Imagine a world with 868 million hungry people, 200 million of which are malnourished children under the age of five. Now imagine that world also has an abundant food surplus. That world is not imaginary—we live in it.

By 2050 the global population will grow to nine billion and many are asking how our agricultural system will yield enough crops to feed all those mouths. Current research suggests that we already produce enough to feed nine billion people. Feeding such a population equitably and sustainably, however, is a different and more challenging problem. Scientists at UC Berkeley are making important strides in understanding the impacts of today’s prevalent agricultural methods and in developing improved food production strategies for the future.

The Green Revolution

Photo credit: Whitney Merritt

Though the prospect of feeding an ever-increasing world population is certainly daunting, the issue is not new and has been tackled before, most recently during the mid-twentieth century. In a remarkable series of technological achievements known as the “Green Revolution,” scientists engineered crops capable of producing dramatically higher yields and introduced them to regions suffering from food shortages.

For a large part of human history, producers needed only to expand a cultivated area in order to achieve greater production, though much of agriculture remained subsistence-based. After the Industrial Revolution a shift towards commercial-based agriculture occurred, the population continued to increase, and the introduction of global markets transformed the food production landscape. By the early part of the 1940s, the problem of massive food shortages was internationally recognized as a global crisis.

Aiming to boost crop production in impoverished countries, agronomist Norman Borlaug began developing wheat varieties that were bred to respond to fertilizer application by producing elevated yields. Soon, the Rockefeller Foundation and the Ford Foundation joined the effort by funding scientific research and promoting a series of global initiatives. The chief effort of these initiatives involved developing, importing, and distributing fertilizers and hybridized seeds that were selected for enhanced fitness and extraordinary production. One such hybrid, IR8, informally dubbed “Miracle Rice,” found much success in parts of Asia and India. When grown under optimal conditions that included fertilizer and pesticide application, IR8 produced ten times the yield of traditional rice. Global production ballooned and rice prices dropped dramatically.

Green Revolution proponents celebrated in 1985 when worldwide cultivation of cereal grains (maize, wheat, and rice) more than doubled as a result of the new technologies. While the benefits of the Green Revolution were immediately clear, it took several decades to fully understand its ramifications.

The Green Revolution’s cost

The Green Revolution accomplished its goal to increase food production, saving the lives of billions who would otherwise have starved. However, its net long-term benefits are less clear because of the food system’s inherent complexity and its interconnection with the environment, health, nutrition, and politics.

Agricultural energy use provides a simple example. Increased agricultural output during the Green Revolution required increased energy input. One of the inputs, petroleum, enables the manufacture of fertilizers and pesticides and the transportation of harvested foods around the globe. The use of petroleum also elevates greenhouse gas concentrations in the atmosphere, contributing to global climate change and leading to great costs in terms of ecological health and continuity. Currently, industrial agriculture is the source of one-third of all greenhouse gas emissions, according to a recent report on climate change by the Consultative Group on International Agricultural Research.

In addition to the environmental harm caused by the production of pesticides, pesticide use itself has elicited worry among UC Berkeley researchers. In the late 1990s and early 2000s, Tyrone Hayes, Professor of Integrative Biology at UC Berkeley, discovered that a widely used synthetic herbicide called Atrazine caused male frogs to exhibit female biological characteristics when exposed to levels deemed safe by the US Environmental Protection Agency. The controversial debate surrounding the use of Atrazine continues, with Hayes at its center (see “Murky Waters,” BSR Spring 2011), standing as a testament to the complicated relationship between agriculture and ecology.

Recent research also suggests that some of the more subtle practices inherent to large-scale industrial agriculture may be just as damaging to the environment as pesticides and other petroleum-based inputs. In particular, scientists are raising concerns about commercial agriculture’s widespread adoption of monocultures, large areas of farmland where only a single crop is cultivated. Claire Kremen, professor in the Department of Environmental Science, Policy and Management, researches the effects of industrial agricultural practices on pollinators like honeybees, bats, butterflies, birds, and insects. These species are crucial to crop fertilization and reproduction. Kremen’s research indicates that one-third of all fruits and vegetables are pollinator-dependent species.

