An estuary is a enclosed coastal body of brackish water with one or more rivers or streams flowing into it, with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments, they are subject both to marine influences—such as tides and the influx of saline water—and to riverine influences—such as flows of fresh water and sediment. The mixing of sea water and fresh water provide high levels of nutrients both in the water column and in sediment, making estuaries among the most productive natural habitats in the world. Most existing estuaries formed during the Holocene epoch with the flooding of river-eroded or glacially scoured valleys when the sea level began to rise about 10,000–12,000 years ago. Estuaries are classified according to their geomorphological features or to water-circulation patterns, they can have many different names, such as bays, lagoons, inlets, or sounds, although some of these water bodies do not meet the above definition of an estuary and may be saline.
The banks of many estuaries are amongst the most populated areas of the world, with about 60% of the world's population living along estuaries and the coast. As a result, many estuaries suffer degradation from a variety of factors including: sedimentation from soil erosion from deforestation and other poor farming practices; the word "estuary" is derived from the Latin word aestuarium meaning tidal inlet of the sea, which in itself is derived from the term aestus, meaning tide. There have been many definitions proposed to describe an estuary; the most accepted definition is: "a semi-enclosed coastal body of water, which has a free connection with the open sea, within which sea water is measurably diluted with freshwater derived from land drainage". However, this definition excludes a number of coastal water bodies such as coastal lagoons and brackish seas. A more comprehensive definition of an estuary is "a semi-enclosed body of water connected to the sea as far as the tidal limit or the salt intrusion limit and receiving freshwater runoff.
This broad definition includes fjords, river mouths, tidal creeks. An estuary is a dynamic ecosystem having a connection to the open sea through which the sea water enters with the rhythm of the tides; the sea water entering the estuary streams. The pattern of dilution varies between different estuaries and depends on the volume of fresh water, the tidal range, the extent of evaporation of the water in the estuary. Drowned river valleys are known as coastal plain estuaries. In places where the sea level is rising relative to the land, sea water progressively penetrates into river valleys and the topography of the estuary remains similar to that of a river valley; this is the most common type of estuary in temperate climates. Well-studied estuaries include the Severn Estuary in the United Kingdom and the Ems Dollard along the Dutch-German border; the width-to-depth ratio of these estuaries is large, appearing wedge-shaped in the inner part and broadening and deepening seaward. Water depths exceed 30 m.
Examples of this type of estuary in the U. S. are the Hudson River, Chesapeake Bay, Delaware Bay along the Mid-Atlantic coast, Galveston Bay and Tampa Bay along the Gulf Coast. Bar-built estuaries are found in place where the deposition of sediment has kept pace with rising sea level so that the estuaries are shallow and separated from the sea by sand spits or barrier islands, they are common in tropical and subtropical locations. These estuaries are semi-isolated from ocean waters by barrier beaches. Formation of barrier beaches encloses the estuary, with only narrow inlets allowing contact with the ocean waters. Bar-built estuaries develop on sloping plains located along tectonically stable edges of continents and marginal sea coasts, they are extensive along the Atlantic and Gulf coasts of the U. S. in areas with active coastal deposition of sediments and where tidal ranges are less than 4 m. The barrier beaches that enclose bar-built estuaries have been developed in several ways: building up of offshore bars by wave action, in which sand from the sea floor is deposited in elongated bars parallel to the shoreline, reworking of sediment discharge from rivers by wave and wind action into beaches, overwash flats, dunes, engulfment of mainland beach ridges due to sea level rise and resulting in the breaching of the ridges and flooding of the coastal lowlands, forming shallow lagoons, elongation of barrier spits from the erosion of headlands due to the action of longshore currents, with the spits growing in the direction of the littoral drift.
Barrier beaches form in shallow water and are parallel to the shoreline, resulting in long, narrow estuaries. The average water depth is less than 5 m, exceeds 10 m. Examples of bar-built estuaries are Barnegat Bay, New Jersey. Fjords were formed where pleistocene glaciers deepened and widened existing river valleys so that they become U-shaped in cross s
The Pit River is a major river draining from northeastern California into the state's Central Valley. The Pit, the Klamath and the Columbia are the only three rivers in the U. S. that cross the Cascade Range. The longest tributary of the Sacramento River, it contributes as much as eighty percent of their combined water volume into the Shasta Lake reservoir; the main stem of the Pit River is 207 miles long, some water in the system flows 265 miles to the Sacramento River measuring from the Pit River's longest source. The Pit River drains a sparsely populated volcanic highlands area, passing through the south end of the Cascade Range in a deep canyon northeast of Redding; the river is so named because of the pits the Achumawi dug to trap game that came to water at the river. The river is a popular destination for fly fishing, rafting in its lower reaches, is used to generate hydroelectricity in the powerhouses below Fall River Mills where the Pit and Fall rivers join, at Shasta Dam, it is used extensively for irrigation and conservation purposes.
