Managing Manure Application for Reduced Phosphorus Runoff Loss

1
Managing Manure Application for Reduced
Phosphorus Runoff Loss

• Charles Wortmann
• Department of Agronomy and Horticulture

2
Topics

• Results from a runoff study at the ARDC, 1998 to
  present
• CSREES Managed Ecosystems project on P management
  in the corn-ethanol-beef ecosystem

3
The Effect of Composted Manure Application and
Plowing on Phosphorus Runoff

• Charles Wortmann and Dan Walters

4
Phosphorus in fresh surface waters

• P is often most limiting nutrient to the growth
  of aquatic vegetation
• Agricultural land is a major source of P
• Greater losses with high soil test P, e.g. where
  much manure has been applied
• Manure P excretion is increasing as diet P
  increases due to feeding by-products

5
Research at the UNL ARDC 1998 - 2007
6
Manure P Runoff Study, UNL ARDC silt loam soil,
5.5 slope, 7 treatments, 3 replications
7
Plot size 40 m2
8
(No Transcript)
9
(No Transcript)
10
Objective Determine the effects of compost
application practices on runoff, sediment loss,
and P loss

• During the years of application, 1998-2000
• The residual effects during 2001 to 2004
• Residual effects during 2004 to 05 and effect of
  plowing extremely high P soil
• Residual effects of 2006-07 and effects of
  vegetative barriers

11
Methods

• Composted feedlot manure was applied annually for
  3 years to meet the N need of irrigated corn
• Why not raw manure?
• Two compost types were used
• Low P compost 670 lb/A P applied
• High P compost 1025 lb/A P applied
• The plots were disked

12
Compost effect on soil test P (Bray-P1) in March
2004
13
Results Runoff and erosion, 98-00

• greatly reduced by compost application during
  the years of application.

14
Runoff and erosion 01-04

• reduced by the residual effect of compost
  applied 1-4 yr previously.

15
Runoff and erosion 04-05

• The residual effect of compost at 4 5 yr after
  application
• Slightly reduced runoff
• Greatly reduced erosion
• The effect of plowing
• Reduced runoff
• Slight increase in sediment loss

16
P loss during years of application 99-01

• Compost application
• P concentration in runoff much higher.
• P loss was increased.

17
01-04. Runoff P concentrations were very high 1-3
yr following compost application.
18
Runoff P loss was greater with compost applied,
but not so much given the difference in soil test
P.
19
Nov. 2005

• Soil P levels remained very high where compost
  had been applied 4 years before
• Plowing greatly reduced P at the soil surface.

20
2004-05 P loss

• The residual effect of compost at 4 5 yr after
  application
• Much more dissolved P loss
• About 100 more total P loss
• The effect of plowing
• Greatly reduced dissolved and total P loss

21
Phase IV, 2006-2007

• Continued study of residual effects
• Vegetative filter strips occupying 1 or 4 of the
  plot area

22
Summary

• Effects of composted manure application during
  the application years, and for 5 years after,
  include
• Greatly increased soil test P
• Reduced volume of runoff and erosion
• Increased runoff P concentration and loss

23
Summary

• Runoff P loss was more affected by change in
  erosion and runoff rates compared to soil test P
• Excessive amounts of P can be applied with little
  loss if there is little erosion and runoff.

24
Summary

• Plowing soil with excessively high surface P
  reduced
• runoff with no increase in erosion
• runoff P concentration, and
• runoff P loss.
• However, erosion needs to be prevented.
• Well-placed vegetative filter strips occupying 1
  of the land area are reducing runoff and P loss

25
More information

• Wortmann and Walters, 2006. Phosphorus runoff
  during four years following composted manure
  application. J. Environ. Qual. 35 651-657.
• Wortmann, C.S. and D.T. Walters. 2007. Residual
  Effects of Compost and Plowing on Phosphorus and
  Sediment in Runoff. J. Envir. Qual. Under review.

26
Manure use and soil aggregate stability percent
of soil in water stable aggregates at 30 DAA
27
Manure use Bray-P1 in soil aggregates at 30 DAA
28
(No Transcript)
29
Reducing Risk of Phosphorus Pollution of Surface
Waters in Crop-Ethanol-Livestock Ecosystems of
the MidwestC. Wortmann, C. Shapiro, D.
Tarkalson Agronomy HorticultureH. Nourdenni
Chemical Engineering G. Erickson Animal
ScienceT. Franti, D. Schulte Biological Systems
EngineeringD. Jose Agricultural EconomicsK.
Brunkhorst Nebr. Corn Board USDA-CSRESS
Managed Ecosystems/Nebraska Corn Board
30
(No Transcript)
31
Image from Dan Otto et al. ISU

• Each bushel of corn yields approximately
• 1/3 EtOH
• 1/3 CO2
• 1/3 Distillers byproducts

32
Image from Dan Otto et al. ISU
33
Corn
Beef
Ethanol
34
Ethanol Plants Fed Cattle Population (Erickson
and Koelsch)
35
Utilization efficiency of co-products by beef
cattle (from Erickson and Klopfenstein)
Vander Pol et al., 2006 Nebraska Beef Rep. and
2005 Midwest ASAS
36
Feeding co-products P intake and excretion by
beef cattle (Erickson Koelsch)
Dietary P effect on manure
Kissinger et al., 2006 NE Beef Report
37
P reduction project, Oct. 05 - 09 feeding beef a
ration of 40 bi-products results in 100 more P
excretion (and gt75 more NH3 volatilization)
Ethanol co-products
38
P removal from ethanol stream
39
(No Transcript)
40
Composting vs. stock-piling feedlot manure

• Development of decision guide
• To evaluate the economics of composting vs.
  stockpiling
• Research on N loss with composting

41
Research at the UNL ARDC 2005 - 2007
42
Setback distance .

• Effect of non-application (setback) distance to
  concentrated water flow.

43
Watersheds GIS and stakeholders
Link spatial modeling results with local knowledge

• Develop criteria for targeting of P BMPs in
  landscapes
• GIS linked with simple tools (e.g. RUSLE1,
  modified P index) for field-level use by
  stakeholder groups

44
Heartland .
45
Thank you! Questions?