Thursday, December 1, 2011


Our ecosystem is the African savannah.  This is a fascinating, and extremely important ecosystem to the plants, animals, and peoples inhabiting Africa.

XOXO Tulsi & Hayley

Location and Classification

On a general scale, the African savannah forms a semicircle around the western central rainforest areas of Africa and is bordered by desert areas to the north and south.  Some major locations of African savanna on the continent are Nigeria, Uganda, Kenya, Congo, Orinoco River, Niger River

Present day Savannah regions in Africa

The African savannah ecosystem is composed of a number of different micro-savannah environments, which fall into a variety of classifications ranging from broadleaved savannas to woodland savannahs. 
Broadleaved savannas are found in the subhumid interior plateau region.  These savannahs are typically found on old, infertile soils that tend to be highly-weathered.
Fineleaved savannahs exist in semi-arid, low-lying regions, bordering the broadleaved savannah regions.  Fineleaved savannahs are nutrient-rich.
Sudan-type savannahs are found in northern Africa.  The grasses in these savannahs are xerophytic, meaning that they have adapted to an environment that lacks water.  Scattered with deciduous trees, Sudan-type savannahs form a transition with Saharan desert vegetation.
Guinea-type savannahs are savannah woodlands.  These are found primarily in eastern Africa and form a transition with evergreen moist forests.  Dominated by herbaceous plants, Guinea-type savannahs are also characterized by scattered trees and shrubs.
The final classification of African savannah is the “Miombo” woodland savannah, which occurs in southern Africa.  This micro-savannah environment is dotted by a number of distinctive tree species, including the Miombo trees, which fall into the Brachystegia genus.  These trees are endemic to the Miombo woodland savannah.

The various different types of savannah that coexist to make up the extremely diverse African savannah

Historical Characteristcs

The African savannah landscape arose where climate was too dry and too cold to support a rainforest environment; thus, one may say the area of the savannah increased at the cost of a rainforest.  After evolving over a period of several million years, finally, sometime after the middle of the Miocene period, the proportion of savannah grew equivalent to what we know it as today.  Along with the evolution of the savannah came other important environmental changes that impacted its look and composition.  Between Miocene and Pliocene periods, there was a decrease in atmospheric threshold for carbon dioxide, which caused a change of vegetation from C3 to C4 plants (grasses); thus leading to the expansion of the savannah.
This shows how the Savannah spread throughout Africa over millions over years, the numbers below the continent are in millions

Present Characteristics

Today, the African savannah is an ecosystem with dense patches of tree groves and spread-out woodlands and copses.  The majority of the vegetation is comprised of grasses interspersed sporadically with Acacia trees.  These trees, like the vast majority of savannah plants have adapted to the predators and environmental factors present in this ecosystem. For example, Acacia trees bear thorns to protect against hungry herbivores; while other trees, bushes, and grasses have adapted to fires that annually occur in the savannah. In other areas of the African savannah, there grows dense gallery forests along permanent water sources; because of constant water availability, the vegetation remains lush year round.  Today, the African savannah supports a wide variety of mammals and birds including hippos, zebras, wildebeests, giraffes, gazelles, cheetahs, and elephants, each perform important ecological roles that help maintain the landscape characteristics of the African savannah

A lioness and her adorable cubs lounging in their natural habitat

Current Human Impacts: The Good, The Bad, The UGLY!

Overall, humans’ impacts on the African savannah have been negative.  While humans’ influence has had a few positive consequences, the cons certainly outweigh the pros in the case of this ecosystem.

The Good:
Tourism keeps natural sections of Africa alive.  The money brought in by tourism helps fund conservation reserves and shows the government and local communities that conservation of animals and the landscape is important because millions of people travel thousands of miles to come to Africa to observe and explore these landscapes. 

The Bad: 
For one, humans have overused fossil fuels, and this over consumption of fossil fuels has led to increased levels of carbon dioxide rising to the atmosphere.  The result has been a shift in vegetation from C4 plants to C3 plants.  This is bad because most animal species have evolved with C4 plants.  The shift away from C4 plants has the potential to disrupt the food chain and ecological balance of the ecosystem since smaller organisms and herbivores lower down on the food chain depend on C4 plants for food and shelter, and lack of C4 plants would thus compromise the survival of these organisms and in turn, the survival of omnivores and carnivores higher up on the food chain that eat these plant-eating creatures.  In sum, the shift from C4 to C3 plants has the potential to severely disrupt and dramatically damage the balance of this ecosystem.

The Neutral:
If humans want to transform the land for pleasure purposes, all they need to do is simply turn it into a park; this allows no destruction of the land to be done.

