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94-552: The natural landscape is characterized by extended fens , the alluvial wetlands and marshes of the Hamme River and the Wümme River lowlands together with the glacially formed landscape Geest with typically sandy and loamy soils. Ritterhude consists of six villages, which were independent municipalities until 1974. The three large villages, Ritterhude (8.300 inhabitants), Platjenwerbe (2.500), and Ihlpohl (2.200) are direct suburbs of

188-534: A suture zone between these cratons and the Trans-Hudson Orogen . The Western Churchill and Superior cratons collided at about 1.9–1.8 Ga in the Trans-Hudson orogeny. Because of the irregular shapes of the colliding cratons, this collision trapped between them large fragments of juvenile crust, a sizable microcontinent , and island arc terranes , beneath what is now the centre of modern Hudson Bay as part of

282-512: A comparable position at 59°N on the Eurasian landmass in the Russian Far East and with a similar subarctic climate , has an annual average of −2.7 °C (27.1 °F). Vis-à-vis geographically closer Europe, contrasts stand much more extreme. Arkhangelsk at 64°N in northwestern Russia has an average of 2 °C (36 °F), while the mild continental coastline of Stockholm at 59°N on

376-718: A detailed history of the Hudson Bay basin has been reconstructed. During the majority of the Cambrian Period, this basin did not exist. Rather, this part of the Canadian Shield area was still topographically high and emergent. It was only during the later part of the Cambrian that the rising sea level of the Sauk marine transgression slowly submerged it. During the Ordovician, this part of

470-447: A distinct type of wetland, shares many biogeochemical characteristics with other wetlands. Like all wetlands, they play an important role in nutrient cycling because they are located at the interface of aerobic (oxic) and anaerobic (anoxic) environments. Most wetlands have a thin top layer of oxygenated soil in contact with the atmosphere or oxygenated surface waters. Nutrients and minerals may cycle between this oxidized top layer and

564-593: A dozen communities. Some of these were founded as trading posts in the 17th and 18th centuries by the Hudson's Bay Company, making them some of the oldest settlements in Western Canada . With the closure of the HBC posts and stores, although many are now run by The North West Company , in the second half of the 20th century, many coastal villages are now almost exclusively populated by Cree and Inuit . Two main historic sites along

658-458: A fen directly is particularly damaging because it lowers the water table. A lower water table can increase aeration and dry out peat, allowing for aerobic decomposition or burning of the organic matter in peat. Draining a fen indirectly by decreasing its water supply can be just as damaging. Disrupting groundwater flow into the fen with nearby human activities such as quarrying or residential development changes how much water and nutrients enter

752-592: A fen, especially its pH, are directly influenced by the type of rocks its groundwater supply contacts. pH is a major factor in determining fen species composition and richness, with more basic fens called "rich" and more acidic fens called "poor." Rich fens tend to be highly biodiverse and harbor a number of rare or endangered species, and biodiversity tends to decrease as the richness of fen decreases. Fens tend to be found above rocks that are rich in calcium, such as limestone . When groundwater flows past calcareous (calcium-rich) rocks like limestone ( calcium carbonate ),

846-622: A few miles south of the Arctic Circle ) as being part of the Arctic Ocean, specifically "Arctic Ocean Subdivision 9.11". Other authorities include it in the Atlantic, in part because of its greater water budget connection with that ocean. The search for a western route to Cathay and the East Indies , which had been actively pursued since the days of Christopher Columbus and John Cabot , in

940-459: A fuel. Pollutants can alter the chemistry of fens and facilitate invasion by invasive species . Common pollutants of fens include road salts, nutrients from septic tanks , and runoff of agricultural fertilizers and pesticides. Shakespeare used the term "fen-sucked" to describe the fog (literally: rising from marshes) in King Lear , when Lear says, "Infect her beauty, You fen-sucked fogs drawn by

1034-671: A gradient from poor to rich, with bogs at the poor end, extremely rich fens at the rich end, and poor fens in between. In this context, "rich" and "poor" refer to the species richness, or how biodiverse a fen or bog is. The richness of these species is strongly influenced by pH and concentrations of calcium and bicarbonate. These factors assist in identifying where along the gradient a particular fen falls. In general, rich fens are minerotrophic , or dependent on mineral-rich groundwater, while bogs are ombrotrophic , or dependent on precipitation for water and nutrients. Poor fens fall between these two. Rich fens are strongly minerotrophic; that is,

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1128-412: A large proportion of their water comes from mineral-rich ground or surface water. Fens that are more distant from surface waters such as rivers and lakes, however, are more rich than fens that are connected. This water is dominated by calcium and bicarbonate, resulting in a slightly acidic to slightly basic pH characteristic of rich fens. These conditions promote high biodiversity. Within rich fens, there

