According to a recent United Nations report, the world population has reached 7 billion people. Uma Ramakrishnan, assistant professor of environmental science, gives her opinion on how human population growth will affect our world.
Q: How will human population growth affect the environment in general?
A: In general, this trend has been continuing. Some of the major impacts would be water because we already don’t have enough fresh water. I think food is less of an issue. Space will be a problem, depending on the region. Most of the growth is in the tropics, so we are less likely to see this here, but south and southeast Asia are already extremely densely populated. That density increase is going to impact quality of life and land value, and it will increase poverty.
Q: Do you think that humanity will continue to grow at this rate?
A: The projections are that by about 2050 the trend is going to peak. Right now, even though the population is increasing, the percent increase has been dropping. It is going to level off roughly between 9 and 11 billion people. Based on what we are seeing now, it would be closer to 9 billion than to 11 billion, so we have a ways to go. The population will eventually level off.
Q: How high could the population get before it became unsustainable?
A: Depending on who you are talk to, we are already above what one would consider sustainable. Most people are talking about cultural carrying capacity, which is how much we can sustain while continuing to meet quality of life. We can live under extremely dense conditions with a fraction of the food that we have today. Do you want that? That’s really the question. Are we all going to eat ourselves out of house and home? No, I don’t see that happening. This is something that has been predicted for centuries and it hasn’t happened. I’m not saying that it wouldn’t have serious negative consequences, some of which we are already seeing, but we’re not all going to die. The U.S. is predicted to have a drop in population, so we are less likely to feel the effects directly. Parts of Europe already have negative population growth. The growth areas will be in Asia and Africa. Asian populations are stabilizing and leveling off. The problem is that they already have very high populations right now.
Q: How does human population growth compare to the population growth in other animals?
A: There are some animals that exhibit the classic boom and bust, where you see the population increase and then crash. Essentially, it’s following animal cycles and food availability. In many cases, especially in islands, the population increases to an incredibly high level and crashes because the food is completely depleted. Humans are not likely to see that because we are able to change the environment to support more and more people. I’m not saying that you don’t see these crashes, but most of the crashes that you see historically on a larger scale have been tied to disease. We have had obviously famine, but mass starvations in famine conditions are really tied to wars where people are intentionally blocking access to food to control population or to control behavior. I’m not saying that people are not struggling to get food, but you will not see the boom and bust that you see in the wild.