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{{Short description|Process by which fertile areas of land become increasingly arid}}
{{distinguish|NLRB election procedures#Decertification elections{{!}}Decertification|Desertion}}
{{Use dmy dates|date=February 2024}}
[[File:Global distribution of dryland subtypes based on the aridity index.png|upright=1.4|thumb|Global distribution of dryland subtypes based on the [[aridity index]] computed over a 30-year average during 1981 to 2010. Typical deserts are indicated by the hyper-arid category (light yellow)<ref>{{Cite book |last=European Commission. Joint Research Centre. |url=https://data.europa.eu/doi/10.2760/9205 |title=World atlas of desertification :rethinking land degradation and sustainable land management. |date=2018 |publisher=Publications Office |location=LU |doi=10.2760/9205}}</ref>]]
[[File:Desertification map.png|thumb|upright=1.75|World map from 1998 showing global desertification vulnerability]]
'''Desertification''' is a type of gradual [[land degradation]] inof [[drylandsSoil fertility|fertile]] inland whichinto biologicalarid productivity is lost[[desert]] due to a combination of natural processes or induced byand human activities whereby fertile areas become arid.<ref>{{Cite web |date=2023-08-23 |title=Desertification {{!}} Description, Causes, & Impacts {{!}} Britannica |url=https://www.britannica.com/science/desertification |access-date=2023-09-22 |website=www.britannica.com |language=en}}</ref><ref>{{Cite web |title=Desertification - an overview {{!}} ScienceDirect Topics |url=https://www.sciencedirect.com/topics/earth-and-planetary-sciences/desertification |access-date=2022-04-03 |website=www.sciencedirect.com |archive-date=2022-04-03 |archive-url=https://web.archive.org/web/20220403121044/https://www.sciencedirect.com/topics/earth-and-planetary-sciences/desertification |url-status=live }}</ref> It is theThis spread of arid areas is caused by a variety of factors, such as [[overexploitation]] of [[soil]] as a result of human activity and the [[effects of climate change]].<ref>{{cite web |title=Sustainable development of drylands and combating desertification |url=http://www.fao.org/docrep/v0265e/v0265e01.htm |url-status=live |archive-url=https://web.archive.org/web/20170804222104/http://www.fao.org/docrep/v0265e/v0265e01.htm |archive-date=4 August 2017 |access-date=21 June 2016}}</ref><ref name="Zeng L17401">{{Cite journal |last1=Zeng |first1=Ning |last2=Yoon |first2=Jinho |date=1 September 2009 |title=Expansion of the world's deserts due to vegetation-albedo feedback under global warming |journal=Geophysical Research Letters |volume=36 |issue=17 |page=L17401 |bibcode=2009GeoRL..3617401Z |doi=10.1029/2009GL039699 |issn=1944-8007 |s2cid=1708267 |doi-access=free}}</ref> Geographic areas most affected includeare thelocated in Africa ([[Sahel]] region in Africa), theAsia ([[Gobi Desert]] and [[Mongolia]]) in Asia as well asand parts of [[South America]]. [[Drylands]] occupy approximately 40–41% of Earth's land area and are home to more than 2 &nbsp;billion people.<ref name=":5">[https://unemg.org/2018/images/emgdocs/publications/Global_Drylands_Full_Report.pdf Global Drylands Report] unemg.org 2018</ref> Effects of desertification include [[Sand storm|sand and dust storms]], [[Food security|food insecurity]], and [[poverty]].
 
EffectsHumans ofcan fight desertification includein various ways. For instance, [[SandSoil stormregeneration|sandimproving and dustsoil stormsquality]], [[FoodReclaiming securitydesert|foodgreening insecuritydeserts]], vegetationmanaging patterning[[grazing]] better, and increasing poverty. There are many possible countermeasures suchplanting astrees ([[reforestation]], and [[soil regenerationafforestation]],) [[desertcan reclamation]]all andhelp managedreverse [[grazing]]desertification.
 
Throughout geological history, the development of [[desert]]s has occurred naturally over long intervals of time.<ref name=":1" /> The modern study of desertification emerged from the study of the [[Sahel drought|1980s drought]] in the [[Sahel]].<ref name=":6" />
Throughout geological history, the development of [[desert]]s has occurred naturally. In recent times, the influences of human activity, improper land management, [[deforestation]] and [[climate change]] on desertification is the subject of many scientific investigations.<ref>{{cite journal |last1=Liu |first1=Ye |last2=Xue |first2=Yongkang |title=Expansion of the Sahara Desert and shrinking of frozen land of the Arctic |journal=Scientific Reports |date=5 March 2020 |volume=10 |issue=1 |pages=4109 |doi=10.1038/s41598-020-61085-0 |pmid=32139761 |pmc=7057959 |bibcode=2020NatSR..10.4109L }}</ref><ref>{{cite journal |last1=An |first1=Hui |last2=Tang |first2=Zhuangsheng |last3=Keesstra |first3=Saskia |last4=Shangguan |first4=Zhouping |title=Impact of desertification on soil and plant nutrient stoichiometry in a desert grassland |journal=Scientific Reports |date=1 July 2019 |volume=9 |issue=1 |pages=9422 |doi=10.1038/s41598-019-45927-0 |pmid=31263198 |pmc=6603008 |bibcode=2019NatSR...9.9422A }}</ref><ref>{{cite journal |last1=Han |first1=Xueying |last2=Jia |first2=Guangpu |last3=Yang |first3=Guang |last4=Wang |first4=Ning |last5=Liu |first5=Feng |last6=Chen |first6=Haoyu |last7=Guo |first7=Xinyu |last8=Yang |first8=Wenbin |last9=Liu |first9=Jing |title=Spatiotemporal dynamic evolution and driving factors of desertification in the Mu Us Sandy Land in 30 years |journal=Scientific Reports |date=10 December 2020 |volume=10 |issue=1 |pages=21734 |doi=10.1038/s41598-020-78665-9 |pmid=33303886 |pmc=7729393 |bibcode=2020NatSR..1021734H }}</ref>
 
==Definitions==
}}</ref>Desertification is a gradual process of increased soil [[aridity]]. Desertification has been defined in the text of the [[United Nations Convention to Combat Desertification]] (UNCCD) as "land degradation in arid, semi-arid and dry sub-humid regions resulting from various factors, including climatic variations and human activities according to Hulme and Kelly, (1993)."<ref>{{Cite journal |last1=Hulme |first1=Mike |last2=Kelly |first2=Mick |date=1993 |title=Exploring the links between Desertification and Climate Change |url=http://www.tandfonline.com/doi/abs/10.1080/00139157.1993.9929106 |journal=Environment: Science and Policy for Sustainable Development |language=en |volume=35 |issue=6 |pages=4–45 |bibcode=1993ESPSD..35f...4H |doi=10.1080/00139157.1993.9929106 |bibcode=1993ESPSD..35f...4H |issn=0013-9157}}</ref>▼
As recently as 2005, considerable controversy existed over the proper
 
definition of the term "desertification." Helmut Geist (2005) identified more than 100 formal definitions.<ref>{{Cite book |last=Geist |first=Helmut▼
[https://thengr21.com/%e0%a4%ae%e0%a4%b0%e0%a5%81%e0%a4%b8%e0%a5%8d%e0%a4%a5%e0%a4%b2%e0%a5%80%e0%a4%95%e0%a4%b0%e0%a4%a3-2/ Definition of Desert] – That area of ​​the earth where the sum of rain and snowfall is much less than other areas, where the annual average rainfall is less than 25CM. Definition by UNO (1995) – Land degradation in barren, humid and sub-humid areas due to climate change and human activities is called desertification.
|url=https://www.taylorfrancis.com/books/mono/10.4324/9781315240855/causes-progression-desertification-helmut-geist |title=The Causes and Progression of Desertification |date=2017-10-01 |publisher=Routledge |isbn=978-1-315-24085-5 |location=London |doi=10.4324/9781315240855}}</ref> The most widely accepted of these was that of the [[Princeton University]] Dictionary which defined it as "the process of fertile land ''transforming into desert'' typically as a result of [[deforestation]], [[drought]] or improper/inappropriate agriculture".{{cn|date=October 2023}} This definition clearly demonstrated the interconnectedness of desertification and human activities, in particular land use and land management practices. It also highlighted the economic, social and environmental implications of desertification.<br />However, this original understanding that desertification involved the physical expansion of deserts has been rejected as the concept has further evolved since then.<ref name="EB2">{{cite encyclopedia▼
 
▲definitionAs of 2005, considerable controversy existed over the termproper "desertification."definition Helmutof Geistthe (2005)term identified''desertification'' with more than 100 formal definitions in existence.<ref>{{Cite book |last=Geist |first=Helmut
▲|url=https://www.taylorfrancis.com/books/mono/10.4324/9781315240855/causes-progression-desertification-helmut-geist |title=The Causes and Progression of Desertification |date=2017-10-01 |publisher=Routledge |isbn=978-1-315-24085-5 |location=London |doi=10.4324/9781315240855}}</ref> The most widely accepted of these was that of the [[Princeton University]] Dictionary which defined it as "the process of fertile land ''transforming into desert'' typically as a result of [[deforestation]], [[drought]] or improper/inappropriate agriculture".{{cn|date=October 2023}} This definition clearly demonstrated the interconnectedness of desertification and human activities, in particular land use and land management practices. It also highlighted the economic, social and environmental implications of desertification.<br />However, this original understanding that desertification involved the physical expansion of deserts has been rejected as the concept has further evolved since then.<ref name="EB2">{{cite encyclopedia
| title = Desertification
| first1 = John P.
Line 24 ⟶ 27:
| quote = The concept does not refer to the physical expansion of existing deserts but rather to the various processes that threaten all dryland ecosystems.
 
