Sustainability

Pulse crops have one of the lowest carbon footprints of any crops out there, but did you know that pulses grown in Canada are especially sustainable?

Pulses have a naturally lower carbon footprint than most foods because they require little to no nitrogen fertilizer to grow. This is because they have a special relationship with certain soil bacteria that convert nitrogen from the air into a form that is usable to the growing pulse crop. Beyond that, Canadian farmers have adopted practices such as minimum tillage and reducing fallowing, which are practices that have been proven to sequester large amounts of atmospheric carbon into soils. This sequestration of soil carbon negates the carbon emissions of producing a pulse crop, creating a carbon-neutral or even a carbon-negative crop. This is why simple reformulations with pulse flours can have a major impact.

Organizations that haven’t already set sustainability goals will likely soon have to, if not to align with growing consumer demand, then to align with national goals and regulations set by their governments. Building a transparent sustainability claim should start with data points from the entire life cycle of the product. Data that considers a comprehensive view of environmental impacts throughout the value chain allows food manufacturers to confidently assess the impact of their products.

A good benchmark for data quality is a life cycle assessment (LCA). An LCA is a standardized method of quantifying environmental impact (e.g. greenhouse gas emissions, land and water use) across the entire life cycle. This is done by capturing all of the resource inputs needed to produce that product. In the case of crops like pulses, that means fertilizers, fuel, crop protection products and energy use.

Pulse Canada has LCA assessments for pea, lentil, faba and dry bean crops. The LCAs began with a survey of hundreds of producers in Alberta, Saskatchewan and Manitoba. The survey data was then reviewed by a number of experts from different fields including crop fertility, pest control, on-farm fuel and energy use, and general agronomy. The final data has been published on EcoInvent, one of the largest and most transparent life cycle inventory databases. This allows companies and researchers to access the raw Canadian data to conduct LCA’s on their own food and ingredients that include Canadian pulse ingredients.

Nitrogen Fixation

The production and use of nitrogen fertilizers are a significant contributor to the overall carbon footprint of agriculture and food production. Pulses like beans, peas and lentils have a naturally lower carbon footprint than most foods because they require little to no nitrogen fertilizer to grow. Pulses have a special relationship with certain soil bacteria that convert nitrogen from the air into a form that is usable to the growing pulse crop. This process is known as symbiotic nitrogen fixation.

Water Efficiency

Canadian pulses are resilient and require less water to grow. Pulses such as peas, lentils and chickpeas are well-adapted to semi-arid conditions and can tolerate drought stress. Pulse crops like peas and lentils also use water in a different way than other crops grown in rotation, extracting water from a shallower depth, leaving more water deep in the soil for the following year’s cereal or oilseed crop.

Soil Health & Crop Systems

Canadian pulses naturally revive depleted soil, and save on inputs. Pulses produce a number of different compounds that feed soil microbes and benefit soil health. A healthy and diverse microbial community is able to decompose and cycle nutrients more efficiently, feeding crops naturally as they grow. In addition, a large, diverse population of soil microorganisms acts to ‘crowd out’ disease-causing bacteria and fungi, making for healthier plants. Growing pulse crops in a rotation with other crops enables the soil environment to support these large, diverse populations of soil microorganisms.

Rotation Benefits

Including peas, lentils or beans in crop rotations also confers sustainability benefits for the crops grown after. Crops like wheat and barley produce higher yields and have higher protein when grown after pulses. This is due to the soil fertility, water and soil microbial benefits of pulse crops which also benefit the following crops. These benefits also reduce the carbon emissions of following crops due to a reduced need for fertilizer. One study has estimated that including pulses in a rotation with Canadian wheat contributed 1.3 MT of carbon emission savings, approximately 2% of the entire carbon footprint of Canadian agriculture.