Question

The current population of Tanzania is 49.3 million with a population growth rate of 2.53% per year. The average annual agricultural yield in Tanzania is 8950 kg/ha (where "ha" means hectare, which you can think of as a metric acre), a yield that is comprised of both grains (e.g. maize/corn) and tubers (e.g. cassava root) in a 1:1 ratio. The total amount of cropland farmed in Tanzania is 4,500,000 ha. The average agricultural output has increased at a linear rate of about 1.3% per year for the last five years or so. Ideally, one person should have a caloric intake of at least 2000 kcal per day in order to maintain their life. 1 kg grain supplies 3000 kcal; 1 kg tubers supplies 1000 kcal. Use the equations from our mini-lecture and the linear growth equation from the last module's quantitative assignment, to answer the following questions. You will also have to do some conversions for which you won't find specific equations. If Tanzania can currently feed 110 Million people, in what year will they cease to be self-sufficient in food? In other words, when will they need to begin importing food?

Hint: Plot both (i) population growth and (ii) food growth on the same set of axes for a span of 100 years or so (a point every 10 years should be enough for you to make a determination). The point where the two lines cross is the point after which they would need to start importing food. A spreadsheet program such as Excel may help though you could simply plot them on paper. Alternatively, you could use your scientific graphing calculator (if you have one) to determine the answer. The current year is 2,018.

Answer 1