}}</ref>
▲}}</ref> Desertification has been defined in the text of the [[United Nations Convention to Combat Desertification]] (UNCCD) as "land degradation in arid, semi-arid and dry sub-humid regions resulting from various factors, including climatic variations and human activities according to Hulme and Kelly, (1993)."<ref>{{Cite journal |last1=Hulme |first1=Mike |last2=Kelly |first2=Mick |date=1993 |title=Exploring the links between Desertification and Climate Change |url=http://www.tandfonline.com/doi/abs/10.1080/00139157.1993.9929106 |journal=Environment: Science and Policy for Sustainable Development |language=en |volume=35 |issue=6 |pages=4–45 |doi=10.1080/00139157.1993.9929106 |bibcode=1993ESPSD..35f...4H |issn=0013-9157}}</ref>
 
There exists also controversy around the sub-grouping of types of desertification, including, for example, the validity and usefulness of such terms as "man-made desert" and "non-pattern desert".<ref>{{Cite journal |last1=Geist |first1=Helmut J. |last2=Lambin |first2=Eric F. |date=2004 |title=Dynamic Causal Patterns of Desertification |journal=BioScience |language=en |volume=54 |issue=9 |pages=817 |doi=10.1641/0006-3568(2004)054[0817:DCPOD]2.0.CO;2 |issn=0006-3568|doi-access=free }}</ref>
 
==Geographic areas affected==▼
[[Drylands]] occupy approximately 40–41% of Earth's land area and are home to more than 2 billion people.<ref name=":4">{{Cite book |title=Governing global desertification: linking environmental degradation, poverty and participation |date=2006 |publisher=Ashgate [u.a.] |isbn=978-0-7546-4359-3 |editor-last=Johnson |editor-first=Pierre-Marc |series=Global environmental governance series |location=Aldershot |editor-last2=Johnson |editor-first2=Pierre Marc}}</ref><ref name=":5">[https://unemg.org/2018/images/emgdocs/publications/Global_Drylands_Full_Report.pdf Global Drylands Report] unemg.org 2018</ref> It has been estimated that some 10–20% of drylands are already degraded, the total area affected by desertification being between 6 and 12 million square kilometers, that about 1–6% of the inhabitants of drylands live in desertified areas, and that a billion people are under threat from further desertification.<ref name="holtz">{{cite web|url=https://www.unccd.int/un-decade-deserts-and-fight-against-desertification-impact-and-role-drylands|title=UNCCD: Impact and role of drylands|date=10 October 2017|website=UNCCD|access-date=7 November 2019|archive-date=7 November 2019|archive-url=https://web.archive.org/web/20191107121026/https://www.unccd.int/un-decade-deserts-and-fight-against-desertification-impact-and-role-drylands|url-status=dead}}</ref><ref>{{cite book|author=World Bank|title=Gender in agriculture sourcebook|publisher=World Bank Publications|year=2009|isbn=978-0-8213-7587-7|page=454|url=https://books.google.com/books?id=XxBrq6hTs_UC&pg=PA454|access-date=2016-05-16|archive-date=2023-07-30|archive-url=https://web.archive.org/web/20230730160546/https://books.google.com/books?id=XxBrq6hTs_UC&pg=PA454|url-status=live}}</ref>▼
 
===Sahel===▼
{{Further|Sahel#Desertification and soil loss}}▼
The impact of climate change and human activities on desertification are exemplified in the [[Sahel]] region of Africa. The region is characterized by a dry hot climate, high temperatures and low rainfall (100–600&nbsp;mm per year).<ref>{{Cite journal |last=Nicholson |first=Sharon E. |date=2013-02-17 |title=The West African Sahel: A Review of Recent Studies on the Rainfall Regime and Its Interannual Variability |journal=International Scholarly Research Notices |language=en |volume=2013 |pages=e453521 |doi=10.1155/2013/453521|doi-access=free }}</ref> So, droughts are the rule in the Sahel region.<ref>{{Cite web|url=http://earthobservatory.nasa.gov/Features/Desertification/desertification2.php|title=Defining Desertification : Feature Articles|last=Riebeek|first=Holli|date=2007-01-03|website=earthobservatory.nasa.gov|access-date=2016-11-30|archive-date=2016-12-01|archive-url=https://web.archive.org/web/20161201211259/http://earthobservatory.nasa.gov/Features/Desertification/desertification2.php|url-status=live}}</ref> The Sahel has lost approximately 650,000&nbsp;km<sup>2</sup> of its productive agricultural land over the past 50 years;<ref>[https://www.thegeographeronline.net/uploads/2/6/6/2/26629356/a116_sahel.pdf Environmental issues in the Sahel] Geo Factsheet</ref> the propagation of desertification in this area is considerable.<ref>{{cite journal |last1=Nicholson |first1=S. E. |last2=Tucker |first2=C. J. |last3=Ba |first3=M. B. |title=Desertification, Drought, and Surface Vegetation: An Example from the West African Sahel |journal=Bulletin of the American Meteorological Society |date=1 May 1998 |volume=79 |issue=5 |pages=815–830 |doi=10.1175/1520-0477(1998)079<0815:DDASVA>2.0.CO;2 |bibcode=1998BAMS...79..815N |doi-access=free }}</ref><ref>{{Cite web|title=Land Resource Stresses and Desertification in Africa|url=https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/use/?cid=nrcs142p2_054025|access-date=24 November 2020|website=United States Department of Agriculture|archive-date=1 April 2022|archive-url=https://web.archive.org/web/20220401055308/https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/use/?cid=nrcs142p2_054025|url-status=dead}}</ref>▼
[[File:Village Telly in Mali.jpg|thumb|[[Sahel]] region of Mali]]▼
The climate of the Sahara has undergone enormous variations over the last few hundred thousand years,<ref name="Lakes">{{Cite journal | title=Ancient Lakes of the Sahara | journal=American Scientist | volume=94 | year=2006 | pages= 58–65 |author1=Kevin White |author2=David J. Mattingly | issue=1 | doi=10.1511/2006.57.983}}</ref> oscillating between wet (grassland) and dry (desert) every 20,000 years<ref>{{cite news |url=http://news.mit.edu/2019/study-regulating-north-african-climate-0102 |title=A "pacemaker" for North African climate |author=Jennifer Chu |date=January 2, 2019 |publisher=MIT News |access-date=January 20, 2020 |archive-date=January 15, 2022 |archive-url=https://web.archive.org/web/20220115093627/https://news.mit.edu/2019/study-regulating-north-african-climate-0102 |url-status=live }}</ref> (a phenomenon believed to be caused by long-term changes in the [[North African climate cycle]] that alters the path of the [[North African Monsoon]], caused by an approximately 40,000-year cycle in which the [[axial tilt]] of the earth changes between 22° and 24.5°).<ref name="ReferenceA">{{cite book|last1=Houérou|first1=Henry N.|title=Bioclimatology and Biogeography of Africa|publisher=Springer Science & Business Media|isbn=978-3-540-85192-9|url=https://books.google.com/books?id=_Rvs7NkfeLEC&q=Sahara+rainfall+virtually+zero&pg=PA16|language=en|date=2008-12-10|access-date=2020-12-11|archive-date=2023-07-30|archive-url=https://web.archive.org/web/20230730160547/https://books.google.com/books?id=_Rvs7NkfeLEC&q=Sahara+rainfall+virtually+zero&pg=PA16|url-status=live}}</ref> Some statistics have shown that, since 1900, the Sahara has expanded by 250&nbsp;km to the south over a stretch of land from west to east 6,000&nbsp;km long.<ref>{{cite web|author=Christian Bouquet|title=Le Sahara entre ses deux rives. Éléments de délimitation par la géohistoire d'un espace de contraintes|website=Géoconfluences|date=December 2017|url=http://geoconfluences.ens-lyon.fr/informations-scientifiques/dossiers-regionaux/afrique-dynamiques-regionales/articles-scientifiques/sahara-entre-deux-rives|quote=Mais il aurait progressé de 250 km vers le sud depuis 1900 (Mainguet, 2003), et dépasserait donc 9 millions de km² soit 30 % de la superficie totale du continent africain.|access-date=2018-01-25|archive-date=2022-02-10|archive-url=https://web.archive.org/web/20220210001607/http://geoconfluences.ens-lyon.fr/informations-scientifiques/dossiers-regionaux/afrique-dynamiques-regionales/articles-scientifiques/sahara-entre-deux-rives|url-status=live}}</ref> ▼
 
[[Lake Chad]], located in the Sahel region, has undergone desiccation due to water withdrawal for irrigation and decrease in rainfall.<ref>{{cite journal |last1=Okpara |first1=Uche T. |last2=Stringer |first2=Lindsay C. |last3=Dougill |first3=Andrew J. |title=Lake drying and livelihood dynamics in Lake Chad: Unravelling the mechanisms, contexts and responses |journal=Ambio |date=November 2016 |volume=45 |issue=7 |pages=781–795 |doi=10.1007/s13280-016-0805-6 |pmid=27371137 |pmc=5055484 |bibcode=2016Ambio..45..781O }}</ref> The lake has shrunk by over 90% since 1987, displacing millions of inhabitants.<ref>{{Cite web |last=Jiang |first=Ingrid |date=2022-08-12 |title=A Remarkable Size Shrinking in Lake Chad |url=https://storymaps.arcgis.com/stories/e63a90f8552d4e5f98f4c56a56c06f9d |access-date=2023-09-22 |website=ArcGIS StoryMaps |language=en-ca}}</ref> Recent efforts have managed to make some progress toward its restoration, but it is still considered to be at risk of disappearing entirely.<ref name="Remote sensing appraisal of Lake Ch">{{cite journal |last1=Onamuti |first1=Olapeju Y. |last2=Okogbue |first2=Emmanuel C. |last3=Orimoloye |first3=Israel R. |date=8 November 2017 |title=Remote sensing appraisal of Lake Chad shrinkage connotes severe impacts on green economics and socio-economics of the catchment area |journal=Royal Society Open Science |volume=4 |issue=11 |pages=171120 |doi=10.1098/rsos.171120 |pmc=5717671 |pmid=29291097}}</ref>▼
 
To limit desertification the [[Great Green Wall (Africa)]] initiative was started in 2007 involving the planting of vegetation along a stretch of 7,775 kms, 15 kms wide, involving 22 countries to 2030.<ref>{{Cite web |title=Great Green Wall Initiative |url=https://www.unccd.int/our-work/ggwi |access-date=2023-09-22 |website=UNCCD |language=en}}</ref> The purpose of this mammoth planting initiative is to enhance retention of water in the ground following the seasonal rainfall, thus promoting land rehabilitation and future agriculture. Senegal has already contributed to the project by planting 50,000 acres of trees. It is said to have improved land quality and caused an increase in economic opportunity in the region.<ref>{{cite web | url=https://education.nationalgeographic.org/resource/great-green-wall/ | title=The Great Green Wall &#124; National Geographic Society | access-date=2022-12-22 | archive-date=2022-12-22 | archive-url=https://web.archive.org/web/20221222164123/https://education.nationalgeographic.org/resource/great-green-wall/ | url-status=live }}</ref>▼
 
===Gobi Desert and Mongolia===▼
{{See also|Environmental issues in Mongolia#Desertification}}▼
Another major area that is being impacted by desertification is the [[Gobi Desert]] located in Northern China and Southern Mongolia. The Gobi Desert is the fastest expanding desert on Earth, as it transforms over {{convert|3600|km2|sqmi|abbr=off}} of grassland into wasteland annually.<ref>{{Cite web |last=Rechtschaffen |first=Daniel |title=How China's Growing Deserts Are Choking The Country |url=https://www.forbes.com/sites/danielrechtschaffen/2017/09/18/how-chinas-growing-deserts-are-choking-the-country/ |access-date=2022-08-28 |website=Forbes |language=en |archive-date=2022-02-16 |archive-url=https://web.archive.org/web/20220216110308/https://www.forbes.com/sites/danielrechtschaffen/2017/09/18/how-chinas-growing-deserts-are-choking-the-country/ |url-status=live }}</ref> Although the Gobi Desert itself is still a distance away from [[Beijing]], reports from field studies state there are large sand dunes forming only 70&nbsp;km (43.5&nbsp;mi) outside the city.<ref>{{cite report|last=Welker|first=Lauren|url=http://www.geo.utexas.edu/courses/371c/project/2009/Welker_Desertification.pdf |archive-url=https://web.archive.org/web/20140124101958/http://www.geo.utexas.edu/courses/371c/project/2009/Welker_Desertification.pdf |archive-date=2014-01-24 |url-status=live |title=The Desertification of the Gobi Desert and Its Effect on Beijing |date=2009 |type=Unpublished manuscript |publisher=University of Texas-Austin School of Geosciences}}</ref><ref>{{Cite web |date=2020-03-25 |title=Gobi Desert: A Complete Guide to East Asia's Largest Desert |url=https://www.youngpioneertours.com/gobi-desert-guide/ |access-date=2022-04-03 |website=Young Pioneer Tours |language=en |archive-date=2023-07-30 |archive-url=https://web.archive.org/web/20230730160548/https://www.youngpioneertours.com/gobi-desert-guide/ |url-status=live }}</ref>▼
 
