSIR, Pretoria, South Africa.
*Stein, B. A., L. S. Kutner, and J. S. Adams (eds.). 2000. Precious Heritage: The Status of Biodiversity in the United States. Oxford University Press, New York.
*{{cite journal | author = Temple S. A. | year = 1986 | title = The problem of avian extinctions | url = | journal = Ornithology | volume = 3 | issue = | pages = 453–485 | doi=10.1007/978-1-4615-6784-4_11}}
*{{cite journal | author = Tibbetts John | year = 2006 | title = Louisiana's Wetlands: A Lesson in Nature Appreciation | pmc = 1332684 | journal = Environ Health Perspect | volume = 114 | issue = 1| pages = A40–A43 | pmid=16393646 | doi=10.1289/ehp.114-a40}}
*{{cite journal |author1=Tilman D. |author2=Fargione J. |author3=Wolff B. |author4=D'Antonio C. |author5=Dobson A. |author6=Howarth R. |author7=Schindler D. |author8=Schlesinger W. H. |author9=Simberloff D. | year = 2001 | title = Forecasting agriculturally driven global environmental change | url = | journal = Science | volume = 292 | issue = | pages = 281–284 | doi=10.1126/science.1057544 | pmid=11303102|display-authors=etal}}
*White, R. P., S. Murray, and M. Rohweder. 2000. Pilot Assessment of Global Ecosystems: Grassland Ecosystems. World Resources Institute, Washington, D. C.
*WRI. 2003. World Resources 2002-2004: Decisions for the Earth: Balance, voice, and power. 328 pp. World Resources Institute, Washington, D.C.
{{refend}}
{{Extinction}}
{{human impact on the environment|state=expanded}}
{{threatened species}}
{{population}}
[[Category:Habitats| ]]
[[Category:Habitat]]
[[Category:Environmental conservation]]
[[Category:Environmental terminology]]
[[Category:Environmental impact by effect]]
[[fr:Perturbation écologique]]' |
Unified diff of changes made by edit (edit_diff ) | '@@ -1,128 +1,1 @@
-'''Habitat destruction''' is the process in which natural [[habitat]] is rendered unable to support the species present. In this process, the organisms that previously used the site are displaced or destroyed, reducing [[biodiversity]].<ref name="SahneyBentonFerry2010LinksDiversityVertebrates">{{ cite journal | url=http://geology.geoscienceworld.org/cgi/content/abstract/38/12/1079 | author= Sahney, S., Benton, M.J. & Falcon-Lang, H.J. | year=2010 | title= Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euram eri ca | journal=Geology | volume = 38 | pages = 1079–1082 | format=PDF | doi=10.1130/G31182.1 | issue=12}}</ref> Habitat destruction by human activity is mainly for the purpose of harvesting [[natural resources]] for industry 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.<ref>Pimm & Raven, 2000, pp. 843-845</ref> It is a process of natural environmental change that may be caused by [[habitat fragmentation]], geological processes, [[climate change]]<ref name="SahneyBentonFerry2010LinksDiversityVertebrates"/> or by human activities such as the introduction of [[invasive species]], ecosystem nutrient depletion, and other human activities.
-
-The terms '''habitat loss''' and '''habitat reduction''' are also used in a wider sense, including loss of habitat from other factors, such as [[water pollution|water]] and [[noise pollution]].
-
-==Impacts on organisms==
-In the simplest term, when a habitat is destroyed, the plants, animals, and other organisms that occupied the habitat have a reduced [[carrying capacity]] so that populations decline and [[extinction]] becomes more likely.<ref>Scholes & Biggs, 2004</ref> Perhaps the greatest threat to organisms and biodiversity is the process of habitat loss.<ref>Barbault & Sastrapradja, 1995</ref> Temple (1986) found that 82% of [[Endangered species|endangered bird species]] were significantly threatened by habitat loss. Most amphibian species are also threatened by habitat loss<ref>{{cite journal|last1=Beebee|first1=Trevor J.C.|last2=Griffiths|first2=Richard A.|title=The amphibian decline crisis: A watershed for conservation biology?|journal=Biological Conservation|date=31 May 2005|volume=125|issue=3|page=271|doi=10.1016/j.biocon.2005.04.009|url=http://www.sciencedirect.com/science/article/pii/S0006320705001825}}</ref>, and some species are now only breeding in modified habitat<ref>{{cite journal|last1=Borzée|first1=Amaël|last2=Jang|first2=Yikweon|title=Description of a seminatural habitat of the endangered Suweon treefrog Hyla suweonensis|journal=Animal Cells and Systems|date=28 April 2015|volume=19|issue=3|page=216|doi=10.1080/19768354.2015.1028442|url=http://www.tandfonline.com/doi/abs/10.1080/19768354.2015.1028442}}</ref>. [[endemism|Endemic]] organisms with limited ranges are most affected by habitat destruction, mainly because these organisms are not found anywhere else within the world and thus, have less chance of recovering. Many endemic organisms have very specific requirements for their survival that can only be found within a certain ecosystem, resulting in their extinction. Extinction may also take place very long after the destruction of habitat, a phenomenon known as [[extinction debt]]. Habitat destruction can also decrease the range of certain organism populations. This can result in the reduction of genetic diversity and perhaps the production of [[infertile]] youths, as these organisms would have a higher possibility of mating with related organisms within their population, or different species. One of the most famous examples is the impact upon China's [[giant panda]], once found across the nation. Now it is only found in fragmented and isolated regions in the southwest of the country, as a result of widespread [[deforestation]] in the 20th century.<ref>[http://pulitzercenter.org/reporting/china-sichuan-panda-deforestation-habitat-mountain-conservation The Panda's Forest: Biodiversity Loss]</ref>
-
-==Geography==
-[[File:Bolivia-Deforestation-EO.JPG|thumb|right|Satellite photograph of deforestation in Bolivia. Originally dry tropical forest, the land is being cleared for [[soybean]] cultivation.<ref>{{cite web
- | title = Tierras Bajas Deforestation, Bolivia
- | work = Newsroom. Photo taken from the International Space Station on April 16, 2001
- | publisher = [[NASA Earth Observatory]]
- | date = 2001-04-16
- | url = http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=4842
- | accessdate = 2008-08-11
-}}</ref>]]
-[[Biodiversity hotspot]]s are chiefly [[tropical]] regions that feature high concentrations of [[Endemism|endemic]] species and, when all hotspots are combined, may contain over half of the world’s [[Terrestrial animal|terrestrial]] species.<ref name="Cincotta">Cincotta & Engelman, 2000</ref> These hotspots are suffering from habitat loss and destruction.