1222-582: A long time thereafter. In May 1612, Sir Thomas Button sailed from England with two ships to look for Henry Hudson, and to continue the search for the Northwest Passage to Asia. In 1668, Nonsuch reached the bay and traded for beaver pelts, leading to the creation of the Hudson's Bay Company (HBC), which still bears the historic name. The HBC negotiated a trading monopoly from the English Crown for

1316-536: A major determinant of fen biota and biogeochemistry . Fen soils are constantly inundated because the water table is at or near the surface. The result is anaerobic (oxygen-free) soils due to the slow rate at which oxygen diffuses into waterlogged soil. Anaerobic soils are ecologically unique because Earth's atmosphere is oxygenated, while most terrestrial ecosystems and surface waters are aerobic. The anaerobic conditions found in wetland soils result in reduced , rather than oxidized , soil chemistry. A hallmark of fens

1410-554: A minor amount of terrestrial fluvial sands and gravels of the Cretaceous period are preserved in the fill of a prominent ring-like depression about 325–650 km (202–404 mi) across created by the dissolution of Silurian evaporites during the Cretaceous period. From the large quantity of published geologic data that has been collected as the result of hydrocarbon exploration, academic research, and related geologic mapping ,

1504-418: A pH of approximately 5.5 to 4. Peat in poor fens tends to be thicker than that of rich fens, which cuts off vegetation access to the mineral-rich soil underneath. In addition, the thicker peat reduces the influence of mineral-rich groundwater that buffers the pH. This makes the fen more ombrotrophic, or dependent on nutrient-poor precipitation for its water and nutrients. Poor fens may also form in areas where

1598-475: A ring of subsided strata around the centre of this basin, strata representing this period of time are absent from the Hudson Bay basin and the surrounding Canadian Shield. The Precambrian Shield underlying Hudson Bay and in which Hudson Bay basin formed is composed of two Archean proto-continents, the Western Churchill and Superior cratons . These cratons are separated by a tectonic collage that forms

1692-653: A similar portion of the lowlands in Manitoba is contained in Wapusk National Park , the latter location being a significant maternity denning area for polar bears . In contrast, most of the eastern shores (the Quebec portion) form the western edge of the Canadian Shield in Quebec. The area is rocky and hilly. Its vegetation is typically boreal forest .The northern shores are tundra . Measured by shoreline, Hudson Bay

1786-601: A small amount dissolves and is carried to the fen supplied by the groundwater. When calcium carbonate dissolves, it produces bicarbonate and a calcium cation according to the following equilibrium: CaCO 3 + H 2 CO 3 ↽ − − ⇀ Ca 2 + + 2 HCO 3 − {\displaystyle {\ce {CaCO3 + H2CO3 <=> Ca^2+ + 2HCO3^-}}} where carbonic acid (H 2 CO 3 )

1880-684: A type of wetland, but its use is generally limited to the southern United States. Third, different languages use different terms to describe types of wetlands. For instance, in Russian, there is no equivalent word for the term swamp as it is typically used in North America. The result is a large number of wetland classification systems that each define wetlands and wetland types in their own way. However, many classification systems include four broad categories that most wetlands fall into: marsh , swamp, bog , and fen. While classification systems differ on

1974-551: A wetland is. Almost all of the phosphorus that arrives in a wetland does so through sediments or plant litter from other ecosystems. Along with nitrogen, phosphorus limits wetland fertility. Under basic conditions like those found in extremely rich fens, calcium will bind to phosphate anions to make calcium phosphates , which are unavailable for uptake by plants. Mosses also play a considerable role in aiding plants in phosphorus uptake by decreasing soil phosphorus stress and stimulating phosphatase activity in organisms found below

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2068-519: Is a large amount of variability. The richest fens are the extreme rich (marl) fens, where marl deposits are often build up. These are often pH 7 or greater. Rich and intermediate rich fens are generally neutral to slightly acidic, with a pH of approximately 7 to 5. Rich fens are not always very productive; at high calcium concentrations, calcium ions bind to phosphate anions, reducing the availability of phosphorus and decreasing primary production. Rich bogs with limited primary production can stabilize with

2162-470: Is a more potent greenhouse gas than carbon dioxide. Methanogenic archaea that reside in the anaerobic layers of peat combine carbon dioxide and hydrogen gas to form methane and water. This methane can then escape into the atmosphere and exert its warming effects. Peatlands dominated by brown mosses and sedges such as fens have been found to emit a greater amount of methane than Sphagnum -dominated peatlands such as bogs. Fens play an important role in

