32 résultats pour "wetland"
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Wetland.
Other plants and animals have special adaptations suited for living in a wet environment. Most emergent plants have air spaces in their stems that enable oxygen to betransported to roots that grow in sediments with no oxygen. Some of the trees that grow in swamps form a set of roots above the soil surface or above the water thatallows them to get oxygen to the lower roots. In saltwater wetlands, specialized cells can limit the amount of salt that enters a plant, or specialized organs can excrete...
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Rhode Island - geography.
C (73° F). Along the northern state line, the January mean temperature is about 1° C (about 2° F) colder than in Warwick in January. Along the ocean coast, theJanuary mean temperature is -1° C (30° F). Warm season temperatures are also influenced by the ocean and bay, so temperatures are usually cooler along the coastthan in the interior. The difference tends to be greatest in spring and early summer. Winter temperatures in Rhode Island are usually above -7° C (20° F), buttemperatures colder by...
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Rhode Island - USA History.
C (73° F). Along the northern state line, the January mean temperature is about 1° C (about 2° F) colder than in Warwick in January. Along the ocean coast, theJanuary mean temperature is -1° C (30° F). Warm season temperatures are also influenced by the ocean and bay, so temperatures are usually cooler along the coastthan in the interior. The difference tends to be greatest in spring and early summer. Winter temperatures in Rhode Island are usually above -7° C (20° F), buttemperatures colder by...
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Duck - biology.
from water. When ducks feed they push their tongue against the top of their mouth to squeeze water through the lamellae, leaving the food behind. Mergansers arefish-eating ducks with slender bills that are notched on the edges like the blade of a saw. These saw-toothed beaks help the ducks catch and hold their slippery prey. VI COURTSHIP AND REPRODUCTION Ducks form pairs long enough to mate, but most species find new mates each year. In a few species, including buffleheads and whistling ducks,...
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Water Pollution.
Cryptosporidium in the water supply of Milwaukee, Wisconsin, sickened more than 400,000 people and killed more than 100. H Thermal Pollution Water is often drawn from rivers, lakes, or the ocean for use as a coolant in factories and power plants. The water is usually returned to the source warmer than when itwas taken. Even small temperature changes in a body of water can drive away the fish and other species that were originally present, and attract other species in placeof them. Thermal pol...
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River.
IV RIVER PATTERNS River patterns, or general shapes, depend on the geologic zone and the climate of the location. There are four river patterns: meandering, braided, anastomosing, andstraight. A meandering pattern follows a winding, turning course. A braided pattern has connected channels that resemble a hair braid. An anastomosing river patterncombines features of the meandering and braided patterns. Some river patterns are simply straight channels. Meandering and braided are the most common...
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River - Geography.
IV RIVER PATTERNS River patterns, or general shapes, depend on the geologic zone and the climate of the location. There are four river patterns: meandering, braided, anastomosing, andstraight. A meandering pattern follows a winding, turning course. A braided pattern has connected channels that resemble a hair braid. An anastomosing river patterncombines features of the meandering and braided patterns. Some river patterns are simply straight channels. Meandering and braided are the most common...
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Conservation.
cancers, Hodgkin’s disease and leukemia. Unfortunately, human activities have greatly reduced biodiversity around the world. The 20th century encompasses one of the greatest waves of extinction, orelimination of species, to occur on the planet. The greatest threat to biodiversity is loss of habitat as humans develop land for agriculture, grazing livestock, industry,and habitation. The most drastic damage has occurred in the tropical rain forests, which cover less than seven percent of the Earth’...
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Greece - country.
minerals, such as chromium, copper, uranium, and magnesium, are relatively small. Greece’s small petroleum deposits, located under the Aegean Sea near the island ofThásos, are rapidly being depleted. There are no significant reserves of natural gas. Greece’s forests, probably abundant in ancient times, have been significantly depleted. Subsequent soil erosion has made reforestation efforts difficult. Although muchof Greece’s soil is rocky and dry, the country’s mountains are interspersed with sm...
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Estonia - country.
protest the expansion of open-pit phosphorite mining in northeastern Estonia. Their success in stopping the expansion prompted further demonstrations as part of thecountry’s independence movement. Since independence Estonia has taken measures to protect the environment. The government has ratified international agreementsto reduce emissions of hazardous wastes and greenhouse gases, as well as to protect biodiversity, wetlands, and endangered species. Estonians cherish thecountryside, and 31 perc...
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Delaware - geography.
D Climate Delaware has generally hot and humid summers and mild winters. D1 Temperature In July, average daytime temperatures are usually in the upper 20°s to lower 30°sC (80°sF) or even higher. But because summer nights tend to be cooler than thedays, July averages are about 24°C (about 75°F). In addition, onshore sea breezes can reduce daytime temperatures along the coast by 3 to 6 Celsius degrees (5 to 10Fahrenheit degrees). January averages range from -1°C (31°F) at Newark, in the north, t...
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Delaware - USA History.