-Most of the natural habitat on islands and in areas of high human population density has already been destroyed (WRI, 2003). Islands suffering extreme habitat destruction include [[New Zealand]], [[Madagascar]], the [[Philippines]], and [[Japan]].<ref name="Primack">Primack, 2006</ref> South and East Asia — especially [[China]], [[India]], [[Malaysia]], [[Indonesia]], and Japan — and many areas in [[West Africa]] have extremely dense human populations that allow little room for natural habitat. Marine areas close to highly populated [[coast]]al cities also face degradation of their [[coral reef]]s or other marine habitat. These areas include the eastern coasts of Asia and Africa, northern coasts of [[South America]], and the [[Caribbean Sea]] and its associated [[island]]s.<ref name="Primack"/>
-
-Regions of un[[sustainable agriculture]] or unstable governments, which may go hand-in-hand, typically experience high rates of habitat destruction. [[Central America]], [[Sub-Saharan Africa]], and the [[Amazonian tropical rainforest]] areas of [[South America]] are the main regions with unsustainable agricultural practices and/or government mismanagement.<ref name="Primack"/>
-
-Areas of high agricultural output tend to have the highest extent of habitat destruction. In the U.S., less than 25% of native vegetation remains in many parts of the [[Eastern United States|East]] and [[Midwestern United States|Midwest]].<ref name="Stein">Stein et al., 2000</ref> Only 15% of land area remains unmodified by human activities in all of Europe.<ref name="Primack"/>
-
-==Ecosystems==
-[[File:Lacanja burn.JPG|thumb|Jungle burned for agriculture in southern Mexico]]
-[[Tropical rainforest]]s have received most of the attention concerning the destruction of habitat. From the approximately 16 million square kilometers of tropical rainforest habitat that originally existed worldwide, less than 9 million square kilometers remain today.<ref name="Primack"/> The current rate of [[deforestation]] is 160,000 square kilometers per year, which equates to a loss of approximately 1% of original forest habitat each year.<ref name="Laurance">Laurance, 1999</ref>
-
-Other forest [[ecosystem]]s have suffered as much or more destruction as tropical [[rainforest]]s. [[Farming]] and [[logging]] have severely disturbed at least 94% of [[Temperate broadleaf and mixed forests|temperate broadleaf forests]]; many [[old growth forest]] stands have lost more than 98% of their previous area because of human activities.<ref name="Primack"/> [[Tropical and subtropical dry broadleaf forests|Tropical deciduous dry forests]] are easier to [[Slash and burn|clear and burn]] and are more suitable for agriculture and [[cattle ranching]] than tropical rainforests; consequently, less than 0.1% of [[Tropical and subtropical dry broadleaf forests|dry forests in Central America's Pacific Coast]] and less than 8% in [[Madagascar dry deciduous forests|Madagascar]] remain from their original extents.<ref name="Laurance"/>
-
-[[File:Farmland-batang bungo.jpg|thumb|left|Farmers near newly cleared land within Taman Nasional Kerinci Seblat ([[Kerinci Seblat National Park]]), [[Sumatra]].]]
-Plains and [[desert]] areas have been degraded to a lesser extent. Only 10-20% of the world's [[drylands]], which include [[temperate grasslands, savannas, and shrublands]], [[Scrubland|scrub]], and [[Temperate deciduous forest|deciduous forests]], have been somewhat degraded.<ref>Kauffman & Pyke, 2001</ref> But included in that 10-20% of land is the approximately 9 million square kilometers of seasonally dry-lands that humans have converted to deserts through the process of desertification.<ref name="Primack"/> The [[tallgrass prairie]]s of North America, on the other hand, have less than 3% of natural habitat remaining that has not been converted to farmland.<ref>White et al., 2000</ref>
-
-[[Wetland]]s and marine areas have endured high levels of habitat destruction. More than 50% of wetlands in the U.S. have been destroyed in just the last 200 years.<ref name="Stein"/> Between 60% and 70% of European wetlands have been completely destroyed.<ref>Ravenga et al., 2000</ref> About one-fifth (20%) of marine coastal areas have been highly modified by humans.<ref>Burke et al., 2000</ref> One-fifth of coral reefs have also been destroyed, and another fifth has been severely degraded by [[overfishing]], pollution, and [[invasive species]]; 90% of the Philippines’ coral reefs alone have been destroyed.<ref name="MEA">MEA, 2005</ref> Finally, over 35% [[Coastal ecosystems|mangrove ecosystems]] worldwide have been destroyed.<ref name="MEA"/>
-{{clear}}
-
-==Natural causes==
-Habitat destruction through natural processes such as volcanism, [[fire]], and climate change is well documented in the fossil record.<ref name="SahneyBentonFerry2010LinksDiversityVertebrates"/> One study shows that habitat fragmentation of tropical rainforests in Euramerica 300 million years ago led to a great loss of amphibian diversity, but simultaneously the drier climate spurred on a burst of diversity among reptiles.<ref name="SahneyBentonFerry2010LinksDiversityVertebrates"/>
-
-==Human causes==
-[[File:Amazonie deforestation.jpg|thumb|Deforestation and roads in Amazonia, the [[Amazon Rainforest]].]]
-
-Habitat destruction caused by humans includes [[land conversion]] from forests, etc. to [[arable land]], [[urban sprawl]], [[Public works|infrastructure development]], and other anthropogenic changes to the characteristics of land. Habitat degradation, fragmentation, and [[pollution]] are aspects of habitat destruction caused by humans that do not necessarily involve over destruction of habitat, yet result in habitat collapse. [[Desertification]], [[deforestation]], and [[Coral bleaching|coral reef degradation]] are specific types of habitat destruction for those areas ([[desert]]s, [[forest]]s, [[coral reef]]s).
-
-Geist and Lambin (2002) assessed 152 case studies of net losses of tropical forest cover to determine any patterns in the proximate and underlying causes of tropical deforestation. Their results, yielded as percentages of the case studies in which each parameter was a significant factor, provide a quantitative prioritization of which proximate and underlying causes were the most significant. The proximate causes were clustered into broad categories of [[agricultural expansion]] (96%), [[infrastructure expansion]] (72%), and [[wood extraction]] (67%). Therefore, according to this study, [[forest conversion]] to agriculture is the main land use change responsible for tropical deforestation. The specific categories reveal further insight into the specific causes of tropical deforestation: transport extension (64%), commercial wood extraction (52%), [[permanent cultivation]] (48%), [[cattle ranching]] (46%), shifting ([[slash and burn]]) cultivation (41%), [[subsistence agriculture]] (40%), and [[fuel wood]] extraction for domestic use (28%). One result is that [[shifting cultivation]] is not the primary cause of deforestation in all world regions, while transport extension (including the [[Road construction|construction of new roads]]) is the largest single proximate factor responsible for deforestation.<ref name="Geist"/>
-
-==Drivers==
-[[File:Crowded Nanjing Road in Shanghai.jpeg|thumb|Nanjing Road in Shanghai]]
-While the above-mentioned activities are the proximal or direct causes of habitat destruction in that they actually destroy habitat, this still does not identify why humans destroy habitat. The forces that cause humans to destroy habitat are known as ''drivers'' of habitat destruction. [[Demographic]], economic, sociopolitical, scientific and technological, and cultural drivers all contribute to habitat destruction.<ref name="MEA"/>
-
-Demographic drivers include the [[Human overpopulation|expanding human population]]; rate of [[Population growth|population increase]] over time; [[Population density|spatial distribution]] of people in a given area ([[List of urban areas by population|urban]] versus rural), ecosystem type, and country; and the combined effects of poverty, age, family planning, gender, and education status of people in certain areas.<ref name="MEA"/> Most of the exponential human population growth worldwide is occurring in or close to [[biodiversity hotspots]].<ref name="Cincotta"/> This may explain why human population density accounts for 87.9% of the variation in numbers of [[threatened species]] across 114 countries, providing indisputable evidence that people play the largest role in decreasing [[biodiversity]].<ref>McKee et al., 2003</ref> The boom in human population and migration of people into such species-rich regions are making [[conservation biology|conservation efforts]] not only more urgent but also more likely to conflict with local human interests.<ref name="Cincotta"/> The high local population density in such areas is directly correlated to the poverty status of the local people, most of whom lacking an education and family planning.<ref name="Geist">Geist & Lambin, 2002</ref>
-
-From the Geist and Lambin (2002) study described in the previous section, the underlying driving forces were prioritized as follows (with the percent of the 152 cases the factor played a significant role in): economic factors (81%), institutional or policy factors (78%), technological factors (70%), cultural or socio-political factors (66%), and demographic factors (61%). The main economic factors included commercialization and growth of timber markets (68%), which are driven by national and international demands; urban industrial growth (38%); low domestic costs for land, labor, fuel, and timber (32%); and increases in product prices mainly for cash crops (25%). Institutional and policy factors included formal pro-deforestation policies on land development (40%), economic growth including colonization and infrastructure improvement (34%), and subsidies for land-based activities (26%); property rights and land-tenure insecurity (44%); and policy failures such as corruption, lawlessness, or mismanagement (42%). The main technological factor was the poor application of technology in the wood industry (45%), which leads to wasteful logging practices. Within the broad category of cultural and sociopolitical factors are public attitudes and values (63%), individual/household behavior (53%), public unconcern toward forest environments (43%), missing basic values (36%), and unconcern by individuals (32%). Demographic factors were the in-migration of colonizing settlers into sparsely populated forest areas (38%) and growing population density — a result of the first factor — in those areas (25%).