2256-625: Is a privately owned port on Hudson Bay in Churchill, Manitoba , Canada. Routes from the port connect to the North Atlantic through the Hudson Strait . As of 2008, the port had four deep-sea berths capable of handling Panamax -size vessels for the loading and unloading of grain, bulk commodities, general cargo, and tanker vessels. The port is connected to the Hudson Bay Railway , which shares

2350-408: Is a result of the ground or surface water input. Typically, this input results in higher mineral concentrations and a more basic pH than found in bogs. As peat accumulates in a fen, groundwater input can be reduced or cut off, making the fen ombrotrophic rather than minerotrophic . In this way, fens can become more acidic and transition to bogs over time. Fens can be found around the world, but

2444-419: Is abundant in peat. When the organic matter in peat is decomposed in the absence of oxygen, ammonium is produced via ammonification . In the oxidized surface layer of the wetland, this ammonium is oxidized to nitrite and nitrate by nitrification . The production of ammonium in the reduced layer and its consumption in the top oxidized layer drives upward diffusion of ammonium. Likewise, nitrate production in

2538-701: Is an inland marginal sea of the Arctic Ocean . The Hudson Strait provides a connection between the Labrador Sea and the Atlantic Ocean in the northeast, while the Foxe Channel connects Hudson Bay with the Arctic Ocean in the north. The Hudson Bay drainage basin drains a very large area, about 3,861,400 km (1,490,900 sq mi), that includes parts of southeastern Nunavut, Alberta , Saskatchewan , Ontario , Quebec , all of Manitoba , and parts of

2632-458: Is difficult for a number of reasons. First, wetlands are diverse and varied ecosystems that are not easily categorized according to inflexible definitions. They are often described as a transition between terrestrial and aquatic ecosystems with characteristics of both. This makes it difficult to delineate the exact extent of a wetland. Second, terms used to describe wetland types vary greatly by region. The term bayou , for example, describes

2726-478: Is estimated that there are approximately 1.1 million square kilometers of fens worldwide, but quantifying the extent of fens is difficult. Because wetland definitions vary regionally, not all countries define fens the same way. In addition, wetland data is not always available or of high quality. Fens are also difficult to rigidly delineate and measure, as they are located between terrestrial and aquatic ecosystems. Rigidly defining types of wetlands, including fens,

2820-420: Is greater than decomposition, which results in the accumulation of organic matter as peat. Resident mosses usually carry out decomposition within the fen, and temperate fens are often driven by plant roots' decomposition. These peat stores sequester an enormous amount of carbon. Nevertheless, it is difficult to determine whether fens net take up or emit greenhouse gases . This is because fens emit methane, which

2914-614: Is named after Henry Hudson , an Englishman sailing for the Dutch East India Company , and after whom the river that he explored in 1609 is also named . Hudson Bay encompasses 1,230,000 km (470,000 sq mi), making it the second-largest water body using the term " bay " in the world (after the Bay of Bengal ). The bay is relatively shallow and is considered an epicontinental sea , with an average depth of about 100 m (330 ft) (compared to 2,600 m (8,500 ft) in

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3008-576: Is produced by the dissolution of carbon dioxide in water. In fens, the bicarbonate anion produced in this equilibrium acts as a pH buffer, which keeps the pH of the fen relatively stable. Fens supplied by groundwater that doesn't flow through minerals and act as a buffer when dissolved tend to be more acidic. The same effect is observed when groundwater flows through minerals with low solubility, such as sand. In extreme rich fens, calcium carbonate can precipitate out of solution to form marl deposits. Calcium carbonate precipitates out of solution when

3102-404: Is that a significant portion of their water supply is derived from groundwater (minerotrophy). Because hydrology is the dominant factor in wetlands, the chemistry of the groundwater has an enormous effect on the characteristics of the fen it supplies. Groundwater chemistry, in turn, is largely determined by the geology of the rocks that the groundwater flows through. Thus, the characteristics of

3196-610: Is the Belcher Islands . The Belcher Islands are located in the centre of the Nastapoka arc. Another group includes the Ottawa Islands which are located near the eastern shore of the Hudson Bay. Hudson Bay occupies a large structural basin , known as the Hudson Bay basin, that lies within the Canadian Shield . The collection and interpretation of outcrop, seismic and drillhole data for exploration for oil and gas reservoirs within

3290-675: Is the largest bay in the world (the largest in area being the Bay of Bengal). The distinctive arculate segment on the eastern shore of Hudson Bay is referred to as the Nastapoka arc . There are many islands in Hudson Bay, mostly near the eastern coast. All the islands, including those in James Bay, are part of Nunavut and lie in the Arctic Archipelago . Several are disputed by the Cree. One group of islands

