|
Hemistena
The cracking pearlymussel (''Hemistena lata'') is an endangered species of freshwater mussel, an aquatic bivalve mollusk in the family Unionidae. This species is native to the United States, where it remains only in Tennessee and Virginia. It was originally distributed in the Ohio River, Cumberland River and Tennessee River systems, but it has been extirpated from most of its previous range. Parmalee and Bogan reported that there were still populations in the Clinch River in Tennessee.Parmalee, P. W. and Bogan, A. E. (1998) ''The Freshwater Mussels of Tennessee''. Knoxville, TNUniversity of Tennessee Press Other populations that are known to survive are located in the Powell and Elk The elk (''Cervus canadensis''), also known as the wapiti, is one of the largest species within the deer family, Cervidae, and one of the largest terrestrial mammals in its native range of North America and Central and East Asia. The common ... Rivers. Shell description These mussel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unionidae
The Unionidae are a family of freshwater mussels, the largest in the order Unionida, the bivalve molluscs sometimes known as river mussels, or simply as unionids. The range of distribution for this family is world-wide. It is at its most diverse in North America, with about 297 recognised taxa, but China and Southeast Asia also support very diverse faunas. Freshwater mussels occupy a wide range of habitats, but most often occupy lotic waters, i.e. flowing water such as rivers, streams and creeks. Origin and early diversification The recent phylogenetic study reveals that the Unionidae most likely originated in Southeast and East Asia in the Jurassic, with the earliest expansions into North America and Africa (since the mid-Cretaceous) followed by the colonization of Europe and India (since the Paleocene). Life history Unionidae burrow into the substrate, with their posterior margins exposed. They pump water through the incurrent aperture, obtaining oxygen and food. They remove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Constantine Samuel Rafinesque
Constantine Samuel Rafinesque-Schmaltz (; October 22, 1783September 18, 1840) was a French 19th-century polymath born near Constantinople in the Ottoman Empire and self-educated in France. He traveled as a young man in the United States, ultimately settling in Ohio in 1815, where he made notable contributions to botany, zoology, and the study of prehistoric earthworks in North America. He also contributed to the study of ancient Mesoamerican linguistics, in addition to work he had already completed in Europe. Rafinesque was an eccentric and erratic genius. He was an autodidact, who excelled in various fields of knowledge, as a zoologist, botanist, writer and polyglot. He wrote prolifically on such diverse topics as anthropology, biology, geology, and linguistics, but was honored in none of these fields during his lifetime. Indeed, he was an outcast in the American scientific community whose submissions were rejected automatically by leading journals. Among his theories were th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clinch River
The Clinch River is a river that flows southwest for more than through the Great Appalachian Valley in the U.S. states of Virginia and Tennessee, gathering various tributaries, including the Powell River, before joining the Tennessee River in Kingston, Tennessee. Course The Clinch River is dammed twice: by Norris Dam, the first dam built by the Tennessee Valley Authority (TVA); and by the Melton Hill Dam, the only TVA dam with a navigation lock that is not located on the main channel of the Tennessee River. An important tributary of the Clinch River is the Powell River. The Clinch and Powell River drainage basins are separated by Powell Mountain. Tributaries entering the Clinch River below Norris Dam but above Melton Hill Dam include Coal Creek, Hinds Creek, Bull Run Creek, and Beaver Creek. Poplar Creek enters the river below the Melton Hill Dam. History A peninsula located at the mouth of the Clinch River, called Southwest Point, was the site of an early frontier fort ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molluscs Of North America
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is estimated between 60,000 and 100,000 additional species. The proportion of undescribed species is very high. Many taxa remain poorly studied. Molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. Numerous molluscs also live in freshwater and terrestrial habitats. They are highly diverse, not just in size and anatomical structure, but also in behaviour and habitat. The phylum is typically divided into 7 or 8 taxonomic classes, of which two are entirely extinct. Cephalopod molluscs, such as squid, cuttlefish, and octopuses, are among the most neurologically advanced of all invertebrates—and either the giant squid or the colossal squid is the largest known invertebrate species. The gastropods ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bivalves Described In 1820
Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, bivalves have no head and they lack some usual molluscan organs, like the radula and the odontophore. They include the clams, oysters, cockles, mussels, scallops, and numerous other families that live in saltwater, as well as a number of families that live in freshwater. The majority are filter feeders. The gills have evolved into ctenidia, specialised organs for feeding and breathing. Most bivalves bury themselves in sediment, where they are relatively safe from predation. Others lie on the sea floor or attach themselves to rocks or other hard surfaces. Some bivalves, such as the scallops and file shells, can swim. The shipworms bore into wood, clay, or stone and live inside these substances. The shell of a bivalve is composed of calcium c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollution
Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants. Although environmental pollution can be caused by natural events, the word pollution generally implies that the contaminants have an anthropogenic source – that is, a source created by human activities. Pollution is often classed as point source or nonpoint source pollution. In 2015, pollution killed nine million people worldwide (one in six deaths). This remained unchanged in 2019, with little real progress against pollution being identifiable. Air pollution accounted for of these earlier deaths. Major forms of pollution include air pollution, light pollution, litter, noise pollution, plastic pollution, soil contamination, radioactiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silting