D Climate Delaware has generally hot and humid summers and mild winters. D1 Temperature In July, average daytime temperatures are usually in the upper 20°s to lower 30°sC (80°sF) or even higher. But because summer nights tend to be cooler than thedays, July averages are about 24°C (about 75°F). In addition, onshore sea breezes can reduce daytime temperatures along the coast by 3 to 6 Celsius degrees (5 to 10Fahrenheit degrees). January averages range from -1°C (31°F) at Newark, in the north, t...
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Austria - country.
Wildlife is generally scarce in Austria. Chamois, deer, and marmot are still present; bear, which were once abundant, are now almost completely absent. Hunting isstrictly regulated to protect the remaining species. F Environmental Issues Industrial emissions, a high volume of tourist traffic, and significant air pollution from other countries—principally the former East Germany, Slovakia, and the CzechRepublic—combine to make acid rain the major environmental problem in Austria. One-quarter of...
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South Korea - country.
forest habitat, and overhunting. The Siberian tiger has not been sighted in the wild in South Korea since the 1920s; the Asiatic black bear can still be found in someremote mountain areas. Several species of deer are indigenous to the peninsula, including the roe deer, water deer, and Siberian musk deer. The musk deer, which hasbeen overhunted for its musk glands, is legally protected as a threatened species. Smaller mammals indigenous to the peninsula include the wild boar, red fox, badger,rabb...
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Virginia (state) - geography.
C Coastline Virginia’s coastline, for both the mainland and the Eastern Shore counties, is 180 km (112 mi) long. The state’s tidal shoreline measures 5,335 km (3,315 mi), includingall bays, inlets, tidal estuaries, and other indentations. Major indentations include Chesapeake Bay; Hampton Roads, the excellent natural harbor on which are locatedNewport News, Norfolk, and Portsmouth; and the wide tidal estuaries of the lower Potomac, James, Rappahannock, and York rivers. Cape Henry, in the southe...
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Virginia (state) - USA History.
C Coastline Virginia’s coastline, for both the mainland and the Eastern Shore counties, is 180 km (112 mi) long. The state’s tidal shoreline measures 5,335 km (3,315 mi), includingall bays, inlets, tidal estuaries, and other indentations. Major indentations include Chesapeake Bay; Hampton Roads, the excellent natural harbor on which are locatedNewport News, Norfolk, and Portsmouth; and the wide tidal estuaries of the lower Potomac, James, Rappahannock, and York rivers. Cape Henry, in the southe...
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Louisiana - geography.
lakes are on the Red River and its tributaries. In addition, small oxbow lakes are numerous in the Mississippi Alluvial Plain. Oxbow lakes are formed when a river cutsthrough the neck of one of its loops, or meanders, thus establishing a shorter course and leaving the former loop as a lake separate from the river. Louisiana also hassome artificially created reservoirs. C Coastline Louisiana’s long and irregular coastline extends along the Gulf of Mexico from the Pearl River on the east to the S...
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Louisiana - USA History.
lakes are on the Red River and its tributaries. In addition, small oxbow lakes are numerous in the Mississippi Alluvial Plain. Oxbow lakes are formed when a river cutsthrough the neck of one of its loops, or meanders, thus establishing a shorter course and leaving the former loop as a lake separate from the river. Louisiana also hassome artificially created reservoirs. C Coastline Louisiana’s long and irregular coastline extends along the Gulf of Mexico from the Pearl River on the east to the S...
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Iraq - country.
The Euphrates begins in Turkey, crosses Syria, and enters Iraq at Abū Kam āl. The flow of the Euphrates into Iraq has been greatly reduced by dams built by Turkeyand Syria. The gradient of the Euphrates above the town of H īt, in west central Iraq, is steep. In the 2,640 km (1,640 mi) from its source in Turkey to H īt, the river fallsfrom 3,000 m (10,000 ft) to a low water elevation of 50 m (170 ft) above sea level, an average drop of 1 m per km (6 ft per mi). In Iraq below H īt the fall is very...
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Spain - country.
B Natural Resources Spain has a number of mineral resources. The largest known deposits are of iron ore, zinc, and lead. Spain also produces significant quantities of copper and mercury.These deposits are mined mainly in Huelva province in southwestern Spain, around Cartagena on the Mediterranean, and at various points along the Bay of Biscay inthe north. Additionally, uranium is mined in the region of Extremadura, near the Portuguese frontier, where pyrites, fluorspar, gypsum, tungsten, and po...
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Finland - country.
Productive forestland is the most valuable natural resource of Finland. Spruce, pine, and silver birch are the principal trees used to manufacture wood and pulp andpaper products. Finland lacks coal and petroleum resources and is a net importer of energy resources. However, Finland does have significant deposits of peat, which is cut from thenumerous peat bogs that cover much of the north. Peat is an important heat source for homes, and it provides about 7 percent of Finland’s electricity needs....
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Africa - history.
Africa’s other major mountainous regions occur at the northern and southern fringes of the continent. The Atlas Mountains, a system of high ranges, extend for 2,200 km(1,400 mi) across Morocco, Algeria, and Tunisia, roughly parallel to the northern coast. These ranges enclose a number of broad inland basins and plateaus. In the west, theHigh (or Grand) Atlas contains Toubkal (4,165 m/ 13,665 ft), the highest peak of the system. Toward the east, the Atlas consists of two parallel ranges: the Tell...