-
-There are also feedbacks and interactions among the proximate and underlying causes of deforestation that can amplify the process. Road construction has the largest feedback effect, because it interacts with—and leads to—the establishment of new settlements and more people, which causes a growth in wood (logging) and food markets.<ref name="Geist"/> Growth in these markets, in turn, progresses the commercialization of agriculture and logging industries. When these industries become commercialized, they must become more efficient by utilizing larger or more modern machinery that often are worse on the habitat than traditional farming and logging methods. Either way, more land is cleared more rapidly for commercial markets. This common feedback example manifests just how closely related the proximate and underlying causes are to each other.
-
-==Impact on human population==
-[[File:KatrinaNewOrleansFlooded edit2.jpg|thumb|The draining and development of coastal wetlands that previously protected the Gulf Coast contributed to severe flooding in New Orleans, Louisiana in the aftermath of [[Hurricane Katrina]].<ref>Tibbetts, 2006</ref>]]
-Habitat destruction vastly increases an area's vulnerability to [[natural disaster]]s like [[flood]] and [[drought]], [[crop failure]], [[spread of disease]], and [[water contamination]].<ref name="MEA"/> On the other hand, a healthy ecosystem with good management practices will reduce the chance of these events happening, or will at least mitigate adverse impacts.
-
-Agricultural land can actually suffer from the destruction of the surrounding landscape. Over the past 50 years, the destruction of habitat surrounding agricultural land has degraded approximately 40% of agricultural land worldwide via [[erosion]], [[salinization]], [[Soil compaction|compaction]], [[Natural resource#Depletion|nutrient depletion]], [[pollution]], and [[urbanization]].<ref name="MEA"/> Humans also lose direct uses of natural habitat when habitat is destroyed. Aesthetic uses such as [[birdwatching]], recreational uses like [[hunting]] and [[fishing]], and [[ecotourism]] usually rely upon virtually undisturbed habitat. Many people value the complexity of the natural world and are disturbed by the loss of natural habitats and animal or plant species worldwide.
-
-Probably the most profound impact that habitat destruction has on people is the loss of many valuable [[ecosystem services]]. Habitat destruction has altered nitrogen, phosphorus, sulfur, and [[carbon cycle]]s, which has increased the frequency and severity of [[acid rain]], [[algal bloom]]s, and [[fish kill]]s in rivers and oceans and contributed tremendously to global [[climate change]].<ref name="MEA"/> One ecosystem service whose significance is becoming more realized is [[Climate|climate regulation]]. On a local scale, trees provide windbreaks and shade; on a regional scale, [[Transpiration|plant transpiration]] recycles rainwater and maintains constant annual rainfall; on a global scale, plants (especially trees from tropical rainforests) from around the world counter the accumulation of [[greenhouse gas]]es in the atmosphere by [[Carbon dioxide sink|sequestering carbon dioxide]] through [[photosynthesis]].<ref name="Primack"/> Other ecosystem services that are diminished or lost altogether as a result of habitat destruction include [[watershed management]], [[nitrogen fixation]], oxygen production, [[pollination]] (see [[pollinator decline]]),<ref>{{cite journal|journal=PLoS One|volume=8|issue=5|year=2013|doi=10.1371/journal.pone.0063421|pmc=3661593|title=Plant Pollinator Networks along a Gradient of Urbanisation|author1=Benoît Geslin|author2=Benoit Gauzens|author3=Elisa Thébault|author4=Isabelle Dajoz}}</ref> [[waste treatment]] (i.e., the [[Decomposition|breaking down]] and immobilization of [[toxic]] pollutants), and [[Nutrient cycle|nutrient recycling]] of [[sewage]] or [[agricultural runoff]].<ref name="Primack"/>
-
-The loss of trees from the tropical rainforests alone represents a substantial diminishing of the earth’s ability to produce oxygen and use up carbon dioxide. These services are becoming even more important as increasing [[carbon dioxide]] levels is one of the main contributors to global [[climate change]].
-
-The [[Biodiversity loss|loss of biodiversity]] may not directly affect humans, but the indirect effects of losing many species as well as the diversity of ecosystems in general are enormous. When biodiversity is lost, the environment loses many species that provide valuable and unique roles to the ecosystem. The environment and all its inhabitants rely on biodiversity to recover from extreme environmental conditions. When too much biodiversity is lost, a catastrophic event such as an earthquake, flood, or volcanic eruption could cause an ecosystem to crash, and humans would obviously suffer from that. Loss of biodiversity also means that humans are losing animals that could have served as biological control agents and plants that could potentially provide higher-yielding crop varieties, pharmaceutical drugs to cure existing or future diseases or cancer, and new resistant crop varieties for agricultural species susceptible to pesticide-resistant insects or virulent strains of [[fungi]], [[virus]]es, and [[bacteria]].<ref name="Primack"/>
-
-The negative effects of habitat destruction usually impact rural populations more directly than urban populations.<ref name="MEA"/> Across the globe, poor people suffer the most when natural habitat is destroyed, because less natural habitat means less natural resources per capita, yet wealthier people and countries simply have to pay more to continue to receive more than their per capita share of natural resources.
-
-Another way to view the negative effects of habitat destruction is to look at the opportunity cost of keeping an area undisturbed. In other words, what are people losing out on by taking away a given habitat? A country may increase its food supply by converting forest land to row-crop agriculture, but the value of the same land may be much larger when it can supply natural resources or services such as clean water, timber, ecotourism, or flood regulation and drought control.<ref name="MEA"/>
-
-==Outlook==
-The [[Human overpopulation|rapid expansion of the global human population]] is increasing the world’s food requirement substantially. Simple logic instructs that more people will require more food. In fact, as the world’s population increases dramatically, agricultural output will need to increase by at least 50%, over the next 30 years.<ref name="Tilman">Tilman et al., 2001</ref> In the past, continually moving to new land and soils provided a boost in food production to appease the global food demand. That easy fix will no longer be available, however, as more than 98% of all land suitable for agriculture is already in use or degraded beyond repair.<ref>Sanderson et al., 2002</ref>
-
-The impending global [[food crisis]] will be a major source of habitat destruction. Commercial farmers are going to become desperate to produce more food from the same amount of land, so they will use more [[fertilizer]]s and less concern for the environment to meet the market demand. Others will seek out new land or will convert other land-uses to agriculture. Agricultural intensification will become widespread at the cost of the environment and its inhabitants. Species will be pushed out of their habitat either directly by habitat destruction or indirectly by fragmentation, [[environmental degradation|degradation]], or [[pollution]]. Any efforts to protect the world’s remaining natural habitat and biodiversity will compete directly with humans’ growing demand for natural resources, especially new agricultural lands.<ref name="Tilman"/>
-
-==Solutions==
-[[File:Hawaii turtle.JPG|thumb|''[[Chelonia mydas]]'' on a Hawaiian coral reef. Although the endangered species is protected, habitat loss from human development is a major reason for the loss of [[green turtle]] nesting beaches.]]
