(i) Resource degradation: Continually increasing population Africa I already
exerting enormous pressure on the available resources making their
sustainable use almost impossible. Some of the affected resources include:
(ii) Agricultural land: Increasing populations have forced people abandon their
traditional farming systems that involved leaving land on fallow land as
shifting cultivation. Instead land is cultivated year in year out without a rest
and usually without the use of manure and /or fertilizers. Infertile soils are
known to be quite vulnerable to erosion and soil erosion has been reported in
many areas where agriculture is practiced. Soil erosion results in nutrients loss
and consequently a drop in crop yields. Increasing cases and levels of poverty
have aggravated the problem of soil infertility, as many farmers are unable to
use farm inputs to intensify their farm operation. Reduced soil fertility and
land degradation in general have compounded the food insecurity problem in
the region.
Silt transported down stream clogs irrigations channels and dams. For
example the Masinga dam which is the main source of Hydro-electric power
in Kenya is silting at an alarming rate due to poor land use in the upper Tana
River catchments. Continued siltation in the dam will have devastating costly
effect in the country. The situation is the same in most African countries. In
some cases excess populations migrate to marginal lands introducing
improper farming method in the already unstable and fragile ecosystems,
hence land degradation followed by desertification.
(iii) Forests: More people than ever before are encroaching into forested area in
search of land for settlement and cultivation as well as forestry products. For
instance, the Sabaoti of Uganda and Kenyan in the Kenya-uganda frontier
have encroached on Mt Elgon clearing forests at a worrying rate. Generally,
forest destruction has had devastating effects in Africa. It has resulted in:
- Loss of biodiversity: Forests are home to fauna and flora. There are
countless birds, insects and mammals, which live and feed in forests and a
variety of tree species. A typical patch of 10km2
of rainforests eg in Kakamega forest in Western Kenya, may contain as many as 1,500 species
of flowering plants, 750 species of tree, 400 species of birds, 150 varieties
of butterflies, 100 different reptiles and 60 types of amphibians. When
such a patch is destroyed, all the fauna and flora is as well destroyed as
they are left homeless. Destruction of foresters and other animal habitats
has resulted in serious human-wildlife conflicts. In their efforts to survive,
animals encroach on human property leading to loss of life and property.
Numerous cases of elephants and buffaloes etc. destroying crops, killing
and or maiming people in the Mt. Kenya area have been reported.
- Loss of nutrients: Deforestation reduces the amount of leave fall in the
affected areas. Leave fall is a great source of humus in the soil. A
reduction in leave fall means less humus in the soil , a problem aggravated by high levels of leaching in the tropics. Soil with a low
organic content (humus) cannot support a luxuriant tree cover and
consequently the quantity and quality of trees in the forested areas is
drastically reduced.
- Accelerated soil erosion: tree canopy protects sols from heavy rains; roots
bind the soil together while level fall augment organic content of the soil.
Without the protective tree cover, there will be less interception and
infiltration, and as such surface runoff and soil erosion will increase.
Siltation increases the extent and frequency of flooding, reduces
agricultural productivity, and increases siltation of irrigation channels and
dams.
- Increases carbon dioxide: We know trees use carbon dioxide (CO2) in the
photosynthesis process and are actually referred to as carbon sinks.
Cutting trees therefore increases CO2 in the atmosphere aggravating the
problem of global warming. On the other hand, trees are a good source f
oxygen. For instance, recent investigations have suggested that over one
third of the worlds oxygen supply come from trees in the rainforest and
that a quarter of the world’s water is stored in the Amazon forest.
- Harsh micro and macroclimate: Forests have a significant influence on
micro and macroclimate. Trees, though the process of transpiration,
transfer tones of water from the soil to the atmosphere. Under favorable
conditions this water can lead to the formation of rainfall. In addition,
close growing trees in a forest produce microclimates beneath their dense
leaf-cover often having a reduced temperature range and relatively higher
humidity. Thus destroying forests generates harsh micro and
macroclimatic conditions, which reduced the productivity of the affected
ecosystems
- Shortage of fuel wood and timber: Forest are exploited for domestic and
commercial purposes. There is an increasing demand for trees for timber
for building, fuel wood, paper industry etc. For instance fuel wood is the
main source of energy in rural East Africa. Over 80% of rural folks use
firewood and charcoal for cooking. Another significant number of urban
population use charcoal for cooking. Unless the high rate of deforestation
is reversed, East Africa may be unable to meet the increasing demand for
fuel wood and timber.
- Water degradation: Water degrading is evident where population growth
causes higher demand than the supply. On one hand, water quantity
declines following an increase in its demand to meet domestic, agricultural
and commercial needs. On the other hand, water quality declines too, as a
result of agricultural and industrial related pollution. As the demand for
water increases, conflicts arise a people fight over the available water. For
instance in January-February 2005 water shortage sparked ethnic clashes
mainly between the Maasai and Kikuyu in Mai-Mahiu Naivasha, Kenya
where over 10 people were killed.
(iv) Glutted labour market: A high rate of population growth results in an increase in
the number of people joining the labour force. This is a serious problem in East
Africa where generation of employment opportunities is remarkably low and sow
compared to the number of job seekers; a problem attributed to East Africa’s low
economic growth. Between 1980 and 2000 for instance, Kenya Uganda and
Tanzania realized an economic growth rate of about 0.0%, 5.1% and 4.0%
respectively (http://www.nationmaster.com).Consequently, the rate of
unemployment has risen in ordinary to a situation whereby the labour market is
glutted. For example the rate of unemployment is over 40% in the three East
Africa countries.
(iv) Inadequate social and economic infrastructure: A rapidly expanding population
exerts increasing pressure on the social and economic infrastructure of the
concerned countries. Schools, hospital and other facilities become inadequate
almost as soon as they are constructed. Urban zones like Cape Town, Cairo Addis
Ababa, Lagos etc, are experiencing an acute house shortage problem. The
ongoing rural to urban migration has aggravated the housing problem further.
Consequently slums and ghettos have developed in the big cities.
Titany answered the question on January 17, 2022 at 13:56