Editing Carbon cycle (section)

=== Terrestrial carbon in the water cycle ===
[[File:Where carbon goes when water flows.jpg|thumb|upright=2| {{center|Where terrestrial carbon goes when water flows{{hsp}}<ref name=Ward2017>{{cite journal |last1=Ward |first1=Nicholas D. |last2=Bianchi |first2=Thomas S. |last3=Medeiros |first3=Patricia M. |last4=Seidel |first4=Michael |last5=Richey |first5=Jeffrey E. |last6=Keil |first6=Richard G. |last7=Sawakuchi |first7=Henrique O. |title=Where Carbon Goes When Water Flows: Carbon Cycling across the Aquatic Continuum |journal=Frontiers in Marine Science |date=31 January 2017 |volume=4 |doi=10.3389/fmars.2017.00007 |doi-access=free }}{{Creative Commons text attribution notice|cc=by4|url=|author(s)=|vrt=|from this source=yes}}</ref>}}]]

The movement of terrestrial carbon in the water cycle is shown in the diagram on the right and explained below:{{hsp}}<ref name=Ward2017 />

# Atmospheric particles act as [[cloud condensation nuclei]], promoting cloud formation.<ref name=Kerminen2000>{{cite journal |last1=Kerminen |first1=Veli-Matti |last2=Virkkula |first2=Aki |last3=Hillamo |first3=Risto |last4=Wexler |first4=Anthony S. |last5=Kulmala |first5=Markku |title=Secondary organics and atmospheric cloud condensation nuclei production |journal=Journal of Geophysical Research: Atmospheres |date=16 April 2000 |volume=105 |issue=D7 |pages=9255–9264 |doi=10.1029/1999JD901203 |bibcode=2000JGR...105.9255K }}</ref><ref name=Riipinen2011>{{cite journal |last1=Riipinen |first1=I. |last2=Pierce |first2=J. R. |last3=Yli-Juuti |first3=T. |last4=Nieminen |first4=T. |last5=Häkkinen |first5=S. |last6=Ehn |first6=M. |last7=Junninen |first7=H. |last8=Lehtipalo |first8=K. |last9=Petäjä |first9=T. |last10=Slowik |first10=J. |last11=Chang |first11=R. |last12=Shantz |first12=N. C. |last13=Abbatt |first13=J. |last14=Leaitch |first14=W. R. |last15=Kerminen |first15=V.-M. |last16=Worsnop |first16=D. R. |last17=Pandis |first17=S. N. |last18=Donahue |first18=N. M. |last19=Kulmala |first19=M. |title=Organic condensation: a vital link connecting aerosol formation to cloud condensation nuclei (CCN) concentrations |journal=Atmospheric Chemistry and Physics |date=27 April 2011 |volume=11 |issue=8 |pages=3865–3878 |doi=10.5194/acp-11-3865-2011 |doi-access=free |bibcode=2011ACP....11.3865R }}</ref>
#Raindrops absorb [[organic carbon|organic]] and [[inorganic carbon]] through particle scavenging and adsorption of organic vapors while falling toward Earth.<ref name=Waterloo2006>{{cite journal |last1=Waterloo |first1=Maarten J. |last2=Oliveira |first2=Sylvia M. |last3=Drucker |first3=Debora P. |last4=Nobre |first4=Antonio D. |last5=Cuartas |first5=Luz A. |last6=Hodnett |first6=Martin G. |last7=Langedijk |first7=Ivar |last8=Jans |first8=Wilma W. P. |last9=Tomasella |first9=Javier |last10=de Araújo |first10=Alessandro C. |last11=Pimentel |first11=Tania P. |last12=Múnera Estrada |first12=Juan C. |title=Export of organic carbon in run-off from an Amazonian rainforest blackwater catchment |journal=Hydrological Processes |date=15 August 2006 |volume=20 |issue=12 |pages=2581–2597 |doi=10.1002/hyp.6217 |bibcode=2006HyPr...20.2581W }}</ref><ref name=Neu2016>{{cite journal |last1=Neu |first1=Vania |last2=Ward |first2=Nicholas D. |last3=Krusche |first3=Alex V. |last4=Neill |first4=Christopher |title=Dissolved Organic and Inorganic Carbon Flow Paths in an Amazonian Transitional Forest |journal=Frontiers in Marine Science |date=28 June 2016 |volume=3 |doi=10.3389/fmars.2016.00114 |doi-access=free }}</ref>
