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Pulses provide environmentally sustainable source of nutrients‐rich food for humans and animals, as summarized in Figure 1.7 (GAP.org 2016). Sustainability of agricultural systems embrace long‐term environmental consequences that transcend short‐term productivity and efficiency objectives. A truly broad‐based construct associated of sustainability promotes the integration of food production practices and social needs. Thus, globally, agriculture sustainability must be considered as a social process besides technological practices and innovations. The production of legumes (dry beans and other pulses) has a rich and diverse history and serves as a global food resource within both industrially developed nations and indigenous populations. Since producing plant‐based foods are by far more environmentally conservative than the animal‐based ones (Gogoi et al. 2018), legumes will continue to play an increasingly major role to meet human food needs. Several elements of agricultural sustainability are clear or inherent in the production of pulses due to the considerably high total calorie and protein contents derived per unit of energy input:

Fig. 1.7. Pulses as environmentally sustainable food source for healthy people and healthy animals.

Source: Adapted from GAP.org (2016).

 Nitrogen fixing. Legume crops are distinguished by their unique ability to “fix nitrogen” and thus have significant impact on their need for soil‐borne nitrogen (Liu et al. 2011). By contrast, typically, major crops such as corn, wheat, and rice require added nitrogen to be productive and yield sufficiently to be economically viable. A progressive crop rotation is essential to maintain vital soil health and for managing weeds and disease pressure. Growers are generally diversified among several crops (e.g., corn, wheat, soybeans) – they are not exclusively dry bean producers on their farm acreage. Therefore, most fields are used for dry beans or other pulses every 3–5 years depending on the prescribed rotation. Not only do pulses directly benefit from the root‐nodulation encapsulated symbiotic bacteria, rhizobia, that generate soil nitrogen, but there is significant carryover nitrogen levels that benefit the subsequent rotation crop.

 Drought tolerance. Dry beans and other pulses are much more drought tolerant (GAP.org 2021) than many other major crops, particularly cereal crops. Dry beans require less total water and significantly less irrigation than alternative crops since arid and semi‐arid lands require the use of supplemental water to sustain plant growth (Ye et al. 2018). Dry beans require differential levels of water during various stages of growth, which is precisely determined and controlled. Moreover, dry beans and other pulses will reproduce seed under the most drought stressed conditions where the cereal grains will fail to reproduce.

 Field drying. Legumes are efficient at harvest because they require no or very limited external/additional seed drying as is common with corn, wheat, rice, and other cereal grains. Beans and other pulses are naturally dried to a moisture content of around 18% prior to harvest. By contrast, typically, corn and cereal grains require artificial, forced air drying, which requires huge fossil fuel (propane) energy input to reduce moisture content suitable for stable storage without mold/bacterial development and spoilage.

 Harvesting efficiency. Dry beans are increasingly produced from plants possessing an upright architecture that allows for more rapid drying and direct cutting with mechanized combines rather than traditional pulling of the plants and windrowing for air drying. This energy‐efficient innovation reduces overall fuel consumption compared to traditional harvest systems and avoids multiple field passes, which compact soil thereby requiring additional energy input for tillage.

 Biodiversity and productivity. Legumes are a world resource of biodiversity, providing significant land races of dry bean types providing genetic diversity within wide ranges of populations (Yang et al. 2021). The cultural practices associated with dry bean production, procurement, and preparation are very efficient. Additionally, research continues to enhance the productivity and efficiency of dry beans and other pulse crops that use reduced energy and agricultural inputs.