|
Garden Island (Launceston)
Garden Island is a tied island from Clarence Point, near the mouth of the Tamar River in Tasmania. It is accessed by a dirt road off Bevic Road, which runs between West Tamar Highway, Kelso and Clarence Point Road. This large area is owned by TasPorts. Garden Island is surrounded on all sides by the Tamar River, an estuary which has been excavated to provide a channel for shipping. The backfill from this dredging was moved towards the shore, and provided easier access by connecting the island. There are no facilities of any type on the island, but it provides productive seawater fishing spots, and a flat and open scenic lookout. There are also plenty of oysters in the estuary, but toxic levels of copper, zinc and cadmium Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, silvery-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Like zinc, it demonstrates oxidation state +2 in most of ... have b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tied Island
Tied islands, or land-tied islands as they are often known, are landforms consisting of an island that is connected to mainland or another island only by a tombolo: a spit of beach materials connected to land at both ends. St Ninian's Isle in the Shetland Islands off the north coast of Scotland is an example since it was once an island but is now linked to the mainland. Other examples include Maury Island, Washington, in the Puget Sound, Coronado, California; and Nahant, Massachusetts in the United States; Barrenjoey, New South Wales, in Australia; Paratutae Island, in New Zealand; Mount Hakodatein Japan, Howth Head, in Ireland; Wedge Island, in Western Australia; Cheung Chau, in Hong Kong; and Davaar Island, Campbeltown, Scotland. The Isle of Portland, in England, is also described as a tied island, but geographers now believe that Chesil Beach, which connects the island to the mainland, is a barrier beach that has moved eastwards, rather than a tombolo, which would have b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shipping
Freight transport, also referred as ''Freight Forwarding'', is the physical process of transporting Commodity, commodities and merchandise goods and cargo. The term shipping originally referred to transport by sea but in American English, it has been extended to refer to transport by land or air (International English: "carriage") as well. "Logistics", a term borrowed from the military environment, is also used in the same sense. Modes of shipment In 2015, 108 trillion tonne-kilometers were transported worldwide (anticipated to grow by 3.4% per year until 2050 (128 Trillion in 2020)): 70% by sea, 18% by road, 9% by rail, 2% by inland waterways and less than 0.25% by air. Grounds Land or "ground" shipping can be made by train or by truck (British English: lorry). In air and sea shipments, ground transport is required to take the cargo from its place of origin to the airport or seaport and then to its destination because it is not always possible to establish a production f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cadmium Poisoning
Cadmium is a naturally occurring toxic metal with common exposure in industrial workplaces, plant soils, and from smoking. Due to its low permissible exposure in humans, overexposure may occur even in situations where trace quantities of cadmium are found. Cadmium is used extensively in electroplating, although the nature of the operation does not generally lead to overexposure. Cadmium is also found in some industrial paints and may represent a hazard when sprayed. Operations involving removal of cadmium paints by scraping or blasting may pose a significant hazard. The primary use of cadmium is in the manufacturing of NiCd rechargeable batteries. The primary source for cadmium is as a byproduct of refining zinc metal. Exposures to cadmium are addressed in specific standards for the general industry, shipyard employment, the construction industry, and the agricultural industry. Signs and symptoms Acute Acute exposure to cadmium fumes may cause flu-like symptoms including chi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Toxicity
Zinc toxicity is a medical condition involving an overdose on, or toxic overexposure to, zinc. Such toxicity levels have been seen to occur at ingestion of greater than 50 mg of zinc. Excessive absorption of zinc can suppress copper and iron absorption. The free zinc ion in solution is highly toxic to bacteria, plants, invertebrates, and even vertebrate fish. Zinc is an essential trace metal with very low toxicity in humans. Signs and symptoms Following an oral intake of extremely high doses of zinc (where 300 mg Zn/d – 20 times the US Recommended Dietary Allowance, RDA – is a "low intake" overdose), nausea, vomiting, pain, cramps, and diarrhea may occur. There is evidence of induced copper deficiency, alterations of blood lipoprotein levels, increased levels of Low-density lipoprotein, LDL, and decreased levels of High-density lipoprotein, HDL at long-term intakes of 100 mg Zn/d. The USDA Recommended Dietary Allowance, RDA is 15 mg Zn/d. Ther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper Toxicity
Copper toxicity (or Copperiedus) is a type of metal poisoning caused by an excess of copper in the body. Copperiedus could occur from consuming excess copper salts, but most commonly it is the result of the genetic condition Wilson's disease and Menke's disease, which are associated with mismanaged transport and storage of copper ions. Copper is essential to human health as it is a component of many proteins. Chronic toxicity by copper is "rare". The suggested safe level of copper in drinking water for humans varies depending on the source, but tends to be pegged at 1.3 mg/L. So low is the toxicity of copper that copper(II) sulfate is a routine reagent in undergraduate chemistry laboratories. Signs and symptoms Acute symptoms of copper poisoning by ingestion include vomiting, hematemesis (vomiting of blood), hypotension (low blood pressure), melena (black "tarry" feces), coma, jaundice (yellowish pigmentation of the skin), and gastrointestinal distress. Individuals with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oysters
Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species, the valves are highly calcified, and many are somewhat irregular in shape. Many, but not all oysters are in the superfamily Ostreoidea. Some types of oysters are commonly consumed (cooked or raw), and in some locales are regarded as a delicacy. Some types of pearl oysters are harvested for the pearl produced within the mantle. Windowpane oysters are harvested for their translucent shells, which are used to make various kinds of decorative objects. Etymology The word ''oyster'' comes from Old French , and first appeared in English during the 14th century. The French derived from the Latin , the feminine form of , which is the latinisation of the Ancient Greek () 'oyster'. Compare () 'bone'. Types True oysters True oysters are members of the family Ostreidae. This family includes the edible oysters, which mainly belong t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fishing
Fishing is the activity of trying to catch fish. Fish are often caught as wildlife from the natural environment, but may also be caught from stocked bodies of water such as ponds, canals, park wetlands and reservoirs. Fishing techniques include hand-gathering, spearing, netting, angling, shooting and trapping, as well as more destructive and often illegal techniques such as electrocution, blasting and poisoning. The term fishing broadly includes catching aquatic animals other than fish, such as crustaceans ( shrimp/ lobsters/crabs), shellfish, cephalopods (octopus/squid) and echinoderms ( starfish/ sea urchins). The term is not normally applied to harvesting fish raised in controlled cultivations ( fish farming). Nor is it normally applied to hunting aquatic mammals, where terms like whaling and sealing are used instead. Fishing has been an important part of human culture since hunter-gatherer times, and is one of the few food production activities that have persisted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seawater
Seawater, or salt water, is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5% (35 g/L, 35 ppt, 600 mM). This means that every kilogram (roughly one liter by volume) of seawater has approximately of dissolved salts (predominantly sodium () and chloride () ions). The average density at the surface is 1.025 kg/L. Seawater is denser than both fresh water and pure water (density 1.0 kg/L at ) because the dissolved salts increase the mass by a larger proportion than the volume. The freezing point of seawater decreases as salt concentration increases. At typical salinity, it freezes at about . The coldest seawater still in the liquid state ever recorded was found in 2010, in a stream under an Antarctic glacier: the measured temperature was . Seawater pH is typically limited to a range between 7.5 and 8.4. However, there is no universally accepted reference pH-scale for seawater and the difference between measurement ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dredging
Dredging is the excavation of material from a water environment. Possible reasons for dredging include improving existing water features; reshaping land and water features to alter drainage, navigability, and commercial use; constructing dams, dikes, and other controls for streams and shorelines; and recovering valuable mineral deposits or marine life having commercial value. In all but a few situations the excavation is undertaken by a specialist floating plant, known as a dredger. Dredging is carried out in many different locations and for many different purposes, but the main objectives are usually to recover material of value or use, or to create a greater depth of water. Dredges have been classified as suction or mechanical. Dredging has significant environmental impacts: it can disturb marine sediments, leading to both short- and long-term water pollution, destroy important seabed ecosystems, and can release human-sourced toxins captured in the sediment. Description ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Channel (geography)
In physical geography, a channel is a type of landform consisting of the outline of a path of relatively shallow and narrow body of water or of other fluids (e.g., lava), most commonly the confine of a river, river delta or strait. The word is cognate to canal, and sometimes takes this form, e.g. the Hood Canal. Formation Channel initiation refers to the site on a mountain slope where water begins to flow between identifiable banks.Bierman, R. B, David R. Montgomery (2014). Key Concepts in Geomorphology. W. H. Freeman and Company Publishers. United States. This site is referred to as the channel head and it marks an important boundary between hillslope processes and fluvial processes. The channel head is the most upslope part of a channel network and is defined by flowing water between defined identifiable banks. A channel head forms as overland flow and/or subsurface flow accumulate to a point where shear stress can overcome erosion resistance of the ground surface. Channel he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clarence Point
Clarence Point is a locality in northern Tasmania about southwest of George Town across the Tamar River. Most of its population is settled along the riverbank. Clarence Point is also the name of the regional area that includes the village, which is part of the West Tamar Municipal Area. In the , Clarence Point had a population of 226, with a median age of 56. History The area was known as Lyetta until the late 1960s, but the name “Clarence Point” was in use in the vicinity from 1835, being applied to a shoreline feature (now Ashmans Point), a property (date unknown) and a housing estate (1911). Clarence Point was gazetted as a locality in 1967. Geography The Tamar River forms the eastern, southern, and most of the northern boundaries. Road infrastructure The A7 route (Greens Beach Road) runs through from south-West to north. Route C721 (Badger Head Road) starts at an intersection with A7 on the western boundary and runs away to the north-west. Route C722 (Clarence Point R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estuary
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments and are an example of an ecotone. Estuaries are subject both to marine influences such as tides, waves, and the influx of saline water, and to fluvial influences such as flows of freshwater and sediment. The mixing of seawater and freshwater provides 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 typically classified according to their geomorphological features or to water-circulation patterns. They can have many different names, such as bays, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Seawater")
.png "Click for more on -> Dredging")