3384-654: The 20th century . The HBC's trade monopoly was abolished in 1870, by a British Order in Council called the Deed of Surrender , ceded Rupert's Land to Canada, an area of approximately 3,900,000 km (1,500,000 sq mi), as part of the Northwest Territories . In 1912, the western shore south of 60° and, following the Quebec Boundaries Extension Act, 1912 , all the eastern shore were transferred to

3478-704: The Bay of Bengal ). It is about 1,370 km (850 mi) long and 1,050 km (650 mi) wide. On the east it is connected with the Arctic Ocean ( Davis Strait ) by Hudson Strait ; on the north, with the Arctic Ocean by Foxe Basin (which is not considered part of the bay), and Fury and Hecla Strait . Hudson Bay is often considered part of the Arctic Ocean: the International Hydrographic Organization , in its 2002 working draft of Limits of Oceans and Seas , defined Hudson Bay, with its outlet extending from 62.5 to 66.5 degrees north (just

3572-525: The Canadian Arctic , estimated to consist of approximately 54,473 individuals. Hudson Bay has a lower average salinity level than that of ocean water. The main causes are the low rate of evaporation (the bay is ice-covered for much of the year), the large volume of terrestrial runoff entering the bay (about 700 km (170 cu mi) annually, the Hudson Bay watershed covering much of Canada, many rivers and streams discharging into

3666-645: The Hamme River at the 'Heerweg' from Hamburg to Bremen . The number of inhabitants increased from 52 families in the year 1568 to 89 in the year 1710. In 1757, both castle and bridge were destroyed during the Seven Years' War . Ritterhude belonged to the Prince-Archbishopric of Bremen . In 1648, the Prince-Archbishopric was transformed into the Duchy of Bremen , which was first ruled in personal union by

3760-687: The Okavango Delta in Botswana and the highland slopes in Lesotho . Fens can also be found at the colder latitudes of the Southern Hemisphere. They are found in New Zealand and southwest Argentina, but the extent is much less than that of the northern latitudes. Locally, fens are most often found at the intersection of terrestrial and aquatic ecosystems, such as the headwaters of streams and rivers. It

3854-430: The cycling of nutrients such as carbon, nitrogen, and phosphorus due to the lack of oxygen (anaerobic conditions) in waterlogged organic fen soils. Fens have historically been converted to agricultural land. Aside from such conversion, fens face a number of other threats, including peat cutting, pollution, invasive species, and nearby disturbances that lower the water table in the fen, such as quarrying. Interrupting

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3948-432: The partial pressure of carbon dioxide in the solution falls. The decrease in carbon dioxide partial pressure is caused by uptake by plants for photosynthesis or direct loss to the atmosphere. This reduces the availability of carbonic acid in solution, shifting the above equilibrium back towards the formation of calcium carbonate. The result is the precipitation of calcium carbonate and the formation of marl. Fen, being

4042-530: The American company OmniTRAX to run privately. In December 2015, OmniTRAX announced it was negotiating a sale of the port, and the associated Hudson Bay Railway, to a group of First Nations based in northern Manitoba. With no sale finalized by July 2016, OmniTRAX shut down the port and the major railroad freight operations in August 2016. The railway continued to carry cargo to supply the town of Churchill itself until

4136-588: The Canadian Shield continued to be submerged by rising sea levels except for a brief middle Ordovician marine regression . Only starting in the Late Ordovician and continuing into the Silurian did the gradual regional subsidence of this part of the Canadian Shield form the Hudson Bay basin. The formation of this basin resulted in the accumulation of black bituminous oil shale and evaporite deposits within its centre, thick basin-margin limestone and dolomite , and

4230-603: The Canadian Shield. The similarity in areal extent of the free-air gravity anomaly with the perimeter of the former Laurentide ice sheet that covered this part of Laurentia led to a long-held conclusion that this perturbation in the Earth's gravity reflected still ongoing glacial isostatic adjustment to the melting and disappearance of this ice sheet. Data collected over Canada by the Gravity Recovery and Climate Experiment (GRACE) satellite mission allowed geophysicists to isolate

4324-514: The HBC built several factories ( forts and trading posts ) along the coast at the mouth of the major rivers (such as Fort Severn ; York Factory , Churchill ; and the Prince of Wales Fort ). The strategic locations were bases for inland exploration. More importantly, they were trading posts with Indigenous peoples who came to them with furs from their trapping season. The HBC shipped the furs to Europe and continued to use some of these posts well into

4418-593: The Hudson Bay watershed , called Rupert's Land . In 1670, the English Crown granted a charter to facilitate fur trading within the Hudson Bay drainage basin . France contested this grant by sending several military expeditions to the region, but abandoned its claim in the Treaty of Utrecht (April 1713). The Treaty of Utrecht, signed on 11 April 1713, marked a significant agreement between Britain and France. The treaty