#Burning and volcanic eruptions produce highly condensed [[Polycyclic aromatic hydrocarbon|polycyclic aromatic molecules]] (i.e. [[black carbon]]) that is returned to the atmosphere along with greenhouse gases such as CO<sub>2</sub>.<ref name=Baldock2004>{{cite journal |last1=Baldock |first1=J.A. |last2=Masiello |first2=C.A. |last3=Gélinas |first3=Y. |last4=Hedges |first4=J.I. |title=Cycling and composition of organic matter in terrestrial and marine ecosystems |journal=Marine Chemistry |date=December 2004 |volume=92 |issue=1–4 |pages=39–64 |doi=10.1016/j.marchem.2004.06.016 |bibcode=2004MarCh..92...39B }}</ref><ref name=Myers-Pigg2016>{{cite journal |last1=Myers-Pigg |first1=Allison N. |last2=Griffin |first2=Robert J. |last3=Louchouarn |first3=Patrick |last4=Norwood |first4=Matthew J. |last5=Sterne |first5=Amanda |last6=Cevik |first6=Basak Karakurt |title=Signatures of Biomass Burning Aerosols in the Plume of a Saltmarsh Wildfire in South Texas |journal=Environmental Science & Technology |date=6 September 2016 |volume=50 |issue=17 |pages=9308–9314 |doi=10.1021/acs.est.6b02132 |pmid=27462728 |bibcode=2016EnST...50.9308M }}</ref> 
#Terrestrial plants fix atmospheric CO<sub>2</sub> through [[photosynthesis]], returning a fraction back to the atmosphere through [[respiration (physiology)|respiration]].<ref name=Field1998>{{cite journal |last1=Field |first1=Christopher B. |last2=Behrenfeld |first2=Michael J. |last3=Randerson |first3=James T. |last4=Falkowski |first4=Paul |title=Primary Production of the Biosphere: Integrating Terrestrial and Oceanic Components |journal=Science |date=10 July 1998 |volume=281 |issue=5374 |pages=237–240 |doi=10.1126/science.281.5374.237 |pmid=9657713 |bibcode=1998Sci...281..237F |url=https://escholarship.org/uc/item/9gm7074q }}</ref> [[Lignin]] and [[cellulose]]s represent as much as 80% of the organic carbon in forests and 60% in pastures.<ref name=Martens2004>{{cite journal |last1=Martens |first1=Dean A. |last2=Reedy |first2=Thomas E. |last3=Lewis |first3=David T. |title=Soil organic carbon content and composition of 130-year crop, pasture and forest land-use managements |journal=Global Change Biology |date=January 2004 |volume=10 |issue=1 |pages=65–78 |doi=10.1046/j.1529-8817.2003.00722.x |bibcode=2004GCBio..10...65M |url=https://digitalcommons.unl.edu/agronomyfacpub/124 }}</ref><ref name=Bose2009>{{cite journal |last1=Bose |first1=Samar K. |last2=Francis |first2=Raymond C. |last3=Govender |first3=Mark |last4=Bush |first4=Tamara |last5=Spark |first5=Andrew |title=Lignin content versus syringyl to guaiacyl ratio amongst poplars |journal=Bioresource Technology |date=February 2009 |volume=100 |issue=4 |pages=1628–1633 |doi=10.1016/j.biortech.2008.08.046 |pmid=18954979 |bibcode=2009BiTec.100.1628B }}</ref> 