-In most cases of tropical deforestation, three to four underlying causes are driving two to three proximate causes.<ref name="Geist"/> This means that a universal policy for controlling tropical deforestation would not be able to address the unique combination of proximate and underlying causes of deforestation in each country.<ref name="Geist"/> Before any local, national, or international deforestation policies are written and enforced, governmental leaders must acquire a detailed understanding of the complex combination of proximate causes and underlying driving forces of deforestation in a given area or country.<ref name="Geist"/> This concept, along with many other results about tropical deforestation from the Geist and Lambin study, can easily be applied to habitat destruction in general. Governmental leaders need to take action by addressing the underlying driving forces, rather than merely regulating the proximate causes. In a broader sense, governmental bodies at a local, national, and international scale need to emphasize the following:
-
-#Considering the many irreplaceable ecosystem services provided by natural habitats.
-#Protecting remaining intact sections of natural habitat.
-#Educating the public about the importance of natural habitat and biodiversity.
-#Developing [[family planning]] programs in areas of rapid population growth.
-#Finding ecological ways to increase agricultural output without increasing the total land in production.
-#Preserving habitat corridors to minimize prior damage from fragmented habitats.
-#Reduce [[human population]] and expansion.
-
-==Notes==
-{{reflist|2}}
-
-==References==
-{{refbegin|2}}
-*Barbault, R. and S. D. Sastrapradja. 1995. Generation, maintenance and loss of biodiversity. Global Biodiversity Assessment, Cambridge Univ. Press, Cambridge pp. 193–274.
-*Burke, L., Y. Kura, K. Kassem, C. Ravenga, M. Spalding, and D. McAllister. 2000. Pilot Assessment of Global Ecosystems: Coastal Ecosystems. World Resources Institute, Washington, D.C.
-*Cincotta, R.P., and R. Engelman. 2000. Nature's place: human population density and the future of biological diversity. Population Action International. Washington, D.C.
-*{{cite journal |author1=Geist H. J. |author2=Lambin E. E. | year = 2002 | title = Proximate causes and underlying driving forces of tropical deforestation | url = | journal = BioScience | volume = 52 | issue = 2| pages = 143–150 | doi=10.1641/0006-3568(2002)052[0143:PCAUDF]2.0.CO;2}}
-*Kauffman, J. B. and D. A. Pyke. 2001. Range ecology, global livestock influences. In S. A. Levin (ed.), Encyclopedia of Biodiversity 5: 33-52. Academic Press, San Diego, CA.
-*{{cite journal | author = Laurance W. F. | year = 1999 | title = Reflections on the tropical deforestation crisis | url = | journal = Biological Conservation | volume = 91 | issue = | pages = 109–117 | doi=10.1016/S0006-3207(99)00088-9}}
-*{{cite journal |author1=McKee J. K. |author2=Sciulli P.W. |author3=Fooce C. D. |author4=Waite T. A. | year = 2003 | title = Forecasting global biodiversity threats associated with human population growth | url = | journal = Biological Conservation | volume = 115 | issue = | pages = 161–164 | doi=10.1016/s0006-3207(03)00099-5}}
-*Millennium Ecosystem Assessment (Program). 2005. [https://books.google.com/books?id=UFVmiSAr-okC&dq=Ecosystems+and+Human+Well-Being Ecosystems and Human Well-Being]. Millennium Ecosystem Assessment. Island Press, Covelo, CA.
-*Primack, R. B. 2006. Essentials of Conservation Biology. 4th Ed. Habitat destruction, pages 177-188. Sinauer Associates, Sunderland, MA.
-*{{cite journal |author1=Pimm Stuart L. |author2=Raven Peter | year = 2000 | title = Biodiversity: Extinction by numbers | url = | journal = Nature | volume = 403 | issue = 6772| pages = 843–845 | doi = 10.1038/35002708 | pmid=10706267}}
-*Ravenga, C., J. Brunner, N. Henninger, K. Kassem, and R. Payne. 2000. Pilot Analysis of Global Ecosystems: Wetland Ecosystems. World Resources Institute, Washington, D.C.
-*{{cite journal |author1=Sahney S. |author2=Benton M.J. |author3=Falcon-Lang H.J. | year = 2010 | title = Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euramerica | url = | journal = Geology | volume = 38 | issue = | pages = 1079–1082 | doi=10.1130/G31182.1}}
-*{{cite journal |author1=Sanderson E. W. |author2=Jaiteh M. |author3=Levy M. A. |author4=Redford K. H. |author5=Wannebo A. V. |author6=Woolmer G. | year = 2002 | title = The human footprint and the last of the wild | url = | journal = BioScience | volume = 52 | issue = 10| pages = 891–904 | doi=10.1641/0006-3568(2002)052[0891:thfatl]2.0.co;2}}
-*Scholes, R. J. and R. Biggs (eds.). 2004. Ecosystem services in Southern Africa: a regional assessment. The regional scale component of the Southern African Millennium Ecosystem Assessment. CSIR, Pretoria, South Africa.
-*Stein, B. A., L. S. Kutner, and J. S. Adams (eds.). 2000. Precious Heritage: The Status of Biodiversity in the United States. Oxford University Press, New York.
-*{{cite journal | author = Temple S. A. | year = 1986 | title = The problem of avian extinctions | url = | journal = Ornithology | volume = 3 | issue = | pages = 453–485 | doi=10.1007/978-1-4615-6784-4_11}}
-*{{cite journal | author = Tibbetts John | year = 2006 | title = Louisiana's Wetlands: A Lesson in Nature Appreciation | pmc = 1332684 | journal = Environ Health Perspect | volume = 114 | issue = 1| pages = A40–A43 | pmid=16393646 | doi=10.1289/ehp.114-a40}}
-*{{cite journal |author1=Tilman D. |author2=Fargione J. |author3=Wolff B. |author4=D'Antonio C. |author5=Dobson A. |author6=Howarth R. |author7=Schindler D. |author8=Schlesinger W. H. |author9=Simberloff D. | year = 2001 | title = Forecasting agriculturally driven global environmental change | url = | journal = Science | volume = 292 | issue = | pages = 281–284 | doi=10.1126/science.1057544 | pmid=11303102|display-authors=etal}}
-*White, R. P., S. Murray, and M. Rohweder. 2000. Pilot Assessment of Global Ecosystems: Grassland Ecosystems. World Resources Institute, Washington, D. C.
-*WRI. 2003. World Resources 2002-2004: Decisions for the Earth: Balance, voice, and power. 328 pp. World Resources Institute, Washington, D.C.
