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A review of two mandatory and two voluntary nutrient management strategies is …

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- Evaluating Livestock System Environmental Performance with Whole-Farm Nutrient Balance


Table 1. The nutrient management plan (NMP) must address the following nine elements to comply with the National Pollutant Discharge Elimination System (NPDES) permit requirements of the concentrated animal feeding operation (CAFO) regulations (USEPA, 2003).


Required NMP elements

Facility design and management Ensure adequate storage of manure, litter, and process wastewater, including adequate operation and
  maintenance capability.
  Ensure proper management of animal mortalities by avoiding disposal in manure storage or treatment systems.
  Ensure that clean water is diverted from the production area.
  Prevent direct contact of confined animals with waters of the United States.
  Ensure that chemicals handled on-site are not disposed of in any manure storage and treatment system.
Land application Identify appropriate site-specific conservation practices to be implemented to control runoff of pollutants to
  waters of the United States.
  Identify protocols for appropriate testing of manure, litter, process wastewater, and soil.
  Establish protocols to land-apply manure in accordance with site-specific nutrient management practices.

Identify specific records that will be maintained to document the implementation and management of the
  minimum elements described above.



Table 2. Summary of characteristics for the beef cattle feedlot used in case-study problem.{dagger}



Feedlot performance indicators

Location      Pierce, NE      
Head      2500      
Average turns per year      2      
Average daily gain, kg d–1      1.8      
Feed/gain, kg feed kg–1 gain      6.5      
Weight gain of cattle, kg      295–590      
Ration information


Feeding program{ddagger}

Feeding program, Option 1{ddagger}

  CP P Fed Purchased Fed Purchased
  % of dry matter

  Mg yr–1

  Mg yr–1

      kg animal–1 d–1     kg animal–1 d–1    
Feed intake     11.8     11.8    
CP, % of dry matter       13.6%     13.0%  
P, % of dry matter       0.51%     0.27%  
Corn  9.8 0.31  6.6 5430 4630  9.0 7410 6600
Molasses  8.5 0.03        0.6 220  220
Alfalfa 19.0 0.24  0.8 660  130  1.6 1320  780
Supplement 50.0 0        0.6 470  470
Supplement, no urea 0 0  0.6 470  470      
Corn gluten feed 21 1.00  3.8 3150 3150      
Soil test results and fertilizer use

  Field 1: Pivot Field 2: Feedlot quarter Field 3: Dry quarter
Crop grown and land area pivot: 49 ha continuous corn; corners:
  12 ha alfalfa
37 ha of alfalfa 52 ha in corn–soybean rotation
Five-year yield average, kg ha–1 10700 and 6700 11200 6300 (corn), 2800 (soybean)
University of Nebraska N
pivot: 170 kg N ha–1§; corners: – 45 kg ha–1 for corn
University of Nebraska P2O5
pivot: 45 kg ha–1 broadcast or 22 kg ha–1
  as starter; corners: 34 kg ha–1
0 kg ha–1 broadcast
Fertilizer application history pivot: 170 kg of anhydrous ammonia
  and 90 kg of MAP ha–1; corners:
  67 kg of MAP ha–1
none 67 kg of anhydrous ammonia ha–1
Harvest Manure is harvested typically after each turn of cattle and stockpiled until land-applied.
Application of manure solids It is typically surface-applied on alfalfa (feedlot quarter) in summer after second cutting and on row crops in February
  and not incorporated.
Application of open lot runoff

Open lot runoff water is collected for a 12-ha drainage area and land-applied through a big traveling gun, typically just
  before spring green up on alfalfa and after the third cutting in August.

{dagger} The farm participated in a survey of 33 farms from which data was collected for the purpose of estimating a whole-farm nutrient balance for each farm (Koelsch and Lesoing, 1999). To protect the identity of the farm, the case-study farm used in this discussion is shown on a site (Fig. 2) different from the farm's actual site but with a comparable land base and production potential.

{ddagger} Feeding program represents actual farm feeding program at the time of the survey and Option 1 represents a standard feeding program option without the corn gluten feed designed to provide similar energy and protein levels. Purchased feeds are for year in which corn is grown on dry quarter. Values are on a dry-matter basis.

§ Irrigation nitrate credit is not included.

Monoammonium phosphate (11–52–0).


Table 3. Effect of alternative best management practices (BMPs) on whole-farm phosphorus balance for beef case-study farm.


Balance 1: initial farm
balance, no BMPs{dagger}

Balance 2: nutrient
management plan (NMP)
implemented on land
managed by feedlot{ddagger}

Balance 3: NMP +
setbacks from water

Balance 4: 50% of
manure transferred to
off-farm users +
previous BMPs§

Balance 5: feeding
program Option 1 +
NMP and setbacks
(no corn gluten
feed used)

Animals, kg P yr–1 10800 10800 10800 10800 10800
Feed, kg P yr–1 46300 46300 46300 46300 24500
Fertilizer, kg P yr–1 2400 0 400 400 400
Managed outputs
Animals, kg P yr–1 19200 19200 19200 19200 19200
Crops, kg P yr–1 0 0 0 0 0
Manure, kg P yr–1 0 0 0 18100 0
Imbalance (or surplus)
P, kg P yr–1 40400 37900 38300 20200 16500
P, kg P ha–1 yr–1 270 250 260 130 110
Ratio of inputs to outputs






{dagger} Original farm balance is based on the farm characteristics described in Table 2 and Fig. 2.

{ddagger} These options assume the base feeding program (see Table 2) and modifications to crop nutrient management program to apply manure on an N basis (Balance 2) and addition of 30.5 m manure application setback (Balance 3), minimum requirements of the USEPA CAFO regulations.

§ This option assumes the same situation as Balance 3 (base feeding program, N-based NMP, and setback) plus the export of 50% of manure production to off-farm uses.

This option assumes the same situation as Balance 3 (base feeding program, N-based NMP, and setback) plus the implementation of feeding program Option 1 (see Table 2).


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