In [[Mongolia]], around 90% of grassland is considered [[vulnerability|vulnerable]] to desertification by the UN. An estimated 13% of desertification in Mongolia is caused by natural factors; the rest is due to human influence particularly overgrazing and increased erosion of soils in cultivated areas.<ref>{{Cite web |title=What Is Desertification and How Does It Impact Mongolia? |url=https://breathemongolia.org/en/news-article/desertification-impact-mongolia/ |access-date=2022-04-03 |website=Breathe Mongolia – English |language=en-US |archive-date=2022-04-01 |archive-url=https://web.archive.org/web/20220401180828/https://breathemongolia.org/en/news-article/desertification-impact-mongolia |url-status=live }}</ref><ref>{{Cite journal |last1=Han |first1=Jie |last2=Dai |first2=Han |last3=Gu |first3=Zhaolin |date=2021-12-01 |title=Sandstorms and desertification in Mongolia, an example of future climate events: a review |url=https://doi.org/10.1007/s10311-021-01285-w |journal=Environmental Chemistry Letters |language=en |volume=19 |issue=6 |pages=4063–4073 |doi=10.1007/s10311-021-01285-w |issn=1610-3661 |pmc=8302971 |pmid=34335128 |bibcode=2021EnvCL..19.4063H |access-date=2022-04-03 |archive-date=2023-07-30 |archive-url=https://web.archive.org/web/20230730160551/https://link.springer.com/article/10.1007/s10311-021-01285-w |url-status=live }}</ref> During the period 1940 to 2015, the mean air temperature increased by 2.24&nbsp;°C.<ref>{{Cite journal |last1=Han |first1=Jie |last2=Dai |first2=Han |last3=Gu |first3=Zhaolin |date=2021-12-01 |title=Sandstorms and desertification in Mongolia, an example of future climate events: a review |url=https://doi.org/10.1007/s10311-021-01285-w |journal=Environmental Chemistry Letters |language=en |volume=19 |issue=6 |pages=4063–4073 |doi=10.1007/s10311-021-01285-w |issn=1610-3661 |pmc=8302971 |pmid=34335128|bibcode=2021EnvCL..19.4063H }}</ref> The warmest ten-year period was during the latest decade to 2021. Precipitation has decreased by 7% over this period resulting in increased arid conditions throughout Mongolia. The Gobi desert continues to expand northward, with over 70% of Mongolia's land degraded through overgrazing, deforestation, and climate change.<ref>[https://www.adb.org/sites/default/files/publication/31145/making-grasslands-sustainable-mongolia.pdf Making Grasslands Sustainable in Mongolia] adb.org</ref> In addition, the Mongolia government has listed [[Wildfire|forest fires]], [[blight]]s, unsustainable [[forestry]] and [[mining]] activities as leading causes of desertification in the country.<ref>[https://wedocs.unep.org/bitstream/handle/20.500.11822/8918/-Report%20on%20the%20state%20of%20the%20environment%20of%20Mongolia%20(2008-2010)-2011Report-State-of-environment-Mongolia.pdf?sequence=3&isAllowed=y#:~:text=The%20Report%20of%20State%20of,damaged%20by%20mining%20activities%20are Report] unep.org</ref> The transition from [[sheep]] to [[goat]] farming in order to meet export demands for [[cashmere wool]] has caused degradation of grazing lands. Compared to sheep, goats do more damage to grazing lands by eating roots and flowers.<ref>{{Citation|last1=Dorj|first1=O.|title=Mongolia: Country Features, the Main Causes of Desertification and Remediation Efforts|date=2013|work=Combating Desertification in Asia, Africa and the Middle East|pages=217–229|editor-last=Heshmati|editor-first=G. Ali|place=Dordrecht|publisher=Springer Netherlands|language=en|doi=10.1007/978-94-007-6652-5_11|isbn=978-94-007-6651-8|last2=Enkhbold|first2=M.|last3=Lkhamyanjin|first3=S.|last4=Mijiddorj|first4=Kh.|last5=Nosmoo|first5=A.|last6=Puntsagnamil|first6=M.|last7=Sainjargal|first7=U.|editor2-last=Squires|editor2-first=Victor R.}}</ref>▼
 
{{excerpt|Gobi Desert#Desertification}}▼
 
===South America===▼
[[South America]] is another area vulnerable by desertification, as 25% of the land is classified as drylands<ref>{{Cite web |title=Soil Degradation Threatens Nutrition in Latin America - World |url=https://reliefweb.int/report/world/soil-degradation-threatens-nutrition-latin-america |access-date=2022-04-03 |website=ReliefWeb |date=16 June 2016 |language=en |archive-date=2022-04-03 |archive-url=https://web.archive.org/web/20220403121753/https://reliefweb.int/report/world/soil-degradation-threatens-nutrition-latin-america |url-status=live }}</ref> and over 68% of the land area has undergone soil erosion as a result of deforestation and overgrazing.<ref name=":0">{{Cite web |date=2018-06-15 |title=Why We Should Invest in Land Management in Latin America |url=https://www.nrdc.org/bio/carolina-herrera/why-we-should-invest-land-management-latin-america |access-date=2023-09-25 |website=www.nrdc.org |language=en}}</ref> 27 to 43% of the land areas in Bolivia, Chile, Ecuador and Peru are at risk due to desertification. In Argentina, Mexico and Paraguay, greater than half the land area is degraded by desertification and cannot be used for agriculture. In Central America, drought has caused increased unemployment and decreased food security - also causing migration of people. Similar impacts have been seen in rural parts of Mexico where about 1,000 square kms of land have been lost yearly due to desertification.<ref name=":0" /> In [[Argentina]], desertification has the potential to disrupt the nation's food supply.<ref>{{cite journal |last1=Torres |first1=Laura |last2=Abraham |first2=Elena M. |last3=Rubio |first3=Clara |last4=Barbero-Sierra |first4=Celia |last5=Ruiz-Pérez |first5=Manuel |title=Desertification Research in Argentina |journal=Land Degradation & Development |volume=26 |issue=5 |pages=433–440 |doi=10.1002/ldr.2392 |date=7 July 2015|bibcode=2015LDeDe..26..433T |hdl=11336/48401 |s2cid=129476957 |hdl-access=free }}</ref>▼
 
==Causes==
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=== Natural variations ===
Scientists agree that the existence of a desert in the place where the Sahara desert is now located is due to natural variations in [[Solar irradiance|solar insolation]] due to [[Axial precession|orbital precession]] of the Earth.<ref>{{Cite journal |last1=Tierney |first1=Jessica E. |last2=Pausata |first2=Francesco S. R. |last3=deMenocal |first3=Peter B. |date=2017-01-06 |title=Rainfall regimes of the Green Sahara |journal=Science Advances |language=en |volume=3 |issue=1 |pages=e1601503 |bibcode=2017SciA....3E1503T |doi=10.1126/sciadv.1601503 |issn=2375-2548 |pmc=5242556 |pmid=28116352}}</ref> Such variations influence the strength of the West African Monsoon, inducing feedback in vegetation and dust emission that amplify the cycle of wet and dry Sahara climate.<ref>{{Cite journal |last1=Pausata |first1=Francesco S. R. |last2=Messori |first2=Gabriele |last3=Zhang |first3=Qiong |date=2016-01-15 |title=Impacts of dust reduction on the northward expansion of the African monsoon during the Green Sahara period |journal=Earth and Planetary Science Letters |language=en |volume=434 |pages=298–307 |bibcode=2016E&PSL.434..298P |doi=10.1016/j.epsl.2015.11.049 |issn=0012-821X |doi-access=free}}</ref> There is also a suggestion the transition of the Sahara from savanna to desert during the mid-[[Holocene]] was partially due to overgrazing by the cattle of the local population.<ref name="Humans as Agents in the Termination of the African Humid Period">{{cite journal |last1=K. Wright |first1=David |last2=Rull |first2=Valenti |last3=Roberts |first3=Richard |last4=Marchant |first4=Rob |last5=Gil-Romera |first5=Graciela |date=26 January 2017 |title=Humans as Agents in the Termination of the African Humid Period |journal=Frontiers in Earth Science |volume=5 |pages=4 |bibcode=2017FrEaS...5....4W |doi=10.3389/feart.2017.00004 |doi-access=free}}</ref>
 
=== Climate change ===
{{See also|Effects of climate change on the water cycle|Effects of climate change on biomes}}
 
Research into desertification is complex, and there is no single metric which can define all aspects. However, more intense climate change is still expected to increase the current extent of drylands on the Earth's continents: from 38% in late 20th century to 50% or 56% by the end of the century, under the "moderate" and high-warming [[Representative Concentration Pathway|Representative Concentration Pathways]] 4.5 and 8.5. Most of the expansion will be seen over regions such as "southwest North America, the northern fringe of Africa, southern Africa, and Australia".<ref name=":52">{{Cite web |date=2019-08-06 |title=Explainer: Desertification and the role of climate change |url=https://www.carbonbrief.org/explainer-desertification-and-the-role-of-climate-change |url-status=live |archive-url=https://web.archive.org/web/20220210001559/https://www.carbonbrief.org/explainer-desertification-and-the-role-of-climate-change |archive-date=2022-02-10 |access-date=2019-10-22 |website=Carbon Brief |language=en}}</ref>
 
Drylands cover 41% of the earth’s land surface and include 45% of the world’s agricultural land.<ref name="Burrell">{{Cite journal |last1=Burrell |first1=A. L. |last2=Evans |first2=J. P. |last3=De Kauwe |first3=M. G. |date=2020 |title=Anthropogenic climate change has driven over 5 million km2 of drylands towards desertification |journal=Nature Communications |language=en |volume=11 |issue=1 |doi=10.1038/s41467-020-17710-7 |issn=2041-1723 |pmc=7395722 |pmid=32737311 |doi-access=free}} [[File:CC-BY icon.svg|50px]] Text was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License]</ref> These regions are among the most vulnerable ecosystems to [[Climate change|anthropogenic climate]] and [[land use change]] and are under threat of desertification. An observation-based attribution study of desertification was carried out in 2020 which accounted for climate change, [[Climate variability and change|climate variability]], [[CO2 fertilization effect|CO<sub>2</sub> fertilization]] as well as both the gradual and rapid ecosystem changes caused by land use.<ref name="Burrell" /> The study found that, between 1982 and 2015, 6% of the world’s drylands underwent desertification driven by unsustainable land use practices compounded by anthropogenic climate change. Despite an average [[global greening]], anthropogenic climate change has degraded 12.6% (5.43 million km<sup>2</sup>) of drylands, contributing to desertification and affecting 213 million people, 93% of who live in [[Developing country|developing economies]].<ref name="Burrell" />
 