4512-413: The Hudson Bay basin found that it is filled by, at most, 2,500 m (8,200 ft) of Ordovician to Devonian limestone , dolomites, evaporites , black shales , and various clastic sedimentary rocks that overlie less than 60 m (200 ft) of Cambrian strata that consist of unfossiliferous quartz sandstones and conglomerates , overlain by sandy and stromatolitic dolomites. In addition,

4606-497: The Mainland. Northern Hudson Bay has a polar climate ( Köppen : ET ) being one of the few places in the world where this type of climate is found south of 60 °N, going farther south towards Quebec , where Inukjuak is still dominated by the tundra . From Arviat , Nunavut , to the west to the south and southeast prevails the subarctic climate (Köppen: Dfc ). This is because in the central summer months, heat waves can advance from

4700-435: The Russian port of Murmansk . The increase in ships traversing the proposed Arctic Bridge will result in an increase in accidents that will release pollutants into the environment, due to the freezing of the water in the winter cleanup will be harder and with a shorter window of time. The biggest port in the Hudson bay is the city of Churchill, which lies on the river with the same name, Churchill River. The Port of Churchill

4794-670: The Swedish and, from 1715 onwards, by the Hanoverian Crown. In 1823, the Duchy was abolished and its territory became part of the Stade Region . Fen A fen is a type of peat -accumulating wetland fed by mineral-rich ground or surface water . It is one of the main types of wetland along with marshes , swamps , and bogs . Bogs and fens, both peat-forming ecosystems , are also known as mires . The unique water chemistry of fens

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4888-663: The Trans-Hudson Orogen. The Belcher Islands are the eroded surface of the Belcher Fold Belt, which formed as a result of the tectonic compression and folding of sediments that accumulated along the margin of the Superior Craton before its collision with the Western Churchill Craton. Hudson Bay and the associated structural basin lie within the centre of a large free-air gravity anomaly that lies within

4982-401: The U.S. states of North Dakota , South Dakota , Minnesota , and Montana . Hudson Bay's southern arm is called James Bay . The Eastern Cree name for Hudson and James Bay is Wînipekw (southern dialect) or Wînipâkw (northern dialect), meaning muddy or brackish water. Lake Winnipeg is similarly named by the local Cree , as is the location for the city of Winnipeg . The bay

5076-811: The accumulation of mosses and mycorrhiza , which promote phosphorus cycling and can support the growth of new vegetation and bacteria. Brown mosses (family Amblystegiaceae ) and sedges (genus Carex ) are the dominant vegetation. However, an accumulation of mosses such as Sphagnum can lead to the acidification of the rich fen, potentially converting it into a poor fen. Compared to poor fens, rich fens have higher concentrations of bicarbonate, base cations (Na , Ca , K , Mg ), and sulfate . Poor fens are, in many ways, an intermediate between rich fens and bogs. Hydrologically, they are more similar to rich fens than to bogs, but regarding vegetation composition and chemistry, they are more similar to bogs than rich fens. They are much more acidic than their rich counterparts, with

5170-535: The adjacent provinces, but the bay and offshore islands remained part of the Northwest Territories. Starting in 1913, the bay was extensively charted by the Canadian government's CSS  Acadia to develop it for navigation. This mapping progress led to the establishment of Churchill, Manitoba, as a deep-sea port for wheat exports in 1929, after unsuccessful attempts at Port Nelson . The Port of Churchill

5264-400: The bay), and the limited connection with the Atlantic Ocean and its higher salinity. Sea ice is about three times the annual river flow into the bay, and its annual freezing and thawing significantly alters the salinity of the surface layer. Although its exact effects are not fully understood currently, the cyclonic storms in the bay are responsible for synoptic variability of salinity along

5358-400: The city of Bremen, while the three small villages Lesumstotel (900 inhabitants), Stendorf (600), and Werschenrege (400) are somewhat further away in the north of the municipality. First mention in 1182 in a document of the monastery of Osterholz . The house 'von der Hude' is being mentioned for the first time in a document in 1185. The castle 'Huda' was used in 1309 to protect the passage over

5452-445: The closure of an ancient ocean basin . The current general consensus is that it is an arcuate boundary of tectonic origin between the Belcher Fold Belt and undeformed basement of the Superior Craton created during the Trans-Hudson orogeny. This is because no credible evidence for such an impact structure has been found by regional magnetic, Bouguer gravity , or other geologic studies. However, other Earth scientists have proposed that

