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Cyclosilicates, or ring silicates, have a ratio of silicon to oxygen of 1: Andalusite has the second aluminium in five-fold coordination Al  Al  SiO 5 and sillimanite has it in four-fold coordination Al  Al  SiO 5. Ignoring inconspicuous tissue features can have consequences. Lessons from the detection of microorganisms in the deep sea and deep subsurface of the Earth. They need higher amounts of calcium, phosphorus, protein, sodium, potassium, and other minerals including iron, zinc and copper. Exercise treatment for depression:
Formulas for children with acid reflux or colic are available, though often not necessary
The purpose of added fibers is to improve the texture and taste of foods rather than to prevent or treat diseases, since the amount of added fiber is generally small . There is also a lack of studies about health benefits of added fiber. Types of fiber commonly added to foods include alginate, beta-glucan , cellulose , chitin, chitosan, fructo-oligosaccharides FOS or oligofructose, gums, hemicellulose, inulin, modified starches, pectin, polydextrose, resistant dextrins or maltodextrins and soluble corn fiber.
Common foods with added fiber include breakfast cereals, pre-prepared soups, yogurts, snacks, energy bars, powdered drinks, fruit juices and canned foods.
To date, there is no conclusive evidence that dietary fiber actually helps to prevent or treat any disease . In many studies, consuming high-fiber foods was associated with lower risk of certain diseases, but it is not clear, if the beneficial effect was due to fiber or other food ingredients, such as potassium and magnesium , lower intake of saturated fats or more physical activity and healthier life style commonly observed in individuals who consume a lot of fiber-rich foods [11,43].
Low fiber intake is a cause of constipation only in some people and is usually not the only cause . In several trials in adults with chronic constipation, dietary fiber intake was associated with the increased frequency of stools [3,6,31]. Fiber supplements, such as cellulose and psyllium , were only modestly effective [3,19,33]. In constipated children , fiber-rich diet and fiber supplements may not be always helpful and may increase abdominal pain [35,37,38].
Gastrointestinal reflux disease GERD. Dietary fiber probably insoluble may help relieve GERD symptoms . Irritable bowel syndrome IBS. According to 3 systematic reviews of studies in individuals with IBS, high fiber intake of soluble , but not insoluble, fiber may help relieve constipation, but not abdominal pain, in some, but not all, individuals; in some cases, insoluble fiber, such as wheat or corn bran, may even worsen constipation [3,34,39,44].
In several studies, psyllium husk supplements helped to prevent constipation but not diarrhea and pain [3,7]. Partially hydrolyzed guar gum may help in both constipation- and diarrhea-predominant IBS [3,8]. In interventional studies, lasting for several weeks, oat bran, barley and bean products, and viscous fiber supplements guar , pectin , psyllium were associated with decreased total and LDL cholesterol blood levels [3,19,41].
The cholesterol-lowering effect of viscous soluble fiber becomes obvious after few weeks of taking and lasts only if fiber is taken on a regular basis [12,13,14,15,16]. In one systematic review of observational studies, researchers have found an association between dietary fiber intake and lower risk of cardiovascular disease, and further an association between the intake of insoluble fiber, fiber from cereals and vegetables and lower risk of coronary heart disease .
Other studies have shown similar results [3,10,11,19]. Surprisingly, in several studies, high intake of insoluble fiber from whole grains, but not from fruits and vegetables, was associated with lower risk of diabetes type 2 [1,3,53].
Some researchers recommend consuming grams of dietary fiber both soluble and insoluble per day to individuals with diabetes 2 . There is insufficient evidence about the effect of high fiber intake on weigh loss [3,19].
While conclusions of few systematic reviews of clinical trials suggest that diet high in fiber can have a mild blood pressure-lowering effect, there seems to be insufficient evidence about a high-fiber diet as a mean of treating high blood pressure [51,52]. There is insufficient evidence about protective effect of dietary fiber on colonic cancer [3,19,21] or breast cancer .
In one study in individuals with colorectal adenomas, psyllium supplements in a dose 3. Practically all types of dietary fiber are available as over-the-counter OTC supplements.
Most doctors recommend eating fiber-rich foods, which are also typically rich in minerals and vitamins , rather than taking fiber supplements. Fiber supplements should be introduced slowly to prevent abdominal bloating or diarrhea, and always with a sufficient amount of water to prevent choking or bowel obstruction .
Fiber is not considered essential nutrients because no specific symptoms of fiber deficiency were recognized so far . You can eat some delicious whole-grain bread instead of white one, and you can add beans or lentils to salads. Shrub swamps are similar to forested swamps except that shrubby vegetation such as Buttonbush, Willow, Dogwood Cornus sp.
In fact, forested and shrub swamps are often found adjacent to one another. The soil is often water logged for much of the year and covered at times by as much as a few feet of water because this type of swamp is found along slow moving streams and in floodplains.
Mangrove swamps are a type of shrub swamp dominated by mangroves that covers vast expanses of southern Florida. Bogs are one of North America's most distinctive kinds of wetlands. They are characterized by spongy peat deposits, acidic waters and a floor covered by a thick carpet of sphagnum moss. Bogs receive all or most of their water from precipitation rather than from runoff, groundwater or streams.
As a result, bogs are low in the nutrients needed for plant growth, a condition that is enhanced by acid forming peat mosses. There are two primary ways that a bog can develop: Over time, many feet of acidic peat deposits build up in bogs of either origin. The unique and demanding physical and chemical characteristics of bogs result in the presence of plant and animal communities that demonstrate many special adaptations to low nutrient levels, waterlogged conditions, and acidic waters, such as carnivorous plants.
