Nitrogen Loss Comparison in Surface Runoff vs. Tile Flow in Wisconsin Tiled Landscapes

Eric CooleyResearch Coordinator UW Discovery Farms

What Are Discovery Farms?

The Discovery Farms Program will develop on-farm and related research to determine the economic and environmental effectsof Best Management Practices on a diverse group of Wisconsin farms;

Discovery Farms Tile Research

A - Kewaunee County Two tile line sites

(2004 – 2009)

B - Manitowoc County Two tile line sites

(2004 – 2007, 2007 – 2011)

C - Waukesha County Two tile line sites

(2004 – 2009)

Tile line water monitoring

Tile line water monitoring

Surface runoff monitoring

Monitoring equipment

Surface and Tile Runoff Under Snowmelt Conditions

Tile flow began before surface flow

Relative volumes of water flowing in surface and tile were similar for this snowmelt period

Surface Water and Tile RunoffSnowmelt 2005

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4/1/05

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char

ge, c

ubic

feet

per

seco

nd

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Air

Tem

pera

ture

, Deg

rees

F

Surface-Water FlowTile FlowAir Temperature

Tile flow periods

Efficiency of tile water removal

Water Budget

Percentage of total precipitation leaving the landscape as surface water

Farm A Farm B Farm CSurface runoff 10% 6% 9%

Tile flow 24% 16% 16%

Surface & tile nitrogen loss

Surface & tile loss timing

Frozen Non-frozen Frozen Non-frozenFarm A 57% 43% 52% 48%Farm B 42% 58% 46% 54%Farm C 16% 84% 24% 76%

Total NitrogenTileSurface

Surface & tile loss speciation

Nitrate Ammonium Organic Nitrate Ammonium OrganicFarm A 45% 18% 37% 93% 2% 5%Farm B 20% 38% 41% 50% 18% 32%Farm C 22% 17% 61% 94% 1% 5%

Nitrogen SpeciationSurface Tile

The “Perfect Storm” tile nitrogen losses

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1500.0

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Dec-04 Mar-05 Jun-05 Sep-05 Dec-05 Mar-06 Jun-06

App

lied

Nitr

ogen

(lbs

/acr

e)

Tile

flow

(inc

hes)

Tile flow events, nitrogen applications and cropping history

Applied Nitrogen

Runoff Events

Alfa

lfa c

hem

ical

ly k

illed

10/

25/0

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Sand

man

ure

surf

ace

Sand

man

ure

surf

ace

Solid

sta

rter

w/ p

lant

ing

Liqu

id s

tart

er s

ide

dres

s

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id m

anur

e in

ject

ed

Rain on frozen ground Draught w/ yield reductions Warm, wet fall

Cor

n pl

ante

d

Cor

n si

lage

har

vest

ed

Cor

n pl

ante

d

Cor

n re

-pla

nted

Wet spring

The “Perfect Storm” tile nitrogen losses

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Dec-04 Mar-05 Jun-05 Sep-05 Dec-05 Mar-06 Jun-06

Con

stitu

ent C

once

ntra

tion

(mg/

L)

Tile nitrogen concentrations in various forms

Total N

Nitrate

Ammonium

Organic

The “Perfect Storm” tile nitrogen losses

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1600

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Dec-04 Mar-05 Jun-05 Sep-05 Dec-05 Mar-06 Jun-06

App

lied

Nitr

ogen

(lbs

/acr

e)

Con

stitu

ent Y

ield

(lbs

/acr

e)

Tile nitrogen yield in various forms

Applied NitrogenTotal NNitrateAmmoniumOrganic Nitrogen

Alfa

lfa c

hem

ical

ly k

illed

10/

25/0

4

Sand

man

ure

surf

ace

Sand

man

ure

surf

ace

Solid

sta

rter

w/ p

lant

ing

Liqu

id s

tart

er s

ide

dres

s

Liqu

id m

anur

e in

ject

ed

Rain on frozen ground Draught w/ yield reductions Warm, wet fall Wet spring

The “Perfect Storm” tile nitrogen losses

Tile SurfaceTotal (lbs/acre) WY05 WY06 WY07 WY05 WY06 WY07Total Nitrogen 14.6 99.0 35.0 19.5 10.7 3.7Nitrate 3.2 95.1 34.0 0.2 4.3 2.3Ammonium 7.1 0.4

Environmental Risks of Tiles- Macropores -

Preferential flow

Earthworm burrows

Root channels

Shrinkage cracks

Structural porosity

Dyed Burrows

Dyed Burrow

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1 -

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3 -

Credit: John Panuska

Soil drying and crack formation

Consistency of manure: 0-2% solids: high risk 2-5% solids: moderate risk > 5% solids: low risk

Application rate Tillage / manure incorporation Soil moisture content / tiles flowing Frozen soils

Factors Influencing Manure Contamination of Tile Lines

Tile drains can flow up to 365 days a year, even during frozen ground conditions

Tile drainage can deliver the majority of water and total nitrogen leaving agricultural fields

Good manure and fertilizer management is critical to reduce the loss of nutrients in tile drained landscapes

Take home points

www.uwdiscoveryfarms.org