below Sea Level
The visit the ten basins with the lowest elevations below sea level - Geology.com - maps provided by Google.com. The Fens England Below Sea Level 0. By Jim Hargan on March 1, 2007. British Heritage Travel; Twitter; Facebook; Login. Login. Leave A Reply Cancel Reply. 2016-06. The Fens England Below Sea Level. Contented cattle graze in water meadows in the shadow of Ely Cathedral. Known as the “ship of the Fens,” the cathedral began as a monastery founded by St. Ethelreda in AD 6. Global sea levels are rising. This shouldn’t be news; they’ve been rising for 2. Ice Age, when glaciers covered Siberia and Canada. As it turned out, Britain was pretty awful during the last Ice Age, and people avoided it; mile- thick ice caps had something to do with it. What is the difference between above ground level and above sea level? Update Cancel. Promoted by Zeqr. What happens to water at 3000 feet below sea level? Why New Orleans is Vulnerable to Hurricanes Geologic and Historical Factors. When New Orleans was founded in 1718, none of the current city was below sea-level. Amazon.com: Below Sea Level. Interesting Finds Updated Daily. Amazon Try Prime All. BELOW THE LEVEL OF THE SEA 1993. by LES KERR. Audio CD. $2.18 used & new (4 offers). When people did start appearing about 1. Europe; the Dover- Calais ferries now float high above their paths. A lot of water has covered a lot of land since then, disrupting human societies and natural ecosystems all the way. Nearly every continent has a low- lying stretch of coast that has been affected. The United States has several: Georgia’s Sea Islands, the Florida Everglades, Louisiana’s Mississippi Delta. In England, the largest such area is called the Fens, 3. North Sea from Cambridge to Lincoln. The Fens, like the Louisiana Delta, formed over the last 1. A person might see one of these marshes as something eternal and unchanging, but this appearance is erroneous; in geological terms, these lands are recent and changing rapidly. A person might also think he’s looking at ordinary land that’s been flooded. This, too, turns out to be a serious, common and costly error. Let’s start with these errors. Daniel Defoe called the Fens “the sink of thirteen counties,” meaning that rivers drained most of Middle England into these low, flat lands. In the spring, these rivers would run in high floods, heavy with sediment. When they hit the flat Fens, they would slow down and drop the heaviest of their sediment load. These sand and clay bars would obstruct the channels and send the rivers into wide meandering patterns, perhaps doubling their length before they hit the North Sea in the Wash, a large shallow bay. Of course, the longer a river took to fall to the sea, the slower its water, and the more sediment it dropped. This left the Fens with a shifting landscape of sluggish channels choked by sediment banks both new and ancient. In between these clogs, standing water would foster rich marsh vegetation. This in turn caused the formation of peat, nearly pure plant material partially rotted to a brownish black mass, with the rotting halted by lack of oxygen in the standing water. Peat, unlike normal vegetation, will never rot as long as it stays in standing water; over eons, it will turn into coal instead. Moreover, peat will accumulate at a remarkable rate—a foot or two in a decade. Dried peat forms into burnable bricks (it smells like Scotch whisky when it burns), and because it accumulates so rapidly, a small village can stay in equilibrium with its peat fuel supply over many centuries. Yellow flag iris bloom in the water meadows of the River Great Ouse, flooded as a wildlife reserve. For the last 6. 0 centuries, sea levels have risen gradually and slowly, an oddity in a geological record otherwise filled with large sea level oscillations. Even so, the North Sea had a nasty little jump between AD 3. Europe with an extra 2 feet of water and sending its inhabitants—folk known as Angles and Saxons—fleeing (although “conquering” might be the better word) into ill- prepared Roman territories. At the start of this rise, the areas we know as the Fens were a well- settled part of Roman Britain ruled from the town of Duroliponte (Cambridge) by its native people, the Christianized Romano- Celtic Iceni. Then the sea level rose, and history’s curtain went down for two centuries. When the curtain came back up, Duroliponte and the Iceni had disappeared, and 3. German kingdom of East Anglia. The modern Fens had come into existence. Now it’s time to take on one last error: that the undrained Fens were empty wastelands of little or no economic use. This was certainly untrue by medieval times and was probably never true. Left alone, the Fens grow over with a dense, brushy scrub vegetation known locally as carr. It seems, however, that medieval Fenland vegetation consisted of vast beds of sedge and reed, with willow and grasslands in the drier spots and ponds in the wetter spots. These ecosystems are not natural; they are human- induced and must be harvested regularly to avoid the transition to carr. People were in the Fens from the start, exploiting the resources and shaping the environment. The Fenmen were a tough breed—stubbornly independent of the aristocracy, known to keep to themselves and resent outsiders. They found a good living, made better by tax avoidance, by fishing, catching waterfowl, trapping eels, coppicing