In order to thrive and reproduce, pollinators need plants to bloom throughout the year. They also require nesting habitats such as undisturbed soils, holes in wood, and abandoned rodent burrows. “None of these needs fits very well with the lack of trees and the tilled soil of monoculture plots,” Kremen says. “When you create monocultures, you’re really doing two counterproductive things at once. Firstly, you are forcing out native non-honeybee pollinators by eliminating their nesting habitats. At the same time, you’re creating a much higher demand for pollinators in general, because plants in monoculture plots bloom simultaneously, thereby necessitating many pollinators.”

The creation of monocultures has spurred the loss of native pollinators and led to the industrial agricultural practice of importing and actively managing non-native, European honeybee colonies to accomplish crop pollination. Such practices have resulted in problems of their own. These managed honeybee colonies are increasingly falling prey to an epidemic known as Colony Collapse Disorder, a recent phenomenon in which worker bees of a colony abruptly and mysteriously die en masse. In each of the previous five years, data from the United States Department of Agriculture (USDA) indicate an approximately 30 percent loss in managed honeybee populations across the US, prompting worries about the commercial and ecological sustainability of managed beekeeping. Without either managed honeybees or native pollinators, entire economic sectors run the risk of being lost. For example, Kremen worries specifically about the US almond crop, which is valued annually at three billion dollars and is largely dependent on honeybee pollination.

Yield gaps and research gaps

Current food production practices adversely affect ecological health, but are alternative agricultural practices capable of producing enough to feed nine billion people? The answer may turn out to be yes. UC Berkeley researchers have demonstrated that in many ways, alternative agricultural practices and their associated flora can be as productive as large-scale, industrial agriculture, and possibly even more so.

In collaboration with an international research team, the Kremen lab showed that the presence of native bees increases the pollination efficiency of imported honeybees. The research took place in California almond orchards, where scientists documented altered honeybee behavior: the honeybees were more effective crop pollinators when wild bees were present. Kremen found similar results in another study published in Science in February, in which she and 50 collaborating researchers examined a vastly expanded data set covering 41 different types of crop systems on six continents. They found that the proportion of flowers that developed into mature fruits or seeds increased by a factor of two when the flowers were visited by wild insect pollinators than when visited by honeybees.

Researchers compared pollen deposited on flower stigmas by honeybees to pollen deposited by wild insects, and found a curious result. Honeybees deposited significantly more pollen than wild insects but this increased deposition did not result in an increase in fruit production, leading the researchers to conclude that it is the quality of pollination, not the quantity of pollen, which is the decisive factor. Kremen and her coauthors explain that poor-quality pollination can arise when insect foraging behavior leads to pollen transfer among flowers of the same plant. The effectiveness of wild insect pollinators may be due, in part, to greater cross-pollination.

IR8, a semi-dwarf rice variety developed by the International Rice Research Institute in 1966, requires the use of fertilizers and pesticides but produces ten times the yield of traditional rice cultivars.

These promising findings suggest that the high-quality pollination supplied by wild insects makes alternative agricultural systems more efficient than large-scale, industrial monoculture. However, comparing crop yields from industrial practices to those from alternative practices remains a challenge. Insufficient funding has gone towards studying production methods that differ from current industrial practices. According to a study from UC Berkeley conducted by Albie Miles, PhD candidate in the Department of Environmental Science, Policy, and Management, and Liz Carlisle, PhD candidate in the Department of Geography, the 2011 research and development portfolio for alternative farming systems constitutes less than three percent of the total USDA Research, Education, and Economics budget. For this reason, crop yields continue to be openly debated in the scientific community.

In 2012, Nature published a study conducted by researchers at McGill University and the University of Minnesota that performed a large-scale meta-analysis to compare organic and conventional farming. The study estimates yields from organic farms, which use many alternative farming practices, to be between 5 and 34 percent lower than those from industrial monoculture farms, depending on location and product, but stresses the need for further study and understanding.

The Kremen lab is currently reviewing some of the meta-analysis techniques used in the study. “We have some concerns about how they conducted the meta-analysis,” Kremen says. “We think that the original analysis suggests, with a greater certainty than is merited, a relatively large difference between organic and conventional yields.” The re-analysis done by the Kremen lab has found both a smaller difference and greater uncertainty about the estimated difference, suggesting that organic and conventional systems cannot currently be distinguished in terms of productivity.

