what makes this topic not to end .i read up to the acquatic biomes and cant go on
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what makes this topic not to end .i read up to the acquatic biomes and cant go on
otherwise this is cool stuff very educative and interesting as well
Let's be aware, the Environment is one for us and we are all for the environment this doesn't mean that we are owners so we can do all that desire with it, in it and by it, we must all know that we are a steward of it.
Protected Areas Perhaps the method most used and most efficient way to conserve the environment, is the preservation of nature, biological and other environmental resources through the establishment and management of protected areas diversity. In fact, the first protected areas date back some three thousand years before present, when the zone concept was developed for the Royal Hunt in Asian empires where monarchs wanted to ensure full wildlife areas. More recently, in the late nineteenth century, was born an environmentalist and naturalist movement in the Western world, which resulted in the creation of the first modern national parks: Yellowstone and Yosemite, both in the United States. Since then more than 100,000 protected areas were created in the world, covering more than 12% of the land surface. Today remains the main strategy for effective conservation, strongly promoted by the Secretariat of the Convention on Biological Diversity (CBD). Now, however, is placing less emphasis on simply creating new protected areas, as it is considered more important the effective management and sustainable financing of existing protected areas.
forests are among the major parts of a biomas
Biosphere is dvided
More of our forests in West Africa without replanting.
More of our forests in West Africa are destroyed without replanted.
The biosphere can be divided into relatively large regions called biomes. A biome has a distinct climate and certain living organisms (especially vegetation) characteristic to the region and may contain many ecosystems. The key factors determining climate are average annual precipitation and temperature. These factors, in turn, depend on the geography of the region, such as the latitude and elevation of the region, and mountainous barriers.
Biomes have no distinct boundaries. Instead, there is a transition zone called an ecotone, which contains a variety of plants and animals. For example, an ecotone might be a transition region between a grassland and a desert, with species from both.
The major types of biomes include: aquatic, desert, forest, grassland and tundra.
Water covers a major portion of the earth\'s surface, so aquatic biomes contain a rich diversity of plants and animals.
Aquatic biomes can be subdivided into two basic types:
freshwater and marine.
Freshwater has a low salt concentration, usually less than 1%, and occurs in several types of regions: ponds and lakes, streams and rivers, and wetlands.
Ponds and lakes range in size, and small ponds may be seasonal. They sometimes have limited species diversity due to isolation from other water environments. They can get their water from precipitation, surface runoff, rivers, and springs.
Streams and rivers are bodies of fl_owing water moving in one general direction (i.e., downstream). Streams and rivers start at their upstream headwaters, which could be springs, snowmelt or even lakes. They continue downstream to their mouths, which may be another stream, river, lake or ocean. The environment of a stream or river may change along its length, ranging from clear, cool water near the head, to warm, sediment-rich water near the mouth. The greatest diversity of living organisms usually occurs in the middle region.
Wetlands are places of still water that support aquatic plants, such as cattails, pond lilies and cypress trees. Types of wetlands include marshes, swamps and bogs. Wetlands have the highest diversity of species with many species of birds, fur-bearing mammals, amphibians and reptiles. Some wetlands, such as salt marshes, are not freshwater regions.
Marine regions cover nearly three-fourths of the earth\'s surface. Marine bodies are salty, having approximately 35 grams of dissolved salt per liter of water (3.5 percent). Oceans are very large marine bodies that dominate the earth\'s surface and hold the largest ecosystems. They contain a rich diversity of living organisms. Ocean regions can be separated into four major zones: intertidal, pelagic, benthic and abyssal.
The intertidal zone is where the ocean meets the land. Sometimes, it is submerged and at other times exposed, depending upon waves and tides.
The pelagic zone includes the open ocean further away from land.
The benthic zone is the region below the pelagic zone, but not including the very deepest parts of the ocean. The bottom of this zone consists of sediments.
The deepest parts of the ocean are known as the abyssal zone. This zone is very cold (near freezing temperatures), and under great pressure from the overlying mass of water. Mid-ocean ridges occur on the ocean floor in abyssal zones.
Coral reefs are found in the warm, clear, shallow waters of tropical oceans around islands or along continental coastlines.
Deserts are dry areas where evaporation usually exceeds precipitation. Rainfall is low - less than 25 centimeters per year and can be highly variable and seasonal. The low humidity results in temperature extremes between day and night. Deserts can be hot or cold.
Hot deserts (e.g. the Sonovan) are very hot in the summer and have relatively high temperatures throughout the year and have seasonal rainfall.
Cold deserts (e.g. the Gobi) are characterized by cold winters and low but year-round precipitation. Deserts have relatively little vegetation and the substrate consists mostly of sand, gravel or rocks.
The transition regions between deserts and grasslands are sometimes called semiarid deserts (e.g. the Great Basin of the western United States).
Grasslands cover regions where moderate rainfall is sufficient for the growth of grasses, but not enough for stands of trees. There are two main types of grasslands: tropical grasslands (savannas) and temperate grasslands.
Tropical grasslands occur in warm climates such as Africa and very limited regions of Australia. They have a few scattered trees and shrubs, but their distinct rainy and dry seasons prevent the formation of tropical forests. Lower rainfall, more variable winter-through-summer temperatures and a near lack of trees characterize temperate grasslands.
Prairies are temperate grasslands at fairly high elevation. They may be dominated by long or short grass species. The vast prairies originally covering central North America, or the Great Plains, were the result of favorable climate conditions created by their high elevation and proximity to the Rocky Mountains. Because temperate grasslands are treeless, relatively _at and have rich soil, most have been replaced by farmland.
Forests are dominated by trees and can be divided into three types: tropical forests, temperate forests and boreal forests.
Tropical forests are always warm and wet and are found at lower latitudes. Their annual precipitation is very high, although some regions may have distinct wet and dry seasons. Tropical forests have the highest biodiversity of this biome.
Temperate forests occur at mid-latitudes (i.e. North America), and therefore have distinct seasons. Summers are warm and winters are cold. The temperate forests have suffered considerable alteration by humans, who have cleared much of the forest land for fuel, building materials and agricultural use.
Boreal forests are located in higher latitudes, like Siberia, where they are known as \"taiga.\" They have very long, cold winters and a short summer season when most of the precipitation occurs. Boreal forests represent the largest biome on the continents.
Very low temperatures, little precipitation and low biodiversity characterize tundra. Its vegetation is very simple, with virtually no trees. The tundra can be divided into two different types: arctic tundra and alpine tundra.
The arctic tundra occurs in polar regions. It has a very short summer growing season. Water collects in ponds and bogs, and the ground has a subsurface layer of permanently frozen soil known as permafrost.
Alpine tundra is found at high elevations in tall mountains. The temperatures are not as low as in the arctic tundra, and it has a longer summer growing season.
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