Agricultural Nonpoint Source Pollution and Water Quality as afunction of Land Management Practices on Four Kansas Farms
William W. Spotts
Dr. Donald Huggins
Dr. Jerry DeNoyelles
Dr. Chip Taylor
Introduction
• Agricultural nonpoint source pollution
• Best management practices (BMPs)
• Research: sampling and modeling
Agricultural nonpoint source pollution (NPSP)
• The USEPA has identified agricultural NPSP as the major source of stream and lake contamination preventing attainment of the water quality goals identified in the Clean Water Act. (1988).
• What ? Nutrients, pesticides, sediment, pathogens
• Who? Livestock and cropping systems
• How ? Diffuse, episodic, weather-driven
• Where ? KDHE 97% of streams and 80% of lakes
• Why ? Impacts water quality, aquatic communities, reservoirs
Nonpoint source pollution: Cropland
• Tillage
• Field applications
Nonpoint source pollution: Livestock
• Erosion
• Fecal coliform
• N and P loading
Introduction
• Agricultural nonpoint source pollution
• Best management practices (BMPs)
• Research: sampling and modeling
Best Management Practices (BMPs)Methods, measures or practices designed to prevent or reduce pollution
• Structural controls
• Source controls
• Land management
How do you measure the “effectiveness” of BMPs?
Introduction
• Agricultural nonpoint source pollution
• Best management practices (BMPs)
• Research: monitoring and modeling
Research: monitoring and modeling
• Monitoring: Describe trends, evaluate effectiveness
• Modeling: Predict pollutant movement
• Goal: Provide reliable estimates of pollutant loads
• Application: Total Maximum Daily Load (TMDL)
Project overview
• Clean Water Farms Project
• Four farms with different land management practices
• Runoff and groundwater for 2-5 years
• SIMPLEX for comparisons
Important Questions• What are typical edge of field concentrations relative to
different land management practices ?
• What factors influence agricultural water quality?
• How do experimental values compare to the expected values?
• Can changes in land management lower nutrient and herbicide levels in groundwater and field runoff ?
Experimental methods
• Monitoring program design
• Sampling efforts
• SIMPLEX Loading Model
Aspects of a NPSP monitoring program
• Goals
• Management
• Opportunistic
• Adaptable
• Participation
Runoff sampling
• Sigma 800SL
• Edge of field data
• First flush runoff
Sampling Shallow Groundwater
• Lysimeter clustersDepth
• Transect approachSpace
Primary agricultural nonpoint source pollutants
• Nitrogen
• Phosphorus
• Atrazine
Modeling Runoff SIMPLEX Nutrient Loading Version 1.0
• Goal: Estimate runoff volumes• ArcView GIS
– Aerial Photos (DOQQ)
– Land Use / Land Cover (site visits)
– Drainage area (DRG)
– Soils (SSURGO)
• Inputs: Watershed area, LU/LC and precipitation
