Showing posts with label world biomes. Show all posts
Showing posts with label world biomes. Show all posts

Friday, June 8, 2012

Biodiversity

          Biodiversity 
    
          Biodiversity is the degree of variation of life forms within a given species, ecosystem, biome, or an entire planet. Biodiversity is a measure of the health of ecosystems. Biodiversity is in part a function of climate. In terrestrial habitats, tropical regions are typically rich whereas polar regions support fewer species.

       The sequel to that first biodiversity book, naturally titled Biodiversity II (Reaka-Kudla et al. 1997), documents the rapid rise of the term "biodiversity" in importance and influence. But it also traces the study of aspects of biodiversity back as far as Aristotle. To some extent, biodiversity merely offers a new, emotive, term for some older ideas and programs. In fact, "biodiversity" is now used sometimes to mean "life" or "wilderness" or other conservation values. "Biodiversity" also has served on occasion as a catch-all for "conservation" itself.
   
       The scientific literature illustrates how most any conservation activity might use the label "biodiversity". On the one hand, workers taking advantage of the acknowledged importance of the term have expanded its meaning to capture concerns at a fine scale, such as that focussing on a favourite single species. This focus might be referred to more accurately as one of "biospecifics". At the coarser scale, one important interpretation, discussed below, advocates a primary linkage of biodiversity to the maintenance of ecosystem processes — what might be called the "bio-processes" approach.
   
      The number of the problem of defining biodiversity is that it is hard to exclude anything from a concept that is taken so easily to mean "everything". Sarkar has argued that interpreting biodiversity across all biological levels, from genes to ecosystems, amounts to considering all biological entities, so that biodiversity absurdly "becomes all of biology".

     The term "biodiversity" is used in this context largely as an assumed foundation for ecosystem processes. Norton (2001) sees the process focus as replacing, not complementing, the "increasingly obsolete" inventory/items perspective of biodiversity, arguing that we "will likely move away from the inventory-of-objects approach altogether". The processes perspective is to determine how we look at biodiversity: "…applied to biodiversity policy, we can focus on the processes that have created and sustained the species and elements that currently exist, rather than on the species and elements themselves". Further, "it is reasonable to interpret advocates of biodiversity protection as valuing natural processes for their capacity to maintain support and repair damage to their parts".

Thursday, June 7, 2012

Coniferous forest biome

Coniferous forest biome
                Coniferous forest ecosystems are found in regions of the Earth that experience somewhat long and cold winters, with summer being much shorter. Thus, it is no surprise that these biomes are more common the closer one travels towards the Earth’s poles. Additionally, this biome is found high atop mountains where temperatures tend to be lower and winter tends to last longer.
             
The Coniferous Forest is a forest of Conifers. A Conifer is a tree that produces its seeds in cones.  The Pine tree is the most common example.  Conifer leaves conserve water with the thick, waxy layer that covers their leaves, also known as needles.  The vegitation in the Coniferous forest is small in size, but large enough to feed the vast herbivore population.  Most of these animals survive the brutal winters by migrating or hibernating. 
                       
Average Annual Rainfall- 14-29.5 in.
Average Temperatures in the Summer- 57.2°F
Average Temperatures in the Winter- 14°F
Temperate coniferous forest         

Temperate coniferous forest is a terrestrial biome found in temperate regions of the world with warm summers and cool winters and adequate rainfall to sustain a forest. In most temperate coniferous forests, evergreen conifers predominate, while some are a mix of conifers and broad leaf evergreen trees and/or broad leaf deciduous trees. . Coniferous forests can be found in the United States, Canada, Europe, and Asia. Many species of trees inhabit these forests including cedar, cypress, douglas-fir,pine, podocarpus, spruce, redwood and yew. The understory also contains a wide variety of herbaceous and shrub species.

Tuesday, April 10, 2012

Tundra

Tundra Biome



              In the very cold places of the world, survival isn't easy. The soil is frozen, its top surface thawing only during summer, and no trees can grow. Yet plants and animals that are adapted for the harsh conditions thrive. This biome is called tundra. Most of the world's tundra is found in the north polar region. It is called Arctic tundra. There is a small amount of tundra on parts of Antarctica that are not covered with ice. Plus, tundra is found on high altitude mountains and is called alpine tundra.


