Q：
    How can you dismiss the environmental effects that the Green Revolution has had? The chemical and seed technology companies have a lot at stake in you believing that this is the only way to feed the world. Why aren’t people involved with farming without chemicals and biotechnology part of this conversation? There is certainly proof that organic can feed the world. Intensive agriculture depletes the soil, and do remember that there are as many obese people in the world as there are hungry, so we are obviously doing something wrong. In America we currently produce double the calories that each person needs. Hunger is not only about production, it is about distribution and politics.
Rachel Berger

A：
    I do not dismiss the environmental effects. I take them seriously, and outlined them at some length in this blog post. It is beyond question that producing food for seven billion people has done massive damage to the planet, and that creating a more sustainable agriculture, even as we ramp up food production to meet rising demand, is one of the urgent challenges of our time. As you say, how food is distributed and how people eat — too much in some places, too little in others — are major issues, although they were beyond the scope of my recent article. I also agree with those readers who point out that food waste is a big issue.
    But my reporting has not turned up “proof that organic can feed the world” — quite the contrary. Experts point out that organic production standards rule out the use of inorganic nitrogen fertilizer, and without added nitrogen, it would be mathematically impossible to feed the current world population, much less a future population of 10 billion. Vaclav Smil outlines the situation in this piece. Agronomists told me that the crucial task for them is to take as many good ideas as they can from organic agriculture and related movements and transfer those into the conventional food system. In my Sunday blog post, I discussed one attempt to do this, through a technique called conservation agriculture, but clearly more efforts are needed in this direction.

Q:
    Perhaps the most significant unnamed driver of our looming food crisis is the massive use of grain, water, chemicals, and energy to produce meat and dairy products. For a start, please read the executive summary from the F.A.O.’s stunning report, “Livestock’s Long Shadow.”
Shams, Kensington, Calif.

A:
    Thanks for the link to what is indeed an interesting report. Several readers have raised the question of why I didn’t discuss the meat issue in my article. The point is well taken, in that rising meat consumption is a massive driver of demand in the food system. It is the reason China has a become a big importer of Brazilian soybeans, to cite just one among many examples of the environmental cost of meat. I dodged the subject in my piece partly because we have written so much about it in the Times over the years. But I avoided it for another reason, too. So far as I can determine, no one has come up with any public policy that would substantially lower the demand for meat and, at the same time, has a realistic prospect of being adopted.
    My analysis of this was influenced some years ago by a speech given in Des Moines by Sir Gordon Conway, then a senior scientific adviser to the British government. He started by acknowledging that lowering meat demand would ease many of the world’s food problems, but then he said, “I just don’t think it’s going to happen.” He pointed out that the world’s governments are likely to let consumer sovereignty prevail on this, as they have already for many decades, and the world’s consumers are not abandoning meat — they are moving in the other direction.
    It’s easy to see why politicians stay away from this topic. If they proposed policies that might actually reduce demand, such as high taxes on meat, they would probably get run out of town with pitchforks. Assuming the trend lines do not change, rising consumption of meat represents a demand on the food system that is going to have to be met, at least in the coming few decades. One can raise interesting speculations about the distant future; it really is hard to envision a planet of 10 billion people in the year 2100 eating the way that Americans eat today. I don’t really have a clue what happens between now and then; but take a look at Michael Specter’s recent New Yorker piece suggesting that we could wind up growing our meat in test tubes. In the meantime, if anybody has ideas for a public policy that can actually pass and would drastically curtail meat-eating, the floor is open for nominations.

Q:
    I wonder if we, as a nation, have any sort of plan or strategy for how to deal with either the possibility of grain shortages here or the certainty of price spikes to come. Is anyone in Washington even thinking about this, or will we be left to what is euphemistically referred to as “market-based solutions,” i.e. price gouging, profiteering by speculators and growing domestic hunger?
Keith, Portland, Ore.