DOQQ and LU/LC
Add Topography…
To define the contributing drainage area
LU/LC, Drainage and Soils
Runoff volume and loading estimator
On-farm research of agricultural NPSP
Kansas EcoregionsCentral Great PlainsCentral Irregular PlainsCentral Oklahoma/Texas PlainsFlint HillsOzark HighlandsSouthwestern TablelandsWestern Corn Belt PlainsWestern High Plains
Monitoring crop production systems
• Land management practices– Stripped-crop rotation– No-till crop production
Bartel farm: Stripped-crop rotation• Marion County
– French Creek Watershed
• Concerns
– Marion Reservoir
– Soil fertility and erosion
• Sampling: Runoff and groundwater
• Objectives: Nutrient concentrations relative to the crop rotation
Stripped-crop rotation: Soybeans and wheat
Monitoring program on the Bartel Farm
Field applications of “compost” around the sampling sites were unexpected
Mean* nutrient and herbicide concentrations: Upper site
TN in runoff at the upper sampler
1
10
100
0 20 40 60 90 120150180
Conce
ntr
atio
n (
mg/L
)Jun 23, 97Jul 29, 97Jul 16, 99Sep 14, 99May 26, 00
TP in runoff at the upper sampler
.1
1
10
0 20 40 60 90 120150180
Conce
ntr
atio
n (
mg/L
)
Jun 23, 97Jul 29, 97Jul 16, 99Sep 14, 99May 26, 00
Mean* nutrient and herbicide concentrations at the Bartel farm lower site
Sampling Date Rain TN TP AtrazineNov 16, 96 3.0 8.16 0.80 0.01Jun 23, 97 0.7 4.14 1.45 0.28Sep 24, 98 4.7 4.86 1.23 0.03Oct 2, 98 3.8 3.86 0.74 0.03Oct 31, 98 0.9 5.51 0.92 0.01Nov 10, 98 2.4 0.31 0.18 0.01Pre-application mean 3.74 0.89 0.06
"Compost" Added in Fall 98
Sampling Date Rain TN TP AtrazineJun 18, 99 1.1 9.83 1.22 0.75Jul 16, 99 1.9 13.44 2.82 0.30Sep 14, 99 1.7 22.06 3.39 0.01Nov 22, 99 2.4 19.53 3.58 0.18May 26, 00 1.5 35.31 10.28 0.47Jun 13, 00 0.9 20.67 4.71 0.47Jul 19, 00 1.0 35.09 7.98 0.13Post-application mean 22.28 4.85 0.33
TN in runoff at the lower samplerBartel farm
.1
1
10
100
0 20 40 60 90 120 150 180
Con
cent
ratio
n (m
g/L)
Time (minutes)
Sampling Date
Jun 23, 97Sep 24, 98Sep 25, 98Oct 2, 98Oct 31, 98Nov 10, 98
Before field applications After field applications
.1
1
10
100
0 20 40 60 90 120 150 180C
once
ntra
tion
(mg/
L)
Time (minutes)
Sampling Date
Jun 18, 99Jul 16, 99Sep 14, 99Nov 22, 99May 26, 00Jun 13, 00Jul 19, 00
TP in runoff at the lower samplerBartel farm
After field applications
.1
1
10
100
0 20 40 60 90120150180
Con
cent
ratio
n (m
g/L)
Sampling Date
Jun 23, 97Sep 24, 98Sep 25, 98Oct 2, 98Oct 31, 98Nov 10, 98
Before field applications
.1
1
10
100
0 20 40 60 90120150180
Con
cent
ratio
n (m
g/L)
Sampling Date
Jun 18, 99Jul 16, 99Sep 14, 99Nov 22, 99May 26, 00Jun 13, 00Jul 19, 00
SIMPLEX modeling on the Bartel farm
SIMPLEX Volume calculationsRunoff Volume
