Biodiversity for Resilience Against Natural Disasters

As climate shocks increase in frequency and intensity, agricultural biodiversity—the variety of species of plants, animals, and microorganisms used for agriculture and food production—is an increasingly important part of resilience building.

Climate change is increasingly putting pressure on farmers and the global food systems, according to researchers from the International Food Policy Research Institute (IFPRI), the Consultative Group for International Agricultural Research (CGIAR), and the transdisciplinary International Panel of Experts on Sustainable Food Systems (IPES). These groups and others are highlighting the importance of resilience—an ecosystem’s capacity to resist or recover from stress, shocks, and disturbances—for the security and productivity of the world’s food and farming systems in the face of climate change.

Resilience matters most for feeding the world’s growing population as the climate changes, according to these leading food security and agriculture groups, and agricultural biodiversity can be key to building it.

The U.N. Food and Agriculture Organization (FAO) defines agricultural biodiversity as the diversity among plants, animals, and microorganisms directly or indirectly used for agriculture and food production.

Agricultural biodiversity exists at three levels, all of which are important for climate adaptation. On a regional level, agricultural biodiversity involves farms in proximity to one another growing and supporting a range of different crops and species. At the farm level, crop diversity can mean farmers employ sustainability measures like crop rotation to maintain soil health, or agroforestry, or intercropping. Farmers utilize genetic diversity of crops when they grow several different species of a crop rather than one variety.

Research from CGIAR, FAO, and others over last two decades has concluded that biodiversity significantly contributes to resilience, and furthermore that a combination of biodiversity-increasing strategies often yields the greatest results.

For example, in the Central American hillsides in 1998 after Hurricane Mitch, researchers who surveyed farms and agricultural damage concluded that farmers engaged in diversification “such as cover crops, intercropping, and agroforestry suffered less damage than their conventional monoculture neighbors.”

These more-diverse farms, the researchers in the FAO report found, “had 20 to 40 percent more topsoil, greater soil moisture, and less erosion, and experienced lower economic losses” than those with more biodiverse farming systems after the hurricane.

In 2008, a similar study in Cuba after Hurricane Ike reported that diversified farms suffered significantly reduced losses: 50 percent of crop lost “compared to 90 or 100 percent in neighboring monocultures.” The researchers also reported that the more biodiverse farms recovered faster after the hurricane.

Evaluations in drought situations have also shown the benefits of biodiversity in farming. In Ethiopia, fields growing mixtures of maize cultivars performed better than monoculture fields, yielding 60-percent more crop in dry years. In Malawi, the soil of maize fields intercropped with legume trees held 50-percent more water in the weeks after rainfall.

According to FAO, the research has “bolstered a new recognition that biodiversity is integral to the maintenance of ecosystem functioning and points to the utility of crop diversification strategies used by traditional farmers as an important resilience strategy for agroecosystems.” IPES has similarly concluded that not only does diversity help reduce risks from seasonal shortages, but that it increases the “capacity to respond to extreme environmental shocks in ways that limit losses and enable recovery.”

Research conducted in the Pacific Islands by R.R. Thaman and colleagues found that diversity of crops within and between farms “gives a community insurance against natural disasters as different plants and different varieties of the same plants have differing susceptibilities to natural disasters and varying seasonalities which help to ensure than some food will be available after most disasters.” Research by Bioversity International, which conducts research on biodiversity in agricultural systems, similarly has found that  different species of crops grown by a farmer will react differently to various climate shocks.

Biodiversity at the farm level also has been found to increase soil quality. For example, in the same study of Hurricane Mitch, the farms practicing biodiversity had more top soil, more soil moisture, and less erosion compared to other farms.

Agroforestry, another farm-level approach to biodiversity involving growing trees and shrubs among crops, has also been used to promote more biodiversity. Agroforestry improves soil quality by providing additional organic matter, like leaves and mulch, to land while adding carbon to the soil. Trees also help reduce erosion in flood or storm events and help soil retain water by providing shade. Farmers with trees on their land, as the post-Hurricane Mitch research in climate change resilient farming shows, may have higher resilience to climate shocks than those without trees. The presence of trees also increases diversity of birds in ecosystems, which may reduce pest effects on crops.

These methods of increasing and supporting biodiversity are some of the most accessible ways for farmers to support resilience. Dr. Brenda Lin, a researcher of biodiversity and ecosystems in Australia, calls biodiversity a cost-effective and rational option for farmers of all sizes and in all regions, since farmers can tailor their approaches. Lin points out that biodiversity is applicable even for the world’s poorest food-producing households, which “tend to live in areas with degraded land, highly variable weather, and frequent weather shocks.”

Until now, Lin says, “economic incentives [have encouraged] production of a select few crops, the push for biotechnology strategies, and the belief that monocultures are more productive than diversified systems.” She says this has translated to slow adoption of practices for agricultural biodiversity. Now, though, experts such as Olivier De Schutter and Emile Frison of IPES are saying biodiversity for resilience-building deserves urgent attention.

According to FAO Director-General José Graziano da Silva, 2.5 billion people worldwide have agriculture-dependent livelihoods and are responsible for more than half of global agricultural production. Efforts from international agencies and private entities in the wake of recent climate disasters are focused on simultaneous recovery and resilience building. At a recent roundtable meeting after the devastating 2017 hurricane season in the Caribbean, World Bank President Jim Kim said, “the challenges faced by these small islands are a stark reminder that building resilience is not optional anymore.”

FAO has developed a Disaster Risk Reduction strategy for resilience building in vulnerable communities to address the need “to protect livelihoods from shocks, and to make food production systems more resilient and more capable of absorbing the impact of, and recovering from, disruptive events and to secure sustainable development gains.” In Laos, for example, villagers in one flood-prone region are broadening their livelihood diversity by varying the types of crops and livestock they raise. Agricultural biodiversity is part of the Sustainable Development Agenda: Sustainable Development Goal 2 involves preserving and utilizing genetic diversity of seeds, plants, and animals.

The Crop Trust’s Marie Haga told Food Tank that loss of agricultural diversity must be stopped and the genetic resources we have used in order to “achieve more resilience in our food systems and enable them to better withstand near-term shocks.” The Crop Trust runs the Svalbard Global Seed Vault, the world’s largest backup collection of seeds of all the world’s important crop varieties.


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