Food Web DiagramThis print version free essay Food Web Diagram.
Autor: reviewessays 06 March 2011
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Food Web Diagram
The African Grasslands are areas where the vegetation is dominated by grasses and other herbaceous (non-woody) plants. Grasslands cover nearly 50 percent of the land surface of the continent of Africa. While grasslands in general support diverse wildlife, given the lack of hiding places for predators, the African Savannah regions support a much greater diversity in wildlife than do temperate grasslands. The root systems of perennial grasses and forbs form complex mats that hold the soil in place. Mites, insect larvae and earthworms inhabit deep soil, which can reach 20 feet underground in undisturbed grasslands on the richest soils of the world. These invertebrates, along with symbiotic fungi, extend the root systems, break apart hard soil, enrich it with urea and other natural fertilizers, trap minerals and water and promote growth. Some types of fungi make the plants more resistant to insect and microbial attacks.
Energy enters an ecosystem in the form of heat from the sun. This energy is absorbed by organisms such as plants, and is then converted to other forms of energy and stored. Once stored, energy is used for necessary life functions, such as growth, movement and reproduction. There are several kinds of organisms, such as bacteria, fungi, termites, grasses, trees, herbivores/omnivores, carnivores and scavengers, which can be found in the African Grasslands. The decomposers are living things (often fungi, insects or bacteria) that break down dead animals or plants and animal wastes to obtain energy and nutrients. The producers are plants (usually green) that take carbon dioxide and water and convert them to living matter using the energy of the sun. The consumers obtain its food by eating plants or by eating animals that have eaten plants.
There are four types of consumers within the African Grassland ecosystem. The herbivores (giraffes, zebras and impalas) are animals that feed mainly on plant material. The omnivores (baboons, jackals and civets) are animals that eat both plants and other animals. The carnivores (lions, hunting dogs, cheetahs and crocadiles) are meat eater. And the scavengers (vultures and hyenas) are animals which eat the remains of dead animals. A food chain, describe the feeding relationships between species to another within an ecosystem, shows how each living thing gets its food. For example, a simple food chain links the trees and shrubs, the giraffes (that eat trees & shrubs), and the lions (that eat the giraffes). Each link in this chain is food for the next link. A food chain always starts with plant life and ends with an animal.
The general structure of an ecosystem is more or less like a pyramid. Each level influences the number of individual in the other levels. Masses of plants (producers) are at the bottom and support the whole structure. If the plants that support the food chain are destroyed, the whole system will collapse. If an animal further up the chain is destroyed, that may cause a population explosion below and disrupt the balance of the ecosystem (ZAP, n.d.). Intense, short-duration trampling and dunging by grazing animals is a natural part of how ecosystems function in arid and seasonally dry environments. Removing grazers damages these ecosystems, which depend on disturbance by grazing animals to perform vital functions such as mulching soil and planting seeds. The intense trampling that mimics the effects of wild herds has proven effective at healing environmental damage in grasslands and deserts (Keppel, 2005). Overgrazing has reduced vegetation density and diversity, promoting soil erosion, decay, and loss of productivity. Pesticides can have an even greater impact because of their natural toxicity (obviously, the main purpose of pesticides is to kill pests). They may find their way not only into the leaves, fruit, and vegetative tissues of crops, but also into surface water bodies and groundwater. Some long-lasting pesticides may appear a few years after their application in the water supply of nearby towns or rural communities.