5546-501: The coast were York Factory and Prince of Wales Fort . Communities along the Hudson Bay coast or on islands in the bay are (all populations are as of 2016): The Hudson's Bay Company built forts as fur trade strongholds against the French or other possible invaders. One example is York Factory with angled walls to help defend the fort. In the 1950s, during the Cold War , a few sites along

5640-486: The coast. One consequence of the lower salinity of the bay is that the freezing point of the water is higher than in the rest of the world's oceans, thus decreasing the time that the bay remains ice-free. The increase of river inflows during the winter has decreased the season of sea ice by more than one month since the 1960s. The lower salinity of the bay also has effects on the distribution and prevalence of common marine life such as micro algae. Research has shown that

5734-556: The continuous input of groundwater stimulates production. Bogs , which lack this input of groundwater , have much lower primary production. Carbon from all types of wetlands, including fens, arrives mostly as organic carbon from either adjacent upland ecosystems or by photosynthesis in the wetland itself. Once in the wetland, organic carbon generally has three main fates: oxidation to CO 2 by aerobic respiration , burial as organic matter in peat, or decomposition to methane . In peatlands, including fens, primary production by plants

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5828-517: The development of extensive reefs that ringed the basin margins that were tectonically uplifted as the basin subsided. During Middle Silurian times, subsidence ceased and this basin was uplifted. It generated an emergent arch, on which reefs grew, that divided the basin into eastern and western sub-basins. During the Devonian Period, this basin filled with terrestrial red beds that interfinger with marine limestone and dolomites. Before deposition

5922-430: The entire bay is around 0 °C (32 °F) or below. In the extreme northeast, winter temperatures average as low as −29 °C (−20 °F). The Hudson Bay region has very low year-round average temperatures. The average annual temperature for Churchill at 59°N is −6 °C (21 °F) and Inukjuak, facing cool westerlies in summer at 58°N , an even colder −7 °C (19 °F). By comparison, Magadan , in

6016-521: The evidence of an Archean impact might have been masked by deformation accompanying the later formation of the Trans-Hudson orogen and regard an impact origin as a plausible possibility. The longer periods of ice-free navigation and the reduction of Arctic Ocean ice coverage have led to Russian and Canadian interest in the potential for commercial trade routes across the Arctic and into Hudson Bay. The so-called Arctic Bridge would link Churchill, Manitoba, and

6110-406: The exact criteria that define a fen, there are common characteristics that describe fens generally and imprecisely. A general definition provided by the textbook Wetlands describes a fen as "a peat-accumulating wetland that receives some drainage from surrounding mineral soil and usually supports marsh like vegetation." Three examples are presented below to illustrate more specific definitions for

6204-756: The fen. This can make the fen more ombrotrophic (dependent on precipitation), which results in acidification and a change in water chemistry. This directly impacts the habitat of these species, and many signature fen species disappear. Fens are also threatened by invasive species , fragmentation , peat cutting, and pollution. Non-native invasive species, such as the common buckthorn in North America, can invade fens and outcompete rare fen species, reducing biodiversity. Habitat fragmentation threatens fen species, especially rare or endangered species that are unable to move to nearby fens due to fragmentation. Peat cutting, while much more common in bogs, does happen in fens. Peat cut from fens has many uses, including burning as

6298-540: The flow of mineral-rich water into a fen changes the water chemistry, which can alter species richness and dry out the peat. Drier peat is more easily decomposed and can even burn. Fens are distributed around the world, but are most frequently found at the mid-high latitudes of the Northern Hemisphere. They are found throughout the temperate zone and boreal regions, but are also present in tundra and in specific environmental conditions in other regions around

6392-459: The global nitrogen cycle due to the anaerobic conditions found in their soils, which facilitate the oxidation or reduction of one form of nitrogen to another. Most nitrogen arrives in wetlands as nitrate from runoff , in organic matter from other areas, or by nitrogen fixation in the wetland. There are three main forms of nitrogen found in wetlands: nitrogen in organic matter, oxidized nitrogen ( nitrate or nitrite ), and ammonium . Nitrogen

6486-536: The gravity signal associated with glacial isostatic adjustment from longer–time scale process of mantle convection occurring beneath the Canadian Shield. Based upon this data, geophysicists and other Earth scientists concluded that the Laurentide Ice Sheet was composed of two large domes to the west and east of Hudson Bay. Modelling glacial isostatic adjustment using the GRACE data, they concluded that ≈25 to ≈45% of

6580-554: The groundwater supplying the fen flows through sediments that don't dissolve well or have low buffering capacity when dissolved. Species richness tends to be lower than that of rich fens but higher than that of bogs. Poor fens, like bogs, are dominated by Sphagnum mosses, which acidify the fen and decrease nutrient availability. One of the many threats that fens face is conversion to agricultural lands. Where climates are suitable, fens have been drained for agricultural use alongside crop production, grazing , and hay making . Draining