#[[Litterfall]] and root organic carbon mix with sedimentary material to form organic soils where plant-derived and petrogenic organic carbon is both stored and transformed by microbial and fungal activity.<ref name=Schlesinger2000>{{cite journal |last1=Schlesinger |first1=William H. |last2=Andrews |first2=Jeffrey A. |title=Soil respiration and the global carbon cycle |journal=Biogeochemistry |date=2000 |volume=48 |issue=1 |pages=7–20 |doi=10.1023/A:1006247623877 |bibcode=2000Biogc..48....7S }}</ref><ref name=Schmidt2011>{{cite journal |last1=Schmidt |first1=Michael W. I. |last2=Torn |first2=Margaret S. |last3=Abiven |first3=Samuel |last4=Dittmar |first4=Thorsten |last5=Guggenberger |first5=Georg |last6=Janssens |first6=Ivan A. |last7=Kleber |first7=Markus |last8=Kögel-Knabner |first8=Ingrid |author8-link=Ingrid Kögel-Knabner|last9=Lehmann |first9=Johannes |last10=Manning |first10=David A. C. |last11=Nannipieri |first11=Paolo |last12=Rasse |first12=Daniel P. |last13=Weiner |first13=Steve |last14=Trumbore |first14=Susan E. |title=Persistence of soil organic matter as an ecosystem property |journal=Nature |date=October 2011 |volume=478 |issue=7367 |pages=49–56 |doi=10.1038/nature10386 |pmid=21979045 |bibcode=2011Natur.478...49S |url=https://digital.library.unt.edu/ark:/67531/metadc844476/ }}</ref><ref name=Lehmann2015>{{cite journal |last1=Lehmann |first1=Johannes |last2=Kleber |first2=Markus |title=The contentious nature of soil organic matter |journal=Nature |date=December 2015 |volume=528 |issue=7580 |pages=60–68 |doi=10.1038/nature16069 |pmid=26595271 |bibcode=2015Natur.528...60L }}</ref>
#Water absorbs plant and settled aerosol-derived [[dissolved organic carbon]] (DOC) and [[dissolved inorganic carbon]] (DIC) as it passes over forest canopies (i.e. [[throughfall]]) and along plant trunks/stems (i.e. [[stemflow]]).<ref>{{cite journal |last1=Qualls |first1=Robert G. |last2=Haines |first2=Bruce L. |title=Biodegradability of Dissolved Organic Matter in Forest Throughfall, Soil Solution, and Stream Water |journal=Soil Science Society of America Journal |date=March 1992 |volume=56 |issue=2 |pages=578–586 |doi=10.2136/sssaj1992.03615995005600020038x |bibcode=1992SSASJ..56..578Q }}</ref> Biogeochemical transformations take place as water soaks into soil solution and groundwater reservoirs<ref name=Grøn1992>{{cite journal |last1=Grøn |first1=Christian |last2=Tørsløv |first2=Jens |last3=Albrechtsen |first3=Hans-Jørgen |last4=Jensen |first4=Hanne Møller |title=Biodegradability of dissolved organic carbon in groundwater from an unconfined aquifer |journal=Science of the Total Environment |date=May 1992 |volume=117-118 |pages=241–251 |doi=10.1016/0048-9697(92)90091-6 |bibcode=1992ScTEn.117..241G }}</ref><ref name=Pabich2001>{{cite journal |last1=Pabich |first1=Wendy J. |last2=Valiela |first2=Ivan |last3=Hemond |first3=Harold F. |title=Relationship between DOC concentration and vadose zone thickness and depth below water table in groundwater of Cape Cod, U.S.A. |journal=Biogeochemistry |date=2001 |volume=55 |issue=3 |pages=247–268 |doi=10.1023/A:1011842918260 |bibcode=2001Biogc..55..247P }}</ref> and [[overland flow]] occurs when soils are completely saturated,<ref name=Linsley1975>{{cite book |last1=Linsley |first1=Ray K. |title=Solutions Manual to Accompany Hydrology for Engineers |date=1975 |publisher=McGraw-Hill |oclc=24765393 }}{{pn|date=July 2024}}</ref> or rainfall occurs more rapidly than saturation into soils.<ref name=Horton1933>{{cite journal |title=The Rôle of infiltration in the hydrologic cycle |journal=Eos, Transactions American Geophysical Union |date=June 1933 |volume=14 |issue=1 |pages=446–460 |doi=10.1029/TR014i001p00446 |bibcode=1933TrAGU..14..446H |last1=Horton |first1=Robert E. }}</ref>