== Effects ==
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=== Food insecurity ===
Global [[food security]] is being threatened by desertification. The more that [[Population growth|population grows]], the more food that has to be grown. The agricultural business is being displaced from one country to another. For example, Europe on average imports over 50% of its food. Meanwhile, 44% of agricultural land is located in dry lands and it supplies 60% of the world's food production. Desertification is decreasing the amount of sustainable land for agricultural uses but demands are continuously growing. In the near future, the demands will overcome the supply.<ref>{{Cite web |title=WAD {{!}} World Atlas of Desertification |url=https://wad.jrc.ec.europa.eu/globalagriculture |url-status=live |archive-url=https://web.archive.org/web/20191209170553/https://wad.jrc.ec.europa.eu/globalagriculture |archive-date=2019-12-09 |access-date=2019-11-19 |website=wad.jrc.ec.europa.eu}}</ref> The violent [[herder–farmer conflicts in Nigeria]], [[Sudanese nomadic conflicts|Sudan]], [[March 2019 attacks against Fulani herders|Mali]] and other countries in the Sahel region have been exacerbated by [[climate change]], [[land degradation]] and [[population growth]].<ref>{{cite magazine |date=28 June 2018 |title=How Climate Change Is Spurring Land Conflict in Nigeria |url=http://time.com/5324712/climate-change-nigeria/ |magazine=Time}}</ref><ref>{{cite news |date=22 January 2019 |title=The battle on the frontline of climate change in Mali |work=BBC News |url=https://www.bbc.com/news/the-reporters-46921487 |url-status=live |access-date=18 December 2021 |archive-url=https://web.archive.org/web/20211009175946/https://www.bbc.com/news/the-reporters-46921487 |archive-date=9 October 2021}}</ref><ref>{{cite news |date=6 August 2018 |title=Farmer-Herder Conflicts on the Rise in Africa |publisher=ReliefWeb |url=https://reliefweb.int/report/world/farmer-herder-conflicts-rise-africa |url-status=live |access-date=18 December 2021 |archive-url=https://web.archive.org/web/20210417045057/https://reliefweb.int/report/world/farmer-herder-conflicts-rise-africa |archive-date=17 April 2021}}</ref>
 
=== Vegetation patterning ===
As the desertification takes place, the landscape may progress through different stages and continuously transform in appearance. On gradually sloped terrain, desertification can create increasingly larger empty spaces over a large strip of land, a phenomenon known as "[[Tiger bush|brousse tigrée]]". A mathematical model of this phenomenon proposed by C. Klausmeier attributes this patterning to dynamics in plant-water interaction.<ref>{{cite journal |last=Klausmeier |first=Christopher |year=1999 |title=Regular and irregular patterns in semiarid vegetation |journal=Science |volume=284 |issue=5421 |pages=1826–1828 |doi=10.1126/science.284.5421.1826 |pmid=10364553}}</ref> One outcome of this observation suggests an optimal planting strategy for agriculture in arid environments.<ref>{{cite web |last=(www.dw.com) |first=Deutsche Welle |title=Grid of straw squares turns Chinese sand to soil – Environment – DW.COM – 23.06.2011 |url=http://www.dw.de/dw/article/0,,15182754,00.html |url-status=live |archive-url=https://web.archive.org/web/20200612123117/https://www.dw.com/en/grid-of-straw-squares-turns-chinese-sand-to-soil/a-15182754 |archive-date=12 June 2020 |access-date=21 June 2016}}</ref>
 
=== Increasing poverty ===
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Desertification often causes rural lands to become unable to support the same sized populations that previously lived there. This results in mass [[human migration|migrations]] out of rural areas and into urban areas particularly in Africa creating unemployment and [[slum]]s.<ref>{{cite book|author=Pasternak, Dov|author2=Schlissel, Arnold|title=Combating desertification with plants|publisher=Springer|year=2001|isbn=978-0-306-46632-8|page=20|url=https://books.google.com/books?id=B-i8-DPf6xgC&pg=PA20|access-date=2016-05-16|archive-date=2023-07-30|archive-url=https://web.archive.org/web/20230730161050/https://books.google.com/books?id=B-i8-DPf6xgC&pg=PA20|url-status=live}}</ref><ref>{{cite book|author=Briassoulis, Helen|title=Policy integration for complex environmental problems: the example of Mediterranean desertification|publisher=Ashgate Publishing|year=2005|isbn=978-0-7546-4243-5|page=161|url=https://books.google.com/books?id=CpYnV45hVRsC&pg=PA161|access-date=2016-05-16|archive-date=2023-07-30|archive-url=https://web.archive.org/web/20230730161052/https://books.google.com/books?id=CpYnV45hVRsC&pg=PA161|url-status=live}}</ref> The number of these [[Environmental migrant|environmental refugees]] grows every year, with projections for sub-Saharan Africa showing a probable increase from 14 million in 2010 to nearly 200 million by 2050. This presents a future crisis for the region, as neighboring nations do not always have the ability to support large populations of refugees.<ref>{{cite journal |last1=Myers |first1=Norman |date=29 April 2002 |title=Environmental refugees: a growing phenomenon of the 21st century |journal=Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences |volume=357 |issue=1420 |pages=609–613 |doi=10.1098/rstb.2001.0953 |pmc=1692964 |pmid=12028796}}</ref><ref>{{cite journal |last1=Epule |first1=Terence Epule |last2=Peng |first2=Changhui |last3=Lepage |first3=Laurent |date=5 February 2014 |title=Environmental refugees in sub-Saharan Africa: a review of perspectives on the trends, causes, challenges and way forward |journal=GeoJournal |volume=80 |pages=79–92 |doi=10.1007/s10708-014-9528-z |s2cid=154503204}}</ref>
 
In [[Mongolia]], the land is 90% fragile dry land, which causes many herders to migrate to the city for work. With very limited resources, the herders that stay on the dry land graze very carefully in order to preserve the land. With the increasing population of Mongolia it is very difficult to stay a herder for long.<ref>{{Cite web |date=2018-08-01 |title=Mongolia's nomadic way of life under threat |url=https://gulfnews.com/lifestyle/mongolias-nomadic-way-of-life-under-threat-1.2259998 |access-date=2023-10-04 |website=gulfnews.com |language=en}}</ref>
 
Agriculture is a main source of income for many desert communities. The increase in desertification in these regions has degraded the land to such an extent where people can no longer productively farm and make a profit. This has negatively impacted the economy and increased poverty rates.<ref>{{Cite journal|last1=Stringer|first1=Lindsay C.|last2=Dyer|first2=Jen C.|last3=Reed|first3=Mark S.|last4=Dougill|first4=Andrew J.|last5=Twyman|first5=Chasca|last6=Mkwambisi|first6=David|title=Adaptations to climate change, drought and desertification: local insights to enhance policy in southern Africa|journal=Environmental Science & Policy|volume=12|issue=7|pages=748–765|doi=10.1016/j.envsci.2009.04.002|year=2009|bibcode=2009ESPol..12..748S }}</ref>
 
There is, however, increased global advocacy e.g. the UN [[Sustainable Development Goal 15|SDG 15]]<ref>{{Cite web |title=Goal 15 targets |url=https://www.undp.org/content/undp/en/home/sustainable-development-goals/goal-15-life-on-land/targets.html |url-status=dead |archive-url=https://web.archive.org/web/20170904001634/https://www.undp.org/content/undp/en/home/sustainable-development-goals/goal-15-life-on-land/targets.html |archive-date=2017-09-04 |access-date=2020-09-24 |website=UNDP |language=en}}</ref> to combat desertification and restore affected lands.
 
▲==Geographic areas affected==
==Countermeasures{{anchor|Countermeasures_and_prevention}}==▼
▲[[Drylands]] occupy approximately 40–41% of Earth's land area and are home to more than 2 &nbsp;billion people.<ref name=":4">{{Cite book |title=Governing global desertification: linking environmental degradation, poverty and participation |date=2006 |publisher=Ashgate [u.a.] |isbn=978-0-7546-4359-3 |editor-last=Johnson |editor-first=Pierre-Marc |series=Global environmental governance series |location=Aldershot |editor-last2=Johnson |editor-first2=Pierre Marc}}</ref><ref name=":5">[https://unemg.org/2018/images/emgdocs/publications/Global_Drylands_Full_Report.pdf Global Drylands Report] unemg.org 2018</ref> It has been estimated that some 10–20% of drylands are already degraded, the total area affected by desertification being between 6 and 12 million square kilometers, that about 1–6% of the inhabitants of drylands live in desertified areas, and that a billion people are under threat from further desertification.<ref name="holtz">{{cite web |date=10 October 2017 |title=UNCCD: Impact and role of drylands |url=https://www.unccd.int/un-decade-deserts-and-fight-against-desertification-impact-and-role-drylands|title=UNCCD: Impact and role of drylands|date=10 October 2017|website=UNCCD|accessurl-datestatus=7dead November 2019|archive-date=7 November 2019|archive-url=https://web.archive.org/web/20191107121026/https://www.unccd.int/un-decade-deserts-and-fight-against-desertification-impact-and-role-drylands |urlarchive-statusdate=dead7 November 2019 |access-date=7 November 2019 |website=UNCCD}}</ref><ref>{{cite book |author=World Bank |url=https://books.google.com/books?id=XxBrq6hTs_UC&pg=PA454 |title=Gender in agriculture sourcebook |publisher=World Bank Publications |year=2009 |isbn=978-0-8213-7587-7 |page=454|url=https://books.google.com/books?id=XxBrq6hTs_UC&pg=PA454 |access-date=2016-05-16|archive-date=2023-07-30 |archive-url=https://web.archive.org/web/20230730160546/https://books.google.com/books?id=XxBrq6hTs_UC&pg=PA454 |archive-date=2023-07-30 |url-status=live}}</ref>
 
