Spring 2006

Adapting a CAFOs NMP for Today’s Nutrient Challenges


By Rick Koelsch, University of Nebraska

The principles for Comprehensive Nutrient Management Plans (CNMP) were first released almost six years ago. The framework for a National Pollutant Discharge Elimination System (NPDES) Nutrient Management Plan (NMP) was released three years ago. Our understanding of the nutrient related issues has expanded during that time. However, are CNMPs and NMPs adapting to our new knowledge?

Some changes in our understanding of these issues include:

  • USDA ERS studies have suggested that most CAFOs have insufficient land for managing nitrogen and practically all CAFOs are short of land for managing phosphorus. This suggests that management plans based upon recycling manure more efficiently within the boundaries of the farm’s property may be only a partial solution. 
  • Feed is the primary source of nitrogen and phosphorus entering most CAFOs. Commercial fertilizer is often a distant second (see Figure 1).  Our cropping systems targeted nutrient plans have no impact on feed inputs. Are our nutrient plans ignoring the “800 pound gorilla” on our animal feeding operations?
  • The degree to which best management practices are implemented gives us little insight into the nutrient performance or efficiency of individual CAFOs. Our nutrient plans typically provide little insight as a “yardstick” for measuring nutrient performance.
  • EPA has the power to regulate ammonia emissions from livestock operations. In addition, ammonia volatilization may not be the benign nutrient loss we have historically assumed it to be.

Figure 1. Source of phosphorus inputs to 33 Nebraska confined swine and beef cattle operations.Do our CNMPs and NMPs need to adapt to our changing knowledge of nutrient issues? Our current public policy targets efficient recycling of manure nutrient’s within the boundaries of the CAFO’s property. While this approach is a first step toward achieving animal feeding operations that are sustainable, it may not be the final solution for most CAFOs.

An open discussion is needed to identify how our planning processes must evolve to solve the nutrient challenges on livestock and poultry operations. I propose that the following potential changes should be a part of that discussion:

  • Should a nutrient plan include an estimate of a farm’s ammonia emissions?  Rates above 100 lbs per day are reported by most industries to EPA. A nutrient plan that provides an estimate of ammonia emissions would be an important first step to creating an awareness of the animal industry’s ammonia emissions.
  • Should a nutrient plan estimate the quantity of excess manure nutrients that can not be managed within the boundaries of the CAFO?  We must recognize that animal feeding operations that purchase significant quantities of their feed from off-farm sources must also export significant quantities of manure. A nutrient plan that estimates the magnitude of those excess manure nutrients is an important initial step toward sustainability.
  • Should a nutrient plan include an animal nutritionist’s review of the potential for reducing feed nutrient purchases?  The CNMP has included a feed management component but it has been largely ignored and little or no effort made to involve professionals competent in animal nutrition.
  • Should a nutrient plan include a calculation of the dollar value of manure and/or a manure marketing plan? If we want to change manure management practices, demonstrating an economic value is a much more powerful message than demonstrating an environmental value. Our manure marketing workshops this past summer consistently demonstrated manure values in excess of a $100 per acre for feedlot manure. A nutrient plan that demonstrates the dollar value of manure may be more readily implemented.
  • Should a nutrient plan include an expectation for documenting environmental performance?  Over the years, many have made excuses as to why it can’t be done.  But we have never invested similar energy in how it might be done.  I believe it is time to have the later discussion.
At the Heartland Water Quality Conference for extension educators, we heard about an Iowa watershed that bases incentive payments on common field measurements of performance (P Index and stalk nitrate tests). These measures provide one example for measuring “individual field” nutrient performance.

Figure 2. Whole farm nutrient balance (ratio of inputs to managed outputs) for 33 Nebraska swine and beef facilities.The Dutch have used the MINAS (mineral accounting system) for measuring farm level inputs and outputs to measure “whole farm” nutrient performance since the early 1990’s. An evaluation of this approach with 33 Nebraska farmers in 1997 provided a very clear differentiation between those farms achieving nutrient sustainability and those with significant challenges (Figure 2). There is no doubt that we have the tools and capability to measure performance today. The doubt that remains might be related to our desire to know the answer.

Our understanding of nutrient issues for animal feeding operations is changing. Our nutrient planning processes must adapt to emerging nutrient issues and to our improved understanding of the underlying causes of nutrient accumulations and losses from some animal feeding operations. Future nutrient planning processes may need to recognize the critical role of feed nutrient inputs, the situations when manure nutrients must be exported, the emerging importance of ammonia-N emissions management, and the value of measuring nutrient performance. Our integration of these topics into nutrient plans will make a critical contribution to improving environmental stewardship in animal agriculture.

This article first appeared in the Heartland Regional Water Initiative Coordination Newsletter and is reprinted with permission of the author.


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