Editing Soil (section)

== Processes ==
Soil is a major component of the [[Earth]]'s [[ecosystem]]. The world's ecosystems are impacted in far-reaching ways by the processes carried out in the soil, with effects ranging from [[ozone depletion]] and [[global warming]] to [[rainforest destruction]] and [[water pollution]]. With respect to Earth's [[carbon cycle]], soil acts as an important [[carbon sink|carbon reservoir]],<ref>{{cite journal |last1=Amelung |first1=Wulf |last2=Bossio |first2=Deborah |last3=De Vries |first3=Wim |last4=Kögel-Knabner |first4=Ingrid|author4-link=Ingrid Kögel-Knabner |last5=Lehmann |first5=Johannes |last6=Amundson |first6=Ronald |last7=Bol |first7=Roland |last8=Collins |first8=Chris |last9=Lal |first9=Rattan |last10=Leifeld |first10=Jens |last11=Minasny |first11=Buniman |last12=Pan |first12=Gen-Xing |last13=Paustian |first13=Keith |last14=Rumpel |first14=Cornelia |last15=Sanderman |first15=Jonathan |last16=Van Groeningen |first16=Jan Willem |last17=Mooney |first17=Siân |last18=Van Wesemael |first18=Bas |last19=Wander |first19=Michelle |last20=Chabbi |first20=Abad |date=27 October 2020 |title=Towards a global-scale soil climate mitigation strategy |journal=[[Nature Communications]] |language=en |volume=11 |issue=1 |pages=5427 |doi=10.1038/s41467-020-18887-7 |pmid=33110065 |pmc=7591914 |bibcode=2020NatCo..11.5427A |issn=2041-1723 |url=https://www.nature.com/articles/s41467-020-18887-7.pdf |access-date=29 December 2024 |doi-access=free }}</ref> and it is potentially one of the most reactive to human disturbance<ref>{{cite journal |last1=Pouyat |first1=Richard |last2=Groffman |first2=Peter |last3=Yesilonis |first3=Ian |last4= Hernandez |first4=Luis |journal=[[Environmental Pollution (journal)|Environmental Pollution]] |volume=116 |issue=Supplement 1 |title=Soil carbon pools and fluxes in urban ecosystems |url=https://www.researchgate.net/publication/11526697 |date=February 2002 |pages=S107–S118 |doi=10.1016/S0269-7491(01)00263-9 |pmid=11833898 |access-date=29 December 2024 |quote=Our analysis of pedon data from several disturbed soil profiles suggests that physical disturbances and anthropogenic inputs of various materials (direct effects) can greatly alter the amount of C stored in these human "made" soils. }}</ref> and [[climate change]].<ref name="Davidson">{{cite journal |last1=Davidson |first1=Eric A. |last2=Janssens |first2=Ivan A. |journal=[[Nature (journal)|Nature]] |volume=440 |title=Temperature sensitivity of soil carbon decomposition and feedbacks to climate change |year=2006 |issue=9 March 2006 |pages=165‒73 |url=https://www.nature.com/articles/nature04514.pdf |doi=10.1038/nature04514 |pmid=16525463 |bibcode=2006Natur.440..165D |s2cid=4404915 |access-date=29 December 2024 |doi-access=free }}</ref> As the planet warms, it has been predicted that soils will add carbon dioxide to the atmosphere due to increased [[Soil biology|biological]] activity at higher temperatures, a [[positive feedback]] (amplification).<ref>{{cite journal |last=Powlson |first=David |journal=[[Nature (journal)|Nature]] |volume=433 |title=Will soil amplify climate change? |year=2005 |issue=20 January 2005 |pages=204‒05 |url=https://climatescience.ru/uploads/pubs/0/0f/0fa/0fa597c6991df9576bcad69f4f3113f8.pdf |doi=10.1038/433204a |pmid=15662396 |bibcode=2005Natur.433..204P |s2cid=35007042 |access-date=29 December 2024 |archive-date=22 September 2022 |archive-url=https://web.archive.org/web/20220922110017/https://fr.art1lib.org/book/10543301/528a68 |url-status=live }}</ref> This prediction has, however, been questioned on consideration of more recent knowledge on [[soil carbon]] turnover.<ref>{{cite journal |last1=Bradford |first1=Mark A. |last2=Wieder |first2=William R. |last3=Bonan |first3=Gordon B. |last4=Fierer |first4=Noah |last5=Raymond |first5=Peter A. |last6=Crowther |first6=Thomas W. |journal=[[Nature Climate Change]] |volume=6 |title=Managing uncertainty in soil carbon feedbacks to climate change |url=https://www.crowtherlab.com/wp-content/uploads/2019/07/bradford2016NCC.pdf |year=2016 |issue=27 July 2016 |pages=751–758 |doi=10.1038/nclimate3071 |access-date=29 December 2024 |bibcode=2016NatCC...6..751B |s2cid=43955196 |archive-date=10 April 2017 |archive-url=https://web.archive.org/web/20170410025316/http://fiererlab.org/wp-content/uploads/2014/09/Bradford_etal_2016_NCC.pdf |url-status=live }}</ref>