▲===Sahel===
▲{{Further|Sahel#Desertification and soil loss}}
 
▲The impact of climate change and human activities on desertification are exemplified in the [[Sahel]] region of Africa. The region is characterized by a dry hot climate, high temperatures and low rainfall (100–600&nbsp;mm per year).<ref>{{Cite journal |last=Nicholson |first=Sharon E. |date=2013-02-17 |title=The West African Sahel: A Review of Recent Studies on the Rainfall Regime and Its Interannual Variability |journal=International Scholarly Research Notices |language=en |volume=2013 |pages=e453521 |doi=10.1155/2013/453521 |doi-access=free }}</ref> So, droughts are the rule in the Sahel region.<ref>{{Cite web|url=http://earthobservatory.nasa.gov/Features/Desertification/desertification2.php|title=Defining Desertification : Feature Articles|last=Riebeek |first=Holli |date=2007-01-03 |websitetitle=Defining Desertification : Feature Articles |url=http://earthobservatory.nasa.gov/Features/Desertification/desertification2.php |accessurl-datestatus=2016-11-30|archive-date=2016-12-01live |archive-url=https://web.archive.org/web/20161201211259/http://earthobservatory.nasa.gov/Features/Desertification/desertification2.php |urlarchive-statusdate=live2016-12-01 |access-date=2016-11-30 |website=earthobservatory.nasa.gov}}</ref> The Sahel has lost approximately 650,000&nbsp;km<sup>2</sup> of its productive agricultural land over the past 50 years;<ref>[https://www.thegeographeronline.net/uploads/2/6/6/2/26629356/a116_sahel.pdf Environmental issues in the Sahel] Geo Factsheet</ref> the propagation of desertification in this area is considerable.<ref>{{cite journal |last1=Nicholson |first1=S. E. |last2=Tucker |first2=C. J. |last3=Ba |first3=M. B. |date=1 May 1998 |title=Desertification, Drought, and Surface Vegetation: An Example from the West African Sahel |journal=Bulletin of the American Meteorological Society |date=1 May 1998 |volume=79 |issue=5 |pages=815–830 |bibcode=1998BAMS...79..815N |doi=10.1175/1520-0477(1998)079<0815:DDASVA>2.0.CO;2 |bibcode=1998BAMS...79..815N |doi-access=free }}</ref><ref>{{Cite web |title=Land Resource Stresses and Desertification in Africa |url=https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/use/?cid=nrcs142p2_054025|access-date=24 November 2020|website=United States Department of Agriculture|archiveurl-datestatus=1 Aprildead 2022|archive-url=https://web.archive.org/web/20220401055308/https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/use/?cid=nrcs142p2_054025 |urlarchive-statusdate=dead1 April 2022 |access-date=24 November 2020 |website=United States Department of Agriculture}}</ref>
▲[[File:Village Telly in Mali.jpg|thumb|[[Sahel]] region of Mali]]
▲The climate of the Sahara has undergone enormous variations over the last few hundred thousand years,<ref name="Lakes">{{Cite journal |author1=Kevin White |author2=David J. Mattingly |year=2006 |title=Ancient Lakes of the Sahara | journal=American Scientist | volume=94 | yearissue=20061 | pages= 58–65 |author1=Kevin White |author2=David J. Mattingly | issue=1 | doi=10.1511/2006.57.983}}</ref> oscillating between wet (grassland) and dry (desert) every 20,000 years<ref>{{cite news |author=Jennifer Chu |date=January 2, 2019 |title=A "pacemaker" for North African climate |url=http://news.mit.edu/2019/study-regulating-north-african-climate-0102 |title=A "pacemaker" for North African climate |author=Jennifer Chu |date=January 2, 2019 |publisher=MIT News |accessurl-datestatus=January 20, 2020 |archive-date=January 15, 2022live |archive-url=https://web.archive.org/web/20220115093627/https://news.mit.edu/2019/study-regulating-north-african-climate-0102 |urlarchive-statusdate=liveJanuary 15, 2022 |access-date=January 20, 2020 |publisher=MIT News}}</ref> (a phenomenon believed to be caused by long-term changes in the [[North African climate cycle]] that alters the path of the [[North African Monsoon]], caused by an approximately 40,000-year cycle in which the [[axial tilt]] of the earth changes between 22° and 24.5°).<ref name="ReferenceA">{{cite book |last1=Houérou |first1=Henry N.|title=Bioclimatology and Biogeography of Africa|publisher=Springer Science & Business Media|isbn=978-3-540-85192-9|url=https://books.google.com/books?id=_Rvs7NkfeLEC&q=Sahara+rainfall+virtually+zero&pg=PA16 |languagetitle=enBioclimatology and Biogeography of Africa |date=2008-12-10 |publisher=Springer Science & Business Media |isbn=978-3-540-85192-9 |language=en |access-date=2020-12-11|archive-date=2023-07-30 |archive-url=https://web.archive.org/web/20230730160547/https://books.google.com/books?id=_Rvs7NkfeLEC&q=Sahara+rainfall+virtually+zero&pg=PA16 |archive-date=2023-07-30 |url-status=live}}</ref> Some statistics have shown that, since 1900, the Sahara has expanded by 250&nbsp;km to the south over a stretch of land from west to east 6,000&nbsp;km long.<ref>{{cite web |author=Christian Bouquet |date=December 2017 |title=Le Sahara entre ses deux rives. Éléments de délimitation par la géohistoire d'un espace de contraintes |websiteurl=Géoconfluenceshttp://geoconfluences.ens-lyon.fr/informations-scientifiques/dossiers-regionaux/afrique-dynamiques-regionales/articles-scientifiques/sahara-entre-deux-rives |dateurl-status=Decemberlive 2017|archive-url=https://web.archive.org/web/20220210001607/http://geoconfluences.ens-lyon.fr/informations-scientifiques/dossiers-regionaux/afrique-dynamiques-regionales/articles-scientifiques/sahara-entre-deux-rives |archive-date=2022-02-10 |access-date=2018-01-25 |website=Géoconfluences |quote=Mais il aurait progressé de 250 km vers le sud depuis 1900 (Mainguet, 2003), et dépasserait donc 9 millions de km² soit 30 % de la superficie totale du continent africain.|access-date=2018-01-25|archive-date=2022-02-10|archive-url=https://web.archive.org/web/20220210001607/http://geoconfluences.ens-lyon.fr/informations-scientifiques/dossiers-regionaux/afrique-dynamiques-regionales/articles-scientifiques/sahara-entre-deux-rives|url-status=live}}</ref>
 
▲[[Lake Chad]], located in the Sahel region, has undergone desiccation due to water withdrawal for irrigation and decrease in rainfall.<ref>{{cite journal |last1=Okpara |first1=Uche T. |last2=Stringer |first2=Lindsay C. |last3=Dougill |first3=Andrew J. |date=November 2016 |title=Lake drying and livelihood dynamics in Lake Chad: Unravelling the mechanisms, contexts and responses |journal=Ambio |date=November 2016 |volume=45 |issue=7 |pages=781–795 |bibcode=2016Ambio..45..781O |doi=10.1007/s13280-016-0805-6 |pmid=27371137 |pmc=5055484 |bibcodepmid=2016Ambio..45..781O 27371137}}</ref> The lake has shrunk by over 90% since 1987, displacing millions of inhabitants.<ref>{{Cite web |last=Jiang |first=Ingrid |date=2022-08-12 |title=A Remarkable Size Shrinking in Lake Chad |url=https://storymaps.arcgis.com/stories/e63a90f8552d4e5f98f4c56a56c06f9d |access-date=2023-09-22 |website=ArcGIS StoryMaps |language=en-ca}}</ref> Recent efforts have managed to make some progress toward its restoration, but it is still considered to be at risk of disappearing entirely.<ref name="Remote sensing appraisal of Lake Ch">{{cite journal |last1=Onamuti |first1=Olapeju Y. |last2=Okogbue |first2=Emmanuel C. |last3=Orimoloye |first3=Israel R. |date=8 November 2017 |title=Remote sensing appraisal of Lake Chad shrinkage connotes severe impacts on green economics and socio-economics of the catchment area |journal=Royal Society Open Science |volume=4 |issue=11 |pages=171120 |doi=10.1098/rsos.171120 |pmc=5717671 |pmid=29291097}}</ref>
 
▲To limit desertification, the [[Great Green Wall (Africa)]] initiative was started in 2007 involving the planting of vegetation along a stretch of 7,775 kms&nbsp;km, 15 kms&nbsp;km wide, involving 22 countries to 2030.<ref>{{Cite web |title=Great Green Wall Initiative |url=https://www.unccd.int/our-work/ggwi |access-date=2023-09-22 |website=UNCCD |language=en}}</ref> The purpose of this mammoth planting initiative is to enhance retention of water in the ground following the seasonal rainfall, thus promoting land rehabilitation and future agriculture. [[Senegal]] has already contributed to the project by planting 50,000 acres of trees. It is said to have improved land quality and caused an increase in economic opportunity in the region.<ref>{{cite web | url=https://education.nationalgeographic.org/resource/great-green-wall/ | title=The Great Green Wall &#124; National Geographic Society | access-dateurl=2022https://education.nationalgeographic.org/resource/great-12green-22wall/ | archiveurl-datestatus=2022-12-22live | archive-url=https://web.archive.org/web/20221222164123/https://education.nationalgeographic.org/resource/great-green-wall/ | urlarchive-statusdate=live2022-12-22 |access-date=2022-12-22}}</ref>
 
▲===Gobi Desert and Mongolia===
▲{{See also|Environmental issues in Mongolia#Desertification}}
 
▲Another major area that is being impacted by desertification is the [[Gobi Desert]] located in Northern China and Southern Mongolia. The Gobi Desert is the fastest expanding desert on Earth, as it transforms over {{convert|3600|km2|sqmi|abbr=off}} of grassland into wasteland annually.<ref>{{Cite web |last=Rechtschaffen |first=Daniel |title=How China's Growing Deserts Are Choking The Country |url=https://www.forbes.com/sites/danielrechtschaffen/2017/09/18/how-chinas-growing-deserts-are-choking-the-country/ |accessurl-datestatus=2022-08-28 |website=Forbes |language=en |archive-date=2022-02-16live |archive-url=https://web.archive.org/web/20220216110308/https://www.forbes.com/sites/danielrechtschaffen/2017/09/18/how-chinas-growing-deserts-are-choking-the-country/ |urlarchive-statusdate=live2022-02-16 |access-date=2022-08-28 |website=Forbes |language=en}}</ref> Although the Gobi Desert itself is still a distance away from [[Beijing]], reports from field studies state there are large sand dunes forming only 70&nbsp;km (43.5&nbsp;mi) outside the city.<ref>{{cite report|last=Welker|first=Lauren |url=http://www.geo.utexas.edu/courses/371c/project/2009/Welker_Desertification.pdf |title=The Desertification of the Gobi Desert and Its Effect on Beijing |last=Welker |first=Lauren |date=2009 |publisher=University of Texas-Austin School of Geosciences |archive-url=https://web.archive.org/web/20140124101958/http://www.geo.utexas.edu/courses/371c/project/2009/Welker_Desertification.pdf |archive-date=2014-01-24 |url-status=live |title=The Desertification of the Gobi Desert and Its Effect on Beijing |date=2009 |type=Unpublished manuscript |publisher=University of Texas-Austin School of Geosciences}}</ref><ref>{{Cite web |date=2020-03-25 |title=Gobi Desert: A Complete Guide to East Asia's Largest Desert |url=https://www.youngpioneertours.com/gobi-desert-guide/ |accessurl-datestatus=2022-04-03 |website=Young Pioneer Tours |language=en |archive-date=2023-07-30live |archive-url=https://web.archive.org/web/20230730160548/https://www.youngpioneertours.com/gobi-desert-guide/ |urlarchive-statusdate=live2023-07-30 |access-date=2022-04-03 |website=Young Pioneer Tours |language=en}}</ref>
 