The Pit River rises in several forks in Modoc and Shasta counties in the northeastern corner of California. The 58-mile South Fork Pit River - West Valley Creek - Cedar Creek source originates just southeast of Buck Mountain in the Warner Mountains, in the extreme southeastern corner of the Modoc National Forest 9 miles west of the California–Nevada border; the South Fork is formed from the confluence of several creeks in Jess Valley 13 miles northeast of Madeline and flows west through a narrow canyon, past Likely generally north through a broad ranching valley where its waters are diverted for irrigation and waterfowl conservation via an extensive system of canals. The 30-mile long North Fork - Linnville Creek tributary begins 5 miles southeast of the town of Davis Creek, near Goose Lake, it flows south-southwest, joining the South Fork from the north near Alturas. Although Goose Lake is considered the terminal sink of an endorheic basin, it will overflow into the Pit River during floods.
The combined river flows west-southwest in a winding course across Modoc County, past Canby and through the Modoc National Forest in the narrow Stonecoal Valley Gorge. It turns south to flow past Lookout and into northern Lassen County, past Bieber, to emerge into the ranching region of Big Valley. North of Little Valley it flows into the Shasta National Forest; the river reaches Fall River Valley, where it is joined by the Fall River, fed by one of the largest freshwater spring systems in the United States. After passing through the town of Fall River Mills, the river drops over Pit River Falls enters the head of a long serpentine canyon that cuts through the southern Cascade Range, it turns south to join the Sacramento River as the eastern arm of Shasta Lake reservoir 15 miles north of Redding. Potem Creek joins the river at Potem Falls. Two major tributaries, Squaw Creek and the McCloud River, join the Pit from the north within the lake; the lower 30 miles of the river forms the longest of the five arms of Shasta Lake, formed by Shasta Dam on the Sacramento downstream from the original confluence.
Fed by significant volcanic groundwater basins that produce some of the largest contiguous freshwater spring systems in the United States, the middle and lower reaches of the Pit River exhibit a strong year-round flow, in contrast to the seasonal nature of most northern California rivers. Before Shasta Dam was built, the Pit contributed as much as 85 percent of the Sacramento River's dry-season flow as measured at Red Bluff, nearly 100 miles downstream of their confluence – making the river an important resource for irrigation, hydroelectricity; the upper reaches of the Pit above Fall River Mills are a snow-fed high desert stream with a much more seasonal hydrograph. The lowermost part of the Pit River system receives heavy winter rainfall, which contributes to streamflow between November and April. Summer low water flows drop below 2,000 cu ft/s. While conducting surveys for irrigation projects in the early 1900s, the U. S. Reclamation Service noted that the spring-fed Fall River alone contributed a year-round flow of about 1,500 cubic feet per second, from an aquifer fed in part by Mount Shasta snowmelt.
Much of this water rises at what is called "Thousand Springs" a few miles above Fall River Mills, west of Ahjumawi Lava Springs State Park. Hat Creek and Burney Creek, spring-fed from the Lassen Peak area, supplied a further 900 cubic feet per second to the Pit River; the aquifers in the Pit River basin may hold as much as 16 million acre feet in storage and are replenished by winter precipitation seeping through the watershed's porous volcanic rocks and soils. The water emerges at points of lower elevation where the surface layers encounter harder metamorphic and sedimentary rock; the U. S. Geological Survey operates a stream gage on the Pit River at Montgomery Creek, directly below Pit 7 Dam and above Shasta Lake; this gage measures streamflow from an area of 4,952 square miles, or 70 percent of the total watershed. The average streamflow between 1966 and 2012 was 4,786 cu ft/s, with a maximum of 73,000 cu ft/s recorded on January 24, 1970, after heavy rainfall. A short minimum flow of 30 cu ft/s occurred on July 12, 1975 due to construction work at Pit 7 Powerhouse r
The Mobile River is located in southern Alabama in the United States. Formed out of the confluence of the Tombigbee and Alabama rivers, the 45-mile-long river drains an area of 44,000 square miles of Alabama, with a watershed extending into Mississippi and Tennessee, its drainage basin is the fourth-largest of primary stream drainage basins in the United States. The river has provided the principal navigational access for Alabama. Since construction of the Tennessee-Tombigbee Waterway, it provides an alternative route into the Ohio River watershed; the Tombigbee and Alabama River join to form the Mobile River 50 miles northeast of Mobile, along the county line between Mobile and Baldwin counties. The combined stream flows south, in a winding course. 6 miles downstream from the confluence, the channel of the river divides, with the Mobile flowing along the western channel. The Tensaw River, a bayou of the Mobile River, flows alongside to the east, separated from 2 to 5 miles as they flow southward.