Bogs serve an important ecological function in preventing downstream flooding by absorbing precipitation. Bogs support some of the most interesting plants in the United States like the carnivorous Sundew and provide habitat to animals threatened by human encroachment. Bogs in the United States are mostly found in the glaciated northeast and Great Lakes regions northern bogs but also in the southeast pocosins.
Their acreage declined historically as they were drained to be used as cropland and mined for their peat, which was used as a fuel and a soil conditioner. Recently, bogs have been recognized for their role in regulating the global climate by storing large amounts of carbon in peat deposits.
Bogs are unique communities that can be destroyed in a matter of days but require hundreds, if not thousands, of years to form naturally.
Northern bogs are generally associated with low temperatures and short growing seasons where ample precipitation and high humidity cause excessive moisture to accumulate. Therefore, most bogs in the United States are found in the northern states. Northern bogs often form in old glacial lakes. They may have either considerable amounts of open water surrounded by floating vegetation or vegetation may have completely filled the lake terrestrialization.
The sphagnum peats of northern bogs cause especially acidic waters. The result is a wetland ecosystem with a very specialized and unique flora and fauna that can grow in these conditions called acidophiles. Moose, deer, and lynx are a few of the animals that can be found in northern bogs. Pocosins are densely vegetated with trees and shrubs. They are subjected to fire about every 10 to 30 years Photo by Dr. The word pocosin comes from the Algonquin Native American word for "swamp on a hill.
Usually, there is no standing water present in pocosins, but a shallow water table leaves the soil saturated for much of the year. They range in size from less than an acre to several thousand acres located between and isolated from old or existing stream systems in most instances. Because pocosins are found in broad, flat, upland areas far from large streams, they are ombrotrophic like northern bogs, meaning rain provides most of their water.
The soil itself is a mixture of peat and sand containing large amounts of charcoal from periodic burnings. These natural fires occur because pocosins periodically become very dry in the spring or summer. The fires are ecologically important because they increase the diversity of shrub types in pocosins. The most common plants are evergreen trees Loblolly Bay, Red Bay and Sweet Bay , and evergreen shrubs titi, fetterbush and zenobia. Pocosins provide important habitat for many animals, including some endangered species like the red-cockaded woodpecker.
They are especially important as the last refuge for Black Bears in coastal Virginia and North Carolina and the Red Wolf has recently been reintroduced in North Carolina pocosins. Habitat is the most valuable function of Pocosins. Some pocosins are very large and difficult to develop, and so they remain largely undisturbed. As a result, they are a haven for species adapted to living in unaltered forests.
As more and more land is developed in the Eastern United States, pocosins are becoming ever more valuable refuges for wildlife. The Sweet Pitcher Plant Sarracenia rubra is one of the carnivorous plants found in pocosins. The slow movement of water through the dense organic matter in pocosins removes excess nutrients deposited by rainwater. The same organic matter also acidifies the water. This very pure water is slowly released to estuaries, where it helps to maintain the proper salinity, nutrients and acidity.
This process is important to help maintain healthy fish populations important to both commerce and recreation. Pocosins are also sources of valuable timber and fuel, but these uses can harm or destroy pocosins if they are not carried out responsibly. Historically, pocosins were mostly threatened by agriculture. Today, timber harvesting, peat mining, and phosphate mining join agriculture as the biggest threats to the remaining undisturbed pocosins.
Fens, like bogs, are peatlands, but because they are fed by groundwater they are not so acidic as bogs. Fens, are peat-forming wetlands that receive nutrients from sources other than precipitation: Fens differ from bogs because they are less acidic and have higher nutrient levels. Therefore, they are able to support a much more diverse plant and animal community. These systems are often covered by grasses, sedges, rushes and wildflowers.
Some fens are characterized by parallel ridges of vegetation separated by less productive hollows. The ridges of these patterned fens form perpendicular to the downslope direction of water movement. Over time, peat may build up and separate the fen from its groundwater supply. When this happens, the fen receives fewer nutrients and may become a bog. Like bogs, fens are mostly a northern hemisphere phenomenon -- occurring in the northeastern United States, the Great Lakes region, the Rocky Mountains and much of Canada -- and are generally associated with low temperatures and short growing seasons, where ample precipitation and high humidity cause excessive moisture to accumulate.
Fens, like bogs, provide important benefits in a watershed, including preventing or reducing the risk of floods, improving water quality and providing habitat for unique plant and animal communities. Like most peatlands, fens experienced a decline in acreage at a rate of about eight percent from to , mostly from mining and draining for cropland, fuel and fertilizer. Because of the large historical loss of this ecosystem type, remaining fens are that much more rare, and it is crucial to protect them.
It is important to recognize that while mining and draining these ecosystems provide resources for people, up to 10, years are required to form a fen naturally. Contact Us to ask a question, provide feedback, or report a problem.
Jump to main content. An official website of the United States government. Common Cattail Typha latifolia is a freshwater and estuarine marsh species.
Muskrat Ondatra zibethicus next to its house in a cattail-dominated marsh. Mink Mustela vison , a predator of the muskrat. The Clapper Rail of the saltmarshes, which is more commonly heard than seen. The insects that pollinate it are attracted by its odor, which resembles decaying flesh. Prothonotary Warblers Protonotaria citrea are found in southern swamplands. Status Due to the nutrient-rich soils present in swamps, many of these fertile woodlands have been drained and cleared for agriculture and other development.
Top of Page Swamps frequently support highly diverse vegetation because of the many layers of vegetation present: Button bush Cephalanthus occidentalis is found only in shrub swamps.