6674-538: The hot land and make the weather milder, with the result that the average temperature surpasses 10 °C (50 °F). The bay receives water from various surrounding rivers and currents originating from the Foxe Basin in the north, resulting in a counterclockwise overall flow. At the extreme southern tip of the extension known as James Bay arises a humid continental climate with a longer and generally hotter summer. (Köppen: Dfb ). The average annual temperature in almost

6768-473: The ice over the winter, and the crew survived onshore at the southern tip of James Bay . In the spring, as the ice receded, Henry Hudson expressed a desire to continue exploring the uncharted region. However, on 22 June 1611, the crew mutinied. They left Hudson and others adrift in a small boat. The fate of Hudson and the other men stranded with him remains undetermined. Nevertheless, there is little evidence in historical documents to suggest that they persisted for

6862-463: The last 100 years has led to decreases in the extent of the sea ice in Hudson Bay by 19.5% per decade. As well as a lengthening of the ice-free period, which was as short as four months in the late 17th century. The polar climate of Hudson Bay means it is home for a variety of polar climate animals, in the Western Hudson Bay (WHB) beluga whale population is the most significant known group in

6956-430: The latter part of the 15th century, directly resulted in the first sighting of Hudson Bay by Europeans. English explorers and colonists named Hudson Bay after Sir Henry Hudson who explored the bay beginning 2 August 1610, on his ship Discovery . On his fourth voyage to North America, Hudson worked his way around Greenland 's west coast and into the bay, mapping much of its eastern coast. Discovery became trapped in

7050-510: The line was damaged by flooding on 23 May 2017. The Port and the Hudson Bay Railway were sold to Arctic Gateway Group —a consortium of First Nations, local governments, and corporate investors—in 2018. On 9 July 2019, ships resupplying Arctic communities began stopping at the port for additional cargo, and the port began shipping grain again on 7 September 2019. The coast of Hudson Bay is extremely sparsely populated; there are only about

7144-464: The lower salinity of the Hudson Bay limits the growth of micro algae, which causes a notable change in biomass along the bay's salinity gradient. The western shores of the bay are a lowland known as the Hudson Bay Lowlands , covering 370,000 km (140,000 sq mi), and are Canada's largest continuous peatland . Much of the landform has been shaped by the actions of glaciers and

7238-410: The moss cover. Helophytes have been shown to bolster phosphorus cycling within fens, especially in fen reestablishment, due to their ability to act as a phosphorus sink, which prevents residual phosphorus in the fen from being transferred away from the it. Under normal conditions, phosphorus is held within soil as dissolved inorganic phosphorus, or phosphate , which leaves trace amounts of phosphorus in

7332-571: The northern limit of Hudson Bay as follows: A line from Nuvuk Point ( 62°21′N 78°06′W  /  62.350°N 78.100°W  / 62.350; -78.100 ) to Leyson Point, the Southeastern extreme of Southampton Island , through the Southern and Western shores of Southampton Island to its Northern extremity, thence a line to Beach Point ( 66°03′N 86°06′W  /  66.050°N 86.100°W  / 66.050; -86.100 ) on

7426-428: The observed free-air gravity anomaly was due to ongoing glacial isostatic adjustment, and the remainder likely represents longer time-scale effects of mantle convection. Earth scientists have disagreed about what created the semicircular feature known as the Nastapoka arc that forms a section of the shoreline of southeastern Hudson Bay. The Nastapoka arc forms a 155 degree curve and appears to be very circular. Noting

7520-429: The oxidized layer and nitrate consumption in the reduced layer by denitrification drives downward diffusion of nitrate. Denitrification in the reduced layer produces nitrogen gas and some nitrous oxide , which then exit the wetland to the atmosphere. Nitrous oxide is a potent greenhouse gas whose production is limited by nitrate and nitrite concentrations in fens. Nitrogen, along with phosphorus, controls how fertile

7614-562: The paucity of impact structures on Earth in relation to the Moon and Mars, Carlyle S. Beals proposed that it is possibly part of a Precambrian extraterrestrial impact structure that is comparable in size to the Mare Crisium on the Moon. In the same volume, John Tuzo Wilson commented on Beals' interpretation and alternately proposed that the Nastapoka arc may have formed as part of an extensive Precambrian continental collisional orogen, linked to

7708-410: The powerful sun, To fall and blister." Hudson Bay Hudson Bay , sometimes called Hudson's Bay (usually historically), is a large body of saltwater in northeastern Canada with a surface area of 1,230,000 km (470,000 sq mi). It is located north of Ontario , west of Quebec , northeast of Manitoba , and southeast of Nunavut , but politically entirely part of Nunavut. It