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Africa.
The highest elevations in Africa are found in the various ranges of East Africa. After Kilimanjaro, the next highest peaks are Mount Kenya (5,199 m/17,057 ft), north ofKilimanjaro in central Kenya; Margherita Peak (5,109 m/ 16,762 ft) in the Ruwenzori Range on the border between Uganda and the Democratic Republic of the Congo(DRC); Ras Dashen (4,620 m/ 15,157 ft) in the Ethiopian Highlands of northern Ethiopia; Mount Meru (4,565 m/ 14,977 ft), close to Kilimanjaro in Tanzania; and MountElgon (4,...
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Pollution.
One of the greatest challenges caused by air pollution is global warming, an increase in Earth’s temperature due to the buildup of certain atmospheric gases such ascarbon dioxide. With the heavy use of fossil fuels in the 20th century, atmospheric concentrations of carbon dioxide have risen dramatically. Carbon dioxide and othergases, known as greenhouse gases, reduce the escape of heat from the planet without blocking radiation coming from the Sun. Because of this greenhouse effect,average glob...
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Environment.
escape into space of the infrared energy radiated back out by Earth. This process is referred to as the greenhouse effect. These gases, primarily carbon dioxide,methane, nitrous oxide, and water vapor, insulate Earth’s surface, helping to maintain warm temperatures. Without these gases, Earth would be a frozen planet with anaverage temperature of about -18°C (about 0°F) instead of a comfortable 15°C (59°F). If the concentration of these gases rises, they trap more heat within theatmosphere, caus...
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Denmark - country.
forests, which cover just 11.6 percent of the country, include conifers (mainly fir, spruce, larch, and pine), beech, oak, birch, and ash. Several varieties of ferns andmosses common to the northern European mainland are also found. Wild animals are scarce. Natural animal life is limited to deer and small animals such as foxes,squirrels, hares, wild ducks, pheasants, and partridges. Numerous species of freshwater fish live in Denmark’s streams and lakes. F Environmental Issues Considered highly...
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Global Warming.
some of the warming influence of increasing greenhouse gases. A1 Carbon Dioxide Carbon dioxide is the second most abundant greenhouse gas, after water vapor. Carbon dioxide constantly circulates in the environment through a variety of naturalprocesses known as the carbon cycle. It is released into the atmosphere from natural processes such as eruptions of volcanoes; the respiration of animals, whichbreathe in oxygen and exhale carbon dioxide; and the burning or decay of plants and other organic...
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Guatemala - country.
C Climate The climate of Guatemala varies according to elevation, from hot coastal plains to cold mountain heights. Most of the population lives between 900 and 2,400 m (3,000and 8,000 ft) above sea level, where there are warm days and cool nights with average annual temperatures of 20°C (68°F). The coastal regions are hot and humid,with average annual temperatures of 28°C (83°F). A rainy season, from May through October, is sometimes called “winter” because it brings cloudy afternoons andlower...
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Minnesota - geography.
C Climate Minnesota’s climate is classified as humid continental because normally there is a sufficient amount of precipitation to provide at least some surplus for runoff, andbecause Minnesota’s temperature conditions are largely controlled by its location in the interior of the large landmass of North America. The result is extreme seasonaltemperature variations. The average January temperature is about -18°C (about 0°F) in the northwest and about -10°C (about 14°F) in the south, but thetherm...
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Minnesota - USA History.
C Climate Minnesota’s climate is classified as humid continental because normally there is a sufficient amount of precipitation to provide at least some surplus for runoff, andbecause Minnesota’s temperature conditions are largely controlled by its location in the interior of the large landmass of North America. The result is extreme seasonaltemperature variations. The average January temperature is about -18°C (about 0°F) in the northwest and about -10°C (about 14°F) in the south, but thetherm...
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Africa.
The highest elevations in Africa are found in the various ranges of East Africa. After Kilimanjaro, the next highest peaks are Mount Kenya (5,199 m/17,057 ft), north ofKilimanjaro in central Kenya; Margherita Peak (5,109 m/ 16,762 ft) in the Ruwenzori Range on the border between Uganda and the Democratic Republic of the Congo(DRC); Ras Dashen (4,620 m/ 15,157 ft) in the Ethiopian Highlands of northern Ethiopia; Mount Meru (4,565 m/ 14,977 ft), close to Kilimanjaro in Tanzania; and MountElgon (4,...
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Africa - Geography.
The highest elevations in Africa are found in the various ranges of East Africa. After Kilimanjaro, the next highest peaks are Mount Kenya (5,199 m/17,057 ft), north ofKilimanjaro in central Kenya; Margherita Peak (5,109 m/ 16,762 ft) in the Ruwenzori Range on the border between Uganda and the Democratic Republic of the Congo(DRC); Ras Dashen (4,620 m/ 15,157 ft) in the Ethiopian Highlands of northern Ethiopia; Mount Meru (4,565 m/ 14,977 ft), close to Kilimanjaro in Tanzania; and MountElgon (4,...