If someday soon, when wars break out over water and the price of cereal skyrockets, don’t say Lester Brown didn’t warn you.

Brown, founder of the Worldwatch Institute and president of the Earth Policy Institute, gave a lecture titled “Plan B: Rescuing a Planet Under Stress and a Civilization in Trouble,” Saturday to a crowd that filled Campbell Hall past capacity. Brown used his speech to argue that if current environmental trends continue, the global economy will eventually fall apart.

“Right now we are on the edge of one of history’s hinge points, after which nothing will be the same,” Brown said. “I believe a major global wake-up call will come within a year in the form of rising food prices.”

Brown said that China, which has a population of 1.3 billion people and an $80 billion trade surplus, will soon “give in to world markets for grain, which it will import on a massive scale.” Brown said China’s domestic grain production has been dropping due to a loss of cropland to industrial and residential purposes, as well as soil erosion.

“When China begins to import all this grain, competition for grain markets like the U.S. would increase dramatically, pushing up prices for American consumers and the world,” said Brown. “This could destabilize smaller countries that depend on grain imports.”

Brown said the amount of grain currently consumed worldwide per year exceeds the amount produced by 105 million tons. He said the fact that grain stocks are at a 30-year low is proof of this.

“Socialism collapsed because it didn’t allow the market to tell the economic truth,” Brown said. “Capitalism may collapse because it won’t allow the market to tell the ecological truth.”

In addition to a loss of croplands, Brown said the diminishing amount of water available for use in irrigation “puts the squeeze on agriculture.”

“It takes about 5,000 liters of water to produce the food we consume every day, and we’ll soon be facing water shortages,” said Brown. “Future wars in the Middle East may be fought over water instead of oil.”

To solve these problems, Brown said “we must stabilize the world’s population, initiate a full-court press to increase worldwide water productivity and cut carbon emissions.”

Brown said global warming, which he blames partly on carbon emissions, hurts grain production. He said for every increase in temperature by one degree Celsius, there is a 10-percent fall in grain yields. He advocated the production of more fuel-efficient cars and the increased use of renewable energy sources.

Brown said the technology to make the necessary changes exists, but that there is a lack of motivation to do so.

“We can change quickly if people feel the urgent need to do so,” Brown said. “Unfortunately, I think our political leaders and the media have become too preoccupied with terrorism, when these problems can prove to be much more dangerous.”

Crowd reaction was generally positive, but some members of the audience expressed confusion. Katie Gilliam, a sophomore psychology major from UC San Diego, said she wondered what individuals could do to help the problem.

“I agree with his main points on what broad [changes] need to happen,” Gilliam said. “The question that kept running through my mind was, ‘What I can do on a smaller scale to help?'”

Junior environmental studies major David Hochart said he agreed with Brown’s ideas, but thought most people would be unreceptive to his suggestions until the situation gets worse.

“I think his ideas are practical and future-oriented,” Hochart said. “Unfortunately, I don’t think his message will get through to people until a major warning bell sounds.”