Another increasingly common problem for the African savannah is agriculture.  Social and economic influences from humans have forced savannahs to be converted into agricultural lands and fields as humans increasingly urbanize wild landscapes.  On top of the loss of rangeland and habitat for animals of the African savannah, increased use of fertilizer and irrigation pollutes the land surrounding agricultural spaces.  At the same time, monoculture cropping (the planting of just one type of crop) severely depletes the soil of nutrients, leading to environmental degradation that changes the makeup of the African savannah.
Furthermore, the introduction of grazing livestock to the savannah lands has led to overgrazing and overcrowding of watering holes; thus depleting the landscape of both vegetation and water.  In fact, livestock is one of the biggest threats to the African savannah because if just three families try to live on the same plot of land, it can immediately become overgrazed.
In addition, humans have further damaged the ecosystem by hunting many species of animals to the brink of extinction or critical endangerment.  Many megafauna have already gone extinct, and many more continue to be poached illegally and in high numbers.  A prime example is illustrated by “The Elephant Problem,” which was when elephant poaching for ivory was so rampant in the 1970’s and 80’s that 2/3 of the African elephant population was killed.  In addition to megafauna, other smaller animals have also been hunted mercilessly.  Most notably, poor Africans in rural villages and destitute towns kill animals for meat – particularly bush meat – and fur, to sell the profits for income.  In this way, humans have removed many native animals from their surroundings.  Extracting key native animals species ruins the ecological balance of the ecosystem.  Thus, when animals that once play an important role in maintaining the ecosystem disappear, if no other animals fill their niches and perform exactly the same or very similar ecological roles, parts of the African savannah begin to change into a different ecosystem, which negatively impacts the remaining animals and floral composition.

 While fires are essential to maintaining natural landscape of the African savannah by removing dead and decaying organic material and thus rebalancing the ecosystem environment, humans increasingly prevent fires to protect pasture and farm lands.  Fire prevention in the African savannah subsequently threatens the ecosystem because without fires, bushes encroach on landscape, changing the makeup of the savannah and turning it into a long-term forested area.  Meanwhile, sans fire, organic matter and litter accumulate to such an extent that when fires do set in, they end up being massive and destructive to the landscape and environment on a large scale.                                   
However, overburning by humans to reduce bush encroachment and natural re-recruitment of trees leads the ecosystem to be more vulnerable to invasion by foreign species, which further transforms and upsets the balance of the land.

 Keep the Savannah beautiful! Save the Elephants!

Future Prospects

Based on the current human impacts, it seems that the future prospects for the African savannah are not looking up as of now because of increased encroachment on savannah lands due to agriculture, livestock grazing, urbanization, carbon emissions, and control and manipulation of fire.  As a consequence of these problems, lands that have already been touched or affected by anthropogenic activity are too far changed or destroyed to save.  Additionally, as the human population in Africa continues to grow, mankind’s gaze turns further towards settling parts of the African savannah, thus turning these lands over to human exploitation and ruin. However, due to National Parks, the future of the Savannah seems promising, as long as untouched areas of the African savannah may continue to be exactly that: untouched.  If local and national authorities can strictly and conscientiously implement conservation efforts such as large, protected reserves, as well as laws aimed against trespassing through protected lands and illegal poaching, these as-of-yet untouched areas may have some hope of retaining their natural features, flora, and fauna, keeping the African savannah a pure ecosystem, at least in some parts of Africa

Improving and Protecting the Savannah:

      Humans have established certain protected areas for maintaining the richness and diversity of the African savannah.  Namely, national and peace parks have been established in several parts of Africa, especially South Africa.  These are maintained by South African National Parks organization, which also manages Murchison Falls National Park and Serengeti National Park.  The goal has been to protect the flora and fauna of the landscape.  As well, Free State and Eastern Cape are provinces in South Africa that are heavily protected to protect the existing savannah landscape from poaching, burning, encroachment, and destruction.  The European Union is greatly contributing to the conservation efforts to restore habitats and biodiversity throughout the savannah lands in Africa.  Somewhat ironically, although tsetse flies carry and spread fatal parasites to both humans and their livestock, they are saviors for the African savannah as large groups of tsetses keep areas of this ecosystem untouched by humans.  These measures are great strategies for improving the condition of the landscape in areas where it has been damaged.  And, in areas that are fully or at least somewhat untouched by anthropogenic influence or activity, such establishments of national parks and protected areas will help to keep the species richness alive, as well as the proper balance of the ecosystem.  This will better both the ecosystem, as well as improve the condition of surrounding ecosystems and environmental conditions which get affected by changes to the African savannah.
    Another way in which the African savannah can be improved and preserved is by humans continuing their global tourism activities.  When thousands, even millions, of people come from around the world to see a magnificent, electrifying display of thousands of unique species of plants and animals dotting the yellow and green expanse, they bring in tons of money for the funding of conservation programs in the country they are visiting and also show the government and local authorities how important it is to conserve and preserve the environment of this ecosystem so that it can continue to be viewed as a beautiful, intriguing, rich, and diverse landscape and continue bringing in tourists, which in turn continues to enhance that country’s economy.
    As well, humans must be convinced to stop buying products made from skins of wild, endangered animals.  Furthermore, mankind must develop new sustainable methods and renewable sources for necessary resources, such as using elephant poop to make paper, rather than chopping down the remaining scattered trees on the savannah landscape. 
In addition to the above-mentioned strategies, an important way to maintain and improve the African savannah ecosystem is to keep indigenous peoples on the lands, since the animals and indigenous peoples evolved together on the African continent.  Because of the conjoined evolution of these groups, the indigenous peoples know how to care for the land and use its resources sustainably.  By learning from them and understanding their ways, as well as educating them about the effects of their living styles, people looking to settle or work the land can learn more sustainable methods that have less environmental impact on the land and its species.
    In sum, considering the best strategies towards improving and maintaining, conserving and preserving, one finds that all strategies start with education.  The local farmers clearing lands for agriculture, the hunters poaching elephants, rhinos, etc., the rural folk killing bush meat, and urban developers must be educated about the consequences of their actions for them to consider what course of action they must take to improve the condition of the environment which they have had a hand in damaging.