The Mobile River flows through the Mobile-Tensaw River Delta and reaches Mobile Bay on the Gulf of Mexico just east of downtown Mobile. The Mobile River Basin supported the greatest biodiversity of freshwater snail species in the world, including six genera and over 100 species that were endemic to the Mobile River Basin. During the past few decades, publications in the scientific literature have dealt with the apparent decimation of this fauna following the construction of dams within the Mobile River Basin and the inundation of extensive shoal habitats by impounded waters; this is a list of bridges and other crossings of the Mobile River from Mobile Bay upstream to its source at the confluence of the Tombigbee and Alabama rivers. Proposals for a new bridge to carry Interstate 10 over the river have been debated for several years; the Alabama Department of Transportation is conducting an environmental impact study for such a crossing and into the widening of the Jubilee Parkway, which carries Interstate 10 over Mobile Bay.
The location of this bridge is of great debate with some parties pushing for a crossing south of the current tunnels while others are opposed to anything south of the Cochrane–Africatown USA Bridge. Mobile-Tensaw River Delta Alabama River Tombigbee River List of Alabama rivers South Atlantic-Gulf Water Resource Region USGS: Mobile River Basin University of Alabama: Mobile River System Mobile River Terminal U. S. Geological Survey Geographic Names Information System: Mobile River "Mobile, a river in the southern part of Alabama"; the New Student's Reference Work. 1914
Tattnall County, Georgia
Tattnall County is a county located in the southeast portion of the U. S. state of Georgia. As of the 2010 census, the population was 25,520; the county seat is Reidsville. The county was created on December 5, 1801 from part of Montgomery County, Georgia by the Georgia General Assembly, it is located within a part of the Historic South region. According to the U. S. Census Bureau, the county has a total area of 488 square miles, of which 479 square miles is land and 8.9 square miles is water. Most of the western portion of Tattnall County, defined by a line running from Cobbtown south to Collins east to a point halfway to Bellville, south and southwest to the middle of the county's southern border, is located in the Ohoopee River sub-basin of the Altamaha River basin; the northeastern portion of the county, from Cobbtown to east of Reidsville, is located in the Canoochee River sub-basin of the Ogeechee River basin. The southeastern and southwestern parts of Tattnall County are located in the Altamaha River sub-basin of the larger river basin by the same name.
As of the census of 2000, there were 22,305 people, 7,057 households, 4,876 families residing in the county. The population density was 46 people per square mile. There were 8,578 housing units at an average density of 18 per square mile; the racial makeup of the county was 60.51% White, 31.43% Black or African American, 0.14% Native American, 0.29% Asian, 0.08% Pacific Islander, 6.64% from other races, 0.92% from two or more races. 8.44% of the population were Hispanic or Latino of any race. There were 7,057 households out of which 33.00% had children under the age of 18 living with them, 51.10% were married couples living together, 13.40% had a female householder with no husband present, 30.90% were non-families. 26.70% of all households were made up of individuals and 11.90% had someone living alone, 65 years of age or older. The average household size was 2.60 and the average family size was 3.12. In the county, the population was spread out with 22.90% under the age of 18, 11.20% from 18 to 24, 34.60% from 25 to 44, 20.00% from 45 to 64, 11.20% who were 65 years of age or older.
The median age was 34 years. For every 100 females there were 136.10 males. For every 100 females age 18 and over, there were 146.30 males. The median income for a household in the county was $28,664, the median income for a family was $35,951. Males had a median income of $28,994 versus $19,984 for females; the per capita income for the county was $13,439. About 18.60% of families and 23.90% of the population were below the poverty line, including 32.90% of those under age 18 and 20.20% of those age 65 or over. As of the 2010 United States Census, there were 25,520 people, 8,210 households, 5,568 families residing in the county; the population density was 53.2 inhabitants per square mile. There were 9,966 housing units at an average density of 20.8 per square mile. The racial makeup of the county was 62.7% white, 29.3% black or African American, 0.4% Asian, 0.3% American Indian, 0.1% Pacific islander, 6.0% from other races, 1.3% from two or more races. Those of Hispanic or Latino origin made up 9.8% of the population.
