Editing Cold seep (section)

=== The Benthic Filter ===
The organisms living at cold seeps have a large impact on the carbon cycle and on climate. Chemosynthetic organisms, specifically methanogenic (methane-consuming) organisms, prohibit the methane seeping up from beneath the seafloor from being released into the water above. Since methane is such a potent greenhouse gas, methane release could cause global warming when gas hydrate reservoirs destabilized.<ref name=":1">{{Cite journal|last1=Sommer|first1=S.|last2=Pfannkuche|first2=O.|last3=Linke|first3=P.|last4=Luff|first4=R.|last5=Greinert|first5=J.|last6=Drews|first6=M.|last7=Gubsch|first7=S.|last8=Pieper|first8=M.|last9=Poser|first9=M.|last10=Viergutz|first10=T.|date=June 2006|title=Efficiency of the benthic filter: Biological control of the emission of dissolved methane from sediments containing shallow gas hydrates at Hydrate Ridge: BIOLOGICAL CONTROL OF EMISSION OF DISSOLVED METHANE|journal=Global Biogeochemical Cycles|language=en|volume=20|issue=2|pages=n/a|doi=10.1029/2004GB002389|s2cid=54695808 |doi-access=free|hdl=1956/1315|hdl-access=free}}</ref> The consumption of methane by aerobic and anaerobic seafloor life is called "the benthic filter".<ref name=":2">{{Cite journal|last1=Boetius|first1=Antje|last2=Wenzhöfer|first2=Frank|date=September 2013|title=Seafloor oxygen consumption fuelled by methane from cold seeps|url=http://www.nature.com/articles/ngeo1926|journal=Nature Geoscience|language=en|volume=6|issue=9|pages=725–734|doi=10.1038/ngeo1926|bibcode=2013NatGe...6..725B|issn=1752-0894|url-access=subscription}}</ref> The first part of this filter is the anaerobic bacteria and archaea underneath the seafloor that consume methane through the [[anaerobic oxidation of methane]] (AOM).<ref name=":2" /> If the flux of methane flowing through the sediment is too large, and the anaerobic bacteria and archaea are consuming the maximum amount of methane, then the excess methane is consumed by free-floating or symbiotic aerobic bacteria above the sediment at the seafloor. The symbiotic bacteria have been found in organisms such as tube worms and clams living at cold seeps; these organisms provide oxygen to the aerobic bacteria as the bacteria provide energy they obtain from the consumption of methane. Understanding how efficient the benthic filter is can help predict how much methane escapes the seafloor at cold seeps and enters the water column and eventually the atmosphere. Studies have shown that 50–90% of methane is consumed at cold seeps with bacterial mats. Areas with clam beds have less than 15% of methane escaping.<ref name=":1" /> Efficiency is determined by a number of factors. The benthic layer is more efficient with low flow of methane, and efficiency decreases as methane flow or the speed of flow increases.<ref name=":2" /> Oxygen demand for cold seep ecosystems is much higher than other benthic ecosystems, so if the bottom water does not have enough oxygen, then the efficiency of aerobic microbes in removing methane is reduced.<ref name=":1" /> The benthic filter cannot affect methane that is not traveling through the sediment. Methane can bypass the benthic filter if it bubbles to the surface or travels through cracks and fissures in the sediment.<ref name=":1" /> These organisms are the only biological sink of methane in the ocean.<ref name=":2" />