mitigation options for phosphorus and sediment (mops ... · mitigation options for phosphorus and...
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Mitigation options for phosphorus and sediment (MOPS): overview and results of
the first two years(Defra PE0206)
1Lancaster Environment Centre, Lancaster University, UK2 ADAS Wolverhampton, UK 3Department of Agriculture, University of Reading, UK
John Quinton 1, Clare Deasy 1, Carly Stevens 1, Martyn Silgram 2, Bob Jackson 2 ,Alison Bailey 3,
Louise Heathwaite 1
About MOPS
• Review of mitigation measures• Testing of mitigating measures for
sediment and P losses in the surface pathway
• Development of rare earth oxide tracers• Economic analysis
Focus on arable agriculture
Focus on overland flow
Field Monitoring Approach
• Three field sites with different soil types
• 52 hillslope length unbounded plots
Loddington
Field Sites
Hattons
Rosemaund
• Rosemaund, Herefordshire (silty clay loam soils) ADAS
• Hattons, Staffordshire (sandy soils) Severn Trent Water
• Loddington, Leicestershire (clay soils) Allerton Trust
Mitigation measures
• Loddington– Contour cultivation– Minimum tillage– Vegetative barriers
• Rosemaund– Tramline management
• Hattons– Tramline management– Crop residues
LoddingtonTreatments:
– Up & down minimum tillage (MT)
– Contour minimum tillage (MT C)– Contour minimum tillage with beetle bank (MT C BB)
– Contour plough with beetle bank (P C BB)– Contour plough (P C)– Up & down plough (P)
Contour Cultivation
Up/Down Slope Cultivation
Up/Down Slope Cultivation
PloughMinimum Tillage
N
EventsTwenty events monitored between 1st October & 1st May 2005-2006 & 2006-2007
0
20
40
60
80
100
120
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Event
Rainfall (mm)
Runoff Coefficient (%)
2005-2006 2006-2007
3125Median Event Size (mm)
3638Mean Event Size (mm)
359383Total Rain (mm)
06-0705-06Rainfall Summary
Concentrations
0
750
1500
2250
3000
MT MT C MT C BB P C BB P C P
SS
(mg
l-1
)
0
3
6
9
12
MT MT C MT C BB P C BB P C P
N
(mg
l-1
)
TN
TDN
0
1
2
3
4
MT MT C MT C BB P C BB P C P
P
(mg
l-1
)
TP
TDP
• Large variation in data between events
• Particulate losses dominant for P, but not N
• Beetle bank reduces SS & P concentrations
• Contour ploughing increases concentrations of particulate material?
MT = minimum tillage P = ploughC = contour cultivation BB = beetle bank
n=20
Runoff
0
25
50
75
100
MT MT C MT C BB P C BB P C P
Run
off
(m3
ha-1)• Higher for
ploughed treatments
• Reduced for contour treatments, under minimum tillage or with vegetative barrier
MT = minimum tillage P = ploughC = contour cultivation BB = beetle bank
276873926P
408313100193P C
1731731017P C BB
2402345966MT C BB
651489185MT C
5875571358MT
±Mean±Mean
All 06-07All 05-06
Average Runoff Yield for each Treatment (m3 ha-1)
Treatment
Phosphorus
0.00
0.05
0.10
0.15
0.20
MT MT C MT C BB P C BB P C P
P Y
ield
(kg
ha-1)
TPTDP• Losses higher
for ploughed treatments
• Losses reduced under minimum tillage, contour cultivation or with vegetative barrier
MT = minimum tillage P = ploughC = contour cultivation BB = beetle bank
0.341.660.010.03P
0.820.660.090.14P C
0.440.450.010.01P C BB
0.330.380.090.09MT C BB
0.150.410.100.34MT C
0.800.800.010.09MT
±Mean±Mean
All 06-07All 05-06
Average TP Yield for each Treatment (kg ha-1)
Treatment
n=20
Nitrogen
0.0
0.1
0.2
0.3
0.4
MT MT C MT C BB P C BB P C P
N Y
ield
(kg
ha-1)
TN
TDN• Similar losses
for plough and minimum tillage
• Losses reduced with vegetative barrier
