Editing Mudflat (section)

{{short description|Coastal wetlands where sediments have been deposited by tides or rivers}}
{{Redirect|Sand flat||Sand Flat (disambiguation){{!}}Sand Flat}}
[[Image:Tidal flat general sketch.png|upright=1.45|thumb|General sketch-map of a tidal plain, showing the typical tripartition in [[supratidal zone|supratidal]], [[intertidal]] and [[subtidal]] zones. The most apparent character of the area is the development of tidal channels, affecting mainly the [[intertidal zone]]. In this case, the tidal flat is protected seaward by a [[shoal|beach barrier]], but in many cases (low-energy [[water waves|waves]] and [[longshore currents]]) the tidal flats may directly pass into a shallow marine environment.]]

'''Mudflats''' or '''mud flats''', also known as '''tidal flats''' or, in Ireland, '''slob''' or '''slobs''',<ref>{{Cite web|url=http://www.askaboutireland.ie/enfo/irelands-environment/county-focus/wexford/wexford-sloblands/|title=Sloblands|website=www.askaboutireland.ie}}</ref><ref>{{Cite news|url=https://www.irishtimes.com/news/celebrating-the-slobs-1.48177|title=Celebrating the Slobs|first=Richard|last=Roche|newspaper=The Irish Times}}</ref> are [[coastal wetland]]s that form in intertidal areas where sediments have been deposited by [[tide]]s or [[river]]s. A global analysis published in 2019 suggested that tidal flat ecosystems are as extensive globally as [[mangrove]]s, covering at least {{convert|127,921|km2|mi2|abbr=on}} of the [[Earth]]'s surface.<ref name=Murray>
{{Citation | last1  = Murray | first1 = N.J. | last2 = Phinn | first2 = S.R. | last3 = DeWitt | first3 = M. | last4 = Ferrari | first4 = R. | last5 = Johnston | first5 = R. | last6 = Lyons| first6 = M.B. |last7 = Clinton | first7 = N. |last8 = Thau| first8 = D. | last9 = Fuller | first9 = R.A. | year = 2019 |title = The global distribution and trajectory of tidal flats | journal = Nature | volume = 565 | issue = 7738 | pages = 222–225 | doi = 10.1038/s41586-018-0805-8 | pmid = 30568300 | bibcode = 2019Natur.565..222M | s2cid = 56481043 }}/</ref> They are found in sheltered areas such as [[bay]]s, [[bayou]]s, [[lagoon]]s, and [[estuary|estuaries]]; they are also seen in [[freshwater]] [[lake]]s and [[salt lake|salty lakes]] (or inland seas) alike, wherein many rivers and [[Stream|creeks]] end. Mudflats may be viewed [[geology|geologically]] as exposed layers of [[bay mud]], resulting from deposition of [[estuarine]] [[silt]]s, [[clay]]s and aquatic animal [[detritus]]. Most of the sediment within a mudflat is within the [[intertidal zone]], and thus the flat is submerged and exposed approximately twice daily.

A recent global [[remote sensing]] analysis estimated that approximately 50% of the global extent of tidal flats occurs within eight countries ([[Indonesia]], [[China]], [[Australia]], [[United States]], [[Canada]], [[India]], [[Brazil]], and [[Myanmar]]) and that 44% of the world's tidal flats occur within Asia ({{convert|56,051|km2|mi2|disp=or|abbr=on}}).<ref name=Murray/> A 2022 analysis of tidal wetland losses and gains estimates that global tidal flats experienced losses of {{convert|7,000|km2|mi2|abbr=on}} between 1999 and 2019, which were largely offset by global gains of {{convert|6,700|km2|mi2|abbr=on}} over the same time period.<ref name="Murray et al. 2022">{{cite journal |last1=Murray |first1=Nicholas J. |last2=Worthington |first2=Thomas A. |last3=Bunting |first3=Pete |last4=Duce |first4=Stephanie |last5=Hagger |first5=Valerie |last6=Lovelock |first6=Catherine E. |last7=Lucas |first7=Richard |last8=Saunders |first8=Megan I. |last9=Sheaves |first9=Marcus |last10=Spalding |first10=Mark |last11=Waltham |first11=Nathan J. |last12=Lyons |first12=Mitchell B. |title=High-resolution mapping of losses and gains of Earth's tidal wetlands |journal=Science |date=13 May 2022 |volume=376 |issue=6594 |pages=744–749 |doi=10.1126/science.abm9583|pmid=35549414 |bibcode=2022Sci...376..744M |s2cid=248749118 |url=http://pure.aber.ac.uk/ws/files/50771054/abm9583_CombinedPDF_v5.pdf }}</ref>

In the past tidal flats were considered unhealthy, economically unimportant areas and were often dredged and developed into agricultural land.<ref>{{Cite web|url=http://www.mrcirl.org/marker/marker1701/0701.html|title=Dredging Indian River Lagoon Wetlands 1920 - 1950s|access-date=2011-10-28|archive-date=2013-03-20|archive-url=https://web.archive.org/web/20130320113810/http://www.mrcirl.org/marker/marker1701/0701.html|url-status=dead}}</ref> Some mudflats can be extremely treacherous to walk on. For example, the mudflats surrounding [[Anchorage, Alaska]], are made from fine glacial-silt which does not easily separate out its water, and, although seemingly solid, can quickly gel and become like [[quicksand]] when disturbed by stepping on it. Four people are known to have become stuck up to their waists and drowned when the tide came in, and many others are rescued from the Anchorage mudflats each year.<ref>[https://apnews.com/article/alaska-mud-flats-silt-drowning-96bba1b5a8a463118e3a886ae2b01499 Associated Press - Man dies on Alaskan Mudflat]</ref> 

On the [[Baltic Sea]] coast of [[Germany]] in places, mudflats are exposed not by tidal action, but by wind-action driving water away from the shallows into the sea. This kind of wind-affected mudflat is called ''[[Windwatt]]'' in German.{{cn|date=September 2022}}