▲In [[Mongolia]], around 90% of grassland is considered [[vulnerability|vulnerable]] to desertification by the UN. An estimated 13% of desertification in Mongolia is caused by natural factors; the rest is due to human influence particularly overgrazing and increased erosion of soils in cultivated areas.<ref>{{Cite web |title=What Is Desertification and How Does It Impact Mongolia? |url=https://breathemongolia.org/en/news-article/desertification-impact-mongolia/ |accessurl-datestatus=2022-04-03 |website=Breathe Mongolia – English |language=en-US |archive-date=2022-04-01live |archive-url=https://web.archive.org/web/20220401180828/https://breathemongolia.org/en/news-article/desertification-impact-mongolia |urlarchive-statusdate=live2022-04-01 |access-date=2022-04-03 |website=Breathe Mongolia – English |language=en-US}}</ref><ref>{{Cite journal |last1=Han |first1=Jie |last2=Dai |first2=Han |last3=Gu |first3=Zhaolin |date=2021-12-01 |title=Sandstorms and desertification in Mongolia, an example of future climate events: a review |url=https://doi.org/10.1007/s10311-021-01285-w |url-status=live |journal=Environmental Chemistry Letters |language=en |volume=19 |issue=6 |pages=4063–4073 |bibcode=2021EnvCL..19.4063H |doi=10.1007/s10311-021-01285-w |issn=1610-3661 |pmc=8302971 |pmid=34335128 |bibcode=2021EnvCL..19.4063H |access-date=2022-04-03 |archive-date=2023-07-30 |archive-url=https://web.archive.org/web/20230730160551/https://link.springer.com/article/10.1007/s10311-021-01285-w |urlarchive-statusdate=live2023-07-30 |access-date=2022-04-03}}</ref> During the period 1940 to 2015, the mean air temperature increased by 2.24&nbsp;°C.<ref>{{Cite journal |last1=Han |first1=Jie |last2=Dai |first2=Han |last3=Gu |first3=Zhaolin |date=2021-12-01 |title=Sandstorms and desertification in Mongolia, an example of future climate events: a review |url=https://doi.org/10.1007/s10311-021-01285-w |journal=Environmental Chemistry Letters |language=en |volume=19 |issue=6 |pages=4063–4073 |bibcode=2021EnvCL..19.4063H |doi=10.1007/s10311-021-01285-w |issn=1610-3661 |pmc=8302971 |pmid=34335128|bibcode=2021EnvCL..19.4063H }}</ref> The warmest ten-year period was during the latest decade to 2021. Precipitation has decreased by 7% over this period resulting in increased arid conditions throughout Mongolia. The Gobi desert continues to expand northward, with over 70% of Mongolia's land degraded through overgrazing, deforestation, and climate change.<ref>[https://www.adb.org/sites/default/files/publication/31145/making-grasslands-sustainable-mongolia.pdf Making Grasslands Sustainable in Mongolia] adb.org</ref> In addition, the Mongolia government has listed [[Wildfire|forest fires]], [[blight]]s, unsustainable [[forestry]] and [[mining]] activities as leading causes of desertification in the country.<ref>[https://wedocs.unep.org/bitstream/handle/20.500.11822/8918/-Report%20on%20the%20state%20of%20the%20environment%20of%20Mongolia%20(2008-2010)-2011Report-State-of-environment-Mongolia.pdf?sequence=3&isAllowed=y#:~:text=The%20Report%20of%20State%20of,damaged%20by%20mining%20activities%20are Report] unep.org</ref> The transition from [[sheep]] to [[goat]] farming in order to meet export demands for [[cashmere wool]] has caused degradation of grazing lands. Compared to sheep, goats do more damage to grazing lands by eating roots and flowers.<ref>{{Citation |last1=Dorj |first1=O. |title=Mongolia: Country Features, the Main Causes of Desertification and Remediation Efforts |date=2013 |work=Combating Desertification in Asia, Africa and the Middle East |pages=217–229 |editor-last=Heshmati |editor-first=G. Ali |place=Dordrecht |publisher=Springer Netherlands |language=en |doi=10.1007/978-94-007-6652-5_11 |isbn=978-94-007-6651-8 |last2=Enkhbold |first2=M. |last3=Lkhamyanjin |first3=S. |last4=Mijiddorj |first4=Kh. |last5=Nosmoo |first5=A. |last6=Puntsagnamil |first6=M. |last7=Sainjargal |first7=U. |editor2-last=Squires |editor2-first=Victor R.}}</ref>
 
▲{{excerpt|Gobi Desert#Desertification}}
 
▲===South America===
▲[[South America]] is another area vulnerable by desertification, as 25% of the land is classified as drylands<ref>{{Cite web |date=16 June 2016 |title=Soil Degradation Threatens Nutrition in Latin America - World |url=https://reliefweb.int/report/world/soil-degradation-threatens-nutrition-latin-america |accessurl-datestatus=2022-04-03 |website=ReliefWeb |date=16 June 2016 |language=en |archive-date=2022-04-03live |archive-url=https://web.archive.org/web/20220403121753/https://reliefweb.int/report/world/soil-degradation-threatens-nutrition-latin-america |urlarchive-statusdate=live2022-04-03 |access-date=2022-04-03 |website=ReliefWeb |language=en}}</ref> and over 68% of the land area has undergone soil erosion as a result of deforestation and overgrazing.<ref name=":0">{{Cite web |date=2018-06-15 |title=Why We Should Invest in Land Management in Latin America |url=https://www.nrdc.org/bio/carolina-herrera/why-we-should-invest-land-management-latin-america |access-date=2023-09-25 |website=www.nrdc.org |language=en}}</ref> 27 to 43% of the land areas in Bolivia, Chile, Ecuador and Peru are at risk due to desertification. In Argentina, Mexico and Paraguay, greater than half the land area is degraded by desertification and cannot be used for agriculture. In Central America, drought has caused increased unemployment and decreased food security - also causing migration of people. Similar impacts have been seen in rural parts of Mexico where about 1,000 square kms&nbsp;km<sup>2</sup> of land have been lost yearly due to desertification.<ref name=":0" /> In [[Argentina]], desertification has the potential to disrupt the nation's food supply.<ref>{{cite journal |last1=Torres |first1=Laura |last2=Abraham |first2=Elena M. |last3=Rubio |first3=Clara |last4=Barbero-Sierra |first4=Celia |last5=Ruiz-Pérez |first5=Manuel |date=7 July 2015 |title=Desertification Research in Argentina |journal=Land Degradation & Development |volume=26 |issue=5 |pages=433–440 |doi=10.1002/ldr.2392 |date=7 July 2015|bibcode=2015LDeDe..26..433T |hdldoi=1133610.1002/48401ldr.2392 |s2cid=129476957 |hdl-access=free |hdl=11336/48401}}</ref>
▲==CountermeasuresReversing desertification{{anchor|Countermeasures_and_prevention}}==
{{See also|Deforestation#Control}}
[[File:Harsh Vardhan addressing at the inauguration of the United Nations Convention to Combat Desertification (UNCCD) Asia-Pacific four-day Regional Workshop, in New Delhi (1).JPG|thumb|A 2018 meeting in [[New Delhi]] inaugaratingrelated to the [[United Nations Convention to Combat Desertification]]]]
[[File:North Sahara. Anti-sand shields.jpg|thumb|Anti-sand shields in north [[Sahara]], [[Tunisia]]]]
[[File:GreeningdesertTharIndia.jpg|thumb|[[Jojoba]] plantations, such as those shown, have played a role in combating edge effects of desertification in the [[Thar Desert]], [[India]].<ref>{{cite book|last1=Pasternak|first1=D.|last2=Schlissel|first2=Arnold|title=Combating Desertification with Plants|publisher=Springer Science & Business Media|isbn=9781461513278|page=38|url=https://books.google.com/books?id=6XfgBwAAQBAJ&pg=PA38|date=2012-12-06}}</ref>]]
[[File:Saxaul planted along roads in Xinjiang near Cherchen to slow desertification.jpg|thumb|[[Saxaul]] planted along roads in Xinjiang near [[Cherchen]] to slow desertification]]
Techniques and countermeasures exist for mitigating or reversing the effects of desertification,. andFor some possess varying levels of difficulty.these For somemeasures, there are numerous barriers to their implementation. Yet for others, the solution simply requires the exercise of human reason.
 
One proposed barrier is that the costs of adopting [[sustainable agriculture|sustainable agricultural practices]] sometimes exceed the benefits for individual farmers, even while they are socially and environmentally beneficial.<ref>{{cite journal|last1=Drost|first1=Daniel|last2=Long|first2=Gilbert|last3=Wilson|first3=David|last4=Miller|first4=Bruce|last5=Campbell|first5=William|title=Barriers to Adopting Sustainable Agricultural Practices|issue=6|url=https://www.joe.org/joe/1996december/a1.php|journal=Journal of Extension|volume=34|date=1 December 1996|access-date=21 February 2017|archive-date=22 February 2017|archive-url=https://web.archive.org/web/20170222053123/https://www.joe.org/joe/1996december/a1.php|url-status=dead}}</ref> Another issue is a lack of political will, and lack of funding to support [[land reclamation]] and anti-desertification programs.<ref>{{cite book|author=Briassoulis, Helen|title=Policy integration for complex environmental problems: the example of Mediterranean desertification|publisher=Ashgate Publishing|year=2005|isbn=978-0-7546-4243-5|page=237|url=https://books.google.com/books?id=CpYnV45hVRsC&pg=PA237}}</ref>
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Desertification is recognized as a major threat to [[biodiversity]]. Some countries have developed [[biodiversity action plan]]s to counter its effects, particularly in relation to the protection of endangered [[flora]] and [[fauna]].<ref>Techniques for Desert Reclamation by Andrew S. Goudie</ref><ref>{{Cite web|url=http://www.gsafweb.org/TrusteeNews/desertdevelopmen.html|archive-url=https://web.archive.org/web/20090103172821/http://www.gsafweb.org/TrusteeNews/desertdevelopmen.html|url-status=dead|title=Desert reclamation projects|archive-date=3 January 2009}}</ref>
 
=== ReforestationImproving soil quality ===
{{Main|ReforestationSoil regeneration}}
[[Reforestation]] gets at one of the root causes of desertification and is not just a treatment of the symptoms. Environmental organizations work in places where deforestation and desertification are contributing to extreme [[poverty]]. There they focus primarily on educating the local population about the dangers of deforestation and sometimes employ them to grow seedlings, which they transfer to severely deforested areas during the rainy season.<ref>{{cite web|url=http://pubs.usgs.gov/gip/deserts/desertification/|title=Desertification|website=USGS|date=1997|access-date=2006-06-10|archive-date=2010-08-02|archive-url=https://web.archive.org/web/20100802200740/http://pubs.usgs.gov/gip/deserts/desertification/|url-status=live}}</ref> The [[Food and Agriculture Organization of the United Nations]] launched the FAO Drylands Restoration Initiative in 2012 to draw together knowledge and experience on dryland restoration.<ref>{{cite web|title=Drylands Restoration Initiative|url=http://www.fao.org/forestry/aridzone/restoration/en/|publisher=Food and Agriculture Organization of the United Nations|access-date=14 April 2016|archive-date=23 July 2016|archive-url=https://web.archive.org/web/20160723220152/http://www.fao.org/forestry/aridzone/restoration/en/|url-status=live}}</ref> In 2015, FAO published global guidelines for the restoration of degraded forests and landscapes in drylands, in collaboration with the Turkish Ministry of Forestry and Water Affairs and the Turkish Cooperation and Coordination Agency.<ref>{{cite book|title=Global guidelines for the restoration of degraded forests and landscapes in drylands|date=June 2015|publisher=Food and Agriculture Organization of the United Nations|isbn=978-92-5-108912-5|url=http://www.fao.org/3/a-i5036e.pdf |archive-url=https://web.archive.org/web/20160423203240/http://www.fao.org/3/a-i5036e.pdf |archive-date=2016-04-23 |url-status=live<!-- |access-date=June 2015 -->}}</ref>▼
 
