Rice-loving Filipinos can contribute to the reduction of greenhouse gas emissions by incorporating lentils, beans, chickpeas, and other pulses into their diets. This may sound like something out of Robert Ripley’s “Believe It or Not!”; however, it is indeed a reality.
Pulses are annual crops that produce between one and twelve seeds per grain. The designation “pulses” is specifically reserved for crops that are harvested exclusively as dry grains, distinguishing them from other vegetable crops that are picked while still green.
Pulses enjoy widespread popularity across the globe. In 2022, global pulse production reached approximately 96 million tons, with projections indicating an increase to 125 million tons by 2032.
Worldwide, around 190 million tons of pulses contribute between five and seven million tons of nitrogen to soils. According to the Rome-based United Nations Food and Agriculture Organization (FAO), pulses represent a food source with a low carbon footprint.
Pulses utilize soil bacteria to draw nitrogen from the air. This natural process replaces the need to add nitrogen fertilizers in pulse crops, which means pulses use half the energy inputs of other crops.
“When soil is fertilized with nitrogen in the form of manure, fertilizer, or crop residue,” a source explained, “soil micro-organisms convert some of this nitrogen into nitrous oxide, which is a powerful greenhouse gas.”
Nitrous oxide is 300 times more potent than carbon dioxide and represents around 46% of the greenhouse gas emissions from global agriculture, according to the United Nations Environment Program (UNEP).
“Since greenhouse gas emissions related to crop production are largely driven by nitrogen fertilizers, nitrogen-fixing pulse crops have a lower carbon footprint compared to other crops,” says the UN food agency.
Aside from fixing atmospheric nitrogen in the soil naturally, pulses also in some cases free soil-bound phosphorus, thus significantly decreasing the need for synthetic fertilizers, FAO says.
Another good thing about pulses: When included in livestock feed, their high protein content contributes to increase food conversion ratio while decreasing methane emissions from ruminants. As such, pulses again reduce greenhouse gas emissions.
Climate change, an environmental threat unlike any other the world has faced, is thought to be caused by an increase in the amount of greenhouse gases spewed into the atmosphere through human activities. Greenhouse gases refer to carbon dioxide, methane, nitrous oxide and other industrial gases.
Climate change has a huge impact on global food production and food security, the UN food agency states. “Changing weather patterns can cause an increase in natural disasters like droughts, floods, hurricanes, which can impact every level of food production,” FAO points out.
Unless urgent and sustainable measures are established, climate change will continue to put pressure on agricultural ecosystems, warns FAO while recommending to increase global pulses production by 20% from the current level by 2030.
FAO recognizes that pulses production has significantly lagged behind the rising demand in the developing world in spite of many benefits of pulses which are a “win-win for people and the environment – healthier soils, low carbon and water footprints, and greater household nutritional security, while also generating extra income for farmers.”
Pulse crops utilize soil moisture efficiently. “When pulses are grown, they use one-half to one-tenth the water of other sources of protein,” wrote A.Y. Hoekstra and A. Chapagain, authors of the book, “Globalization of Water: Sharing the Planet’s Freshwater Resources.” “Many pulse crops are adapted to dry environments, making them well-suited for areas that are prone to drought.”
That’s not all. According to the two authors, pulses extract water from a shallower depth, leaving more water deep in the soil for the following year’s crop. “This increases the water use efficiency of the entire crop rotation,” the authors pinpointed.
Another plus about pulses: they enrich the soil where they are grown. “Pulse crops produce a number of different compounds that feed soil microbes and benefit soil health,” the source said. “After pulse crops are harvested, they leave behind nitrogen-rich crop residues that provide extra nutrients for the next crop that is grown.”
This is the reason why some farmers use pulses in crop rotation. “Growing pulse crops in rotation with other crops enables the soil to support larger, more diverse populations of soil organisms that help maintain and increase soil fertility,” the source said.
Pulses have a long, rich history. The first evidence of pulses comes from 11,000 years ago in the Fertile Crescent, a region in the Middle East which was home to some of the earliest human civilizations.
FAO recognizes 11 types of pulses: dry beans, dry broad beans, dry peas, chickpeas, cow peas, pigeon peas, lentils. Bambara beans, vetches, lupins and pulses. Popular pulses include kidney beans, lima beans and butter beans. Soybean and peanuts are excluded because they are used mainly for oil extraction.
Perhaps not too many Filipinos know that pulses are very nutritious. “They are packed with nutrients and have a high protein content, making them an ideal source of protein particularly in regions where meat and dairy are not physically or economically accessible,” the FAO says.
Pulses are good for those who want to go on a diet or have diabetes. “Pulses are low in fat and rich in soluble fiber, which can lower cholesterol and help in the control of blood sugar,” the FAO claims. “Pulses have also been shown to help combat obesity.”
Aside from protein, pulses are also a good source of amino acids, fiber and essential nutrients like iron, potassium and folate.
Staple dishes and cuisines from across the world feature pulses, from hummus in the Mediterranean (chickpeas) to a traditional full English breakfast (baked navy beans) to Indian dal (peas or lentils).
