By Philip Newell
According to a recent New York Times article, an increase in temperature due to climate change will likely decrease yields of current crop varieties in the United States by 30 percent. The article also points out that there is some good news- by developing heartier, more tolerant crops now, we can adapt to changes in climate.
While climate change will not be stopped by a handful of crops, these plants present significant potential. If they are cultivated more widely and endorsed by farmers, agricultural development agencies, and the funding and donor community, they can be a key component to the global mitigation of climate change.
Today, Nourishing the Planet introduces five plants that you have likely never heard of that are helping create resilience to climate change.
The Marula Tree can be processed into a variety of goods, and provides fertile habitat for growing additional crops! (Photo credit: Marula natural products)
1. Cowpea: Grown in Africa for generations, the cowpea is one of the most ancient crops on the continent. This perseverance is partly because of its ability to survive harsh weather and drought conditions. The black-eyed pea, as it is known to Americans, is a very healthy food, allowing the body to absorb even more nutrients from other grains such as rice or sorghum. This legume is not only good for human health; but it can actually improve the health of the field in which it grows. Legumes are a type of plant that (among other things) acts as a nitrogen-fixer. This means that when grown, legumes, like the cowpea, absorb nitrogen from the air and deposit it into the soil. The next crop grown on that land then benefits from the increased levels of nitrogen in the soil. This can allow farmers to skip the application of expensive chemical fertilizers. Even among legumes the cowpea is a hero, due to its long roots. These tap roots reach way down into the soil, helping provide moisture accessible to the cowpea and future crops. And cowpeas’ stems and leaves are good fodder for livestock.
Cowpea in action: In October 2010, the International Institute for Tropical Agriculture hosted the 5th annual World Cowpea Research Conference. Topics for the conference included genetic improvement, grain and seed storage improvement, cropping systems, and many others. Researchers are hoping to find ways to develop more nutritious varieties of cowpeas for human consumption, as well as varieties that are insect resistant and others that are better suited for use as cover crops, livestock feed, and even growing in space.
2. Marula: The Marula tree can help regenerate forests and declining bee populations, which is helping to address deforestation and desertification, while also producing nectar. This nectar production makes it a favorite among bees, whose habitats face destruction by human activity such as conventional agriculture and urbanization. Tolerant of hot, dry climates and saline water, the Marula tree grows well even during times of drought-fortunate considering the chaotic effect of climate change. The restorative qualities of this tree are one crucial ingredient in ending the cycle of deforestation by regenerating degraded landscapes. In addition to all of this, the tree produces a delicious fruit with a nutritious nut at its core.
Marula in action: South Africa is a significant producer of marula, using it for a variety of goods, such as cosmetics from its oil, and it is also used as a prime ingredient in Marula beer or South Africa’s Amarula Cream liquor.
3. Locust bean: Capable of acting as the first step in reforestation, the Locust bean is another tree with huge potential. This tree is extremely hardy, capable of thriving in many different soil types. It produces a sugary fruit and the pulp is prized for its sweetness. Because it is a tree, its woody trunk and branches sequester CO2 for as long as the tree lives. This effect, multiplied by thousands of trees, can serve as a significant sink for global carbon emissions. But that’s not all! It also has nutrient-rich leaves that can be harvested and used as fertilizer, replacing other chemical inputs. This nutrient availability decreases the amount of chemical fertilizers that need to be produced, purchased, transferred and applied.
Locust bean in action: In Western Africa, women process the seed of the tree into an extract, which is then sold on the market. The product, known as dawadawa, is an important flavoring ingredient to traditional soups.
4. Marama: One crop capable of slowing the progress of desertification while providing nutrition is the marama. These tubers are highly drought-tolerant, and what water they do receive is efficiently stored in its giant root, which can grow up to 200kg! Water is not its only product, as the marama is also being investigated for its ability to produce oil. The oil produced can potentially be converted into the type of vegetable oil used to power combustion engines. The marama spreads widely and quickly across dry soils, providing biomass that prevents the continued loss of nutrients and solids that create deserts. Dry, uncovered soil acts as a mirror, reflecting the Sun’s light and heat back into the atmosphere (known as albedo), where it is trapped by the greenhouse gasses responsible for climate change. By covering this ground with biomass, some of the light and heat are absorbed instead of reflected.
Marama in Action: The University of Copenhagen is undergoing research in Southern Africa on the capability of the marama to provide sustenance and livelihood for indigenous populations.
5. Birdsfoot trefoil: This leguminous cover crop is similar to alfalfa but better suited to poor growing conditions where soil is likely to be exposed. The plant is digested more efficiently by livestock than other grasses and conventional feed mixes. The efficient digestion means that they produce significantly lower levels of methane, a major GHG source. In addition, birdsfoot trefoil is a nitrogen-fixer, adding nitrogen to the soil and allowing farmers to use smaller quantities of artificial fertilizer.
Birdsfoot trefoil in action: The Union of Concerned Scientists reports that using birdsfoot trefoil as a cover crop and as a foraging crop for cows could reduce methane emissions significantly from current levels, without large additional costs. By replacing traditionally grown alfalfa with this legume, farmers and ranchers can improve their soil while reducing their emissions.
Philip Newell is a research intern with Nourishing the Planet.
To read more about how these plants are creating a more resilient world, see: The Little Legume that Could; Marula: Food, Function, and Sustainable Development; The Locust Bean: An Answer to Africa’s Greatest Needs in One Tree; The Green Gold of Africa; or Fighting Climate Change by Managing Livestock.