#Organic carbon derived from the terrestrial biosphere and ''in situ'' [[primary production]] is decomposed by microbial communities in rivers and streams along with physical decomposition (i.e. [[photo-oxidation]]), resulting in a flux of CO<sub>2</sub> from rivers to the atmosphere that are the same order of magnitude as the amount of carbon sequestered annually by the terrestrial biosphere.<ref name=Richey2002>{{cite journal |last1=Richey |first1=Jeffrey E. |last2=Melack |first2=John M. |last3=Aufdenkampe |first3=Anthony K. |last4=Ballester |first4=Victoria M. |last5=Hess |first5=Laura L. |title=Outgassing from Amazonian rivers and wetlands as a large tropical source of atmospheric CO2 |journal=Nature |date=April 2002 |volume=416 |issue=6881 |pages=617–620 |doi=10.1038/416617a |pmid=11948346 }}</ref><ref name=Cole2007>{{cite journal |last1=Cole |first1=J. J. |last2=Prairie |first2=Y. T. |last3=Caraco |first3=N. F. |last4=McDowell |first4=W. H. |last5=Tranvik |first5=L. J. |last6=Striegl |first6=R. G. |last7=Duarte |first7=C. M. |last8=Kortelainen |first8=P. |last9=Downing |first9=J. A. |last10=Middelburg |first10=J. J. |last11=Melack |first11=J. |title=Plumbing the Global Carbon Cycle: Integrating Inland Waters into the Terrestrial Carbon Budget |journal=Ecosystems |date=February 2007 |volume=10 |issue=1 |pages=172–185 |doi=10.1007/s10021-006-9013-8 |bibcode=2007Ecosy..10..172C }}</ref><ref name=Raymond2013>{{cite journal |last1=Raymond |first1=Peter A. |last2=Hartmann |first2=Jens |last3=Lauerwald |first3=Ronny |last4=Sobek |first4=Sebastian |last5=McDonald |first5=Cory |last6=Hoover |first6=Mark |last7=Butman |first7=David |last8=Striegl |first8=Robert |last9=Mayorga |first9=Emilio |last10=Humborg |first10=Christoph |last11=Kortelainen |first11=Pirkko |last12=Dürr |first12=Hans |last13=Meybeck |first13=Michel |last14=Ciais |first14=Philippe |last15=Guth |first15=Peter |title=Global carbon dioxide emissions from inland waters |journal=Nature |date=21 November 2013 |volume=503 |issue=7476 |pages=355–359 |doi=10.1038/nature12760 |pmid=24256802 |bibcode=2013Natur.503..355R |url=http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-213816 }}</ref> Terrestrially-derived macromolecules such as lignin{{hsp}}<ref name=Ward2013>{{cite journal |last1=Ward |first1=Nicholas D. |last2=Keil |first2=Richard G. |last3=Medeiros |first3=Patricia M. |last4=Brito |first4=Daimio C. |last5=Cunha |first5=Alan C. |last6=Dittmar |first6=Thorsten |last7=Yager |first7=Patricia L. |last8=Krusche |first8=Alex V. |last9=Richey |first9=Jeffrey E. |title=Degradation of terrestrially derived macromolecules in the Amazon River |journal=Nature Geoscience |date=July 2013 |volume=6 |issue=7 |pages=530–533 |doi=10.1038/ngeo1817 |bibcode=2013NatGe...6..530W }}</ref> and [[black carbon]]{{hsp}}<ref name=Myers-Pigg2015>{{cite journal |last1=Myers-Pigg |first1=Allison N. |last2=Louchouarn |first2=Patrick |last3=Amon |first3=Rainer M. W. |last4=Prokushkin |first4=Anatoly |last5=Pierce |first5=Kayce |last6=Rubtsov |first6=Alexey |title=Labile pyrogenic dissolved organic carbon in major Siberian Arctic rivers: Implications for wildfire-stream metabolic linkages |journal=Geophysical Research Letters |date=28 January 2015 |volume=42 |issue=2 |pages=377–385 |doi=10.1002/2014GL062762 |bibcode=2015GeoRL..42..377M |doi-access=free }}</ref> are decomposed into smaller components and [[monomer]]s, ultimately being converted to CO<sub>2</sub>, metabolic intermediates, or [[Biomass (ecology)|biomass]].
