African Savannah Ecosystem and Its Threats

This article discusses the African Savannah ecosystem, its characteristics, and the threats it faces due to human activities. It covers topics such as wildlife, trees and vegetation, and building of roads. The article also highlights the need for conservation of the savannah ecosystem.

Running head: SAVANA ECOSYSTEM
Savana Ecosystem
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Introduction- like the several other biomes in the world, the same way the savannah
grasslands also sustain through a balance between the various species, humans and
environmental factors. Drought can severely jeopardise the sustainability of the grasslands, while
the indigenous people and poachers which threaten to misbalance the food web by killing the
animals for survival and sports (Perrings and Halkos 2015). The usage of the savannah biome by
humans is increasing and it has led to the increase in imbalances in nutrient availability, water
balance, nutrient loses, no cultivation of the cash crops with overemphasis on the subsistence
cultivation, degradation of the soil resources and vegetation resources. in addition to the wood
production, fibre and food, the savannahs are also used for urban developments, tourism
developments, national parks and mining (Osborne et al. 2018). This study will be based on the
description of the African savannah ecosystem and the current threats faced by these systems.
African Savannah ecosystem- the African Savannah can be described as a tropical
grassland and it includes is located between the latitudes of 15o N and 30o S and longitude 15o W
and 40o W. The annual rainfall in Savannah grasslands is similar to the rainfall in Wisconsin.
During the months of rainy the rainfall gets to about 15 to 25 inches in a single month. The span
of the dry season is seven months a year. The wet season has a high sun period and the dry
season has a low sun period (Ogutu et al. 2012). Savannah has a combination of wet-dry climate.
The African Savannah can be characterized by dispersed or small trees, grasses and the trees do
not form closed canopy and it provides ample space for the sunlight to reach the ground. The
African Savannah has a community of diverse organisms and they interact to form a complex
food web. The Ngorongoro and Serengeti are the two major conservation areas which has also
been marked as a World Heritage Site. The half of the African continent is savannah and it takes
up about 5 million square miles (Hoffmann et al. 2012).
Threats faced by the African Savannah ecosystem- Beale et al. (2013), highlighted the
need for the conservation of the savannah ecosystem and ten major issues were found through
workshops. The ten major problems or the issues identified are the inadequate science and
practitioner interaction; allowing the loss of the functional heterogeneity; inappropriate planning
of the roads; late response to the invasive species; insufficient law enforcement; insufficient
protection of the river catchments; degradation of the migratory corridors; lack of the buffer
zones; inferior quality of the public relations, wrong boundaries.

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Wildlife- It has been highlighted by Waldram, Bond and Stock (2008), that herbivores
can change the spatial heterogeneity and the structure of a vegetation. An experiment was carried
out the authors on the effect of white Rhino on the grass sward. It has been found that the white
Rhinos were capable of maintaining the patches of short grass and when the white Rhinos were
removed, the height of the sward grass increased. Also, it is seen when the white rhinos were
removed, the other grazing communities were unable to maintain the short grass communities.
While in the semi-arid regions, the small grazers are being able to maintain the height of the
communities of short grasses. The vital part is that the removal of the white Rhino increased the
rates of fire by indirectly increasing he fuel continuity and fuel load. Thus, according to the
authors White Rhino in the Savannah ecosystem is ecosystem engineer in both maintaining and
creating short grass swards. The Savannah ecosystem is an amalgamation of the different type of
the flora and fauna. According to Bennett (2015), there are several types of the poaching
activities of the African wild animals and specially they are done for trade of animal parts. One
such poaching activity is the illegal hunting of the African elephants for the trade of ivory and
this is causing major decline in the population of the African elephants. Since the year 2007, the
ivory trade doubled and it has led to the crisis in the conservation of the African elephants.
However, one solution to end this problem was put forward and it was to legalise and control the
trade of the ivory. The implementation of this solution has not been fructified due to the corrupt
officials operating in the area. It is important to highlight that the poaching related threats are
also faced by animals like saiga, tigers, pangolins, Asiatic black bears, freshwater turtles and
tortoise.
Trees and vegetation- According to Bond (2008), the plenty of the areas in savannahs are
under the climate types that support forests. There are several factors that contribute to be
detrimental for the formation of vegetation and it includes the soil, fire and climate. It is
important to highlight that the grass population differs from the woody ecosystems in terms of
the regeneration niche. The grasses are unable to grow within the tree population due to the
varying degrees of competition, herbivores, and fire. In several grasslands the population of the
tress are increasing and it has led to the shifting in the grass-forest boundaries. This has affected
the functioning of the ecosystem and it has cascading effects on the ecosystem. In order to
analyse the changes in the C4 grass biomes, it is necessary to integrate the aspects like the
demography, herbivore ecology, fire, ecosystem physiology. It has been highlighted by Sankaran

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et al. (2005), disturbance regimes like herbivore, fire and availability of the resources like
nutrients and water plays a major role in the regulation of the woody cover in the savannah
ecosystems. Authors have mentioned that the across the African Savannah, approximately 854
sites receives a rainfall of less than 650 mm. This plays a role in controlling the coexistence of
the grass and woody cover. Smit et al. (2010), has mentioned that the fire plays a role in shaping
the savannahs. Both the fire season and the fire frequency plays a cascading effect on the
biodiversity. According to Wigley, Bond and Hoffman (2010), the woody plants move into the
grassy biomes and this is contributed by the factors like the atmospheric carbon dioxide, fire
suppression, heavy grazing and changes in the land use. Studies by the author have indicated that
tree cover has increased in the areas like commercial sites, communal sites and the conservation
sites and this is contributed majorly by the land use practices.
Building of roads- Dobson et al. (2010), has mentioned that building of roads within the
Serengeti National Park will ruin the ecosystem and it will hamper the environment within the
National park. The construction of the roads will act to disrupt the environment and will hinder
the migration of the wildebeest. Studies have shown that the construction of the roads will plays
a major role in reducing the population of the migrator species and it will result into the collapse
of the Serengeti national park. The region from being sink of carbon dioxide will turn into a
source of carbon dioxide.
Conclusion- from the above discussion it can be concluded that the African Savannah
can be characterized by dispersed or small trees, grasses and the trees do not form closed canopy
and it provides ample space for the sunlight to reach the ground. The African Savannah has a
community of diverse organisms and they interact to form a complex food web. The usage of the
savannah biome by humans is increasing and it has led to the increase in imbalances in nutrient
availability, water balance, nutrient loses, no cultivation of the cash crops with overemphasis on
the subsistence cultivation, degradation of the soil resources and vegetation resources. in addition
to the wood production, fibre and food, the savannahs are also used for urban developments,
tourism developments, national parks and mining.

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