In terms of ancestry, 12.9% were Irish, 6.6% were German, 5.2% were American. Of the 8,210 households, 34.2% had children under the age of 18 living with them, 48.4% were married couples living together, 14.1% had a female householder with no husband present, 32.2% were non-families, 27.7% of all households were made up of individuals. The average household size was 2.52 and the average family size was 3.07. The median age was 36.6 years. The median income for a household in the county was $38,522 and the median income for a family was $45,601. Males had a median income of $35,240 versus $27,584 for females; the per capita income for the county was $16,742. About 14.7% of families and 21.4% of the population were below the poverty line, including 27.1% of those under age 18 and 11.9% of those age 65 or over. The Georgia Department of Corrections operates the Georgia State Prison in unincorporated Tattnall County, near Reidsville; the Tattnall Journal Sentinel Cobbtown Collins Glennville Manassas Reidsville Mendes National Register of Historic Places listings in Tattnall County, Georgia
The longleaf pine is a pine native to the Southeastern United States, found along the coastal plain from East Texas to southern Maryland, extending into northern and central Florida. It reaches a height of 30–35 m and a diameter of 0.7 m. In the past, before extensive logging, they grew to 47 m with a diameter of 1.2 m. The tree is a cultural symbol of the Southern United States, being the official state tree of Alabama and the unofficial state tree of North Carolina; the bark is thick, reddish-brown, scaly. The leaves are dark green and needle-like, occur in bundles of three, they are twisted and 20–45 cm in length. It is one of the two Southeastern U. S. pines with long needles, the other being slash pine. The cones, both female seed cones and male pollen cones, are initiated during the growing season before buds emerge. Pollen cones begin forming in their buds in July, while seed conelets are formed during a short period of time in August. Pollination occurs early the following spring, with the male cones 3–8 cm long.
The female cones mature in about 20 months from pollination. The seeds are 7–9 mm long, with a 25–40 mm wing. Longleaf pine may live to be 500 years old; when young, they grow a long taproot, 2–3 m long. They grow on well-drained sandy soil, characteristically in pure stands. Longleaf pine is known as being one of several species grouped as a southern yellow pine or longleaf yellow pine, in the past as pitch pine; the species epithet palustris is Latin for "of the marsh" and indicates its common habitat. The scientific name meaning "of marshes" is a misunderstanding on the part of Philip Miller, who described the species, after seeing longleaf pine forests with temporary winter flooding. Longleaf pine is pyrophytic. Periodic natural wildfire selects for this species by killing other trees, leading to open longleaf pine forests or savannas. New seedlings do not resemble a dark-green fountain of needles; this form is called the grass stage. During this stage, which lasts for 5–12 years, vertical growth is slow, the tree may take a number of years to grow ankle high.
After that, it makes a growth spurt if no tree canopy is above it. In the grass stage, it is resistant to low intensity fires because the terminal bud is protected from lethal heating by the packed needles. While immune to fire at this stage, the plant is quite appealing to feral pigs. Longleaf pine forests are rich in biodiversity, they are well-documented for their high levels of plant diversity, in groups including sedges, carnivorous plants, orchids. These forests provide habitat for gopher tortoises, which as keystone species, dig burrows that provide habitat for hundreds of other species of animals; the red-cockaded woodpecker is dependent on mature pine forests and is now endangered as a result of this decline. Longleaf pine seeds are large and nutritious, forming a significant food source for birds and other wildlife. Nine salamander species and 26 frog species are characteristic of pine savannas, along with 56 species of reptiles, 13 of which could be considered specialists on this habitat.
The Red Hills Region of Florida and Georgia is home to some of the best-preserved stands of longleaf pines. These forests have been burned for many decades to encourage bobwhite quail habitat in private hunting plantations. Vast forests of longleaf pine once were present along the southeastern Atlantic coast and Gulf Coast of North America, as part of the eastern savannas; these forests were the source of naval stores - resin and timber - needed by merchants and the navy for their ships. They have been cutover since for timber and replaced with faster-growing loblolly pine and slash pine, for agriculture, for urban and suburban development. Due to this deforestation and overharvesting, only about 3% of the original longleaf pine forest remains, little new is planted. Longleaf pine is available, however, at many nurseries within its range; the yellow, resinous wood is used for pulp. Boards cut years ago from virgin timber were wide, up to 1 m, a thriving salvage business obtains these boards from demolition projects to be reused as flooring in upscale homes.