#Lakes, reservoirs, and [[floodplain]]s typically store large amounts of organic carbon and sediments, but also experience net [[heterotrophy]] in the water column, resulting in a net flux of CO<sub>2</sub> to the atmosphere that is roughly one order of magnitude less than rivers.<ref name=Tranvik2009>{{cite journal |last1=Tranvik |first1=Lars J. |last2=Downing |first2=John A. |last3=Cotner |first3=James B. |last4=Loiselle |first4=Steven A. |last5=Striegl |first5=Robert G. |last6=Ballatore |first6=Thomas J. |last7=Dillon |first7=Peter |last8=Finlay |first8=Kerri |last9=Fortino |first9=Kenneth |last10=Knoll |first10=Lesley B. |last11=Kortelainen |first11=Pirkko L. |last12=Kutser |first12=Tiit |last13=Larsen |first13=Soren. |last14=Laurion |first14=Isabelle |last15=Leech |first15=Dina M. |last16=McCallister |first16=S. Leigh |last17=McKnight |first17=Diane M. |last18=Melack |first18=John M. |last19=Overholt |first19=Erin |last20=Porter |first20=Jason A. |last21=Prairie |first21=Yves |last22=Renwick |first22=William H. |last23=Roland |first23=Fabio |last24=Sherman |first24=Bradford S. |last25=Schindler |first25=David W. |last26=Sobek |first26=Sebastian |last27=Tremblay |first27=Alain |last28=Vanni |first28=Michael J. |last29=Verschoor |first29=Antonie M. |last30=von Wachenfeldt |first30=Eddie |last31=Weyhenmeyer |first31=Gesa A. |title=Lakes and reservoirs as regulators of carbon cycling and climate |journal=Limnology and Oceanography |date=November 2009 |volume=54 |issue=6part2 |pages=2298–2314 |doi=10.4319/lo.2009.54.6_part_2.2298 |bibcode=2009LimOc..54.2298T }}</ref><ref name=Raymond2013 /> Methane production is also typically high in the [[anoxic waters|anoxic]] sediments of floodplains, lakes, and reservoirs.<ref name=Bastviken2004>{{cite journal |last1=Bastviken |first1=David |last2=Cole |first2=Jonathan |last3=Pace |first3=Michael |last4=Tranvik |first4=Lars |title=Methane emissions from lakes: Dependence of lake characteristics, two regional assessments, and a global estimate |journal=Global Biogeochemical Cycles |date=December 2004 |volume=18 |issue=4 |doi=10.1029/2004GB002238 |bibcode=2004GBioC..18.4009B }}</ref>
#Primary production is typically enhanced in [[river plume]]s due to the export of [[fluvial]] nutrients.<ref name=Cooley2007>{{cite journal |last1=Cooley |first1=S. R. |last2=Coles |first2=V. J. |last3=Subramaniam |first3=A. |last4=Yager |first4=P. L. |title=Seasonal variations in the Amazon plume-related atmospheric carbon sink |journal=Global Biogeochemical Cycles |date=September 2007 |volume=21 |issue=3 |doi=10.1029/2006GB002831 |bibcode=2007GBioC..21.3014C }}</ref><ref name=Subramaniam2008>{{cite journal |last1=Subramaniam |first1=A. |last2=Yager |first2=P. L. |last3=Carpenter |first3=E. J. |last4=Mahaffey |first4=C. |last5=Björkman |first5=K. |last6=Cooley |first6=S. |last7=Kustka |first7=A. B. |last8=Montoya |first8=J. P. |last9=Sañudo-Wilhelmy |first9=S. A. |last10=Shipe |first10=R. |last11=Capone |first11=D. G. |title=Amazon River enhances diazotrophy and carbon sequestration in the tropical North Atlantic Ocean |journal=Proceedings of the National Academy of Sciences |date=29 July 2008 |volume=105 |issue=30 |pages=10460–10465 |doi=10.1073/pnas.0710279105 |doi-access=free |pmid=18647838 |pmc=2480616 }}</ref> Nevertheless, [[estuarine]] waters are a source of CO<sub>2</sub> to the atmosphere, globally.<ref name=Cai2011>{{cite journal |last1=Cai |first1=Wei-Jun |title=Estuarine and Coastal Ocean Carbon Paradox: CO 2 Sinks or Sites of Terrestrial Carbon Incineration? |journal=Annual Review of Marine Science |date=15 January 2011 |volume=3 |issue=1 |pages=123–145 |doi=10.1146/annurev-marine-120709-142723 |pmid=21329201 |bibcode=2011ARMS....3..123C }}</ref>
