Savannas are part of the Grassland biome, and are generally found in regions dominated by the Wet-Dry Climate. Tropical Savannas encompass almost one half of the entire continent of Africa as well as many parts of Australia, India, Mexico, and South America. The Tropical Savannas in Australia take up over one-third of the country, and provide natural resources that contribute much of the money that supports the national economy.
The Climate is the most important factor in creating a savanna. Tropical Savannas are always found in hot weather with a mean temperature of among eighty-five to ninety degrees Fahrenheit, where the annual rainfall is from about twenty to fifty inches per year.
Yet the rain does not fall at a constant rate all year. In fact, practically all the rainfall is condensed into six months of the year, known as the Wet Season. On the contrast, the following six months is a long period of drought, and yes, this time is called nothing but the Dry Season.
Savannas, are often what surrounds the very wet Tropical Rain forest.
The Abiotic factors, non-biological factors that are part of Savannas are temperature, climate, soil, and sunlight. All of these factors are crucial to the biome and how it the organisms in it succeed. Most Savanna soils are rather poor, but they have better quality of soil than that of the soil in the rainforest. But the savanna has less rainfall, and plants need water to survive.
Biotic factors, or biological factors that influence and are a part of this biome are ALL organisms living in the biome.
The vegetation of the Savannas consists of tall grasses such as star grass, and red oat grass both of which can grow reaching a height of three meters. Trees are present but not amply because since the water is so scarce, trees are unable to grow profusely and are subjected to grow in only the places wherever tree roots can reach underground water. A few notable species of trees in the savanna are Acacia tree and the baobab tree. Plants in the savanna have to adapt to the long dry season in a number of ways. The Baobab tree stores water in its trunk , drawing on the moisture and then go into a state of dormancy. Grasses turn brown and trees turn their leaves to reduce transpiration. Transpiration is the loss of water by evaporation through pores in the shoot system of the plant. These plants need to adapt because if they dont then their species would eventually become extinct.
In every biome the Abiotic and biotic factors interact with one another. The sunlight helps with the photosynthesis of the trees and the vegetation who then take in the carbon dioxide in the air, and produce oxygen for the animals and other oxygen in taking organisms. The soil is also a breeding ground and living shelter for many small creatures. These creatures such as the earthworm and African termite and beetle need the soil to shield and conceal them.
Energy, the capacity to do work and transfer heat is necessary to obtain, in order to survive in any environment. Energy comes in many forms. The sun is the main origin of energy. It provides the nutrients needed for plant growth or the producers, which provides food for the primary consumers, the herbivores. The carnivores being the secondary consumers feed on the primary consumers. This way of classification is known as Trophic levels.
The data shown in the table below shows the Predator-Prey relationship of the Thomson Gazelle and the Cheetah located in the tropical savanna region of East Africa.
The table shows that even despite of the fluctuations in the population of both the cheetah and the thomson gazelle, they remain constant. This table is shown in the graph below. When looking at the graph, it clearly shows that at times, both species appear to be going towards extinction. But, in the end of the eleven year period, both animals seem to be increasing rapidly again.
The main threat to the tropical Savanna is the increasing of the human population. Humans have outgrown their habitat so they are now taking over others. With this, they are also introducing new non-native domestic cattle into the savannas and these animals are destroying the grasslands. This in turn reduces the amount of available food for the native wildlife. The reduction of these grasslands are causing many of the grazing animals to come closer and closer to extinction. Humans not only bring onto the land new cattle to aide in the native animals extinct, but it is also helping it in a different way. Poaching has always been a problem throughout Africa .
Many animals like the rhinoceros are endangered and threatened with extinction due to hunting and habitat loss. The African Elephant, is in danger of extinction due to poaching for its ivory tusks. The natural wildlife conservation fund have gone through several means to protect these animals have been tried, and has gone the great lengths in order to preserve these animals. They have even tried the removal of the rhinoceros horns and the Elephants tusks . Humans aren't the only threat though. A Problem known as desertification is also becoming a large problem. Overgrazing of our grazing animals, i.e. zebras and wildebeest, has reduced the capacity of the the biomes system, to withstand to erosive forces of wind and water. With this, it is easy for plants, soil, sand, and valuable nutrients in the soil, to blow away from the surface. Deserts are rapidly replacing savannas. Due to the dry season where savannas have very little water it is common to have prolonged drought; drought and humans cutting down trees increases the likelihood for desertification.
Possible ways in order to solve desertification is creating dams to controls erosion, reforestation to the areas with barren fields, planting windbreaks. These measures can not all be done though. They are all very expensive for countries with limited resources. The organism we designed to be ideal for the tropical savanna is known commonly as Chachezelle. This animals is has the main characteristics of the cheetah, the grant gazelle, and has chameleon like tendencies. It is as swift as the cheetah, but with hind legs similar to the grant gazelle.This animal can change its color according to its surroundings. This camouflage helps the animal to cleverly sneak up upon the prey inorder to attack. Yet when the going gets tough and the carnivorous food becomes scarce, it can easily consume grasses and other primary producers.
An omnivore is definitely ideal for the tropical savanna. With the Chachezelle now in the savanna, it may disrupt how the ecosystem now coexists. It would make the balance between the grazing animals and the carnivorous animals. How energy gets distributed is most essential to life in the savanna. The primary producers, i.e. Acacia trees, red oat grasses, and baobab trees have the most energy than any other organism living in the savanna. They are autotrophs and get their energy primarily from the sun. These autotrophs or primary producers are then consumed by the primary consumers. The primary consumers, i.e zebras, gazelles, wildebeest, get ten percent of energy from what the producers have. From there, the secondary consumers come into play, these animals such as cheetah, lion, and hyena consume the primary consumers and then receive ten percent of the energy from them.
Once the animals die their energy get stored in the soil and used again in the cycle. For example: the red oat grass is consumed by the Thomson gazelle, the Thomson gazelle is then attacked and consumed by the cheetah, the cheetah is consumed by the lion, the lion once dead is consumed by the vultures and the land scavengers, and they are consumed by the decomposers. Symbiotic, mutualistic, and parasitic relationships are very common in the savanna.An example of a symbiotic relationship is the African Elephant and the tick. The tick lives on the elephant and shields them. The elephant receives benefit as well. They get cleaned and maintain that any outside parasites do not come in to the elephant and damage. A type of parasitic relationship is the African termite and the Acacia trees. The termites consume all the nutrients from the inside of the tree killing it.