UCSB Ecologist’s Paper Published in Nature

In 2050, the world’s population is projected to reach nine billion. All nine billion people need food and resources.

Christian Balzer, a graduate student in UC Santa Barbara’s Department of Ecology, Evolution, and Marine Biology joined U.S., German, Canadian, and Swedish researchers in asking how to feed this booming population without devastating the environment. Their suggestions were published this month in the journal Nature.

The article, Solutions for a Cultivated Planet, lays out strategies for meeting the daunting challenge of feeding nine billion people while protecting the environment. It reports that over a billion people currently experience chronic hunger despite the fact that more land is farmed now than ever before.

Historically, those interested in food security ignore agriculture’s environmental toll while conservationists ignore escalating food needs. “We looked at these issues as two sides of the same coin,” said Balzer.

Health and environmental quality go hand in hand, according to Balzer. “If we do it right, we can make the world better for people and the environment,” he said.

Agriculture occupies 38 percent of the Earth’s surface, the largest single use of land. If it cannot occupy sustainably, people face major climate change, biodiversity loss, and devastated fresh water and land.

To avoid these impacts, the researchers set environmental goals: cut agriculture’s greenhouse gas emissions by 80 percent, reduce the loss of biodiversity and natural habitat, and end water pollution from agricultural chemicals. And those are just discussion starters.

With goals in mind, the team laid out five strategies.

First, the expansion of agricultural land must end, especially expansion into tropical areas. These areas often have lower crop rates than their temperate equivalents while their cultivation severely disturbs the globally important rainforests.

Agriculture could expand within fallow fields while growers also heighten production on healthy, preexisting farmland, according to the article, which also suggests reallocating land cultivated for animal feed and biofuels to food for humans. Only 62 percent of the world’s crops are meant for human consumption. The other 38 percent is used for animal feed (35 percent) and biofuels (3 percent).

More grazing land for animals means less land available for crops that efficiently feed humans, subsequently lowering global food capabilities. Animal feed crops inefficiently sustain humans by nourishing animals for meat and dairy products. The more bodies the original plant goes through, the less energy it provides consumers.

Balzer had another strategy up his sleeve. “Urban farming is going to be one of the solutions that we can use to intensify agriculture where humans live rather than expanding out into natural areas,” he said.

To compensate for food losses from decreased expansion, growers must maximize yields. The research team suggests better worldwide deployment of existing crop varieties and better crop management techniques.

Balzer proposed using micro-financing to spread resources. Small loans would help farmers in developing countries procure crop management tools like improved irrigation and fertilizer. The loans would be repaid with the extra income from increased harvests.

Beyond maximizing harvests, producers need to intensify growth. Food resources must double in the next few decades to meet population growth.

To succeed on both ends of the issue, intensification must happen along with responsible use of water resources, nutrients, and chemicals. Sustainability is key when agriculture has to share the world’s water with a continually growing population and its resource demands. Where water is scarce, proper land and water management can increase sustainability. Some crops use less water while others seemingly sponge it up. Growers must also impede evaporation both on and off the field. Techniques range from monitoring evaporation during transport to improving mulching and tilling practices on fields.

Chemical fertilizers, manure and, leguminous crops have intensified crop growth but have also led to “nutrient pollution.” Phosphorous and nitrogen from fertilizers along with other farming chemicals leech into water bodies and contribute to climate change. Improved manure management and recycling can capture nutrients prior to their leeching.

Many of the article’s solutions were aimed at growers, but what can consumers do?

People should know the environmental costs of their diets and waste. “I’m not suggesting everyone become vegetarian, but watching meat consumption will help,” said Balzer. Eating a more plant-based diet will reduce one’s environmental footprint while increasing land available for food crops.

Unfortunately, according to the article, the Food and Agriculture Organization found that one third — and some estimates are as high as one-half — of food is never consumed. Reducing overall waste, especially in very resource-intensive products like meat and dairy, could increase food availability.