7802-442: The presence of peat. In The Biology of Peatlands fens are defined by the following criteria: A further distinction is made between open and wooded fens, where open fens have canopy cover less than 10% and wooded fens have 10–25% canopy cover. If tall shrubs or trees dominate, the wetland is instead classified as a wooded bog or swamp forest , depending on other criteria. Hydrological conditions, as seen in other wetlands, are

7896-520: The reduced layer below, undergoing oxidation and reduction reactions by the microbial communities adapted to each layer. Many important reactions take place in the reduced layer, including denitrification , manganese reduction, iron reduction, sulfate reduction, and methanogenesis . Because wetlands are hotspots for nutrient transformations and often serve as nutrient sinks, they may be constructed to treat nutrient-rich waters created by human activities. Fens are also hotspots for primary production , as

7990-573: The rest of the ecosystem. Iron is important in phosphorus cycling within fens. Iron can bind to high levels of inorganic phosphate within the fen, leading to a toxic environment and inhibition of plant growth. In iron-rich fens, the area can become vulnerable to acidification, excess nitrogen and potassium, and low water levels. Peat soils play a role in preventing the bonding of irons to phosphate by providing high levels of organic anions for iron to bind to instead of inorganic anions such as phosphate. Bogs and fens can be thought of as two ecosystems on

8084-625: The same parent company, and cargo connections are made with the Canadian National Railway system at HBR's southern terminus in The Pas . It is the only port of its size and scope in Canada that does not connect directly to the country's road system; all goods shipped overland to and from the port must travel by rail. The port was originally owned by the Government of Canada but was sold in 1997 to

8178-457: The shore of an analogous large hyposaline marine inlet – the Baltic Sea – has an annual average of 8 °C (46 °F). Water temperature peaks at 8–9 °C (46–48 °F) on the western side of the bay in late summer. It is largely frozen over from mid-December to mid-June, when it usually clears from its eastern end westwards and southwards. A steady increase in regional temperatures over

8272-504: The shrinkage of the bay over long periods of time. The coastal area, located in a region characterized by permanently frozen layers of soil, known as permafrost , is a low-lying wetland that receives water from lakes and fast-flowing rivers. Signs of numerous former beachfronts can be seen far inland from the current shore. A large portion of the lowlands in the province of Ontario is part of the Polar Bear Provincial Park , and

8366-538: The term fen . In the Canadian Wetland Classification System, fens are defined by six characteristics: In the textbook Wetland Ecology: Principles and Conservation , Paul A. Keddy offers a somewhat simpler definition of a fen as "a wetland that is usually dominated by sedges and grasses rooted in shallow peat, often with considerable groundwater movement, and with pH greater than 6." This definition differentiates fens from swamps and marshes by

8460-430: The vast majority are located at the mid to high latitudes of the Northern Hemisphere. They are dominated by sedges and mosses , particularly graminoids that may be rarely found elsewhere, such as the sedge species Carex exilis . Fens are highly biodiverse ecosystems and often serve as habitats for endangered or rare species, with species composition changing with water chemistry. They also play important roles in

8554-636: The world. In the United States, fens are most common in the Midwest and Northeast, but can be found across the country. In Canada, fens are most frequent in the lowlands near Hudson Bay and James Bay , but can also be found across the country. Fens are also spread across the northern latitudes of Eurasia, including Britain and Ireland, as well as Japan, but east-central Europe is especially rich in fens. Further south, fens are much rarer, but do exist under specific conditions. In Africa, fens have been found in

8648-567: Was an important shipping link for trade with Europe and Russia until its closure in 2016 by owner OmniTRAX . The port and the Hudson Bay Railway were then sold to the Arctic Gateway Group —a consortium of First Nations , local governments, and corporate investors—in 2018. On 9 July 2019, ships resupplying Arctic communities began stopping at the port for additional cargo, and the port began shipping grain again on 7 September 2019. The International Hydrographic Organization defines

8742-627: Was negotiated in Utrecht, Netherlands, and marked a crucial stage in the conclusion of the War of the Spanish Succession . Its provisions had a significant impact in shaping the postwar landscape and establishing a new order in both Europe and North America. French concessions in North America as outlined in the Treaty of Utrecht included: Hudson Bay region, Nova Scotia , and Newfoundland . During this period,

8836-454: Was terminated by marine regression, Upper Devonian black bituminous shale accumulated in the south-east of the basin. The remaining history of the Hudson Bay basin is largely unknown as a major unconformity separates Upper Devonian strata from glacial deposits of the Pleistocene . Except for poorly known terrestrial Cretaceous fluvial sands and gravels that are preserved as the fills of

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