Soil acts as an engineering medium, a habitat for [[soil organisms]], a recycling system for [[nutrients]] and [[organic waste]]s, a regulator of [[water quality]], a modifier of [[Atmospheric chemistry|atmospheric composition]], and a medium for [[plant growth]], making it a critically important provider of [[ecosystem services]].<ref>{{cite journal |last1=Dominati |first1=Estelle |last2=Patterson |first2=Murray |last3=Mackay |first3=Alec |journal=[[Ecological Economics (journal)|Ecological Economics]] |volume=69 |issue=9 |title=A framework for classifying and quantifying the natural capital and ecosystem services of soils |year=2010 |url=https://www.researchgate.net/publication/223852147 |pages=1858‒68 |doi=10.1016/j.ecolecon.2010.05.002 |bibcode=2010EcoEc..69.1858D |access-date=29 December 2024 |archive-url=https://web.archive.org/web/20170808082847/http://esanalysis.colmex.mx/Sorted%20Papers/2010/2010%20NZL%20-3F%20Phys.pdf |archive-date=8 August 2017 |url-status=live }}</ref> Since soil has a tremendous range of available [[Ecological niche|niches]] and [[habitat]]s, it contains a prominent part of the Earth's [[genetic diversity]]. A gram of soil can contain billions of organisms, belonging to thousands of species, mostly microbial and largely still unexplored.<ref>{{cite journal |last=Dykhuizen |first=Daniel E. |journal=[[Antonie van Leeuwenhoek (journal)|Antonie van Leeuwenhoek]] |volume=73 |issue=1 |title=Santa Rosalia revisited: why are there so many species of bacteria? |year=1998 |url=https://www.researchgate.net/publication/13682480 |pages=25‒33 |doi=10.1023/A:1000665216662 |pmid=9602276 |s2cid=17779069 |access-date=29 December 2024 }}</ref><ref>{{cite journal |last1=Torsvik |first1=Vigdis |last2=Øvreås |first2=Lise |journal=[[Current Opinion in Microbiology]] |volume=5 |issue=3 |title=Microbial diversity and function in soil: from genes to ecosystems |year=2002 |pages=240‒45 |url=https://www.academia.edu/13038690 |doi=10.1016/S1369-5274(02)00324-7 |pmid=12057676 |access-date=29 December 2024 }}</ref> Soil has a [[mean]] [[Prokaryote|prokaryotic]] density of roughly 10<sup>8</sup> organisms per gram,<ref>{{cite journal |last1=Raynaud |first1=Xavier |last2=Nunan |first2=Naoise |journal=[[PLOS ONE]] |volume=9 |issue=1 |title=Spatial ecology of bacteria at the microscale in soil |year=2014 |page=e87217 |doi=10.1371/journal.pone.0087217 |pmid=24489873 |pmc=3905020 |bibcode=2014PLoSO...987217R |doi-access=free }}</ref> whereas the ocean has no more than 10<sup>7</sup> prokaryotic organisms per milliliter (gram) of seawater.<ref>{{cite journal |last1=Whitman |first1=William B. |last2=Coleman |first2=David C. |last3=Wiebe |first3=William J. |journal=[[Proceedings of the National Academy of Sciences of the USA]] |volume=95 |issue=12 |title=Prokaryotes: the unseen majority |year=1998 |pages=6578‒83 |doi=10.1073/pnas.95.12.6578 |pmid=9618454 |pmc=33863 |bibcode=1998PNAS...95.6578W |doi-access=free }}</ref> [[Soil organic matter|Organic carbon]] held in soil is eventually returned to the atmosphere through the process of [[cellular respiration|respiration]] carried out by [[heterotrophic]] organisms, but a substantial part is retained in the soil in the form of soil organic matter; [[tillage]] usually increases the rate of [[soil respiration]], leading to the depletion of soil organic matter.