Temperate+Grasslands

=Temperate Grasslands = =Geographic Location:= ====Temperate grasslands are generally found in the mid lattitudes, and in the interior of continents. They are typically too dry for trees to grow, and fires frequent these areas becuase of this. The grasses perpetuate primarily because of these fires. Due mostly to their extensive root====

systems, the grasses are able to regrow very quickly. Trees would be unable to recover from such frequent disturbances, so survival of the fittest favors grasses.
=Abiotic Conditions:= ====These areas are dry, receiving only 10-20 inches of rain per year, and frequented by fires, and are generally characterized by an extremely flat landscape. The "wind comes sweeping down the plain..." frequently in this area, and this contributes to the severity of natural fires. In these areas, it can get very cold in the winter, and very hot in the summer due in part to the lack of a large body of water for temperature moderation, and due in large part to latitude.====

=**Native Species:**= ====Most grasslands support such native animals as buffaloes and bisons, deer species, kangaroos (in Australia), rodents, pumas and jaguars (in South America), cheetahs and leopards (in Africa), wolves**,** foxes, snakes, moths and butterflies, thistles, and weeds.====

=**Nonnative Species:**= ====In some grasslands (particularly Australia), such nonnative species as camels, donkeys, sheep, horses, and (worst of all) rabbits, all of which overgrazes the grassland and accelerates erosion, have been introduced. In addition to animals, plant species such as teasels, reeds, and spurges are also considered to be invasive due to their capabilities to reproduce quickly to crowd out native species.====

=Indicator Species:= ====The American Bison follows the melting snow north, indicating that it always searches for the healthiest grasses; assuming no hunting, a decline in migration would mean that the area of grassland is shrinking. The population of Przewalski's horse, once ubiquitous in the steppes of Asia, was in sharp decline during the past decades due to hunting, indicating the increase in hunting activities around Mongolia and Central Asia.====

=**Keystone Species:**= ====In African grasslands, the elephant helps maintain the milieu. Too often in grasslands, certain tree species (particularly acacias) sprout among the grass -- and if the trees grow unchecked, they can block sunlight for the grass and allow trees to dominate the landscape; the disappearance of grass, in turn, forces antelopes to migrate. African elephants, however, help eliminate the growth of trees by yanking the sprouts out by their roots before trees can grow.====

=**How Species Avoid Interspecific Competition:**= ====Large herbivores often compete for grass in grasslands; as a result, many of them tend to remove certain species of grass at the expense of others**.** This forces other species to move to other areas in order to find the particular grass, thus avoiding competition between two species of herbivores.==== =**Predator-Prey Relationship:**= ====The lion is a predator in the African grasslands that preys on antelopes, among other animals. To do so, lions often hunt in teams, and they would pursue the prey while it is not looking (likewise, the lions would freeze and hide themselves within the grass to avoid detection). When the lion pride is within striking distance, the group would ambush the prey, killing it. Such moves can help regulate antelope populations in grasslands, which would in turn help reduce overgrazing.==== =**Symbiotic Relationship:**= ====An example of parasitism is the interaction between roundworms and sheep; eggs are laid within open pastures (where sheep usually graze), which are then eaten by sheep, ultimately harming the sheep. A mite on a beetle indicates commensalism in a grassland; the mite effectively "hitchhikes" on the beetle, while nothing happens to the beetle. Mutualism in grasslands can occur within roots of plants; for example, certain bacteria species perform nitrogen fixation in exchange for energy-rich carbohydrates provided by legume plants.====

=Grasslands Up For Grabs?= ====Since we have come into contact with them, we have destroyed nearly half of all grasslands to date. 41% has been converted to farmland, and 13.5% has been sacrificed to industrial development/degredation. In this market economy, we only show the value of a biome by its dollar value if converted to industrial wasteland, suberbia, or farmland. This cannot be accepted because the intrinsic value of undisturbed grasslands is almost never taken into account. These pastoral areas must be taken care of, and the "development" of the mid-west must be postponed if the sustainability of this great natural resource is to be maintained.====

[]
=Citations:= [] [] [] [] [] [] [] [] []