UN celebrates World Soil Day by emphasising role of pulses to boost sustainable agriculture

New report explores how nitrogen-fixing plants enhance nutritious diets, carbon sequestration and soil fertility
New report explores how nitrogen-fixing plants enhance nutritious diets, carbon sequestration and soil fertility

Soil and pulses can make 'major contributions' to the challenge of feeding the world's growing population and combating climate change, according a new report by the UN Food and Agriculture Organization (FAO) released today on World Soil Day (5 December).

The report, titled 'Soils and Pulses: Symbiosis for Life' stated: "Soils and pulses embody a unique symbiosis that protects the environment, enhances productivity, contributes to adapting to climate change and provides fundamental nutrients to the soil and subsequent crops."

Pulses are environmentally resilient crops that deliver high-nutrition foods to people and critical nutrients to biological ecosystems. Soil, a non-renewable resource, is essential for plant life and 95% of the global food supply.

The report illustrates a variety of ways that pulses and soils can be "strategic allies" in forging more sustainable food and agriculture systems
The report illustrates a variety of ways that pulses and soils can be "strategic allies" in forging more sustainable food and agriculture systems

Pulses such as lentils, dry beans and chickpeas are nitrogen-fixing plants that can benefit soil health, leading to better growing conditions for themselves and for other plants. On average, cereals grown after pulses yield 1.5 tonnes more per hectare than those not preceded by pulses, which is equal to the effect of 100 kilograms of nitrogen fertilizer.

The report illustrates a variety of ways that pulses and soils can be "strategic allies" in forging more sustainable food and agriculture systems.

Earlier today, FAO's Council - representing the Organization's member states - endorsed the Voluntary Guidelines for Sustainable Soil Management, a set of technical and policy recommendations on protecting the world's largest terrestrial pool of carbon. These guidelines - to be implemented at all levels - constitute the main tool to foster sustainable soil management and boost soil health.

Pulses on the farm

One-third of the world's soils are now deemed degraded, due to a range of causes including acidification, salinization, erosion and urbanization, a matter of growing concern due to the intricate range of life-supporting ecosystem services they provide.

Introducing pulses as part of intercropping, cover crops and crop rotation farming techniques can help restore soil health. Legumes, the plant family of which pulses are a part, can grow with fewer nutrients than many others, while providing nitrogen, soluble phosphates and other needed compounds to soils.

"Pulses are architects of soil health," according to the report. They host special soil bacteria enabling the biological fixation of nitrogen, a natural process that would cost an additional $10 billion a year in synthetic fertilizers. They also foster soil carbon sequestration and cleaner water filtration.

The world is currently losing soil 10 to 20 times faster than it is replenishing it, a trend pulses can help offset. The report cites a case study in India showing how growing pigeon peas reduced soil runoff and erosion by up to 59%.

Moreover, pulses - whose deep root systems boost their resilience in drought - are intrinsically "climate smart as they simultaneously adapt to climate change and contribute towards mitigating its effects" by boosting soil carbon sequestration capacities.

In the vast western wheat fields of Canada, one of the world's greatest pulse producer and leading exporter, the introduction of pulses into field rotation has trimmed the need for synthetic nitrogen by two-thirds, underscoring the substantial role pulses can play in lowering global greenhouse gas emissions.