The "[[Green Wall of China]]" is a high-profile example of one method that has been finding success in this battle with desertification.<ref>{{Cite web|title=desertification 3D environment|url=https://b2b.partcommunity.com/community/knowledge/en/detail/9815/Desertification#knowledge_article|access-date=2020-09-25|archive-date=2021-02-28|archive-url=https://web.archive.org/web/20210228141238/https://b2b.partcommunity.com/community/knowledge/en/detail/9815/Desertification#knowledge_article|url-status=live}}</ref> This wall is a much larger-scale version of what American farmers did in the 1930s to stop the great Midwest dust bowl. This plan was proposed in the late 1970s, and has become a major ecological engineering project that is not predicted to end until the year 2055. According to Chinese reports, there have been nearly 66&nbsp;billion trees planted in China's great green wall.<ref>{{Cite web| url=http://news.nationalgeographic.com/2017/04/china-great-green-wall-gobi-tengger-desertification/| title=China's 'Great Green Wall' Fights Expanding Desert| date=2017-04-21| access-date=2017-05-04| archive-date=2017-08-13| archive-url=https://web.archive.org/web/20170813110737/http://news.nationalgeographic.com/2017/04/china-great-green-wall-gobi-tengger-desertification/| url-status=dead}}</ref> The green wall of China has decreased desert land in China by an annual average of 1,980 square km.<ref>{{Cite news |url=http://www.xinhuanet.com/english/2018-05/26/c_137207841.htm |archive-url=https://web.archive.org/web/20180526094225/http://www.xinhuanet.com/english/2018-05/26/c_137207841.htm |url-status=dead |archive-date=May 26, 2018 |title=Across China: A guardian of the great green wall against China's second largest desert |last=Hui |first=Lu |date=May 26, 2018 |work=Xinghua News Agency }}</ref> The frequency of sandstorms nationwide have fallen 20% due to the green wall.<ref>{{Cite journal|last=Beiser|first=Vince|date=September 1, 2017|title=A tree grows in China: can a "Green Great Wall" stop sand from devouring the countryside?|journal=Mother Jones|volume=83|issue=4}}</ref> Due to the success that China has been finding in stopping the spread of desertification, plans are currently being made in Africa to start a "wall" along the borders of the Sahara desert as well to be financed by the United Nations Global Environment Facility trust.<ref>{{Cite journal|last=Gadzama|first=Njidda Mamadu|date=2017|title=Attenuation of the effects of desertification through sustainable development of Great Green Wall in the Sahel of Africa|journal=World Journal of Science, Technology and Sustainable Development|volume=14|issue=4|pages=279–289|doi=10.1108/WJSTSD-02-2016-0021}}</ref>▼
[[File:Great green wall map.svg|thumb|The [[Great Green Wall (Africa)|Great Green Wall]], participating countries and Sahel. In September 2020, it was reported that the GGW had covered only 4% of the planned area.<ref>{{cite news|author=Jonathan Watts|title=Africa's Great Green Wall just 4% complete halfway through schedule|url=https://www.theguardian.com/environment/2020/sep/07/africa-great-green-wall-just-4-complete-over-halfway-through-schedule|newspaper=The Guardian|date=7 September 2020|issn=0261-3077|via=www.theguardian.com|access-date=18 December 2021|archive-date=6 May 2022|archive-url=https://web.archive.org/web/20220506222825/https://www.theguardian.com/environment/2020/sep/07/africa-great-green-wall-just-4-complete-over-halfway-through-schedule|url-status=live}}</ref>]]▼
In 2007 the [[African Union]] started the [[Great Green Wall (Africa)|Great Green Wall of Africa]] project in order to combat desertification in 20 countries.<ref>{{Cite web |title=Great Green Wall{{!}}Action Against Desertification{{!}}Food and Agriculture Organization of the United Nations |url=https://www.fao.org/in-action/action-against-desertification/overview/great-green-wall/en/ |access-date=2022-02-27 |website=www.fao.org |archive-date=2022-01-27 |archive-url=https://web.archive.org/web/20220127153831/https://www.fao.org/in-action/action-against-desertification/overview/great-green-wall/en/ |url-status=live }}</ref> The wall is 8,000&nbsp;km wide, stretching across the entire width of the continent and has 8 billion dollars in support of the project. The project has restored 36{{nbsp}}million{{nbsp}}hectares of land, and by 2030 the initiative plans to restore a total of 100{{nbsp}}million{{nbsp}}hectares.<ref>{{Cite journal|last=Gadzama|first=Njidda|date=2017|title=Attenuation of the Effects of Desertification through Sustainable Development of Great Green Wall in the Sahel of Africa|journal=World Journal of Science, Technology and Sustainable Development|volume=14|issue=4|pages=279–289|doi=10.1108/WJSTSD-02-2016-0021}}</ref> The Great Green Wall has created many job opportunities for the participating countries, with over 20,000 jobs created in Nigeria alone.<ref>{{Cite web|last=United Nations Convention to Combat Desertification|date=2019|title=The Great Green Wall Initiative|url=https://www.unccd.int/actions/great-green-wall-initiative|access-date=2019-12-03|website=United Nations Convention to Combat Desertification|archive-date=2019-12-02|archive-url=https://web.archive.org/web/20191202120122/https://www.unccd.int/actions/great-green-wall-initiative|url-status=live}}</ref>▼
 
=== Soil restoration ===
Techniques focus on two aspects: provisioning of water, and [[Erosion control|fixation]] and hyper-fertilizing soil. Fixating the soil is often done through the use of [[windbreak|shelter belts]], [[woodlot]]s and [[windbreak]]s. Windbreaks are made from trees and bushes and are used to reduce [[soil erosion]] and [[evapotranspiration]].<ref>{{Cite web |title=Windbreaks - an overview {{!}} ScienceDirect Topics |url=https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/windbreaks |access-date=2022-02-27 |website=www.sciencedirect.com |archive-date=2022-02-27 |archive-url=https://web.archive.org/web/20220227003534/https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/windbreaks |url-status=live }}</ref> They were widely encouraged by development agencies from the middle of the 1980s in the [[Sahel]] area of [[Africa]].
 
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The [[Genetically modified organism|bioengineering]] of soil microbes, particularly photosynthesizers, has also been suggested and theoretically modeled as a method to protect drylands. The aim would be to enhance the existing cooperative loops between soil microbes and vegetation.<ref>{{Cite web|title=Bioengineered soil microbes may help prevent desertification|url=https://phys.org/news/2020-08-bioengineered-soil-microbes-desertification.html|access-date=2020-08-26|website=phys.org|language=en|archive-date=2020-08-27|archive-url=https://web.archive.org/web/20200827204631/https://phys.org/news/2020-08-bioengineered-soil-microbes-desertification.html|url-status=live}}</ref>
 
=== Desert reclamationgreening ===
* [[{{Main|Desert greening]]}}▼
{{See also|Afforestation}}
 
As there are many different types of deserts, there are also different types of desert reclamation [[methodologies]]. An example for this is the salt flats in the [[Rub' al Khali]] desert in [[Saudi Arabia]]. These salt flats are one of the most promising desert areas for seawater agriculture and could be revitalized without the use of freshwater or much energy.<ref>[http://www.prototype-creation.de/rethinking_landscapes.pdf Rethinking landscapes, Nicol-André Berdellé July 2011] {{Webarchive|url=https://web.archive.org/web/20160817063318/http://www.prototype-creation.de/rethinking_landscapes.pdf |date=2016-08-17 }} H2O magazine</ref>
 
[[Farmer-managed natural regeneration]] (FMNR) is another technique that has produced successful results for desert reclamation. Since 1980, this method to reforest degraded landscape has been applied with some success in Niger. This simple and low-cost method has enabled farmers to regenerate some 30,000 square kilometers in Niger. The process involves enabling native sprouting tree growth through selective pruning of shrub shoots. The residue from pruned trees can be used to provide mulching for fields thus increasing [[Soil water (retention)|soil water retention]] and reducing evaporation. Additionally, properly spaced and pruned trees can increase crop yields. The Humbo Assisted Regeneration Project which uses FMNR techniques in Ethiopia has received money from The World Bank's BioCarbon Fund, which supports projects that sequester or conserve carbon in forests or agricultural ecosystems.<ref>{{cite web |url=http://blogs.ei.columbia.edu/2011/10/18/sprouting-trees-from-the-underground-forest-a-simple-way-to-fight-desertification-and-climate-change/ |title=Sprouting Trees From the Underground Forest — A Simple Way to Fight Desertification and Climate Change – Water Matters – State of the Planet |publisher=Blogs.ei.columbia.edu |date=2011-10-18 |access-date=2012-08-11 |archive-date=2012-06-23 |archive-url=https://web.archive.org/web/20120623022554/http://blogs.ei.columbia.edu/2011/10/18/sprouting-trees-from-the-underground-forest-a-simple-way-to-fight-desertification-and-climate-change/ |url-status=live }}</ref>
 
▲[[Reforestation]] gets at one of the root causes of desertification and is not just a treatment of the symptoms. Environmental organizations work in places where deforestation and desertification are contributing to extreme [[poverty]]. There they focus primarily on educating the local population about the dangers of deforestation and sometimes employ them to grow seedlings, which they transfer to severely deforested areas during the rainy season.<ref>{{cite web|url=http://pubs.usgs.gov/gip/deserts/desertification/|title=Desertification|website=USGS|date=1997|access-date=2006-06-10|archive-date=2010-08-02|archive-url=https://web.archive.org/web/20100802200740/http://pubs.usgs.gov/gip/deserts/desertification/|url-status=live}}</ref> The [[Food and Agriculture Organization of the United Nations]] launched the FAO Drylands Restoration Initiative in 2012 to draw together knowledge and experience on dryland restoration.<ref>{{cite web |title=Drylands Restoration Initiative |url=http://www.fao.org/forestry/aridzone/restoration/en/|publisher=Food and Agriculture Organization of the United Nations|accessurl-datestatus=14live April 2016|archive-date=23 July 2016|archive-url=https://web.archive.org/web/20160723220152/http://www.fao.org/forestry/aridzone/restoration/en/ |urlarchive-statusdate=live23 July 2016 |access-date=14 April 2016 |publisher=Food and Agriculture Organization of the United Nations}}</ref> In 2015, FAO published global guidelines for the restoration of degraded forests and landscapes in drylands, in collaboration with the Turkish Ministry of Forestry and Water Affairs and the Turkish Cooperation and Coordination Agency.<ref>{{cite book |url=http://www.fao.org/3/a-i5036e.pdf |title=Global guidelines for the restoration of degraded forests and landscapes in drylands |date=June 2015 |publisher=Food and Agriculture Organization of the United Nations |isbn=978-92-5-108912-5|url=http://www.fao.org/3/a-i5036e.pdf |archive-url=https://web.archive.org/web/20160423203240/http://www.fao.org/3/a-i5036e.pdf |archive-date=2016-04-23 |url-status=live<!-- |access-date=June 2015 -->}}</ref>
===Managed grazing===▼
 
