giant swamps

[spidermilk]

I was thinking about what it would be like to have a giant inland swamp in a con-world. Like the size of India. Is it possible? How could it form? I know nothing about this, and I'm interested any info you have on this subject.

[salem]

Maybe a giant ancient inland sea that was covered over then collapsed? It's pretty implausible.

[2+3 clusivity]

I think that at some point in time much of North America between the Rockies and Appalachian mountains was a shallow inland sea/swamp. Maybe there were some pretty intense mangroves . . . ?

EDIT: http://en.wikipedia.org/wiki/Western_Interior_Seaway

[Imralu]

Drainage into an inland area tends to form a lake, but with some pretty intense plant action a swamp/bog could be achieved.

[spidermilk]

I want a large inland expanse (Not India size, but huge.), in my conworld, that is mostly just a couple meters below sea level (With deviations into hills and lakes of course.), surrounded by higher elevation land. Would that lowland area turn into a giant swamp region? Sorry I know I'm just firing off questions like a toddler.

[CaesarVincens]

It's your world and it seems plausible enough to me, so go for it.

[vokzhen]

If you have a large area, adjacent to the ocean and varying just a bit above and below high tide, you might get a sequence of flooded at high tide - swampy mess as water is caught behind dikes and in depressions - flooded - swamp - flooded - swamp. But you'd expect erosion to take its toll relatively quickly, and in order for it to get to that point without erosion already having slowly chipped away at it and prevented such a thing from occurring, I'd think you'd need it to be recent, like a rapidly rising ocean level. The larger the area it's covering, the faster I'd think it would erode as the tides rush in and out. Dense plant material and lots of natural dikes would probably counter it a bit.

Flora and fauna might be be a bit odd, as they'd need to be saltwater-adapted even if the swamp area extends far inland.

Disclaimer: This is definitely armchair theorizing.

[Pabappa]

A hard soil could help. Much of Alaska consists of swamps because permafrost stays frozen and the rain that falls in summer can't penetrate through the frozen soil the way it would in a warmer climate. Much of the year, of course, the water is frozen so while it is still considered a swamp it wouldn't be habitable for most anything that we think of when we think of wetlands. Could there be a soil so hard that even in summer it is as impenetrable as ice, yet plants can still grow in it? I don't know, but it would get you a swamp as big as you want, with only the rainfall needed to keep it wet.

[CaesarVincens]

A hard soil could help. Much of Alaska consists of swamps because permafrost stays frozen and the rain that falls in summer can't penetrate through the frozen soil the way it would in a warmer climate. Much of the year, of course, the water is frozen so while it is still considered a swamp it wouldn't be habitable for most anything that we think of when we think of wetlands. Could there be a soil so hard that even in summer it is as impenetrable as ice, yet plants can still grow in it? I don't know, but it would get you a swamp as big as you want, with only the rainfall needed to keep it wet.

California Central Valley hard-pan is pretty tough, not quite impermeable, I don't think though. Clay is normally impermeable.

[CatDoom]

A hard soil could help. Much of Alaska consists of swamps because permafrost stays frozen and the rain that falls in summer can't penetrate through the frozen soil the way it would in a warmer climate. Much of the year, of course, the water is frozen so while it is still considered a swamp it wouldn't be habitable for most anything that we think of when we think of wetlands. Could there be a soil so hard that even in summer it is as impenetrable as ice, yet plants can still grow in it? I don't know, but it would get you a swamp as big as you want, with only the rainfall needed to keep it wet.

California Central Valley hard-pan is pretty tough, not quite impermeable, I don't think though. Clay is normally impermeable.

The Central Valley actually had pretty extensive wetlands before it was converted to agricultural land, including a huge, freshwater lake that was once the largest in North America west of the Mississippi. The borders of the lake were extremely marshy (hence why it was named after the Tules that grew thickly around it's circumference), and it's size and depth changed considerably by season and from year to year.

Here's one artist's conception of what California might have looked like from space circa 1850:



In addition to Tulare Lake, you can see a massive marsh where the Sacramento and San Joaquin rivers come together. Much of the area around the San Francisco Bay would be estuaries and tidal marshes as well, particularly at the northern and southern ends.

Hopefully that's useful to the OP in terms of inspiration; mostly I just really like that picture. >_>

[CaesarVincens]

A hard soil could help. Much of Alaska consists of swamps because permafrost stays frozen and the rain that falls in summer can't penetrate through the frozen soil the way it would in a warmer climate. Much of the year, of course, the water is frozen so while it is still considered a swamp it wouldn't be habitable for most anything that we think of when we think of wetlands. Could there be a soil so hard that even in summer it is as impenetrable as ice, yet plants can still grow in it? I don't know, but it would get you a swamp as big as you want, with only the rainfall needed to keep it wet.

California Central Valley hard-pan is pretty tough, not quite impermeable, I don't think though. Clay is normally impermeable.

The Central Valley actually had pretty extensive wetlands before it was converted to agricultural land, including a huge, freshwater lake that was once the largest in North America west of the Mississippi. The borders of the lake were extremely marshy (hence why it was named after the Tules that grew thickly around it's circumference), and it's size and depth changed considerably by season and from year to year.

Here's one artist's conception of what California might have looked like from space circa 1850:

[snip]

In addition to Tulare Lake, you can see a massive marsh where the Sacramento and San Joaquin rivers come together. Much of the area around the San Francisco Bay would be estuaries and tidal marshes as well, particularly at the northern and southern ends.

Hopefully that's useful to the OP in terms of inspiration; mostly I just really like that picture. >_>

True, I forget about Tule Lake. The estuary is still pretty marshy even now, but I'm sure it was even marshier before the water was diverted for agriculture.

[2+3 clusivity]

If you want to make your swamp 100% better, I give you: http://www.bbc.com/travel/slideshow/201 ... id-rainbow

[Jūnzǐ]

You might be interested in reading about the West Siberian Lowlands' wetlands:

http://www.biome-explorer.net/Wetlands/ ... lands.html

http://www.eoearth.org/view/article/150734/

Peat swamp forests of Borneo; though not phenomenally vast, are still huge.

And let's not forget the flooded forests of Amazonia, the blackwater Igapó and the whitewater Várzea.

[the duke of nuke]

Europe's contribution: the Pinsk Marshes.