The Cost of Crops
Rich soils produce abundant food crops, but is there a hidden cost?
It Seemed Like A Good Idea At The Time
Many people today don't realize how common periodic famines used to be all around the world. There was a time when famine was just considered part of the natural cycle, something that came along every few decades. Times change and now if people think of famine at all, they see it as a "Third World Problem". Famine is thought of as something that occurs in Africa, something that industrial nations with all their technology have escaped. To some extent this is true. Food shortages in many parts of the world have become rare thanks to improved agricultural yields and improved technologies for transporting and storing food--people didn't always have freezers! But as the human population continues to grow and more food is necessary, people are realizing that some of our increased crop yields have come with an unexpected price.
- Earth's Nitrogen In The Balance from AMNH https://www.youtube.com/watch?v=gt4V-vB4vcY
Use the resources below to answer the following questions:
- How does nitrogen from the atmosphere get into the Earth's soil? How long has this process been going on? What organisms benefit from this process?
- What activities of humans are changing the balance of the nitrogen cycle? What are the benefits of these human activities? What are the costs of these activities?
- Why do some people feel nitrogen fertilizer is a short-term solution? Do you agree with this evaluation? Be as specific in your reasoning as you can be.
- Do you think the original source of the nitrogen in fertilizer makes a difference in how it affects the nitrogen cycle? Why or why not?