inches cm m3 TN TP TN kg/event TP kg/event TN kg/ha TP kg/haJun 23, 97 0.7 1.8 633.6 4.14 1.45 2.62 0.92 0.05 0.02Sep 24, 98 4.7 11.9 39540.1 4.86 1.23 192.16 48.63 3.68 0.93Oct 2, 98 3.8 9.7 29310.3 3.86 0.74 113.14 21.69 2.17 0.42Oct 31, 98 0.9 2.3 1476.1 5.51 0.92 8.13 1.36 0.16 0.03Nov 10, 98 2.4 6.1 13783.9 0.31 0.18 4.27 2.48 0.08 0.05Jun 18, 99 1.1 2.8 2617.9 9.83 1.22 25.73 3.19 0.49 0.06Jul 16, 99 1.9 4.8 8941.4 13.44 2.82 120.17 25.21 2.30 0.48Sep 14, 99 1.7 4.3 7153.3 22.06 3.39 157.80 24.25 3.02 0.46Nov 22, 99 2.4 6.1 13783.9 19.53 3.58 269.20 49.35 5.16 0.95May 26, 00 1.5 3.8 5445.6 35.31 10.28 192.28 55.98 3.68 1.07Jun 13, 00 0.9 2.3 1476.1 20.67 4.71 30.51 6.95 0.58 0.13Jul 19, 00 1.0 2.5 1916.1 35.09 7.98 67.24 15.29 1.29 0.29Sums 23.0 58.4 126078.3 1183.3 255.3 22.7 4.9
ExportSampling Date Rainfall 8 bottle mean Loading
Watershed area = 52.2 hectares or 130 Acres
Groundwater on the Bartel farm
• Two clusters• Sampled eleven times
• Nitrogen
• Phosphorus
• Atrazine
Total nitrogen in groundwater at both sites
0.0
0.5
1.0
1.5
2.0
2.5
Jul 19, 96
Jun 14, 97
Aug 7, 97
Jul 22, 98
A
ug 4, 98
Dec 2, 98
Jul 15, 99
S
ep 7, 99
Dec 8, 99
M
ay 13, 00
Jul 19, 00
Upper Site
Con
cent
ratio
n (m
g/L)
0.0
16.0
32.0
48.0
64.0
80.0
Jul 19, 96
Jun 14, 97
Aug 7, 97
Jul 22, 98
Aug 4, 98
Dec 2, 98
Jul 15, 99
Sep 7, 99
D
ec 8, 99
May 13, 00
Jul 19, 00
Lower site
Depth (ft) 1 4 8
Bartel farm stripped-crop rotation
0.0
0.1
0.2
0.3
0.4
0.5
Jul 19, 96
Jun 14, 97
Aug 7, 97
Jul 22, 98
A
ug 4, 98
Dec 2, 98
Jul 15, 99
S
ep 7, 99
Dec 8, 99
M
ay 13, 00
Jul 19, 00
Upper Site
Con
cent
ratio
n (m
g/L)
0.0
0.1
0.2
0.3
0.4
0.5
Jul 19, 96
Jun 14, 97
Aug 7, 97
Jul 22, 98
A
ug 4, 98
Dec 2, 98
Jul 15, 99
S
ep 7, 99
Dec 8, 99
M
ay 13, 00
Jul 19, 00
Lower Site
Depth (ft) 1 4 8
Total phosphorus in groundwater at both sites
Bartel farm stripped-crop rotation
Monitoring crop production systems
• Land management practices– Stripped-crop rotation– No-till crop production
Peters Farm: No-Till• Marion County
– South Cottonwood Watershed
• Concerns
– Nutrients and herbicides in runoff
– Groundwater contamination
– Soil erosion
Sampling: Runoff and groundwater
Objectives: Monitor trends in nutrient and herbicide concentrations relative to no-till practices.
Residue management at Peters farm
Conventional tillage on neighboring farm
Monitoring program on the Peters farm
Mean* nutrient and herbicide concentrationsPeters No-till farm
Sampling Date Rain TN TP AtrazineJun 22, 98 2.3 3.06 0.49 2.45
Sep 20, 980 1.2 2.53 1.69 0.13
Oct 2, 981 1.1 1.46 1.03 0.10
Oct 11, 981 1.5 0.32 0.01 0.02
Nov 10, 981 0.5 2.58 0.81 -Jun 16, 99 0.5 3.37 0.34 45.36Pre-construction mean 2.22 0.73 9.61
Aug 1, 99 2.1 8.52 1.08 26.87Nov 22, 99 2.5 19.53 3.53 -Site mean 14.03 2.31 12.08
Construction on grassed waterway
TN in first flush runoff on the Peters farm
.1
1
10
100
0 20 40 60 90 120 150 180
Con
cent
ratio
n (m
g/L)
Time (minutes)
