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Buy an essay: 2. Biodiversity and the survival and expansion of local communities over time

On analysing development and history of Africa, such notion as biodiversity traditionally plays a very important role. In fact Africa is well known for its rich flora and fauna and many specialists underlined that such richness is one of the key factors contributing to biodiversity existing in the continent. However, Jams McCann in his works go beyond the traditional definition of this notion. According to him biodiversity should include not only the abundance of flora and fauna that exist in nature but he also underlines the importance of human activity in the continent and consequently he believes that the results of human activity should also be taken into consideration. To put it more precisely, he reminds that agriculture developed by people in Africa, as well as in any other continent, can also contribute to biodiversity, resulting in certain changes in local landscapes and natural conditions.
It is not a secret that human activity in certain areas can change the situation radically, as it happened in the case described above in Ghana, i.e. the agriculture developed by local population changed dramatically the forest landscape and increased biodiversity without rapid deforestation. In such a way important fact that he underlines is the role of human activity as one of the factors contributing to increase of biodiversity through a number of factors such as soil fertility, irrigation, new crops, socio-economic factors, including the situation in the local and international markets, which stimulate cultivation of certain plants, for instance, implementation of new technologies that eventually lead to better survival and expansion of local communities over time and increase of biodiversity.buy an essay
In order to better understand the role of human activity and biodiversity in James McCann’s interpretation, it is necessary to briefly dwell upon some historical examples. For instance, on analysing the environmental changes along the Western Sahel since 1000 till 1850, he underlines that there were two distinguishing historical periods from 1000 to 1630 and from 1600 to 1850. He delimits two key West African historical zones not by fixed geographical boundaries but by shifting rainfall boundaries (so-called isohyets) that generate particular types of vegetation and humidity impose specific constraints on human activity. The 100 mm rainfall zone separates the Sahara from the Sahel while the 400 mm line demarcates the Sahel’s southern edge and the zone where cultivation of drought-tolerant crops like sorghum and millet is possible. South of the 400 mm line is the savanna itself, which is described by the author as a bright country where Sundiata and his royal Keita clan founded the Mali empire in the middle of the thirteenth century.
Furthermore, James McCann underlines that food supplies in their type and reliability also reflect moisture. For instance, sorghum and millet, being West Africa’s historical crops, are drought-resistant but long maturing and offer relatively low yields per unit of lands. In contrast maize, which arrived after 1500, offered much higher yields, even double cropping in some areas. It also offered earlier maturity than traditional African crops and was ready to harvest and consume a few months earlier. However, maize flourished in humid and semi-humid zones but quickly disappeared in many areas in the nineteenth century when annual rainfall fell below 400-500 mm.
In such a way, this example reveals two distinct periods when at first traditional Africa’s crops such as sorghum and millet prevailed then they were later substituted by maize that also eventually disappeared but all these changes affected dramatically the local environment leading to its gradual degradation.