▲The "[[Green Wall of China]]" is a high-profile example of one method that has been finding success in this battle with desertification.<ref>{{Cite web |title=desertification 3D environment |url=https://b2b.partcommunity.com/community/knowledge/en/detail/9815/Desertification#knowledge_article |accessurl-datestatus=2020-09-25|archive-date=2021-02-28live |archive-url=https://web.archive.org/web/20210228141238/https://b2b.partcommunity.com/community/knowledge/en/detail/9815/Desertification#knowledge_article |urlarchive-statusdate=live2021-02-28 |access-date=2020-09-25}}</ref> This wall is a much larger-scale version of what American farmers did in the 1930s to stop the great Midwest dust bowl. This plan was proposed in the late 1970s, and has become a major ecological engineering project that is not predicted to end until the year 2055. According to Chinese reports, there have been nearly 66&nbsp;billion trees planted in China's great green wall.<ref>{{Cite web |date=2017-04-21 |title=China's 'Great Green Wall' Fights Expanding Desert |url=http://news.nationalgeographic.com/2017/04/china-great-green-wall-gobi-tengger-desertification/| title=China's 'Great Green Wall' Fights Expanding Desert| date=2017url-04-21| access-datestatus=2017-05-04|dead archive-date=2017-08-13| archive-url=https://web.archive.org/web/20170813110737/http://news.nationalgeographic.com/2017/04/china-great-green-wall-gobi-tengger-desertification/ |archive-date=2017-08-13 url|access-statusdate=dead2017-05-04}}</ref> The green wall of China has decreased desert land in China by an annual average of 1,980 square km.<ref>{{Cite news |last=Hui |first=Lu |date=May 26, 2018 |title=Across China: A guardian of the great green wall against China's second largest desert |url=http://www.xinhuanet.com/english/2018-05/26/c_137207841.htm |url-status=dead |archive-url=https://web.archive.org/web/20180526094225/http://www.xinhuanet.com/english/2018-05/26/c_137207841.htm |url-status=dead |archive-date=May 26, 2018 |title=Across China: A guardian of the great green wall against China's second largest desert |last=Hui |first=Lu |date=May 26, 2018 |work=Xinghua News Agency }}</ref> The frequency of sandstorms nationwide have fallen 20% due to the green wall.<ref>{{Cite journal |last=Beiser |first=Vince |date=September 1, 2017 |title=A tree grows in China: can a "Green Great Wall" stop sand from devouring the countryside? |journal=Mother Jones |volume=83 |issue=4}}</ref> Due to the success that China has been finding in stopping the spread of desertification, plans are currently being made in Africa to start a "wall" along the borders of the Sahara desert as well to be financed by the United Nations Global Environment Facility trust.<ref>{{Cite journal |last=Gadzama |first=Njidda Mamadu |date=2017 |title=Attenuation of the effects of desertification through sustainable development of Great Green Wall in the Sahel of Africa |journal=World Journal of Science, Technology and Sustainable Development |volume=14 |issue=4 |pages=279–289 |doi=10.1108/WJSTSD-02-2016-0021}}</ref>
Restored grasslands store CO<sub>2</sub> from the atmosphere as organic plant material. [[Grazing]] livestock, usually not left to wander, consume the grass and minimize its growth.<ref name="Tlovell">{{cite news|url=http://www.newstatesman.com/environment/2011/01/lovell-carbon-ward-climate|title=How fences could save the planet|publisher=newstatesman.com|access-date=May 5, 2013|date=January 13, 2011|archive-date=August 14, 2017|archive-url=https://web.archive.org/web/20170814221316/http://www.newstatesman.com/environment/2011/01/lovell-carbon-ward-climate|url-status=live}}</ref> A method proposed to restore grasslands uses fences with many small paddocks, moving herds from one paddock to another after a day or two in order to mimic natural grazers and allowing the grass to grow optimally.<ref name="Tlovell" /><ref>{{cite news|url=http://news.mongabay.com/2008/0221-soil_carbon_lovell_interview.html|title=Restoring soil carbon can reverse global warming, desertification and biodiversity|publisher=mongabay.com|access-date=May 5, 2013|date=February 21, 2008|url-status=dead|archive-url=https://archive.today/20130625040133/http://news.mongabay.com/2008/0221-soil_carbon_lovell_interview.html|archive-date=June 25, 2013}}</ref><ref>{{cite news|url=http://www.time.com/time/magazine/article/0,9171,1953692,00.html|archive-url=https://web.archive.org/web/20100117215802/http://www.time.com/time/magazine/article/0,9171,1953692,00.html|url-status=dead|archive-date=January 17, 2010|title=How eating grass-fed beef could help fight climate change|publisher=time.com|access-date=May 11, 2013|date=January 25, 2010|first=Lisa|last=Abend}}</ref> Proponents of managed grazing methods estimate that increasing this method could increase carbon content of the soils in the world's 3.5 billion hectares of agricultural grassland and offset nearly 12 years of CO<sub>2</sub> emissions.<ref name="Tlovell" />▼
▲[[File:Great green wall map.svg|thumb|The [[Great Green Wall (Africa)|Great Green Wall]], participating countries and Sahel. In September 2020, it was reported that the GGW had covered only 4% of the planned area.<ref>{{cite news |author=Jonathan Watts |date=7 September 2020 |title=Africa's Great Green Wall just 4% complete halfway through schedule |url=https://www.theguardian.com/environment/2020/sep/07/africa-great-green-wall-just-4-complete-over-halfway-through-schedule|newspaper=The Guardian|date=7 September 2020|issn=0261url-3077|viastatus=www.theguardian.com|access-date=18live December 2021|archive-date=6 May 2022|archive-url=https://web.archive.org/web/20220506222825/https://www.theguardian.com/environment/2020/sep/07/africa-great-green-wall-just-4-complete-over-halfway-through-schedule |urlarchive-statusdate=live6 May 2022 |access-date=18 December 2021 |newspaper=The Guardian |via=www.theguardian.com |issn=0261-3077}}</ref>]]
▲In 2007 the [[African Union]] started the [[Great Green Wall (Africa)|Great Green Wall of Africa]] project in order to combat desertification in 20 countries.<ref>{{Cite web |title=Great Green Wall{{!}}Action Against Desertification{{!}}Food and Agriculture Organization of the United Nations |url=https://www.fao.org/in-action/action-against-desertification/overview/great-green-wall/en/ |accessurl-datestatus=2022-02-27 |website=www.fao.org |archive-date=2022-01-27live |archive-url=https://web.archive.org/web/20220127153831/https://www.fao.org/in-action/action-against-desertification/overview/great-green-wall/en/ |urlarchive-statusdate=live2022-01-27 |access-date=2022-02-27 |website=www.fao.org}}</ref> The wall is 8,000&nbsp;km wide, stretching across the entire width of the continent and has 8 billion dollars in support of the project. The project has restored 36{{nbsp}}million{{nbsp}}hectares of land, and by 2030 the initiative plans to restore a total of 100{{&nbsp}};million{{nbsp}}hectares.<ref>{{Cite journal |last=Gadzama |first=Njidda |date=2017 |title=Attenuation of the Effects of Desertification through Sustainable Development of Great Green Wall in the Sahel of Africa |journal=World Journal of Science, Technology and Sustainable Development |volume=14 |issue=4 |pages=279–289 |doi=10.1108/WJSTSD-02-2016-0021}}</ref> The Great Green Wall has created many job opportunities for the participating countries, with over 20,000 jobs created in Nigeria alone.<ref>{{Cite web |last=United Nations Convention to Combat Desertification |date=2019 |title=The Great Green Wall Initiative |url=https://www.unccd.int/actions/great-green-wall-initiative |accessurl-datestatus=2019-12-03|website=Unitedlive Nations Convention to Combat Desertification|archive-date=2019-12-02|archive-url=https://web.archive.org/web/20191202120122/https://www.unccd.int/actions/great-green-wall-initiative |urlarchive-statusdate=live2019-12-02 |access-date=2019-12-03 |website=United Nations Convention to Combat Desertification}}</ref>
 
▲===ManagedBetter managed grazing===
 
▲Restored grasslands store CO<sub>2</sub> from the atmosphere as organic plant material. [[Grazing]] livestock, usually not left to wander, consume the grass and minimize its growth.<ref name="Tlovell">{{cite news|url=http://www.newstatesman.com/environment/2011/01/lovell-carbon-ward-climate|title=How fences could save the planet|publisher=newstatesman.com|access-date=May 5, 2013|date=January 13, 2011|archive-date=August 14, 2017|archive-url=https://web.archive.org/web/20170814221316/http://www.newstatesman.com/environment/2011/01/lovell-carbon-ward-climate|url-status=live}}</ref> A method proposed to restore grasslands uses fences with many small paddocks, moving herds from one paddock to another after a day or two in order to mimic natural grazers and allowing the grass to grow optimally.<ref name="Tlovell" /><ref>{{cite news|url=http://news.mongabay.com/2008/0221-soil_carbon_lovell_interview.html|title=Restoring soil carbon can reverse global warming, desertification and biodiversity|publisher=mongabay.com|access-date=May 5, 2013|date=February 21, 2008|url-status=dead|archive-url=https://archive.today/20130625040133/http://news.mongabay.com/2008/0221-soil_carbon_lovell_interview.html|archive-date=June 25, 2013}}</ref><ref>{{cite news|url=http://www.time.com/time/magazine/article/0,9171,1953692,00.html|archive-url=https://web.archive.org/web/20100117215802/http://www.time.com/time/magazine/article/0,9171,1953692,00.html|url-status=dead|archive-date=January 17, 2010|title=How eating grass-fed beef could help fight climate change|publisher=time.com|access-date=May 11, 2013|date=January 25, 2010|first=Lisa|last=Abend}}</ref> Proponents of managed grazing methods estimate that increasing this method could increase carbon content of the soils in the world's 3.5 &nbsp;billion hectares of agricultural grassland and offset nearly 12 years of CO<sub>2</sub> emissions.<ref name="Tlovell" />
 
== History ==
{{Further|Historic desertification}}
 
The world's most noted [[deserts]] have been formed by natural processes interacting over long intervals of time. During most of these times, deserts have grown and shrunk independently of human activities. Paleodeserts are large [[sand sea]]s now inactive because they are stabilized by vegetation, some extending beyond the present margins of core deserts, such as the [[Sahara]], the largest hot desert.<ref name=":1">{{Cite web |title=Desertification |url=https://pubs.usgs.gov/gip/deserts/desertification/ |access-date=2023-09-11 |website=pubs.usgs.gov}}</ref>
 
Historical evidence shows that the serious and extensive land deterioration occurring several centuries ago in arid regions had three centers: the Mediterranean, the Mesopotamian Valley, and the [[Loess Plateau]] of China, where population was dense.<ref name=":7">{{cite web |last=Dregne |first=H.E. |title=Desertification of Arid Lands |url=http://www.ciesin.columbia.edu/docs/002-193/002-193.html |url-status=live |archive-url=https://web.archive.org/web/20230428120939/http://www.ciesin.columbia.edu/docs/002-193/002-193.html |archive-date=28 April 2023 |access-date=3 December 2013 |publisher=Columbia University}}</ref>
 
The earliest known discussion of the topic arose soon after the [[French colonization]] of [[West Africa]], when the Comité d'Etudes commissioned a study on ''desséchement progressif'' to explore the prehistoric expansion of the Sahara Desert.<ref>{{Cite book |author=Mortimore, Michael |url=https://books.google.com/books?id=Dx89AAAAIAAJ&pg=PA12 |title=Adapting to drought: farmers, famines, and desertification in West Africa |publisher=Cambridge University Press |year=1989 |isbn=978-0-521-32312-3 |page=12 |access-date=2016-05-16 |archive-url=https://web.archive.org/web/20230730160046/https://books.google.com/books?id=Dx89AAAAIAAJ&pg=PA12 |archive-date=2023-07-30 |url-status=live}}</ref> The modern study of desertification emerged from the study of the [[Sahel drought|1980s drought]] in the [[Sahel]].<ref name=":6" />
Line 165 ⟶ 176:
== See also ==
* [[Aridification]]
▲* [[Desert greening]]
* [[Detention basin]]
* [[Ecological engineering]]
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* [[Water scarcity]]
* [[World Day to Combat Desertification and Drought]]
* [https://thengr21.com/%e0%a4%ae%e0%a4%b0%e0%a5%81%e0%a4%b8%e0%a5%8d%e0%a4%a5%e0%a4%b2%e0%a5%80%e0%a4%95%e0%a4%b0%e0%a4%a3-2/ There are about 14 deserts located in India.]
 
 
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