The long needles are popular for use in the ancient craft of coiled basket making. The stumps and taproots of old trees become will not rot. Farmers sometimes find old buried stumps in fields in some that were cleared a century ago, these are dug up and sold as fatwood, "fat lighter", or "lighter wood", in demand as kindling for fireplaces, wood stoves, barbecue pits. In old-growth pine, the heartwood of the bole is saturated in the same way; when boards are cut from the fat lighter wood, they are heavy and will not rot, but buildings constructed of them are quite flammable and make hot fires. Th
Macon Macon–Bibb County, is a consolidated city-county located in the state of Georgia, United States. Macon lies near the geographic center of the state 85 miles south of Atlanta, hence the city's nickname "The Heart of Georgia." Located near the fall line of the Ocmulgee River, Macon is the county seat of Bibb County and had a 2017 estimated population of 152,663. Macon is the principal city of the Macon metropolitan area, which had an estimated population of 228,914 in 2017. Macon is the largest city in the Macon–Warner Robins Combined Statistical Area, a larger trading area with an estimated 420,693 residents in 2017. In a 2012 referendum, voters approved the consolidation of Macon and Bibb County, Macon became Georgia's fourth-largest city; the two governments merged on January 1, 2014. Macon is served by three interstate highways: I-16, I-75, I-475; the city has several institutions of higher education, as well as numerous museums and tourism sites. The area is served by the Herbert Smart Downtown Airport.
The mayor of Macon is Robert Reichert, a former Democratic member of the Georgia House of Representatives. Reichert was elected mayor of the newly consolidated city of Macon–Bibb, he took office on January 1, 2014. Macon was founded on the site of the Ocmulgee Old Fields, where the Creek Indians lived in the 18th century, their predecessors, the Mississippian culture, built a powerful chiefdom based on the practice of agriculture. The Mississippian culture constructed earthwork mounds for ceremonial and religious purposes; the areas along the rivers in the Southeast had been inhabited by indigenous peoples for 13,000 years before Europeans arrived. Macon developed at the site of Fort Benjamin Hawkins, built in 1809 at the fall line of the Ocmulgee River to protect the community and to establish a trading post with Native Americans; the fort was named in honor of Benjamin Hawkins, Superintendent of Indian Affairs for the Southeast territory south of the Ohio River for over 20 years. He was married to a Creek woman.
This was the most inland point of navigation on the river from the Low Country. President Thomas Jefferson forced the Creek to cede their lands east of the Ocmulgee River and ordered the fort built. Fort Hawkins guarded the Lower Creek Pathway, an extensive and well-traveled American Indian network improved by the United States as the Federal Road from Washington, D. C. to the ports of Mobile and New Orleans, Louisiana. A gathering point of the Creek and U. S. cultures for trading, it was a center of state militia and federal troops. The fort served as a major military distribution point during the War of 1812 against Great Britain and during the Creek War of 1813. Afterward, the fort was used as a trading post for several years and was garrisoned until 1821, it was decommissioned about 1828 and burned to the ground. A replica of the southeast blockhouse was built in 1938 and still stands today on a hill in east Macon. Part of the fort site is occupied by the Fort Hawkins Grammar School. In the 21st century, archeological excavations have revealed more of the fort's importance, stimulated planning for additional reconstruction of this major historical site.
As many Europeans had begun to move into the area, they renamed Fort Hawkins "Newtown." After the organization of Bibb County in 1822, the city was chartered as the county seat in 1823 and named Macon. This was in honor of the North Carolina statesman Nathaniel Macon, because many of the early residents of Georgia hailed from North Carolina; the city planners envisioned "a city within a park" and created a city of spacious streets and parks. They designated 250 acres for Central City Park, passed ordinances requiring residents to plant shade trees in their front yards; the city thrived due to its location on the Ocmulgee River. Cotton became the mainstay of Macon's early economy, based on the enslaved labor of African Americans. Macon was in the Black Belt of Georgia. Cotton steamboats, stage coaches, in 1843, a railroad increased marketing opportunities and contributed to the economic prosperity to Macon. In 1836, the Georgia Conference of the Methodist Episcopal Church founded Wesleyan College in Macon.
Wesleyan was the first college in the United States chartered to grant degrees to women. In 1855, a referendum was held to determine a capital city for Georgia. Macon came in last with 3,802 votes. During the American Civil War, Macon served as the official arsenal of the Confederacy. Camp Oglethorpe, in Macon, enlisted men, it held officers only, up to 2,300 at one time. The camp was evacuated in 1864. Macon City Hall, which served as the temporary state capitol in 1864, was converted to a hospital for wounded Confederate soldiers; the Union General William Tecumseh Sherman spared Macon on his march to the sea. His troops had sacked the nearby state capital of Milledgeville, Maconites prepared for an attack. Sherman, passed by without entering Macon; the Macon Telegraph wrote that, of the 23 companies which the city had furnished the Confederacy, only enough men survived and were fit for duty to fill five companies by the end of the war. The human toll was high; the city was taken by Union forces during