Sustainability Metrics Moving Forward on Large-Scale Farms

Paul Vincelli, Ph.D.

LEXINGTON, KENTUCKY

   Introduction

   I attended the recent Sustainable Agriculture Summit in Phoenix, Arizona.  This, my first time at this conference, turned out to be a highly enriching, “good news” experience.  

   There were many discussions and presentations on sustainability, what it means, and how to measure it.  This conference is a place where large-scale food producers, aggregators and input manufacturers have   a home among like-minded large-scale actors who share an interest in food-system sustainability.  There were frequent expressions of concern and interest among participants for not only cost, quality, and availability of food, but also for the place that food production and marketing have in creating a more sustainable world.   

   Examples

   One of the most striking things I observed was how much work was going on among large-scale food-system actors in measuring and analyzing quantifiable expressions of sustainability.  Philosophical discussions on sustainability were welcome, but even more welcome was detailed guidance on how to measure sustainability within real-world food systems.  Here are some examples of sustainability metrics used in real-world farms.

   Economic, Agronomic, and Animal Performance

• Measures of yield and profitability are nearly universal metrics that reflect goals of the farmer, and profitability is considered a fundamental pillar of sustainable agriculture.  

   Numerous metrics provide measures of resource-use efficiency. For example, metrics of irrigation efficiencymay be calculated in several ways.  One approach is to divide dry matter produced by the water utilized by the crop or commodity produced.  Feed efficiency provides information on the efficiency of conversion of feed to animal products.  Metrics of energy efficiency include BTU utilized per acre planted or per ton harvested.  Nitrogen use efficiency is calculated by dividing the amount of nitrogen added to the system by tons of product harvested.  Resource use efficiencies may mean more money in the farmer’s pocket (the profitability pillar), but more efficient use of resources may also result in less impact on the environment from farm production (the stewardship and social pillars).  

   Stewardship

   Sustainability metrics directed at environmental stewardship were commonly discussed or mentioned at the conference and in related sources. This may be because so many environmental metrics exist.  A few examples:

• Measures of greenhouse gas emissions are critically important metrics of the impact of agriculture on the environment, because of the importance and rapid pace of climate change.  These measures also are required for farmers to participate in carbon markets.
• Nitrogen balance is the difference between the nitrogen added to a field minus the amount removed at harvest.  That difference provides an estimate of the potential amount of nitrogen that may move off-site, potentially contributing to air pollution and water pollution.

• Phosphorus metrics may include subtracting the amount P applied minus the amount recommended, providing an estimate of excess phosphorous applied.
  
  
• Social

• Social considerations regarding food production collectively represent a fundamental pillar of sustainability (https://www.sare.org/).  Metrics on employee safety and well-being (such as safety training rates and safety incident rates) can help farmers implement and evaluate employee safety programs.  Indeed, highly ambitious worker safety programs may set safety incident standards as low as zero safety incidents.   Such metrics help farmers monitor their safety plans.  They also help create a work culture supportive of worker protection.

• Metrics relating to animal care can help evaluate progress in the application of industry standards of animal health and well-being.  Examples include participation and completion of training programs or certification programs in animal care).

   Other

• “Soil health” is a complex topic.  Furthermore, the term has multiple meanings.   Consequently, a wide variety of metrics have been associated with it.  Examples include soil organic matter content, soil microbial respiration, available water capacity, aggregate stability, soil pH, soil protein, active carbon, and others. 
• Straight-forward metrics such as farm area cropped and percentage intercropped—can be assembled to provide sophisticated metrics for estimating on-farm biodiversity.  The fact that such metrics are being used by farmers is impressive and to the credit of the agricultural community.  Metrics of biodiversity are likely to only grow in sophistication and use.   

• Food loss refers to how much product is grown to the point of harvest but does not enter the food chain.  It can be measured at any step in the food chain.  Wasted food at any point in the food chain has an environmental impact with little to no human benefit.

   Motivations

   There are diverse reasons why producers and aggregators may collect and monitor sustainability metrics.  Consumers have a substantial impact on the market through their purchasing choices and, for many, sustainability is an important personal consideration. Likewise, many farmers consider sustainability metrics in making management decisions, particularly among those with a personal commitment to improving farm sustainability.  This was a common motivation among farmer-leaders I spoke to. Their commitment to a sustainability path seemed quite genuine.  Additionally, producers may be motivated to consider sustainability metrics based on compliance with regulations, to capitalize on incentives, for positive public perception and for marketing purposes.  Whatever the reason, the trend toward normalizing sustainability metrics is a good one. 

   Conclusion

   “Sustainability” is no longer a buzzword in farming.  It is a legitimate goal among farmer-leaders and food-system leaders, who “come to the table” with intelligence, ideas, and commitment.  Yes, serious and difficult challenges lie before us in helping to create more sustainable food systems.  However, this is an exciting time it is to be a farmer or to work with farmers, and to be part of this continuing evolution in food systems. ∆

   Paul Vincelli, Ph.D.: University of Kentucky and Southern SARE Program; Extension Professor and Provost’s Distinguished Service Professor; 1862 Liaison for Sustainable Agriculture Research and Education Program (SARE); Jefferson Science Fellow, Washington DC (2019-2020)