Sampling DateJun 22, 98Sep 20, 98Oct 2, 98Oct 11, 98Nov 10, 98Jun 16, 99Aug 1, 99Nov 22, 99
TP in first flush runoff on the Peters farm
.001
.01
.1
1
10
0 20 40 60 90 120 150 180
Con
cent
ratio
n (m
g/L)
Time (minutes)
Sampling DateJun 22, 98Sep 20, 98Oct 2, 98Oct 11, 98Nov 10, 98Jun 16, 99Aug 1, 99Nov 22, 99
Atrazine in first flush runoff on the Peters farm
.001
.01
.1
1
10
100
1000
0 20 40 60 90 120 150 180
Con
cent
ratio
n (u
g/L)
Time (minutes)
Sampling DateJun 22, 98Sep 20, 98Oct 2, 98Oct 11, 98Jun 16, 99Aug 1, 99
Kansas statewide average: 1.12 ug/L Watershed average: 1.54 ug/L
SIMPLEX Modeling on the Peters farm
SIMPLEX Volume calculations
Sampling Date Runoff Volumeinches cm m3 TN TP TN kg/event TP kg/event TN kg/ha TP kg/ha
Jun 22, 98 2.2 5.6 12758 3.06 0.49 39.0 6.3 0.49 0.08
Sep 20, 980 4.2 10.7 42707 2.53 1.69 108.0 72.2 1.36 0.91Oct 02, 98 4.1 10.4 41001 1.46 1.3 59.9 53.3 0.75 0.67Oct 11, 98 1.5 3.8 5099 0.32 0.01 1.6 0.1 0.02 0.00Nov 10, 98 5.8 14.7 40695 5.58 0.81 227.1 33.0 2.86 0.42Jun 16, 99 0.5 1.3 147 3.37 0.34 0.5 0.05 0.01 0.00Aug 1, 99 0.4 1.0 303 8.52 0.44 2.6 0.1 0.03 0.00Nov 22, 99 2.4 6.1 14915 5.79 3.53 86.4 52.6 1.09 0.66Sums 21.1 53.6 157624.1 525.1 217.6 6.6 2.7
8 bottle mean ExportRainfall Loading
Watershed area = 79.4 hectares or 196 acres
Groundwater at the Peters farm
• Sampled 8 times at one location
• TN < 1.0 mg/L• TP < 0.06 mg/L• Atrazine < 0.2 ug/L
Monitoring livestock operations
• Land management practices– Land conversion – Rotational grazing
Townsend farm: Convert cropland to pasture
• Dickinson County
– Deer Creek Watershed
• Concerns
– Erosion of HEL
– Nutrients from cropland
Sampling: Runoff and groundwater
Objectives: Monitor trends in nutrient concentrations relative to the conversion
Continuous wheat alfalfa and fescue
Monitoring program on the Townsend farm
Mean* nutrient and herbicide concentrations in runoff Townsend farm
Sampling Date Rain TN TP Atrazine
Jul 28, 97 0.8 3.72 1.19 0.01
Jul 7, 98 0.5 2.81 0.79 0.42
Jul 30, 98 3.7 3.14 0.68 0.16
Aug 26, 98 0.8 9.73 2.39 0.05
Sep 24, 98 1.1 3.50 1.13 0.03
Sep 30, 98 1.3 4.09 1.02 0.03
Oct 17, 98 1.4 2.66 0.81 1.00
Nov 1, 98 4.9 1.56 0.43 0.21
Jun 18, 99 0.8 2.91 1.04 0.21
Aug 2, 99 3.6 1.41 0.94 0.26
4.1 1.04 0.14Site Mean Value
Total nitrogen in runoff: 1998
.1
1
10
100
0 20 40 60 90 120 150 180
Co
nce
ntr
atio
n (
mg
/L)
Time (minutes)
Sampling DateJul 7, 98Jul 30, 98Aug 26, 98Sep 24, 98Sep 30, 98Oct 17, 98Nov 1, 98
Townsend farm
.1
1
10
0 20 40 60 90 120 150 180
Con
cent
ratio
n (m
g/L)
Time (minutes)
Sampling DateJul 7, 98Jul 30, 98Aug 26, 98Sep 24, 98Sep 30, 98Oct 17, 98Nov 1, 98
Total phosphorus in runoff: 1998Townsend farm
SIMPLEX Modeling on the Townsend farm
SIMPLEX Volume calculations
Sampling Date Runoff Volumeinches cm m3 TN TP TN kg/event TP kg/event TN kg/ha TP kg/ha