Siltation, is water pollution caused by particulate terrestrial clastic material, with a particle size dominated by silt or clay. It refers both to the increased concentration of suspended sediments and to the increased accumulation (temporary or permanent) of fine sediments on bottoms where they are undesirable. Siltation is most often caused by soil erosion or sediment spill. It is sometimes referred to by the ambiguous term "sediment pollution", which can also refer to a chemical contamination of sediments accumulated on the bottom, or to pollutants bound to sediment particles. Although "siltation" is not perfectly stringent, since it also includes particle sizes other than silt, it is preferred for its lack of ambiguity. Causes The origin of the increased sediment transport into an area may be erosion on land or activities in the water. In rural areas, the erosion source is typically soil degradation by intensive or inadequate agricultural practices, leading to soil eros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mollusc Shell
The mollusc (or molluskOften spelled mollusk shell in the USA; the spelling "mollusc" are preferred by ) shell is typically a calcareous exoskeleton which encloses, supports and protects the soft parts of an animal in the phylum Mollusca, which includes snails, clams, tusk shells, and several other classes. Not all shelled molluscs live in the sea; many live on the land and in freshwater. The ancestral mollusc is thought to have had a shell, but this has subsequently been lost or reduced on some families, such as the squid, octopus, and some smaller groups such as the caudofoveata and solenogastres. Today, over 100,000 living species bear a shell; there is some dispute as to whether these shell-bearing molluscs form a monophyletic group (conchifera) or whether shell-less molluscs are interleaved into their family tree. Malacology, the scientific study of molluscs as living organisms, has a branch devoted to the study of shells, and this is called conchology—although these te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beacham Publishing Inc
Beacham is a surname. Notable people with the surname include: * Robert Beacham (or Beauchamp), founding settler of Norwalk, Connecticut *Braxton Beacham (1864-1924), Mayor of Orlando, Florida (1902) * Jack Beacham (1902-1982), English footballer * Joseph Beacham (1874-1958), American football college coach * Stephanie Beacham (born 1947), English actress * Susan Beacham (born 1958), American personal finance expert *Travis Beacham (born 1980), American screenwriter Places that begin with "Beacham" include: *Beacham Theatre (built 1921), historic cinema in Orlando, Florida constructed by Braxton Beacham See also * Beauchamp (other) * Beecham * Miller & Beacham The music publishing firm of Miller & Beacham was formed by William Miller and Joseph R. Beacham in 1853 in Baltimore, Maryland. In 1862, they purchased the Baltimore firm of John Cole. Miller had previously purchased the firm of F. D. Benteen in ..., music publishing company {{surname, Beacham English-lan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elk River (North Carolina)
Elk River may refer to: Municipalities *Elk River, California - a small community located at the edge of Eureka, California *Elk River, California, former name of Elk, Mendocino County, California * Elk River, Idaho *Elk River, Minnesota Rivers and related topography Canada *Elk River (Alberta) *Elk River (British Columbia) * Elk River (Northwest Territories), see List of rivers of the Northwest Territories * Elk River (Vancouver Island), on Vancouver Island, British Columbia ** Elk River Mountains, on Vancouver Island, British Columbia, Canada Poland * Ełk River United States *Elk River (California) *Elk River (Colorado) *Elk River (Iowa) *Elk River (Kansas) *Elk River (Maryland) *Elk River (Michigan) *Elk River (Minnesota) * Elk River (North Carolina) *Elk River (Oklahoma), a stream in Oklahoma and Missouri *Elk River (Oregon) *Elk River (Tennessee) *Elk River (Washington) * Elk River (Wisconsin) *Elk River (West Virginia) The Elk River is a tributary of the Kanawha River, l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Powell River (Virginia)
The Powell River is a 195-mile-long river in the United States that rises in Southwest Virginia and flows southwest into East Tennessee. The South Fork of the river rises in rural Wise County, Virginia, near the Laurel Grove community northwest of Norton and flows for several miles before the confluence with Roaring Fork in the Kent Junction community. From Kent Junction the river flows until it meets the North Fork of the River near Woodway, Virginia. The North Folk originates near Keokee, Virginia. The river flows past Big Stone Gap, Virginia and then runs nearly the entire length of Lee County, Virginia. It drains approximately 954 square miles (2,471 km2) in both Virginia and Tennessee before reaching its confluence with the Clinch River in the Norris Lake reservoir at the site of the town of Grantsboro. The Powell River was named for Ambrose Powell who accompanied the exploration party of Dr. Thomas Walker in the mid-18th century. Legend has it that his name app ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tennessee River
The Tennessee River is the largest tributary of the Ohio River. It is approximately long and is located in the southeastern United States in the Tennessee Valley. The river was once popularly known as the Cherokee River, among other names, as the Cherokee people had their homelands along its banks, especially in what are now East Tennessee and northern Alabama. Additionally, its tributary, the Little Tennessee River, flows into it from Western North Carolina and northeastern Georgia, where the river also was bordered by numerous Cherokee towns. Its current name is derived from the Cherokee town, ''Tanasi'', which was located on the Tennessee side of the Appalachian Mountains. Course The Tennessee River is formed at the confluence of the Holston and French Broad rivers in present-day Knoxville, Tennessee. From Knoxville, it flows southwest through East Tennessee into Chattanooga before crossing into Alabama. It travels through the Huntsville and Decatur area before rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