willows and other marsh trees, making baskets, taking peat for fuel, and harvesting sedge and reeds. The sedge and reed harvests were economically important as high- quality thatch for roofs and were ecologically important for maintaining the Fens’ open character and abundant wildlife. Peat harvest was important in the same way, and the peat beds were left to restore themselves. In all, the Fens probably pumped as much net value into the medieval economy as the same amount of farmland. The Church owned nearly all of the Fens in this period, through a series of abbeys, monasteries and “colleges” (clerkly monasteries, with several rich ones in nearby Cambridge). Early monks liked the Fens for their solitude and set up a series of abbeys and monasteries on clay islands that rose above the general marsh. They were rewarded for their piety; wealth flowed from the Fens’ hidden resources into these abbeys. The religious foundations seem to have understood the Fens’ peculiar economy and maintained good relations with the Fenmen. They exploited the Fens’ wealth cautiously, expanding pasture and crops by drainage where convenient but making few systematic efforts. They probably knew better. The greatest of these foundations was at Ely (from Eel Island), a 7. Fens. Founded as a monastery in 6. Ely became a cathedral in 1. The massive cathedral sits as a crown around the hilltop, with the town climbing down its slopes to a delightful small quay on the River Great Ouse (pronounced, fittingly enough, ooze). Ely remains and thrives to this day, and its 1. The Fens’ other religious houses were less lucky, and few show even scant ruins above ground. For centuries the Fenmen have drawn a comfortable living from the waters and the wetlands of the Fens. With the Reformation, Henry VIII seized the great Fen foundations and gave their property to his pals and supporters—none of whom actually lived in, or knew anything about, the Fens. While the monks knew how to keep the Fenmen happy and the tithes flowing, the new owners did not. They seem to have assumed that the Fens were economically barren and didn’t notice that their Fenmen tenants had declared a permanent tax holiday. Truth be told, it took a brave and foolish man to enter the Fens with the intent of collecting money from Fenmen. This happy state for the Fenmen lasted for 1. It was Charles I who broke up the party. His continuous struggles with Parliament—which eventually led to his execution—left him strapped for cash, and he wanted to put an end to the Fens’ duty- free zone. In 1. 63. 0 the king granted the fourth Earl of Bedford the right to drain 9. Rivers Nene and Great Ouse, stretching from Ely well to the north. Bedford, along with 1. Gentlemen Adventurers, hired the Dutch engineer Cornelius Vermuyden to work on the project from 1. Stretching from Cambridge to Lincoln, Peterborough to King’s Lynn, the Fens encompass almost a million acres of man- made landscape, rich with dark topsoil and a labyrinth of tranquil waterways abundant in wildlife. Wind- driven pumps proved an ineffective means of draining the vast wetlands. The last surviving windmill pump in working order operates at the National Trust’s preserve of Wicken Fen just northeast of Cambridge. Vermuyden understood that the flooding rivers clogged the Fens with deposits and set about fixing that by straightening their channels. A straightened river would rush its flood- waters right past the Fenlands, scour its channel and dump its sediment harmlessly into the Wash. In the largest of many projects, Vermuyden diverted the Great Ouse into two parallel channels running straight as a ruler—an amazing flood control structure 2. When floods became too great for the two channels, the mile space between them would store the excess waters. At the end of their 2. Ouse at the start of tidal waters, where a sluice could hold them back at high tide and release them at low tide to scour the channel. This part of Vermuyden’s scheme worked—and continues to work, although Vermuyden’s original sluice collapsed after 5. Vermuyden, however, assumed that the local fields could be easily drained into this and similar channels by gravity. In this he was mistaken, even though the black, water- logged “soil” of his era was high enough. That wasn’t soil, though, it was peat. It had built up, as it always does, and would rot away as soon as it was drained and exposed to air. Within a few decades, the fields had sunk below Vermuyden’s drains. By the early 1. 8th century, the Fens were once again flooded. Sitting on a limestone outcrop some 7. Ely takes its name, appropriately enough, from Eel Island. While the methods and tools have changed over the years, from early medieval times the Fens have been a managed landscape and ecosystem. Landowners were in a bind. They had spent vast sums on drainage and had enjoyed a tantalizingly brief period of high agricultural returns. To fix things, they paid increasingly high property taxes to support the drains, and they purchased “wind engines” to pump their excess water uphill into them. This didn’t do the trick; windmills were a lousy pumping technology. A single windmill pump cost a mammoth £8. One windmill could only raise water about 6 feet, so several of them might be needed in series to get the water up to the drain. While a big windmill could produce a respectable 4.
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