Is biodiversity the future of farming?

Industrial agriculture faces painful challenges: the end of cheap energy, depleted water resources, impaired ecosystem services, and unstable climates. Scientists searching for alternatives to the highly specialized, energy intensive industrial system might profitably look to the biological synergies inherent in multi-species systems, according to an article in the March-April 2007 issue of Agronomy Journal. The paper's author, Fred Kirschenmann, Distinguished Fellow for Leopold Center for Sustainable Agriculture, Iowa State University, states that industrial agriculture assumes:

 

  • Production efficiency can be best achieved through specialization, simplification and concentration
  • Therapeutic intervention is the most effective way to control undesirable events
  • Technological innovation will always be able to overcome production challenges
  • Control management is the most effective way to achieve production results
  • Cheap energy will always be available

As we enter the 21st century most, if not all, of these assumptions must be questioned. The degraded condition of ecosystem services was detailed in the UN "Millennium Ecosystem Assessment Synthesis Report" (2005). The report also anticipates that during the next 50 years demand for food crops will grow by 70 to 85% and demand for water by between 30 and 85%.

Volatile weather conditions predicted to be part of emerging climate change will make it difficult to sustain highly specialized cropping systems which require relatively stable climates. To keep agriculture productive, farmers likely will need to adjust quickly. If we can design farming systems that are less energy intensive, more resilient in the face of unstable climates, and that begin to out-produce monocultures by virtue of their multi-species output, the economic advantages of such complex farming operations might be an incentive to change.

A few farmers already operate successful, complex farming systems based on biological synergies and adaptive management. One is Takao Furuno's duck/fish/rice/fruit farm in Japan. He produces duck meat, duck eggs, fish meat, fruit, and rice without any purchased outside inputs, using a highly synergistic system of production on the same acreage where he previously only produced rice. And, in this new system, his rice yields have increased up to 50% over previous yields from an energy-intensive rice monoculture. Joel Salatin, of Polyface Farms near Swoope, VA, has developed a rotational grazing production system featuring pastures containing at least 40 varieties of plants and numerous animal species. Salatin's farm uses little fossil fuel, yet the farm is highly productive. The 57-hectare farm annually produces 30,000 dozen eggs, 10,000 to 12,000 broilers, 100 beef animals, 250 hogs, 800 turkeys, and 600 rabbits.

A study by George Boody and colleagues has calculated, on a watershed basis, that diverse, synergistic farms can be profitable and simultaneously benefit the environment. They showed that when farms are converted from corn/soybean monocultures to more diverse operations, net farm income can increase by as much as 108% while generating significant environmental and social benefits. Principles that might guide postmodern farms are almost diametrically opposed to those supporting industrial agriculture. They may need to:

  • Be energy conserving
  • Feature both biological and genetic diversity
  • Be largely self-regulating and self-renewing
  • Be knowledge intensive
  • Operate on biological synergies
  • Employ adaptive management
  • Feature ecological restoration rather than choosing between extraction and preservation
  • Achieve optimum productivity by featuring nutrient-density, and multi-product synergistic production on limited acreage

This article has been adapted from a news release issued by American Society of Agronomy