Global Agriculture

Goal. The purpose of this lab is to explore the capacity of planet Earth to provide food to the growing human population. The questions about food sustainability below do not have easy answers. In nearly every case, strong arguments can be made in several directions. Your job is to grapple with these difficult questions, using quantitative information to support your claims whenever possible.

Upload a write up with answers to each numbered question. You should upload your completed assignment as a .doc,.docx or .pdf file on the “Assignments” page of the course Canvas site. Please use the file naming convention “lastname_lab3.docx”. Failure to use this convention and/or late assignments will incur a point penalty.

1 (4 points). According to Montgomery (2007) about 1.5 billion hectares (1 hectare = 104 m2) of the planet are naturally suitable for growing crops. At present this entire area is cultivated (cropland). What fraction of the land surface is this?

2 (12 points). Using the medium-projection UNEP global population dataset from Lab 1 (part 2), calculate the global per capita cultivated land (cropland area per person) from 1950 to 2050. This is an estimate of the amount of land required to feed the average person on Earth. Make a graph of this calculation against year. (Remember that all figures should have a number and caption.)

3 (12 points). Do you think the area of land available to grow crops productively will increase, decrease or stay the same during the next 40 years? Explain your answer in a paragraph.

4 (12 points). Given modern (post-Green Revolution) farming practices, can the planet’s cultivated land sustain the expected 2050 population? Why or why not? (Answer in a paragraph.)

5 (5 points). Now, let’s explore the limitations of this calculation. Obviously, not all agricultural land is equally productive due to variations in soil quantity and quality, water availability, climate, etc. This will mean that some places will be far better able to yield crops than others. However, there is an even larger issue at play. Is all of the cropland on the planet used to grow food for people? What are other significant uses of cultivated land?

6 (15 points). Now, do some research. How much of the land area of the United States is cropland (give the number in hectares or m2 and calculate its fraction of the total U.S. land area)? What is the per capita cultivated land area in the U.S.? Be sure to cite sources for your data in your answers.

7 (10 points). What percentage of the cropland in the U.S. is used to grow food for humans, and what are the percentages for other types of crops? Be sure to cite sources for your data in your answers.

8 (15 points). Given your answers to questions 3-7, can you make any statements about the sustainability of meat and dairy consumption in the U.S. and globally? From an environmental standpoint, should humans consume less (or no) meat? If you can justify your answer quantitatively (citing sources), so much the better. (Answer in a paragraph.)

9 (15 points). Given your answers to questions 3-7, can you make any statements about the sustainability of using cropland to produce biofuels in the U.S. and globally? If you can justify your answer quantitatively (citing sources), so much the better. (Answer in a paragraph.)

Reference

Montgomery, D.R., 2007, Is agriculture eroding civilization’s foundation?, GSA Today, v. 17, n. 10, doi:10.1130/GSAT01710A.1, p. 4-9.