The explosion set to reach 7,000,000,000.

• Position: Population

As the global population increases, so does the number of mouths to feed. The good news is that, in addison to providing food, innovations in sustainable agriculture can provide a solution to many of the challenges that a growing population presents.

"Agriculture is emerging as a solution to mitigating climate change, reducing public health problems and costs, making cities more livable, and creating jobs in a stagnant global economy," asserts Danielle Nierenberg, senior researcher and codirector of Worldwatch Institute's Nourishing the Planet project, a two-year evaluation of environmentally sustainable agricultural innovations to alleviate hunger.

This year, the world's population will hit 7,000,000,000, according to the United Nations. Not even demographers can forecast how many people will be added to world population over the coming century, notes Robert Engelman, executive director of Worldwatch, Washington, D.C. As more women and their partners gain access to reproductive health services and manage their own childbearing, average family size has fallen significantly in recent decades and could continue to do so, assuming expanded support for reproductive health and improvements in women's autonomy and status.

The likelihood of continued population growth for some time, however, remains high--and that will add to the need to harness the ingenuity of human beings to sustain the planet and its people. "We'll have to learn how to moderate our consumption of materials and energy and to jumpstart new technologies that conserve them," Engelman indicates. Innovations in farming will be among the most important: with planning, agriculture not only can operate as a less-consumptive industry, but one that works in harmony with the environment. Declares Nierenberg, "Everyone is in this together in more ways than one."

The UN predicts that 65% of the global population will live in cities by 2050. Urban agriculture provides an increasing number of city residents with fruits and vegetables, leading to improved nutrition and food security. Urban farms already are gaining popularity around the world...