While the question of yield remains contested, some researchers are focusing on comparing organic and conventional agriculture using other metrics. Miles focuses not on the evaluation of yields in organic agriculture, but rather on the ecological impacts of a wide range of practices referred to as diversified farming systems. These methods integrate functional biodiversity into agricultural landscapes. In a recently published quantitative review co-authored with Kremen, Miles compares biologically based, diversified farming systems with chemically-based, biologically-simplified farming systems. They found that the former systems support substantially greater biodiversity, increased soil water-holding capacity, improved soil quality, elevated carbon sequestration, and better resilience to climate change.

Pollinators such as this European honeybee are crucial to crop fertilization and fruiting.

At the same time, Miles is also doubtful of the existence of a yield gap between diversified and conventional farming systems. “There is inadequate evidence at present to support the claim that diversified farming systems reduce yields per area,” he says. According to Miles, any actual discrepancies can be attributed to the legacy of the Green Revolution. “Conventional industrial agriculture may produce higher yields of some crops, principally cereals, but has been able to do so only because of the 60-plus years of capital intensive research directed exclusively toward increasing productivity of grain crops.” Both Miles and Kremen believe that research on diversified farming systems warrants significantly greater public investment from the federal government and international agriculture centers. With this support, the authors argue, any existing production gaps could be closed. At the same time, the empirical basis for the management of more multi-functional agricultural systems could be developed further.

This opinion is shared by others, including leaders working to reform food policy. Miles’s advisor, Professor of Agroecology Miguel Altieri, along with Dr. Eric Holt-Giménez, Director of the Institute for Food and Development Policy (also known as Food First) in Oakland, California, published a paper in the journal Agroecology and Sustainable Food Systems in December of 2012. They argue in favor of small farmers and are concerned about their disappearance: “The first Green Revolution drew in millions of smallholders [small-scale farmers], many of whom were forced out of farming by larger, better capitalized farmers, or went bankrupt after their soils became sterile and subsidized credit disappeared.” According to Altieri and Holt-Giménez, those small-scale farmers have been left with an inability to compete on the global market and a loss of access to land.

The potential benefits of small-scale farms and more sustainable cultivation practices are particularly compelling in the developing world, where severe food shortages continue to exist even in the present state of abundance. Altieri’s research estimates that traditional farmers manage only 10 to 15 percent of the 960 million hectares of arable land in Asia, Africa, and Latin America, but produce a significant majority of the rural population’s staple crops, including cassava, beans, and potatoes.

Solutions for the future

As more and more research on UC Berkeley’s campus becomes focused on sustainable agricultural practices, stakeholders within the field are hoping to nurture a fruitful environment for collaboration. This desire has resulted in the creation of an exciting new organization called the Sustainable Food Systems Institute, which will connect and coordinate efforts within the College of Natural Resources, the Graduate School of Journalism, Berkeley Law School, and the Goldman School of Public Policy. Though still in its early stages of development, the institute will aim to address global concerns and work to transform the food system into one that is sustainable for future generations.

Kremen is excited about the new initiative, of which she is the co-director. “The institute’s first activity will be a large conference that brings together faculty and external participants interested in the food system,” she says. “The goal will be to break down barriers and territories in order to develop an agenda.” Kremen hopes the institute will serve as a nexus where diverse segments of the UC Berkeley community can meet to develop research plans, policy recommendations, and public outreach campaigns. “To address the global food system’s problems, we will need to work on a lot of different fronts at once,” Kremen says. “We must take a holistic look and that makes it incredibly challenging.”

Ultimately, nine billion is a formidable number of people to feed, and it is clear that the solution to global hunger is going to involve more than a single silver bullet. With the upcoming launch of the Sustainable Food Systems Institute and other cross-disciplinary organizations like it, the puzzle of equitable food production may finally be approaching a solution. Connecting the diverse pieces of environmental preservation, ecological health, and public policy could create powerful, lasting alliances, the advantages of which may prove to be innumerable.