Jul 28, 97 0.8 2.0 420.3 3.72 1.19 1.6 0.5 0.1 0.0Jul 7, 98 0.5 1.3 36.5 2.81 0.79 0.1 0.0 0.0 0.0Jul 30, 98 3.7 9.4 12221.9 3.14 0.68 38.4 8.3 1.7 0.4Aug 26, 98 0.8 2.0 420.3 9.73 2.39 4.1 1.0 0.2 0.0Sep 24, 98 1.1 2.8 1112.7 3.5 1.13 3.9 1.3 0.2 0.1Sep 30, 98 1.3 3.3 1701.8 4.09 1.02 7.0 1.7 0.3 0.1Oct 17, 98 1.4 3.6 2032.8 2.66 0.81 5.4 1.6 0.2 0.1Nov 1, 98 4.9 12.4 18470.7 1.56 0.43 28.8 7.9 1.2 0.3Jun 18, 99 0.8 2.0 420.3 2.91 1.04 1.2 0.4 0.1 0.0Aug 2, 99 3.6 9.1 11706.1 1.41 0.94 16.5 11.0 0.7 0.5Sum 18.9 48.0 48543.4 106.9 33.9 4.6 1.5
8 bottle mean ExportRainfall Loading
Watershed area = 23.1 hectares or 57 acres
Groundwater at the Townsend farm• Three clusters sampled eight times at 8 feet• Total nitrogen: 2 - 5 mg/L• Total phosphorus: Two clusters < 0.5 mg/L
Upper cluster 0.5 – 1.5 mg/L• Atrazine: All clusters < 0.2 ug/L
Monitoring livestock operations
• Land management practices– Land conversion – Rotational grazing
•Marshall County
–Lower Black Vermillion Watershed
•Concerns
–Flooding from creek
–Soil erosion
–Nutrients in runoff
Sampling: Runoff and groundwater
Objectives: Monitor trends in nutrient concentrations relative to rotational grazing.
Howell Farm: Rotational Grazing
Monitoring program on the Howell farm
Mean* nutrient and herbicide concentrationsHowell farm
Sampling Date Rain TN TP AtrazineJun 9, 98 1.2 6.61 2.46 0.25Sep 28, 98 4.4 1.92 1.65 0.12Nov 10, 98 1.0 3.34 1.83 0.01Jun 22, 99 0.8 4.09 0.41 0.20Jun 2, 00 0.8 2.53 2.42 0.26Jul 17, 00 1.8 1.63 1.43 0.05
3.34 1.70 0.18Site Mean Value
Total Nitrogen
1
10
100
0 20 40 60 90 120 150 180
Co
nce
ntr
atio
n (
mg
/L)
Time (minutes)
Sampling DateJun 9, 98Sep 28, 98Nov 1, 98Jun 22, 99Jun 20, 00Jul 17, 00
Total Phosphorus
.1
1
10
0 20 40 60 90 120 150 180
Co
nce
ntr
atio
n (
mg
/L)
Time (minutes)
Sampling DateJun 9, 98Sep 28, 98Nov 1, 98Jun 22, 99Jun 20, 00Jul 17, 00
SIMPLEX Modeling on the Howell farm
SIMPLEX Volume calculations
Sampling Date Runoff Volumeinches cm m3 TN TP TN kg/event TP kg/event TN kg/ha TP kg/ha
Jun 11, 98 1.2 3.0 1640 6.61 2.46 10.8 4.0 0.33 0.12Sep 28, 98 4.4 11.2 20943 1.92 1.65 40.2 34.6 1.22 1.05Nov 10, 98 1.0 2.5 931 3.34 1.83 3.1 1.7 0.09 0.05Jun 22, 99 0.8 2.0 468 4.09 0.41 1.9 0.2 0.06 0.01Jun 2, 00 0.8 2.0 468 2.53 2.42 1.2 1.1 0.04 0.03Jul 17, 00 1.8 4.6 4268 1.63 1.43 7.0 6.1 0.21 0.18Sums 10 25.4 28717 64.2 47.7 1.9 1.4
8 bottle mean ExportRainfall Loading
Watershed area = 33 hectares or 82 acres
Groundwater at the Howell farm• Three clusters
– Field
– Edge
– Riparian
• Sampled 8 times
Review so far
• Four farms with different land management
• Runoff and groundwater concentrations
• SIMPLEX calculates volumes for loading values
Important Questions• What are typical edge of field concentrations relative to
different land management practices ?
• What factors influence agricultural water quality?
• How do experimental values compare to the expected values?
• Can changes in land management lower nutrient and herbicide levels in groundwater and field runoff ?
TN in groundwater
.01
.1
1
10
100
Bartel-1
Bartel-2
How
ell-1
How
ell-2
How
ell-3
Peters-1
Townsend-1
Townsend-2
Townsend-3
TNC
once
ntra
tion
(mg/
L)
TP in groundwater
.001
.01
.1
1
10
Bartel-1
Bartel-2
How
ell-1
How
ell-2
How
ell-3
Peters-1
Townsend-1
Townsend-2
Townsend-3
TP
Con
cent
ratio
n (m
g/L)
Runoff TN concentrations by land use
.1
1
10
100
B-Low
er
B-M
anure
H-G
razing
P-N
o-till
T-Conversion
Con
cent
ratio
n (m
g/L)
Runoff TP concentrations by land use
.001
.01
.1
1
10
100
B-Low
er
B-M
anure
H-G
razing
P-N
o-till
T-Conversion
Con
cent
ratio
n (m
g/L)
Important Questions• What are typical edge of field concentrations relative to
different land management practices ?
• What factors influence agricultural water quality?
• How do experimental values compare to the expected values?
• Can changes in land management lower nutrient and herbicide levels in groundwater and field runoff ?
What affects runoff concentrations
• Natural levels of N and P (soils)
• Applications (B and P)
• Land cover (T and P)
• Hydrograph
• What does runoff hydrograph look like?
• Is 8-bottle mean a representative concentration?
Important Questions• What are typical edge of field concentrations relative to
different land management practices ?
• What factors influence agricultural water quality?
• How do experimental values compare to the expected values?
• Can changes in land management lower nutrient and herbicide levels in groundwater and field runoff ?
Experimental TN and TP loading Values
CropRain TN TP Factor TN TP
Bartel 23 22.7 4.9 1.4 31.6 6.8Peters 21 6.6 2.7 1.5 10.1 4.1
KS annual rain = 32 inches
GrazingRain TN TP Factor TN TP
Townsend 19 4.6 1.5 1.7 7.7 2.5Howell 10 1.9 1.4 3.2 6.1 4.5
kg/ha/yrkg/ha
kg/ha kg/ha/yr
Loading values from literature
Total phosphorus (kg/ha/yr)Rowcrops Rowcrops
Mean 16.09 Mean 4.46Median 9.00 Median 2.24Range 2.1 79.6 Range 0.26 18.6
Grazing GrazingMean 8.65 Mean 1.50Median 5.19 Median 0.81Range 1.48 30.85 Range 0.14 4.90
Total Nitrogen (kg/ha/yr)
Comparing loading values
Research• Crop production
TN: 10.1 and 31.6TP: 4.1 and 6.8
• Livestock OperationsTN: 6.1-7.7TP: 2.5-4.5
Literature• Crop production
TN: 2.1 to 79.6TP: 4.1 to 6.8
• Livestock Operations TN: 0.26 to 18.6TP: 0.14 to 4.90
Modeling Issues
Loading = Volume X Concentration
Scale issues affect volume?
Representative concentrations?
Research Conclusions• Runoff and groundwater concentration data varied in a
wide but acceptable range.
• Applications, ground cover and weather patterns impact agricultural water quality.
• Loading values calculated using SIMPLEX and empirical data are similar to literature.
• However, BMPs are not likely to cause noticeable decreases in nutrient and herbicide concentrations in the short term.
Future study possibilities
• Identify NPSP “hotspots”
• Determine field-scale runoff hydrograph
Special Thanks
• Kansas Rural Center
• Bartels, Peters, Townsends and Howells
• KBS: Steve, Jeff, Don, Chip and Jerry
YOU