<ref>{{cite journal |last1=Schlesinger |first1=William H. |last2=Andrews |first2=Jeffrey A. |journal=Biogeochemistry |volume=48 |issue=1 |title=Soil respiration and the global carbon cycle |year=2000 |url=https://www.researchgate.net/publication/51997678 |pages=7‒20 |doi=10.1023/A:1006247623877 |bibcode=2000Biogc..48....7S |s2cid=94252768 |access-date=29 December 2024 }}</ref> Since plant roots need oxygen, [[aeration]] is an important characteristic of soil. This ventilation can be accomplished via networks of interconnected [[Pore space in soil|soil pores]], which also absorb and hold rainwater making it readily available for uptake by plants. Since plants require a nearly continuous supply of water, but most regions receive sporadic rainfall, the [[Soil water (retention)|water-holding capacity]] of soils is vital for plant survival.<ref>{{cite journal |last1=Denmead |first1=Owen Thomas |last2=Shaw |first2=Robert Harold |journal=[[Agronomy Journal]] |volume=54 |issue=5 |title=Availability of soil water to plants as affected by soil moisture content and meteorological conditions |year=1962 |url=https://www.researchgate.net/publication/250098028 |pages=385‒90 |doi=10.2134/agronj1962.00021962005400050005x |bibcode=1962AgrJ...54..385D |access-date=29 December 2024 }}</ref>

Soils can effectively remove impurities,<ref>{{cite journal |last1=House |first1=Christopher H. |last2=Bergmann |first2=Ben A. |last3=Stomp |first3=Anne-Marie |last4=Frederick |first4=Douglas J. |journal=Ecological Engineering |volume=12 |issue=1–2 |title=Combining constructed wetlands and aquatic and soil filters for reclamation and reuse of water |year=1999 |url=https://www.researchgate.net/publication/222464331 |pages=27–38 |doi=10.1016/S0925-8574(98)00052-4 |bibcode=1999EcEng..12...27H |access-date=29 December 2024 }}</ref> kill disease agents,<ref>{{cite journal |last1=Van Bruggen |first1=Ariena H.C. |last2=Semenov |first2=Alexander M. |journal=Applied Soil Ecology |volume=15 |issue=1 |title=In search of biological indicators for soil health and disease suppression |year=2000 |url=https://www.researchgate.net/publication/222520930 |pages=13–24 |doi=10.1016/S0929-1393(00)00068-8 |bibcode=2000AppSE..15...13V |access-date=29 December 2024 }}</ref> and degrade [[contaminants]], this latter property being called [[natural attenuation]].<ref>{{cite web |url=https://semspub.epa.gov/work/HQ/401611.pdf |title=Community guide to monitored natural attenuation |access-date=29 December 2024 }}</ref> Typically, soils maintain a net absorption of [[oxygen]] and [[methane]] and undergo a net release of [[carbon dioxide]] and [[nitrous oxide]].<ref>{{cite journal |last1=Linn |first1=Daniel Myron |last2=Doran |first2=John W. |journal=[[Soil Science Society of America Journal]] |volume=48 |issue=6 |title=Effect of water-filled pore space on carbon dioxide and nitrous oxide production in tilled and nontilled soils |year=1984 |url=https://fr.1lib.sk/book/55339558/7bc22a |pages=1267–72 |doi=10.2136/sssaj1984.03615995004800060013x |access-date=29 December 2024 |bibcode=1984SSASJ..48.1267L |archive-date=18 March 2023 |archive-url=https://web.archive.org/web/20230318043457/https://fr.art1lib.org/book/23108771/821c3f |url-status=live }}</ref> Soils offer plants physical support, air, water, temperature moderation, nutrients, and protection from toxins.<ref>{{cite book |last1=Gregory |first1=Peter J. |last2=Nortcliff |first2=Stephen |date=2013 |title=Soil conditions and plant growth |isbn=9781405197700 |publisher=[[Wiley-Blackwell]] |location=Hoboken, New Jersey |url=https://fr.1lib.sk/book/2156095/a3577f |access-date=29 December 2024 |archive-date=22 April 2023 |archive-url=https://web.archive.org/web/20230422182643/https://fr.book4you.org/book/2156095/fd863f |url-status=live }}</ref> Soils provide readily available nutrients to plants and animals by converting dead organic matter into various nutrient forms.<ref>{{cite book |last1=Bot |first1=Alexandra |last2=Benites |first2=José |date=2005 |title=The importance of soil organic matter: key to drought-resistant soil and sustained food and production |isbn=978-92-5-105366-9 |publisher=[[Food and Agriculture Organization of the United Nations]] |location=Rome |url=http://www.fao.org/3/a-a0100e.pdf |access-date=29 December 2024 }}</ref>