The Earth Story

While the car commercial part isn't particularly fun, here's a drive across some amazing landscapes in Kazakhstan.

World Biomes

Biogeography is the scientific study of the way plants and animals are distributed across the globe. Because climate and soil determine which plants thrive in a particular region, similar types of vegetation, as well as the animals associated with them, occur in places with climates that are similar. These places, occupying large areas and identified by their vegetation types, are known as biomes. For example, the belt of mainly evergreen coniferous forests that runs across Canada and northern Eurasia constitutes a biome known as boreal forest in North America and taiga in Russia. The character of this forest is essentially the same throughout the biome, but the plant and animals species found there vary. There are twelve biomes in the world. Although general vegetation types can identify biomes, the vegetation in any biome is in fact quite varied because of a number of local differences in land use and environment. Tropical biomes occur between the tropics of Cancer (north) and Capricorn (south). Temperate biomes can be found in temperate regions, and polar biomes are located near the poles. Other biomes are more difficult to define precisely, because not all plant communities have clear boundaries. The range of plants in each biome makes it possible to draw the boundaries in different ways.

Around the poles, the polar ice biome supports no plant life. The climate is exceedingly harsh and there is neither soil nor liquid water at the surface. Bordering the polar ice is the tundra biome, where the ground is exposed and the temperature rises above freezing for a short time in summer. Along its edges, tundra gives way to boreal forest or taiga. Tundra and boreal forest are mainly confined to the Northern Hemisphere, because there is little land at the correct latitude in the Southern Hemisphere. Closer to the equator, deciduous trees become more common among the conifers of the boreal forest. The biome changes and temperate deciduous forest becomes more widespread. This biome is restricted to the continental regions with moist climates, while temperate rain forest is found only in the wettest regions.

As climates grow hotter and drier, the biome changes again. Temperate grassland, the prairies, steppes, pampas and veld, replace the temperature deciduous forest. In a few parts of the world there is a biome typical of Mediterranean climates, dominated by dry woodlands and chaparral shrub lands. A belt of subtropical deserts lies across both hemispheres. Deserts vary according to their locations, with some found along western coasts and some in the interiors of continents. Where climates are a little moister, subtropical deserts merge into savanna grassland. On either side of the equator there are tropical dry forests and rain forests. Mountain grasslands and shrub land biomes are not confined to particular latitudes.

The importance of biomes cannot be overestimated. Biomes have changed and moved many times during the history of life on Earth. More recently, human activities have drastically altered these communities. Thus, conservation and preservation of biomes should be a major concern to all.

~JM

Photo Credit: http://askabiologist.asu.edu/explore/biomes

More info:

World http://www.worldbiomes.com/ World Biomes Map – Colouring in: Awesome activity for kids. http://www.classroomsecrets.co.uk/world-biomes-map/ Blue Planet Biomes: http://www.blueplanetbiomes.org/world_biomes.htm Terrestrial Biomes: http://www.nature.com/scitable/knowledge/library/terrestrial-biomes-13236757

Central Asian steppe grasslands

The steppes of Central Asia stretch almost a third of the way around the world and include some of the least populated areas on Earth. In the west, the steppes reach the northern shores of the Black Sea, while they extend east in an irregular band almost to the mountains of China’s northeastern provinces on the pacific.

The immense grassland zone is bordered to the north by the Eurasian boreal forest and to the south by the Central Asian deserts. Dramatic swings in temperature are a defining feature of the steppes; on the grassy upland plateaus of Mongolia, it may reach 40°C (104°F) in summer and plunge to -20°C (-4°F) in winter. The annual rainfall of 200-600mm (8-23 ½ in) is sporadic, with prolonged droughts and sudden thunderstorms. Thick snow blankets the ground in winter. When the snow melts in spring, the steppes are briefly ablaze with a profusion of flowers including irises, hyacinths, crocuses, and tulips. During the short summer, feather and fescue grasses and sedges dominate the turf.

Apart from a few stunted trees confined to the sheltered valleys, the steppes are bereft of tall vegetation, although in northern China there is a more park-like landscape, with a scattering of trees such as elms. Animals of the steppes are adapted to the extreme climate in various ways. The Saiga Antelope has a bulbous, trunk-like nose that warms and moistens the cold, dry air it breathes, while rodents such as the Steppe Lemming, susliks, and gerbils dig burrows for shelter. Built like a heavy pony, Przewalski’s Horse is the only truly wild horse. At home on the steppes and in semi-deserts, it once ranged from the Urals to northern China. It was extinct in the wild by 1969, but more than 1,000 survived in zoos. Small herds bred in captivity are now being reintroduced to suitable sites.

~ JM

Image Credit: Mongolia Steppe. Labelled for reuse. http://bit.ly/1PvriWy. Accessed 16.06.16 More Info: Steppe Grasslands: http://bit.ly/1V5DgOf