MT = minimum tillage P = ploughC = contour cultivation BB = beetle bank
0.923.590.280.37P
1.681.341.201.28P C
0.920.940.040.08P C BB
0.830.930.750.62MT C BB
0.370.900.854.62MT C
2.752.650.151.09MT
±Mean±Mean
All 06-07All 05-06
Average TN Yield for each Treatment (kg ha-1)
Treatment
n=20
Findings (recommendations) so far…
For the particulate load– Contour ploughing– Minimum-tillage– Contour grass stripsBut..– Farmers (our farmer) don’t like contour grass
barrier strips
Hattons and Rosemaund
Tramline (wheeling or tyre track) disruption
Experimental treatments• Four replicate hillslope lengths for each
treatment
• Rosemaund (Silty clay loam)o Tramline, no tramlineo Tramline disruption
• Hattons (Sandy loam)o Tramline, no tramlineo Straw baled/removedo Straw chopped/spread
A27 West of Lille,France
Close to Valladolid,Spain
Close to Oslo,Norway
Close to Vienna,Austria
Hattons: aerial view
Tramline disruption
Conventional tramline
Disrupted tramline
Offset tramline
1st winter results: HattonsAggregated over-winter fluxes 05/06 (eight events)
Summary results Runoff Runoff % rainfall Sediment TP TNWinter 05/06 mm litres as runoff kg/ha kg/ha kg/haBaled No tramline 0.4 312 0.2 21 0.06 0.09Baled Tramline 8.4 6802 6.8 499 1.52 1.83Chopped No tramline 0.2 172 0.1 12 0.03 0.04Chopped Tramline 6.4 5056 4.4 298 0.99 1.17
• >90% of TP present in particulate form
• Straw chopped/spread treatments had lower runoff, sediment, TP and TN fluxes
• Tramlines important pathway for surface loss
1st winter results: RosemaundAggregated over-winter fluxes, 05/06 (four events)
Summary results Runoff Runoff % rainfall Sediment TP TNWinter 05/06 mm litres as runoff kg/ha kg/ha kg/haNo tramline 0.3 63 0.5 3 0.01 0.03Tramline Not disrupted 5.8 1807 10.9 357 1.32 1.32Tramline Disrupted 0.3 105 0.6 6 0.02 0.06
• 77-85% TP present in particulate form
•Tramline disruption appears highly effective
Summary 1st winter results
• Dominant effect of tramlines as mechanism for field scale losses
• Mitigation tools:o Tramline disruption highly effective o Residue management moderately effective
Summary 2nd winter results:Hattons and Rosemaund
RM No tramline 2.0 825 21.4 0.0 0.0 80.5 45.9Drilled tramline - wheeled 77.8 28365 4776.3 2.9 5.3 94.8 74.5Drilled tramline - cultivated 2.7 1045 39.9 0.0 0.1 79.7 45.4Drilled tramline - offset 94.7 34476 6923.0 4.0 6.7 94.8 75.6
Effects of tramlines & mitigation more pronounced at RM
Runoff Runoff Sediment TP TN PP as %TP PN as %TNmm litres kg/ha kg/ha kg/ha
Hattons No tramline 2.7 2595 23.7 0.1 0.1 93.7 42.3Drilled tramline - wheeled 15.3 14450 274.9 0.8 1.0 95.6 58.0Drilled tramline - cultivated 5.0 4686 71.7 0.2 0.3 96.3 35.8Drilled tramline - offset 10.1 9582 131.5 0.4 0.5 95.3 46.3
Conclusions from three sites
• P losses primarily particulate• Cultivation methods reduce losses
– Contour ploughing– Minimum-tillage– Contour grass strips
• Residue management can prove beneficial• Importance of tramlines• Tramline disruption effective• Further work (LINK) needed to focus on
operational aspects of tramline disruption
Tramline disruption Straw removal
Contour cultivation
So what does it cost?
In-field vegetative strip
-€1.4 ha
+€1.4 ha-€14.5 ha-€3 ha+establishmentand maintenance
€0 ha
Minimum Tillage Straw incorporation
+€67 ha
Results: summary
Option Financial impact Effective
Minimum tillage Improves margin Potentially
Contour cultivation No change Potentially
Beetle bank Capital costReduces margin
Potentially
Tramline disruption Reduces margin Yes
Straw incorporation Reduces margin Yes