-
-{{refend}}
-
-{{Extinction}}
-{{human impact on the environment|state=expanded}}
-{{threatened species}}
-{{population}}
-
-[[Category:Habitats| ]]
-[[Category:Habitat]]
-[[Category:Environmental conservation]]
-[[Category:Environmental terminology]]
-[[Category:Environmental impact by effect]]
-
-[[fr:Perturbation écologique]]
+pornhub.com is why this happends
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0 => ''''Habitat destruction''' is the process in which natural [[habitat]] is rendered unable to support the species present. In this process, the organisms that previously used the site are displaced or destroyed, reducing [[biodiversity]].<ref name="SahneyBentonFerry2010LinksDiversityVertebrates">{{ cite journal | url=http://geology.geoscienceworld.org/cgi/content/abstract/38/12/1079 | author= Sahney, S., Benton, M.J. & Falcon-Lang, H.J. | year=2010 | title= Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euram eri ca | journal=Geology | volume = 38 | pages = 1079–1082 | format=PDF | doi=10.1130/G31182.1 | issue=12}}</ref> Habitat destruction by human activity is mainly for the purpose of harvesting [[natural resources]] for industry 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.<ref>Pimm & Raven, 2000, pp. 843-845</ref> It is a process of natural environmental change that may be caused by [[habitat fragmentation]], geological processes, [[climate change]]<ref name="SahneyBentonFerry2010LinksDiversityVertebrates"/> or by human activities such as the introduction of [[invasive species]], ecosystem nutrient depletion, and other human activities.',
1 => false,
2 => 'The terms '''habitat loss''' and '''habitat reduction''' are also used in a wider sense, including loss of habitat from other factors, such as [[water pollution|water]] and [[noise pollution]].',
3 => false,
4 => '==Impacts on organisms==',
5 => 'In the simplest term, when a habitat is destroyed, the plants, animals, and other organisms that occupied the habitat have a reduced [[carrying capacity]] so that populations decline and [[extinction]] becomes more likely.<ref>Scholes & Biggs, 2004</ref> Perhaps the greatest threat to organisms and biodiversity is the process of habitat loss.<ref>Barbault & Sastrapradja, 1995</ref> Temple (1986) found that 82% of [[Endangered species|endangered bird species]] were significantly threatened by habitat loss. Most amphibian species are also threatened by habitat loss<ref>{{cite journal|last1=Beebee|first1=Trevor J.C.|last2=Griffiths|first2=Richard A.|title=The amphibian decline crisis: A watershed for conservation biology?|journal=Biological Conservation|date=31 May 2005|volume=125|issue=3|page=271|doi=10.1016/j.biocon.2005.04.009|url=http://www.sciencedirect.com/science/article/pii/S0006320705001825}}</ref>, and some species are now only breeding in modified habitat<ref>{{cite journal|last1=Borzée|first1=Amaël|last2=Jang|first2=Yikweon|title=Description of a seminatural habitat of the endangered Suweon treefrog Hyla suweonensis|journal=Animal Cells and Systems|date=28 April 2015|volume=19|issue=3|page=216|doi=10.1080/19768354.2015.1028442|url=http://www.tandfonline.com/doi/abs/10.1080/19768354.2015.1028442}}</ref>. [[endemism|Endemic]] organisms with limited ranges are most affected by habitat destruction, mainly because these organisms are not found anywhere else within the world and thus, have less chance of recovering. Many endemic organisms have very specific requirements for their survival that can only be found within a certain ecosystem, resulting in their extinction. Extinction may also take place very long after the destruction of habitat, a phenomenon known as [[extinction debt]]. Habitat destruction can also decrease the range of certain organism populations. This can result in the reduction of genetic diversity and perhaps the production of [[infertile]] youths, as these organisms would have a higher possibility of mating with related organisms within their population, or different species. One of the most famous examples is the impact upon China's [[giant panda]], once found across the nation. Now it is only found in fragmented and isolated regions in the southwest of the country, as a result of widespread [[deforestation]] in the 20th century.<ref>[http://pulitzercenter.org/reporting/china-sichuan-panda-deforestation-habitat-mountain-conservation The Panda's Forest: Biodiversity Loss]</ref>',
6 => false,
7 => '==Geography==',
8 => '[[File:Bolivia-Deforestation-EO.JPG|thumb|right|Satellite photograph of deforestation in Bolivia. Originally dry tropical forest, the land is being cleared for [[soybean]] cultivation.<ref>{{cite web',
9 => ' | title = Tierras Bajas Deforestation, Bolivia',
10 => ' | work = Newsroom. Photo taken from the International Space Station on April 16, 2001',
11 => ' | publisher = [[NASA Earth Observatory]]',
12 => ' | date = 2001-04-16',
13 => ' | url = http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=4842',
14 => ' | accessdate = 2008-08-11',
15 => '}}</ref>]]',
16 => '[[Biodiversity hotspot]]s are chiefly [[tropical]] regions that feature high concentrations of [[Endemism|endemic]] species and, when all hotspots are combined, may contain over half of the world’s [[Terrestrial animal|terrestrial]] species.<ref name="Cincotta">Cincotta & Engelman, 2000</ref> These hotspots are suffering from habitat loss and destruction.',
17 => 'Most of the natural habitat on islands and in areas of high human population density has already been destroyed (WRI, 2003). Islands suffering extreme habitat destruction include [[New Zealand]], [[Madagascar]], the [[Philippines]], and [[Japan]].<ref name="Primack">Primack, 2006</ref> South and East Asia — especially [[China]], [[India]], [[Malaysia]], [[Indonesia]], and Japan — and many areas in [[West Africa]] have extremely dense human populations that allow little room for natural habitat. Marine areas close to highly populated [[coast]]al cities also face degradation of their [[coral reef]]s or other marine habitat. These areas include the eastern coasts of Asia and Africa, northern coasts of [[South America]], and the [[Caribbean Sea]] and its associated [[island]]s.<ref name="Primack"/>',
18 => false,
19 => 'Regions of un[[sustainable agriculture]] or unstable governments, which may go hand-in-hand, typically experience high rates of habitat destruction. [[Central America]], [[Sub-Saharan Africa]], and the [[Amazonian tropical rainforest]] areas of [[South America]] are the main regions with unsustainable agricultural practices and/or government mismanagement.<ref name="Primack"/>',
20 => false,
21 => 'Areas of high agricultural output tend to have the highest extent of habitat destruction. In the U.S., less than 25% of native vegetation remains in many parts of the [[Eastern United States|East]] and [[Midwestern United States|Midwest]].<ref name="Stein">Stein et al., 2000</ref> Only 15% of land area remains unmodified by human activities in all of Europe.<ref name="Primack"/>',
22 => false,
23 => '==Ecosystems==',
24 => '[[File:Lacanja burn.JPG|thumb|Jungle burned for agriculture in southern Mexico]]',
25 => '[[Tropical rainforest]]s have received most of the attention concerning the destruction of habitat. From the approximately 16 million square kilometers of tropical rainforest habitat that originally existed worldwide, less than 9 million square kilometers remain today.<ref name="Primack"/> The current rate of [[deforestation]] is 160,000 square kilometers per year, which equates to a loss of approximately 1% of original forest habitat each year.<ref name="Laurance">Laurance, 1999</ref>',
26 => false,
27 => 'Other forest [[ecosystem]]s have suffered as much or more destruction as tropical [[rainforest]]s. [[Farming]] and [[logging]] have severely disturbed at least 94% of [[Temperate broadleaf and mixed forests|temperate broadleaf forests]]; many [[old growth forest]] stands have lost more than 98% of their previous area because of human activities.<ref name="Primack"/> [[Tropical and subtropical dry broadleaf forests|Tropical deciduous dry forests]] are easier to [[Slash and burn|clear and burn]] and are more suitable for agriculture and [[cattle ranching]] than tropical rainforests; consequently, less than 0.1% of [[Tropical and subtropical dry broadleaf forests|dry forests in Central America's Pacific Coast]] and less than 8% in [[Madagascar dry deciduous forests|Madagascar]] remain from their original extents.<ref name="Laurance"/>',
28 => false,
29 => '[[File:Farmland-batang bungo.jpg|thumb|left|Farmers near newly cleared land within Taman Nasional Kerinci Seblat ([[Kerinci Seblat National Park]]), [[Sumatra]].]]',
30 => 'Plains and [[desert]] areas have been degraded to a lesser extent. Only 10-20% of the world's [[drylands]], which include [[temperate grasslands, savannas, and shrublands]], [[Scrubland|scrub]], and [[Temperate deciduous forest|deciduous forests]], have been somewhat degraded.<ref>Kauffman & Pyke, 2001</ref> But included in that 10-20% of land is the approximately 9 million square kilometers of seasonally dry-lands that humans have converted to deserts through the process of desertification.<ref name="Primack"/> The [[tallgrass prairie]]s of North America, on the other hand, have less than 3% of natural habitat remaining that has not been converted to farmland.<ref>White et al., 2000</ref>',
31 => false,
32 => '[[Wetland]]s and marine areas have endured high levels of habitat destruction. More than 50% of wetlands in the U.S. have been destroyed in just the last 200 years.<ref name="Stein"/> Between 60% and 70% of European wetlands have been completely destroyed.<ref>Ravenga et al., 2000</ref> About one-fifth (20%) of marine coastal areas have been highly modified by humans.<ref>Burke et al., 2000</ref> One-fifth of coral reefs have also been destroyed, and another fifth has been severely degraded by [[overfishing]], pollution, and [[invasive species]]; 90% of the Philippines’ coral reefs alone have been destroyed.<ref name="MEA">MEA, 2005</ref> Finally, over 35% [[Coastal ecosystems|mangrove ecosystems]] worldwide have been destroyed.<ref name="MEA"/>',
33 => '{{clear}}',
34 => false,
35 => '==Natural causes==',
36 => 'Habitat destruction through natural processes such as volcanism, [[fire]], and climate change is well documented in the fossil record.<ref name="SahneyBentonFerry2010LinksDiversityVertebrates"/> One study shows that habitat fragmentation of tropical rainforests in Euramerica 300 million years ago led to a great loss of amphibian diversity, but simultaneously the drier climate spurred on a burst of diversity among reptiles.<ref name="SahneyBentonFerry2010LinksDiversityVertebrates"/>',
37 => false,
38 => '==Human causes==',
39 => '[[File:Amazonie deforestation.jpg|thumb|Deforestation and roads in Amazonia, the [[Amazon Rainforest]].]]',
40 => false,
41 => 'Habitat destruction caused by humans includes [[land conversion]] from forests, etc. to [[arable land]], [[urban sprawl]], [[Public works|infrastructure development]], and other anthropogenic changes to the characteristics of land. Habitat degradation, fragmentation, and [[pollution]] are aspects of habitat destruction caused by humans that do not necessarily involve over destruction of habitat, yet result in habitat collapse. [[Desertification]], [[deforestation]], and [[Coral bleaching|coral reef degradation]] are specific types of habitat destruction for those areas ([[desert]]s, [[forest]]s, [[coral reef]]s).',
42 => false,
43 => 'Geist and Lambin (2002) assessed 152 case studies of net losses of tropical forest cover to determine any patterns in the proximate and underlying causes of tropical deforestation. Their results, yielded as percentages of the case studies in which each parameter was a significant factor, provide a quantitative prioritization of which proximate and underlying causes were the most significant. The proximate causes were clustered into broad categories of [[agricultural expansion]] (96%), [[infrastructure expansion]] (72%), and [[wood extraction]] (67%). Therefore, according to this study, [[forest conversion]] to agriculture is the main land use change responsible for tropical deforestation. The specific categories reveal further insight into the specific causes of tropical deforestation: transport extension (64%), commercial wood extraction (52%), [[permanent cultivation]] (48%), [[cattle ranching]] (46%), shifting ([[slash and burn]]) cultivation (41%), [[subsistence agriculture]] (40%), and [[fuel wood]] extraction for domestic use (28%). One result is that [[shifting cultivation]] is not the primary cause of deforestation in all world regions, while transport extension (including the [[Road construction|construction of new roads]]) is the largest single proximate factor responsible for deforestation.<ref name="Geist"/>',
44 => false,
45 => '==Drivers==',
46 => '[[File:Crowded Nanjing Road in Shanghai.jpeg|thumb|Nanjing Road in Shanghai]]',
47 => 'While the above-mentioned activities are the proximal or direct causes of habitat destruction in that they actually destroy habitat, this still does not identify why humans destroy habitat. The forces that cause humans to destroy habitat are known as ''drivers'' of habitat destruction. [[Demographic]], economic, sociopolitical, scientific and technological, and cultural drivers all contribute to habitat destruction.<ref name="MEA"/>',
48 => false,
49 => 'Demographic drivers include the [[Human overpopulation|expanding human population]]; rate of [[Population growth|population increase]] over time; [[Population density|spatial distribution]] of people in a given area ([[List of urban areas by population|urban]] versus rural), ecosystem type, and country; and the combined effects of poverty, age, family planning, gender, and education status of people in certain areas.<ref name="MEA"/> Most of the exponential human population growth worldwide is occurring in or close to [[biodiversity hotspots]].<ref name="Cincotta"/> This may explain why human population density accounts for 87.9% of the variation in numbers of [[threatened species]] across 114 countries, providing indisputable evidence that people play the largest role in decreasing [[biodiversity]].<ref>McKee et al., 2003</ref> The boom in human population and migration of people into such species-rich regions are making [[conservation biology|conservation efforts]] not only more urgent but also more likely to conflict with local human interests.<ref name="Cincotta"/> The high local population density in such areas is directly correlated to the poverty status of the local people, most of whom lacking an education and family planning.<ref name="Geist">Geist & Lambin, 2002</ref>',
50 => false,
51 => 'From the Geist and Lambin (2002) study described in the previous section, the underlying driving forces were prioritized as follows (with the percent of the 152 cases the factor played a significant role in): economic factors (81%), institutional or policy factors (78%), technological factors (70%), cultural or socio-political factors (66%), and demographic factors (61%). The main economic factors included commercialization and growth of timber markets (68%), which are driven by national and international demands; urban industrial growth (38%); low domestic costs for land, labor, fuel, and timber (32%); and increases in product prices mainly for cash crops (25%). Institutional and policy factors included formal pro-deforestation policies on land development (40%), economic growth including colonization and infrastructure improvement (34%), and subsidies for land-based activities (26%); property rights and land-tenure insecurity (44%); and policy failures such as corruption, lawlessness, or mismanagement (42%). The main technological factor was the poor application of technology in the wood industry (45%), which leads to wasteful logging practices. Within the broad category of cultural and sociopolitical factors are public attitudes and values (63%), individual/household behavior (53%), public unconcern toward forest environments (43%), missing basic values (36%), and unconcern by individuals (32%). Demographic factors were the in-migration of colonizing settlers into sparsely populated forest areas (38%) and growing population density — a result of the first factor — in those areas (25%).',
52 => false,
53 => 'There are also feedbacks and interactions among the proximate and underlying causes of deforestation that can amplify the process. Road construction has the largest feedback effect, because it interacts with—and leads to—the establishment of new settlements and more people, which causes a growth in wood (logging) and food markets.<ref name="Geist"/> Growth in these markets, in turn, progresses the commercialization of agriculture and logging industries. When these industries become commercialized, they must become more efficient by utilizing larger or more modern machinery that often are worse on the habitat than traditional farming and logging methods. Either way, more land is cleared more rapidly for commercial markets. This common feedback example manifests just how closely related the proximate and underlying causes are to each other.',
54 => false,
55 => '==Impact on human population==',
56 => '[[File:KatrinaNewOrleansFlooded edit2.jpg|thumb|The draining and development of coastal wetlands that previously protected the Gulf Coast contributed to severe flooding in New Orleans, Louisiana in the aftermath of [[Hurricane Katrina]].<ref>Tibbetts, 2006</ref>]]',
57 => 'Habitat destruction vastly increases an area's vulnerability to [[natural disaster]]s like [[flood]] and [[drought]], [[crop failure]], [[spread of disease]], and [[water contamination]].<ref name="MEA"/> On the other hand, a healthy ecosystem with good management practices will reduce the chance of these events happening, or will at least mitigate adverse impacts.',
58 => false,
59 => 'Agricultural land can actually suffer from the destruction of the surrounding landscape. Over the past 50 years, the destruction of habitat surrounding agricultural land has degraded approximately 40% of agricultural land worldwide via [[erosion]], [[salinization]], [[Soil compaction|compaction]], [[Natural resource#Depletion|nutrient depletion]], [[pollution]], and [[urbanization]].<ref name="MEA"/> Humans also lose direct uses of natural habitat when habitat is destroyed. Aesthetic uses such as [[birdwatching]], recreational uses like [[hunting]] and [[fishing]], and [[ecotourism]] usually rely upon virtually undisturbed habitat. Many people value the complexity of the natural world and are disturbed by the loss of natural habitats and animal or plant species worldwide.',
60 => false,
61 => 'Probably the most profound impact that habitat destruction has on people is the loss of many valuable [[ecosystem services]]. Habitat destruction has altered nitrogen, phosphorus, sulfur, and [[carbon cycle]]s, which has increased the frequency and severity of [[acid rain]], [[algal bloom]]s, and [[fish kill]]s in rivers and oceans and contributed tremendously to global [[climate change]].<ref name="MEA"/> One ecosystem service whose significance is becoming more realized is [[Climate|climate regulation]]. On a local scale, trees provide windbreaks and shade; on a regional scale, [[Transpiration|plant transpiration]] recycles rainwater and maintains constant annual rainfall; on a global scale, plants (especially trees from tropical rainforests) from around the world counter the accumulation of [[greenhouse gas]]es in the atmosphere by [[Carbon dioxide sink|sequestering carbon dioxide]] through [[photosynthesis]].<ref name="Primack"/> Other ecosystem services that are diminished or lost altogether as a result of habitat destruction include [[watershed management]], [[nitrogen fixation]], oxygen production, [[pollination]] (see [[pollinator decline]]),<ref>{{cite journal|journal=PLoS One|volume=8|issue=5|year=2013|doi=10.1371/journal.pone.0063421|pmc=3661593|title=Plant Pollinator Networks along a Gradient of Urbanisation|author1=Benoît Geslin|author2=Benoit Gauzens|author3=Elisa Thébault|author4=Isabelle Dajoz}}</ref> [[waste treatment]] (i.e., the [[Decomposition|breaking down]] and immobilization of [[toxic]] pollutants), and [[Nutrient cycle|nutrient recycling]] of [[sewage]] or [[agricultural runoff]].<ref name="Primack"/>',
62 => false,
63 => 'The loss of trees from the tropical rainforests alone represents a substantial diminishing of the earth’s ability to produce oxygen and use up carbon dioxide. These services are becoming even more important as increasing [[carbon dioxide]] levels is one of the main contributors to global [[climate change]].',
64 => false,
65 => 'The [[Biodiversity loss|loss of biodiversity]] may not directly affect humans, but the indirect effects of losing many species as well as the diversity of ecosystems in general are enormous. When biodiversity is lost, the environment loses many species that provide valuable and unique roles to the ecosystem. The environment and all its inhabitants rely on biodiversity to recover from extreme environmental conditions. When too much biodiversity is lost, a catastrophic event such as an earthquake, flood, or volcanic eruption could cause an ecosystem to crash, and humans would obviously suffer from that. Loss of biodiversity also means that humans are losing animals that could have served as biological control agents and plants that could potentially provide higher-yielding crop varieties, pharmaceutical drugs to cure existing or future diseases or cancer, and new resistant crop varieties for agricultural species susceptible to pesticide-resistant insects or virulent strains of [[fungi]], [[virus]]es, and [[bacteria]].<ref name="Primack"/>',
66 => false,
67 => 'The negative effects of habitat destruction usually impact rural populations more directly than urban populations.<ref name="MEA"/> Across the globe, poor people suffer the most when natural habitat is destroyed, because less natural habitat means less natural resources per capita, yet wealthier people and countries simply have to pay more to continue to receive more than their per capita share of natural resources.',
68 => false,
69 => 'Another way to view the negative effects of habitat destruction is to look at the opportunity cost of keeping an area undisturbed. In other words, what are people losing out on by taking away a given habitat? A country may increase its food supply by converting forest land to row-crop agriculture, but the value of the same land may be much larger when it can supply natural resources or services such as clean water, timber, ecotourism, or flood regulation and drought control.<ref name="MEA"/>',
70 => false,
71 => '==Outlook==',
72 => 'The [[Human overpopulation|rapid expansion of the global human population]] is increasing the world’s food requirement substantially. Simple logic instructs that more people will require more food. In fact, as the world’s population increases dramatically, agricultural output will need to increase by at least 50%, over the next 30 years.<ref name="Tilman">Tilman et al., 2001</ref> In the past, continually moving to new land and soils provided a boost in food production to appease the global food demand. That easy fix will no longer be available, however, as more than 98% of all land suitable for agriculture is already in use or degraded beyond repair.<ref>Sanderson et al., 2002</ref>',
73 => false,
