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FOOD SHORTAGE CAUSES, EFFECTS AND SOLUTIONS
Food shortage is a serious problem facing the world and is prevalent in sub-Saharan Africa. The scarcity of food is caused by economic, environmental and social factors such as crop failure, overpopulation and poor government policies are the main cause of food scarcity in most countries. Environmental factors determine the kind of crops to be produced in a given place, economic factors determine the buying and production capacity and socio-political factors determine distribution of food to the masses. Food shortage has far reaching long and short term negative impacts which include starvation, malnutrition, increased mortality and political unrest1. There is need to collectively address the issue of food insecurity using both emergency and long term measures.
Causes of food shortages
There are a number of social factors causing food shortages. The rate of population increase is higher than increase in food production. The world is consuming more than it is producing, leading to decline in food stock and storage level and increased food prices due to soaring2 demand. Increased population has led to clearing of agricultural land for human settlement reducing agricultural production (Kamdor, 2007). Overcrowding of population in a given place results in urbanization of previously rich agricultural fields. Destruction of forests for human settlement, particularly tropical rain forest has led to climatic changes, such as prolonged droughts and desertification. Population increase means more pollution as people use more fuel in cars, industry, domestic cooking. The resultant effect is increased air and water pollution which affect the climate and food production.
Environmental factors have greatly contributed to food shortage. Climatic change has reduced agricultural production. The change in climate is majorly caused by human activities and to some small extent natural activities. Increased combustion of fossil fuels due to increasing population through power plant, motor transport and mining of coal and oil emits green house gases which have continued to affect world climate. Deforestation of tropical forest due to human pressure has changed climatic patterns and rainfall seasons, and led to desertification which cannot support a crop production. Land degradation due to increased human activities has impacted negatively on agricultural production (Kamdor, 2007). Natural disasters such as floods, tropical storms and prolonged droughts are on the increase and have devastating impacts on food security particularly in developing countries. There are several economic factors that contribute to food shortage. Economic factors affect the ability of farmers to engage in agricultural production. Poverty situation in developing nations have reduced their capacity to produce food, as most farmers cannot afford seed and fertilizers. They use poor farming methods that cannot yield3 enough, even substantial use. Investments in agricultural research and developing are very low in developing nations. Recent global financial crisis have led to increase in food prices and reduced investments in agriculture by individuals and governments in developed nations resulting in reduced food production.
Effects of food shortage
There are a number of short term effects of food shortage. The impact on children, mothers and elderly are very evident as seen in malnutrition and hunger related deaths. Children succumb to hunger within short period as they cannot stand long period of starvation and they die even before the arrival of emergency assistance.
There are also long term effects of food shortage. These include increase in the price of food as a result demand and supply forces. Increasing cost of food production due to the increase in fuel prices coupled with persistent drought in grain producing regions has contributed to the increase in the price of food in the world. Increase in oil price led to increase in the price of fertilizers, transportation of food and also industrial agriculture. Increasing food prices culminated in political instability and social unrest in several nations across the globe in 2007, in countries of Mexico, Cameroon, Brazil, Burkina Faso, Pakistan, Egypt and Bangladesh among other nations (Kamdor, 2007).
Solution to problem of food shortage
There are some solutions to the problem of food shortage. There is need to reduce production of carbon emissions and pollution to reduce the resultant climatic change through concerted and individual efforts. There is need to invest in clean energy such as solar, nuclear, and geothermal power in homes and industries, because they don’t have adverse effects on the environment (Kamdor, 2007). Rich nations should help poor nations to develop and use clean and renewable energy in order to stabilize green house emissions into the atmosphere (Watson, nd). Government need to work in consultation with climatic bodies, World Bank and the UN to engage in projects aimed at promoting green environment.
Conclusion
Causes of food shortage are well known and can be solved if appropriate measures to solve the problem are taken and effectively implemented. Environmental causes of food shortages are changes in climatic and pollution due to human activities such overgrazing!$ ^4 !$ and deforestation which can be controlled through legislation.
(Adapted from http://www.paypervids.com/food-shortage-causeseffects-solutions/Acesso em:14 fev 2017)
Glossary:
1. unrest – disagreement or fighting between different
groups of people
2. soaring – something that increases rapidly above the
usual level
3. yield – to supply or produce something such as profit or
an amount or food
4. overgrazing – excessive use of land where animals feed
on grass
The sentence “the change in climate is majorly caused by human activities” means that
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Uma rampa, homogênea, de massa m e comprimento L, é inicialmente colocada na horizontal. A extremidade A, dessa rampa, encontra-se acoplada a uma articulação sem atrito. Na extremidade B está sentado, em repouso, um garoto, também de massa m. Essa extremidade B está presa ao chão, por um fio ideal, e ao teto, por uma mola ideal, de constante elástica k, conforme ilustra a Figura 1.

Quando o garoto, que neste caso deve ser tratado como partícula, atinge a extremidade A, a mola se encontra em seu comprimento natural (sem deformação) e a rampa estará em repouso e inclinada de um ângulo !$ θ !$ . Considerando g o módulo da aceleração da gravidade local, nessas condições, a velocidade do garoto em A, vale
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Uma fonte sonora A, em repouso, emite um sinal sonoro de frequência constante !$ f_A = 100 !$ Hz. Um sensor S desloca-se com velocidade constante !$ V_S = 80 !$ m/s, em relação à Terra, sobre um plano perfeitamente retilíneo, em direção à fonte sonora, como mostra a Figura 1.

O sensor registra a frequência aparente devido à sua movimentação em relação à fonte sonora e a reenvia para um laboratório onde um sistema de caixas sonoras, acopladas a três tubos sonoros, de comprimentos !$ L_1 !$, !$ L_2 !$ e !$ L_3 !$ , reproduz essa frequência aparente fazendo com que as colunas de ar desses tubos vibrem produzindo os harmônicos apresentados na Figura 2.

Considere que o sensor se movimenta em um local onde a velocidade do som é constante e igual a 320 m/s, que os tubos sonoros possuam diâmetros muito menores do que seus respectivos comprimentos e que a velocidade do som no interior desses tubos seja também constante e igual a 320 m/s. Considere também que a fonte A e o ar estejam em repouso em relação à Terra. Nessas condições, é correto afirmar que os comprimentos !$ L_1 !$, !$ L_2 !$ e !$ L_3 !$ , respectivamente, em metros, são
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