#[[Coastal marsh]]es both store and export [[blue carbon]].<ref name=Odum1979>{{cite book |doi=10.1007/978-1-4615-9146-7 |title=Ecological Processes in Coastal and Marine Systems |date=1979 |isbn=978-1-4615-9148-1 |editor-last1=Livingston |editor-first1=Robert J. }}{{pn|date=July 2024}}</ref><ref name=Dittmar2001>{{cite journal |last1=Dittmar |first1=Thorsten |last2=Lara |first2=Rubén José |last3=Kattner |first3=Gerhard |title=River or mangrove? Tracing major organic matter sources in tropical Brazilian coastal waters |journal=Marine Chemistry |date=March 2001 |volume=73 |issue=3–4 |pages=253–271 |doi=10.1016/s0304-4203(00)00110-9 |bibcode=2001MarCh..73..253D }}</ref><ref name=Moore2011>{{cite journal |last1=Moore |first1=W.S. |last2=Beck |first2=M. |last3=Riedel |first3=T. |last4=Rutgers van der Loeff |first4=M. |last5=Dellwig |first5=O. |last6=Shaw |first6=T.J. |last7=Schnetger |first7=B. |last8=Brumsack |first8=H.-J. |title=Radium-based pore water fluxes of silica, alkalinity, manganese, DOC, and uranium: A decade of studies in the German Wadden Sea |journal=Geochimica et Cosmochimica Acta |date=November 2011 |volume=75 |issue=21 |pages=6535–6555 |doi=10.1016/j.gca.2011.08.037 |bibcode=2011GeCoA..75.6535M }}</ref> [[Marsh]]es and [[wetland]]s are suggested to have an equivalent flux of CO<sub>2</sub> to the atmosphere as rivers, globally.<ref name=Wehrli2013>{{cite journal |last1=Wehrli |first1=Bernhard |title=Conduits of the carbon cycle |journal=Nature |date=November 2013 |volume=503 |issue=7476 |pages=346–347 |doi=10.1038/503346a |pmid=24256800 }}</ref>
#[[Continental shelves]] and the [[open ocean]] typically absorb CO<sub>2</sub> from the atmosphere.<ref name=Cai2011 /> 
#The marine [[biological pump]] sequesters a small but significant fraction of the absorbed CO<sub>2</sub> as organic carbon in [[marine sediment]]s ([[#The marine biological pump|see below]]).<ref name=Moran2016>{{cite journal |last1=Moran |first1=Mary Ann |last2=Kujawinski |first2=Elizabeth B. |last3=Stubbins |first3=Aron |last4=Fatland |first4=Rob |last5=Aluwihare |first5=Lihini I. |last6=Buchan |first6=Alison |last7=Crump |first7=Byron C. |last8=Dorrestein |first8=Pieter C. |last9=Dyhrman |first9=Sonya T. |last10=Hess |first10=Nancy J. |last11=Howe |first11=Bill |last12=Longnecker |first12=Krista |last13=Medeiros |first13=Patricia M. |last14=Niggemann |first14=Jutta |last15=Obernosterer |first15=Ingrid |last16=Repeta |first16=Daniel J. |last17=Waldbauer |first17=Jacob R. |title=Deciphering ocean carbon in a changing world |journal=Proceedings of the National Academy of Sciences |date=22 March 2016 |volume=113 |issue=12 |pages=3143–3151 |doi=10.1073/pnas.1514645113 |doi-access=free |pmid=26951682 |pmc=4812754 |bibcode=2016PNAS..113.3143M }}</ref><ref name=Ward2017 />

{{clear}}