74 => 'The impending global [[food crisis]] will be a major source of habitat destruction. Commercial farmers are going to become desperate to produce more food from the same amount of land, so they will use more [[fertilizer]]s and less concern for the environment to meet the market demand. Others will seek out new land or will convert other land-uses to agriculture. Agricultural intensification will become widespread at the cost of the environment and its inhabitants. Species will be pushed out of their habitat either directly by habitat destruction or indirectly by fragmentation, [[environmental degradation|degradation]], or [[pollution]]. Any efforts to protect the world’s remaining natural habitat and biodiversity will compete directly with humans’ growing demand for natural resources, especially new agricultural lands.<ref name="Tilman"/>',
75 => false,
76 => '==Solutions==',
77 => '[[File:Hawaii turtle.JPG|thumb|''[[Chelonia mydas]]'' on a Hawaiian coral reef. Although the endangered species is protected, habitat loss from human development is a major reason for the loss of [[green turtle]] nesting beaches.]]',
78 => 'In most cases of tropical deforestation, three to four underlying causes are driving two to three proximate causes.<ref name="Geist"/> This means that a universal policy for controlling tropical deforestation would not be able to address the unique combination of proximate and underlying causes of deforestation in each country.<ref name="Geist"/> Before any local, national, or international deforestation policies are written and enforced, governmental leaders must acquire a detailed understanding of the complex combination of proximate causes and underlying driving forces of deforestation in a given area or country.<ref name="Geist"/> This concept, along with many other results about tropical deforestation from the Geist and Lambin study, can easily be applied to habitat destruction in general. Governmental leaders need to take action by addressing the underlying driving forces, rather than merely regulating the proximate causes. In a broader sense, governmental bodies at a local, national, and international scale need to emphasize the following:',
79 => false,
80 => '#Considering the many irreplaceable ecosystem services provided by natural habitats.',
81 => '#Protecting remaining intact sections of natural habitat.',
82 => '#Educating the public about the importance of natural habitat and biodiversity.',
83 => '#Developing [[family planning]] programs in areas of rapid population growth.',
84 => '#Finding ecological ways to increase agricultural output without increasing the total land in production.',
85 => '#Preserving habitat corridors to minimize prior damage from fragmented habitats.',
86 => '#Reduce [[human population]] and expansion.',
87 => false,
88 => '==Notes==',
89 => '{{reflist|2}}',
90 => false,
91 => '==References==',
92 => '{{refbegin|2}}',
93 => '*Barbault, R. and S. D. Sastrapradja. 1995. Generation, maintenance and loss of biodiversity. Global Biodiversity Assessment, Cambridge Univ. Press, Cambridge pp. 193–274.',
94 => '*Burke, L., Y. Kura, K. Kassem, C. Ravenga, M. Spalding, and D. McAllister. 2000. Pilot Assessment of Global Ecosystems: Coastal Ecosystems. World Resources Institute, Washington, D.C.',
95 => '*Cincotta, R.P., and R. Engelman. 2000. Nature's place: human population density and the future of biological diversity. Population Action International. Washington, D.C.',
96 => '*{{cite journal |author1=Geist H. J. |author2=Lambin E. E. | year = 2002 | title = Proximate causes and underlying driving forces of tropical deforestation | url = | journal = BioScience | volume = 52 | issue = 2| pages = 143–150 | doi=10.1641/0006-3568(2002)052[0143:PCAUDF]2.0.CO;2}}',
97 => '*Kauffman, J. B. and D. A. Pyke. 2001. Range ecology, global livestock influences. In S. A. Levin (ed.), Encyclopedia of Biodiversity 5: 33-52. Academic Press, San Diego, CA.',
98 => '*{{cite journal | author = Laurance W. F. | year = 1999 | title = Reflections on the tropical deforestation crisis | url = | journal = Biological Conservation | volume = 91 | issue = | pages = 109–117 | doi=10.1016/S0006-3207(99)00088-9}}',
99 => '*{{cite journal |author1=McKee J. K. |author2=Sciulli P.W. |author3=Fooce C. D. |author4=Waite T. A. | year = 2003 | title = Forecasting global biodiversity threats associated with human population growth | url = | journal = Biological Conservation | volume = 115 | issue = | pages = 161–164 | doi=10.1016/s0006-3207(03)00099-5}}',
100 => '*Millennium Ecosystem Assessment (Program). 2005. [https://books.google.com/books?id=UFVmiSAr-okC&dq=Ecosystems+and+Human+Well-Being Ecosystems and Human Well-Being]. Millennium Ecosystem Assessment. Island Press, Covelo, CA.',
101 => '*Primack, R. B. 2006. Essentials of Conservation Biology. 4th Ed. Habitat destruction, pages 177-188. Sinauer Associates, Sunderland, MA.',
102 => '*{{cite journal |author1=Pimm Stuart L. |author2=Raven Peter | year = 2000 | title = Biodiversity: Extinction by numbers | url = | journal = Nature | volume = 403 | issue = 6772| pages = 843–845 | doi = 10.1038/35002708 | pmid=10706267}}',
103 => '*Ravenga, C., J. Brunner, N. Henninger, K. Kassem, and R. Payne. 2000. Pilot Analysis of Global Ecosystems: Wetland Ecosystems. World Resources Institute, Washington, D.C.',
104 => '*{{cite journal |author1=Sahney S. |author2=Benton M.J. |author3=Falcon-Lang H.J. | year = 2010 | title = Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euramerica | url = | journal = Geology | volume = 38 | issue = | pages = 1079–1082 | doi=10.1130/G31182.1}}',
105 => '*{{cite journal |author1=Sanderson E. W. |author2=Jaiteh M. |author3=Levy M. A. |author4=Redford K. H. |author5=Wannebo A. V. |author6=Woolmer G. | year = 2002 | title = The human footprint and the last of the wild | url = | journal = BioScience | volume = 52 | issue = 10| pages = 891–904 | doi=10.1641/0006-3568(2002)052[0891:thfatl]2.0.co;2}}',
106 => '*Scholes, R. J. and R. Biggs (eds.). 2004. Ecosystem services in Southern Africa: a regional assessment. The regional scale component of the Southern African Millennium Ecosystem Assessment. CSIR, Pretoria, South Africa.',
107 => '*Stein, B. A., L. S. Kutner, and J. S. Adams (eds.). 2000. Precious Heritage: The Status of Biodiversity in the United States. Oxford University Press, New York.',
108 => '*{{cite journal | author = Temple S. A. | year = 1986 | title = The problem of avian extinctions | url = | journal = Ornithology | volume = 3 | issue = | pages = 453–485 | doi=10.1007/978-1-4615-6784-4_11}}',
109 => '*{{cite journal | author = Tibbetts John | year = 2006 | title = Louisiana's Wetlands: A Lesson in Nature Appreciation | pmc = 1332684 | journal = Environ Health Perspect | volume = 114 | issue = 1| pages = A40–A43 | pmid=16393646 | doi=10.1289/ehp.114-a40}}',
110 => '*{{cite journal |author1=Tilman D. |author2=Fargione J. |author3=Wolff B. |author4=D'Antonio C. |author5=Dobson A. |author6=Howarth R. |author7=Schindler D. |author8=Schlesinger W. H. |author9=Simberloff D. | year = 2001 | title = Forecasting agriculturally driven global environmental change | url = | journal = Science | volume = 292 | issue = | pages = 281–284 | doi=10.1126/science.1057544 | pmid=11303102|display-authors=etal}}',
111 => '*White, R. P., S. Murray, and M. Rohweder. 2000. Pilot Assessment of Global Ecosystems: Grassland Ecosystems. World Resources Institute, Washington, D. C.',
112 => '*WRI. 2003. World Resources 2002-2004: Decisions for the Earth: Balance, voice, and power. 328 pp. World Resources Institute, Washington, D.C.',
113 => false,
114 => '{{refend}}',
115 => false,
116 => '{{Extinction}}',
117 => '{{human impact on the environment|state=expanded}}',
118 => '{{threatened species}}',
119 => '{{population}}',
120 => false,
121 => '[[Category:Habitats| ]]',
122 => '[[Category:Habitat]]',
123 => '[[Category:Environmental conservation]]',
124 => '[[Category:Environmental terminology]]',
125 => '[[Category:Environmental impact by effect]]',
126 => false,
127 => '[[fr:Perturbation écologique]]'
] |