             Permafrost is the term given to frozen soil. During the winter months, permafrost reaches the surface of the tundra. It is very cold during the winter, with temperatures reaching -60 degrees Fahrenheit (-51 degrees Celsius). Very few animals are active in these harsh conditions.


              In the summer time, the tundra changes. The Sun is out almost 24 hours a day, so the tundra starts to warm up. The permafrost melts at the surface, and plant life grows. However, the permafrost only disappears for a few inches below the surface. There isn't enough soil for trees to grow, so only small plants are found in the tundra.


          At the same time, a variety of animals come out to feast on the plants. Insects come to feed on the animals, and birds appear to enjoy the insects.


Characteristics of tundra include:
  1. Extremely cold climate

  2. Low biotic diversity

  3. Simple vegetation structure

  4. Limitation of drainage

  5. Short season of growth and reproduction

  6. Energy and nutrients in the form of dead organic material

  7. Large population oscillations
Tundra is separated into two types:

Arctic tundra

                    Arctic tundra is located in the northern hemisphere, encircling the north pole and extending south to the coniferous forests of the taiga. The arctic is known for its cold, desert-like conditions. The growing season ranges from 50 to 60 days. The average winter temperature is -34° C (-30° F), but the average summer temperature is 3-12° C (37-54° F) which enables this biome to sustain life. Rainfall may vary in different regions of the arctic. Yearly precipitation, including melting snow, is 15 to 25 cm (6 to 10 inches). Soil is formed slowly. A layer of permanently frozen subsoil called permafrost exists, consisting mostly of gravel and finer material. When water saturates the upper surface, bogs and ponds may form, providing moisture for plants. There are no deep root systems in the vegetation of the arctic tundra, however, there are still a wide variety of plants that are able to resist the cold climate. There are about 1,700 kinds of plants in the arctic and subarctic, and these include:
  • low shrubs, sedges, reindeer mosses, liverworts, and grasses

  • 400 varieties of flowers

  • crustose and folios lichen
                   All of the plants are adapted to sweeping winds and disturbances of the soil. Plants are short and group together to resist the cold temperatures and are protected by the snow during the winter. They can carry out photosynthesis at low temperatures and low light intensities. The growing seasons are short and most plants reproduce by budding and division rather than sexually by flowering. The fauna in the arctic is also diverse:
  • Herbivorous mammals: lemmings, voles, caribou

  • Carnivorous mammals: arctic foxes, wolves, and polar bears

  • Migratory birds: ravens, snow buntings, falcons, loons,

  • Insects: mosquitoes, flies, moths, grasshoppers

  • Fish: cod, flatfish, salmon, and trout
                  Animals are adapted to handle long, cold winters and to breed and raise young quickly in the summer. Animals such as mammals and birds also have additional insulation from fat. Many animals hibernate during the winter because food is not abundant. Another alternative is to migrate south in the winter, like birds do. Reptiles and amphibians are few or absent because of the extremely cold temperatures. Because of constant immigration and emigration, the population continually oscillates.

Alpine tundra

   
                           Alpine tundra is located on mountains throughout the world at high altitude where trees cannot grow. The growing season is approximately 180 days. The nighttime temperature is usually below freezing. Unlike the arctic tundra, the soil in the alpine is well drained. The plants are very similar to those of the arctic ones and include:
  • tussock grasses, dwarf trees, small-leafed shrubs, and heaths
Animals living in the alpine tundra are also well adapted:

  • Mammals: pikas,, mountain goats, sheep

  • Birds: grouse like birds

  • Insects: spring tails, grasshoppers ,beetles

Wednesday, May 18, 2011

World biomes


Bio geographical regions


The Earth can be divided into a series of bio geographical region or biomes,ecological communities where certain species of plant and animal coexist within particular climatic conditions.Within these broad classifications, other factor including soil richness ,altitude and humen activities such as urbanization , intensive agriculture  and deforestation of living species within each biome.

Wold biomes

          

 Read about Biodiversity: