Appendix 2.

1

Cost curve of nitrate mitigation options NT2511

Description of arable measures

Code /
Description
/ Assumptions in modelling / Applicability to rotations / Implications for economics
Sand / Clay / Sand / Positive / Negative
-M / +M / -M / +M / Pigs
Plant-based
P3 / Grow cover crops and establish early. / Only before spring (root) crops that follow cereals (i.e. on sandy soil rotation). /  /  / No effects on N inputs or yield1 / Seed and establishment costs
P4 / Put land into long-term set-aside or low input grassland. / Assume 20% of rotation replaced by set-aside or nil N fertilised grass, i.e. taking land out of production. /  /  /  /  /  / Save inputs to 20% of land / Lose output from 20% of land.
Fertiliser-based
Fa1 / Use a reliable recommendation system / Determine yields and N fertiliser inputs based on RB209 recommendations. /  /  /  /  /  / Reduced fertiliser inputs where above recommended rates, with no economic penalty for yield.
Fa2 / Reduce the N fertiliser rate to 20% below the economic optimum / Reduce to 20% below the values in the baseline run. /  /  /  /  /  / Saves fertiliser inputs. / Possible (small) effects on yield.
Fa3 / Avoid autumn N applications in most circumstances / Only winter OSR on clay. Also tested the impacts of applying autumn N to cereals. /  /  /  /  /  / Reduced N inputs with little, if any yield penalty.
Fa5 / Adjust fertiliser rates to allow for N supplied in manure / Used MANNER to deduce fertiliser value of manure, than subtracted this from fertiliser applied /  /  / Reduced N inputs with no effects on yield.
Fa2_5 / Adjust fertiliser rates for manure and then reduce by a further 20% / Used MANNER to deduce fertiliser value of manure, than subtracted this from fertiliser applied. Then reduced by another 20%. /  /  /  / Reduced N inputs. / Reduced yield.
Manure-based
M1 / Avoid autumn applications - slurry, poultry manure, liquid digested sludge / Move Sept, Oct applications to 1 Feb on sand, 1 Mar on clay; no change to pig excreta (assumed all year). Do not adjust fertiliser inputs. /  /  / Increased storage costs
Specialist spreader?
M2 / Restrict manure applications to safe time windows / No manure before 1 Mar. Does not affect outdoor pigs. Do not adjust fertiliser inputs. /  /  / Increased storage costs
Specialist spreader?
M1_6
M2_6 / Manure timing and fertiliser adjustment / As for M1 or M2, but then adjust fertiliser rates using MANNER. Fertiliser inputs will decrease where a switch to spring manure applications saves N being lost by leaching. /  /  / Reduced N inputs with no loss of yield. / Increased storage costs
Specialist spreader?
Animal-based - pigs
Ap2 / Outdoor pigs - reduce the stocking rate / No crop fertiliser adjustment. Manure (representing pig excreta) simply halved. /  / Fewer pigs per unit area
Other and combined options
Z / Combined NVZ restrictions / Equivalent to M5 on sands, Fa5 on other soils. However, outdoor pigs would have to be reduced by around one third of the AP2 scenario or 2/3 of the baseline scenario. /  /  /  /  / 
Measures not tested
S3 / Cultivate leys in spring and establish crop as quickly as possible / No grass in these rotations: cannot apply this measure.
Fa8 / Use fertiliser placement for starter applications to vegetable crops / No vegetable crops in the rotations; not done
M3 / Apply manure at the optimum rate / Meaningless. Optimum is none at all since there is increased leaching regardless of how careful you are (in arable, anyway)

1scenario was also included that assumed a 10% yield increase for root crops following cover crops (based on one experiment: [27])

Fertiliser inputs and effects on yields for measures that affected fertiliser recommendations

Previous / Current / Man / Baseline / Fa1 / Fa2 / Fa5 / Fa5_2 / M1M5 / M2M6
Crop / Crop / kg/ha N / t/ha / kg/ha N / t/ha / kg/ha N / t/ha / kg/ha N / t/ha / kg/ha N / t/ha / kg/ha N / t/ha / kg/ha N / t/ha
WW / WB / 160 / 8.00 / 180 / 8.09 / 128 / 7.75 / 160 / 8.00 / 128 / 7.75 / 160 / 8.00 / 160 / 8.00
WB / WOSR / 210 / 4.00 / 190 / 3.97 / 168 / 3.89 / 210 / 4.00 / 168 / 3.89 / 210 / 4.00 / 210 / 4.00
WOSR / WW / 160 / 9.00 / 150 / 8.99 / 128 / 8.87 / 160 / 9.00 / 128 / 8.87 / 160 / 9.00 / 160 / 9.00
WW / W Beans / 0 / 4.00 / 0 / 4.00 / 0 / 4.00 / 0 / 4.00 / 0 / 4.00 / 0 / 4.00 / 0 / 4.00
W Beans / WW / 200 / 9.00 / 180 / 8.98 / 160 / 8.89 / 200 / 9.00 / 160 / 8.89 / 200 / 9.00 / 200 / 9.00
WW / WB / 160 / 8.03 / 180 / 8.09 / 128 / 7.81 / 160 / 8.03 / 128 / 7.81 / 160 / 8.03 / 160 / 8.03
WB / WOSR / 210 / 4.00 / 190 / 3.97 / 168 / 3.91 / 210 / 4.00 / 168 / 3.91 / 210 / 4.00 / 210 / 4.00
WOSR / WW /  / 160 / 9.01 / 120 / 8.99 / 128 / 9.02 / 110 / 9.00 / 88 / 8.93 / 82 / 9.00 / 82 / 9.00
WW / W Beans / 0 / 4.00 / 0 / 4.00 / 0 / 4.00 / 0 / 4.00 / 0 / 4.00 / 0 / 4.00 / 0 / 4.00
W Beans / WW /  / 200 / 9.00 / 150 / 8.98 / 160 / 9.01 / 150 / 9.00 / 120 / 8.93 / 122 / 9.00 / 122 / 9.00
SB / WW / 170 / 7.00 / 160 / 6.96 / 136 / 6.84 / 170 / 7.00 / 136 / 6.84 / 170 / 7.00 / 170 / 7.00
WW / Pots / 250 / 45.0 / 230 / 44.9 / 200 / 44.7 / 250 / 45.0 / 200 / 44.7 / 250 / 45.0 / 250 / 45.0
Pots / SW / 180 / 7.00 / 160 / 6.93 / 144 / 6.86 / 180 / 7.00 / 144 / 6.86 / 180 / 7.00 / 180 / 7.00
SW / WB / 170 / 6.50 / 160 / 6.47 / 136 / 6.37 / 170 / 6.50 / 136 / 6.37 / 170 / 6.50 / 170 / 6.50
WB / SBeet / 130 / 40.0 / 120 / 40.1 / 104 / 40.0 / 130 / 40.0 / 104 / 40.0 / 130 / 40.0 / 130 / 40.0
SBeet / SB / 80 / 6.00 / 90 / 6.07 / 64 / 5.82 / 80 / 6.00 / 64 / 5.82 / 80 / 6.00 / 80 / 6.00
SB / WW /  / 170 / 7.02 / 150 / 6.96 / 136 / 6.89 / 162 / 6.96 / 130 / 6.85 / 92 / 6.96 / 92 / 6.96
WW / Pots /  / 250 / 45.4 / 185 / 44.9 / 200 / 45.0 / 199 / 45.0 / 159 / 44.9 / 199 / 45.0 / 191 / 45.0
Pots / SW / 180 / 7.04 / 160 / 6.93 / 144 / 6.97 / 180 / 7.04 / 144 / 6.97 / 180 / 7.04 / 180 / 7.04
SW / WB / 170 / 6.52 / 160 / 6.47 / 136 / 6.47 / 170 / 6.52 / 136 / 6.47 / 170 / 6.52 / 170 / 6.52
WB / SBeet /  / 130 / 38.9 / 90 / 40.0 / 104 / 39.7 / 91 / 38.9 / 73 / 40.1 / 0 / 39.9 / 0 / 39.9
SBeet / SB /  / 80 / 5.92 / 20 / 6.07 / 64 / 6.02 / 19 / 6.12 / 15 / 6.11 / 19 / 6.12 / 11 / 6.09
WOSR / WW / 140 / 6.92 / 160 / 6.96 / 112 / 6.73 / 140 / 6.92 / 112 / 6.73 / 140 / 6.92 / 140 / 6.92
WW / Pots / 225 / 44.9 / 230 / 44.9 / 180 / 44.4 / 225 / 44.9 / 180 / 44.4 / 225 / 44.9 / 225 / 44.9
Pots / SW / 180 / 7.00 / 160 / 6.93 / 144 / 6.86 / 180 / 7.00 / 144 / 6.86 / 180 / 7.00 / 180 / 7.00
SW / Pigs /  / 0 / - / - / - / 0 / - / 0 / - / 0 / - / 0 / - / 0 / -
Pigs / Pigs /  / 0 / - / - / - / 0 / - / 0 / - / 0 / - / 0 / - / 0 / -
Pigs / WOSR / 200 / 3.45 / 160 / 3.47 / 160 / 3.50 / 145 / 3.45 / 116 / 3.43 / 145 / 3.45 / 200 / 3.45

Summary of nitrate leaching losses (dry climate): difference against baseline conditions. Values are calculated as Nloss (baseline) – Nloss (measure). Positive values are therefore reductions in N loss: negative values denote increases in N loss.

Previous / Current / Man. /
Baseline
/ P3 / P4* / Fa2 / Fa3 / Fa5 / Fa2_5 / M1 / M2 / M1_M5 / M2_M6 / AP2
Crop / Crop / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1
WW / WB / 23 / 0 / 22 / 3 / 0 / 0 / 3 / 0 / 0 / 0 / 0 / 0
WB / WOSR / 38 / 0 / 37 / 6 / 24 / 0 / 6 / 0 / 0 / 0 / 0 / 0
WOSR / WW / 43 / 0 / 42 / 7 / 0 / 0 / 7 / 0 / 0 / 0 / 0 / 0
WW / W Beans / 20 / 0 / 19 / 1 / 0 / 0 / 1 / 0 / 0 / 0 / 0 / 0
W Beans / WW / 41 / 0 / 40 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 0
WW / WB / 29 / 0 / 25 / 5 / 0 / 5 / 6 / -8 / -8 / 1 / 1 / 0
WB / WOSR / 39 / 0 / 38 / 6 / 24 / 0 / 6 / 0 / 0 / 0 / 0 / 0
WOSR / WW /  / 81 / 0 / 50 / 8 / 0 / 0 / 8 / 31 / 37 / 31 / 37 / 0
WW / W Beans / 22 / 0 / 20 / 1 / 0 / 1 / 2 / -6 / -6 / 0 / 0 / 0
W Beans / WW /  / 79 / 0 / 47 / 0 / 0 / 0 / 0 / 31 / 37 / 31 / 37 / 0
SB / WW / 46 / 0 / 44 / 1 / 0 / 0 / 1 / 0 / 0 / 0 / 0 / 0
WW / Pots / 17 / 10 / 15 / 2 / 0 / 0 / 2 / 0 / 0 / 0 / 0 / 0
Pots / SW / 56 / 0 / 54 / 22 / 0 / 0 / 22 / 0 / 0 / 0 / 0 / 0
SW / WB / 7 / 0 / 5 / 1 / 0 / 0 / 1 / 0 / 0 / 0 / 0 / 0
WB / SBeet / 20 / 12 / 18 / 4 / 0 / 0 / 4 / 0 / 0 / 0 / 0 / 0
SBeet / SB / 3 / 0 / 1 / -3 / 0 / 0 / -3 / 0 / 0 / 0 / 0 / 0
SB / WW /  / 177 / 0 / 62 / 4 / 0 / 7 / 8 / 31 / 74 / 38 / 91 / 0
WW / Pots /  / 84 / 30 / 31 / 9 / 0 / 2 / 9 / -7 / 8 / 10 / 31 / 0
Pots / SW / 121 / 0 / 87 / 25 / 0 / 26 / 45 / 0 / -15 / 26 / 14 / 0
SW / WB / 18 / 0 / 4 / 5 / 0 / 0 / 5 / 0 / 0 / 0 / 0 / 0
WB / SBeet /  / 184 / 55 / 70 / 6 / 0 / 0 / 6 / 69 / 144 / 69 / 144 / 0
SBeet / SB /  / 90 / 0 / 40 / 13 / 0 / 20 / 29 / -7 / -7 / 29 / 58 / 0
WOSR / WW / 84 / 0 / 67 / 20 / 0 / 28 / 37 / 0 / 0 / 28 / 0 / 14
WW / Pots / 20 / 12 / 15 / 2 / 0 / 0 / 2 / 0 / 0 / 0 / 0 / 3
Pots / SW / 44 / 0 / 41 / 14 / 0 / 0 / 14 / 0 / 0 / 0 / 0 / 0
SW / Pigs /  / 141 / 0 / 13 / 3 / 0 / 0 / 3 / 0 / 0 / 0 / 0 / 64
Pigs / Pigs /  / 459 / 0 / 279 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 174
Pigs / WOSR / 358 / 0 / 289 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 123

*100% set-aside

Summary of nitrate leaching losses (wet climate): difference against baseline conditions. Values are calculated as Nloss (baseline) – Nloss (measure). Positive values are therefore reductions in N loss: negative values denote increases in N loss.

Previous / Current / Man. /
Baseline
/ P3 / P4* / Fa2 / Fa3 / Fa5 / Fa2_5 / M1 / M2 / M1_M5 / M2_M6 / AP2
Crop / Crop / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1 / kg N ha-1
WW / WB / 41 / 0 / 39 / 2 / 0 / 0 / 2 / 0 / 0 / 0 / 0 / 0
WB / WOSR / 74 / 0 / 72 / 11 / 47 / 0 / 11 / 0 / 0 / 0 / 0 / 0
WOSR / WW / 82 / 0 / 81 / 13 / 0 / 0 / 13 / 0 / 0 / 0 / 0 / 0
WW / W Beans / 38 / 0 / 36 / 2 / 0 / 0 / 2 / 0 / 0 / 0 / 0 / 0
W Beans / WW / 80 / 0 / 79 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 0
WW / WB / 51 / 0 / 44 / 6 / 0 / 2 / 6 / -15 / -15 / 3 / 3 / 0
WB / WOSR / 77 / 0 / 74 / 11 / 47 / 0 / 11 / 0 / 0 / 0 / 0 / 0
WOSR / WW /  / 157 / 0 / 96 / 14 / 0 / 0 / 14 / 67 / 72 / 67 / 72 / 0
WW / W Beans / 43 / 0 / 38 / 2 / 0 / 0 / 2 / -10 / -10 / 1 / 1 / 0
W Beans / WW /  / 155 / 0 / 92 / 0 / 0 / 0 / 0 / 67 / 72 / 67 / 72 / 0
SB / WW / 46 / 0 / 44 / 1 / 0 / 0 / 1 / 0 / 0 / 0 / 0 / 0
WW / Pots / 17 / 0 / 15 / 2 / 0 / 0 / 2 / 0 / 0 / 0 / 0 / 0
Pots / SW / 56 / 0 / 54 / 22 / 0 / 0 / 22 / 0 / 0 / 0 / 0 / 0
SW / WB / 7 / 0 / 5 / 1 / 0 / 0 / 1 / 0 / 0 / 0 / 0 / 0
WB / SBeet / 20 / 12 / 18 / 4 / 0 / 0 / 4 / 0 / 0 / 0 / 0 / 0
Sbeet / SB / 3 / 0 / 1 / -3 / 0 / 0 / -3 / 0 / 0 / 0 / 0 / 0
SB / WW /  / 177 / 0 / 62 / 4 / 0 / 6 / 6 / 31 / 74 / 36 / 91 / 0
WW / Pots /  / 84 / 30 / 31 / 9 / 0 / 2 / 9 / -7 / 8 / 9 / 31 / 0
Pots / SW / 121 / 0 / 87 / 25 / 0 / 16 / 37 / 0 / -15 / 16 / 14 / 0
SW / WB / 18 / 0 / 4 / 5 / 0 / 0 / 5 / 0 / 0 / 0 / 0 / 0
WB / SBeet /  / 184 / 55 / 70 / 6 / 0 / 0 / 6 / 69 / 144 / 69 / 144 / 0
SBeet / SB /  / 90 / 0 / 40 / 13 / 0 / 19 / 28 / -7 / -7 / 36 / 58 / 0
WOSR / WW / 84 / 0 / 67 / 20 / 0 / 12 / 29 / 0 / 0 / 12 / 0 / 14
WW / Pots / 20 / 12 / 15 / 2 / 0 / 0 / 2 / 0 / 0 / 0 / 0 / 3
Pots / SW / 44 / 0 / 41 / 14 / 0 / 0 / 14 / 0 / 0 / 0 / 0 / 0
SW / Pigs /  / 141 / 0 / 13 / 3 / 0 / 0 / 3 / 0 / 0 / 0 / 0 / 64
Pigs / Pigs /  / 459 / 0 / 279 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 174
Pigs / WOSR / 358 / 0 / 289 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 0 / 123

*100% set-aside

Summary of the effectiveness of individual measures. NB: measures showing a positive cost benefit have had costs set at zero.

Clay dry manure / kg ha-1 / £ ha-1 / Cum N / Cum £ / Sand dry manure / kg ha-1 / £ ha-1 / Cum N / Cum £
Fa5 / Account for manure / 1.4 / 0.0 / 1.4 / 0.0 / Fa2 Fa5 / Fa5, then decrease N by 20% / 17.1 / 0.0 / 17.1 / 0.0
Fa1 / Improved fertiliser recs / 2.5 / 0.0 / 3.9 / 0.0 / Fa5 / Account for manure / 9.1 / 0.0 / 26.2 / 0.0
Fa2 Fa5 / Fa5, then decrease N by 20% / 4.4 / 0.0 / 8.3 / 0.0 / Fa1 / Improved fertiliser recs / 5.6 / 0.0 / 31.8 / 0.0
Fa2 / Reduce N fertiliser by 20% / 3.9 / 0.0 / 12.1 / 0.0 / Fa2 / Reduce N fertiliser by 20% / 10.4 / 0.0 / 42.3 / 0.0
Fa3 / No autumn N / 4.7 / 4.0 / 16.9 / 4.0 / P3 / Cover crop on sandy soils / 14.1 / 8.9 / 56.3 / 8.9
M1 M5 / Plus account for manure / 12.8 / 54.9 / 29.7 / 59.0 / M2 M6 / Plus account for manure / 56.3 / 82.9 / 112.6 / 91.7
M2 M6 / Plus account for manure / 15.1 / 54.9 / 44.8 / 113.9 / M1 M5 / Plus account for manure / 28.7 / 83.4 / 141.4 / 175.1
M1 / Manure timing / 9.8 / 66.0 / 54.6 / 179.9 / M1 / Manure timing / 14.4 / 104.2 / 155.8 / 279.3
M2 / Manure timing / 12.1 / 66.0 / 66.6 / 245.9 / M2 / Manure timing / 33.9 / 104.2 / 189.7 / 383.4
P4 / Premium grass (20%) / 7.0 / 89.4 / 73.6 / 335.3 / P4 / Premium grass (20%) / 10.0 / 112.2 / 199.7 / 495.7
Clay wet manure / kg ha-1 / £ ha-1 / Cum N / Cum £ / Sand wet manure / kg ha-1 / £ ha-1 / Cum N / Cum £
Fa5 / Account for manure / 0.5 / 0.0 / 0.5 / 0.0 / Fa2 Fa5 / Fa5, then decrease N by 20% / 15.4 / 0.0 / 15.4 / 0.0
Fa1 / Improved fertiliser recs / 4.8 / 0.0 / 5.3 / 0.0 / Fa5 / Account for manure / 7.1 / 0.0 / 22.5 / 0.0
Fa2 Fa5 / Fa5, then decrease N by 20% / 6.7 / 0.0 / 12.0 / 0.0 / Fa1 / Improved fertiliser recs / 5.6 / 0.0 / 28.2 / 0.0
Fa2 / Reduce N fertiliser by 20% / 6.6 / 0.0 / 18.6 / 0.0 / Fa2 / Reduce N fertiliser by 20% / 10.4 / 0.0 / 38.6 / 0.0
Fa3 / No autumn N / 9.3 / 4.0 / 27.9 / 4.0 / P3 / Cover crop on sandy soils / 14.1 / 8.9 / 52.7 / 8.9
M1 M5 / Plus account for manure / 27.4 / 54.9 / 55.3 / 59.0 / M2 M6 / Plus account for manure / 56.3 / 82.9 / 109.0 / 91.7
M2 M6 / Plus account for manure / 29.7 / 54.9 / 85.0 / 113.9 / M1 M5 / Plus account for manure / 27.8 / 83.4 / 136.7 / 175.1
M1 / Manure timing / 21.7 / 66.0 / 106.7 / 179.9 / M1 / Manure timing / 14.4 / 104.2 / 151.2 / 279.3
M2 / Manure timing / 24.0 / 66.0 / 130.7 / 245.9 / M2 / Manure timing / 33.9 / 104.2 / 185.1 / 383.4
P4 / Premium grass (20%) / 14.0 / 89.4 / 144.7 / 335.3 / P4 / Premium grass (20%) / 10.0 / 113.2 / 195.1 / 496.6
Clay dry / kg ha-1 / £ ha-1 / Cum N / Cum £ / Sand dry / kg ha-1 / £ ha-1 / Cum N / Cum £
Fa1 / Improved fertiliser recs / 1.6 / 0.0 / 1.6 / 0.0 / Fa2 / Reduce N fertiliser by 20% / 4.4 / 0.0 / 4.4 / 0.0
Fa2 / Reduce N fertiliser by 20% / 3.4 / 0.0 / 5.0 / 0.0 / Fa1 / Improved fertiliser recs / 1.2 / 0.0 / 5.7 / 0.0
Fa3 / No autumn N / 4.7 / 4.0 / 9.8 / 4.0 / Fa2 Fa5 / Fa5, then decrease N by 20% / 4.4 / 0.0 / 10.1 / 0.0
P4 / Premium grass (20%) / 6.0 / 93.4 / 15.8 / 97.5 / P3 / Cover crop on sandy soils / 3.7 / 8.9 / 13.8 / 8.9
P4 / Premium grass (20%) / 5.0 / 112.2 / 18.8 / 121.1

1

Cost curve of nitrate mitigation options NT2511

Summary of assumptions used to calculate costs and saving implications from individual measures.

Description of measure / Assumed additional costs / Assumed additional savings
P3 / Cover crop on sandy soils /
  • W. barley seed for cover crop.
  • Broadcast and disc.
/
  • No effects on yield.
  • Also calculated as boosting yield by 10%

P4 / Premium grass (20%) /
  • Loss of yield.

Fa1 / Improved fertiliser recs /
  • Small yield penalty in some circumstances.
/
  • Generally, fertiliser N savings.
  • Sometimes, no yield penalty.

Fa2 / Reduce N fertiliser by 20% /
  • Small yield penalty.
/
  • Generally, fertiliser N savings.
  • Sometimes, no yield penalty.

Fa3 / No autumn N /
  • Small yield penalty (OSR only).
/
  • Fertiliser N savings.

Fa5 / Account for manure /
  • Fertiliser N savings.

Fa2 Fa5 / Fa5, then decrease N by 20% /
  • Yield penalty.
/
  • Fertiliser N savings.

M1 / Manure timing /
  • Additional storage costs.
  • Contractor costs for spreading with specialist equipment.

M2 / Manure timing /
  • Additional storage costs.
  • Contractor costs for spreading with specialist equipment.

M1 M5 / Plus account for manure /
  • Additional storage costs.
  • Contractor costs for spreading with specialist equipment.
/
  • Fertiliser N savings.

M2 M6 / Plus account for manure /
  • Additional storage costs.
  • Contractor costs for spreading with specialist equipment.
/
  • Fertiliser N savings.

AP2 / Reduce pig numbers /
  • Less output.
/
  • Feed savings

1

Cost curve of nitrate mitigation options NT2511

Summary of the cost-effectiveness of individual measures. Costs were calculated as farming costs (baseline) – farming costs (measure). Negative values denote cost to farmer, positive values denote zero cost or possible savings to be made by implementation of measures.

Measure / Clay / Sand
Manure / No / Manure / No / Pigs
Dry / Wet / Dry / Wet / Dry / Wet / Dry / Wet / Dry / Wet
Baseline NO3-N losses (kg ha-1) / 50 / 96 / 33 / 63 / 113 / 113 / 25 / 25 / 184 / 184
P3 / Cover crop on sandy soils / n/a / n/a / n/a / n/a / -0.6 / -0.6 / -2.4 / -4.4 / -2.2 / -2.2
P4 / Premium grass (20%) / -12.8 / -6.4 / -15.6 / -7.8 / -11.2 / -11.3 / -22.5 / -22.6 / -7.2 / -7.2
Fa1 / Improved fertiliser recs / 2.3 / 1.2 / 0.7 / 0.4 / 2 / 2 / 1.3 / 1.3 / 0.2 / 0.2
Fa2 / Reduce N fertiliser by 20% / 1.3 / 0.8 / 0.1 / 0 / 0.8 / 0.8 / 0.2 / 0.2 / -0.1 / -0.1
Fa3 / No autumn N / -0.9 / -0.4 / -0.9 / -0.4 / n/a / n/a / n/a / n/a / n/a / n/a
Fa5 / Account for manure / 5.1 / 15.3 / n/a / n/a / 1.5 / 1.9 / n/a / n/a / 0.7 / 1.7
Fa2 Fa5 / Fa5, then decrease N by 20% / 1.2 / -0.8 / n/a / n/a / 1.2 / 1.3 / n/a / n/a / 0 / 0
M1 / Manure timing / -6.7 / -3 / n/a / n/a / -7.2 / -7.2 / n/a / n/a / n/a / n/a
M2 / Manure timing / -5.5 / -2.8 / n/a / n/a / -3.1 / -3.1 / n/a / n/a / n/a / n/a
M1 M5 / Plus account for manure / -4.3 / -2 / n/a / n/a / -2.9 / -2.9 / n/a / n/a / 0.7 / 1.7
M2 M6 / Plus account for manure / -3.6 / -1.9 / n/a / n/a / -1.5 / -1.5 / n/a / n/a / n/a / n/a
AP2 / Reduce pig numbers / n/a / n/a / n/a / n/a / n/a / n/a / n/a / n/a / -3.6 / -3.6

1

Cost curve of nitrate mitigation options NT2511

Comparison of effectiveness and cost of measures applied to the sandy soil rotation (without manure)

Comparison of effectiveness and cost of measures applied to the sandy soil rotation (with outdoor pigs)

Comparison of effectiveness and cost of measures applied to the clay soil rotation with manure (dry climate)

Comparison of effectiveness and cost of measures applied to the clay soil rotation with manure (wet climate)

Comparison of effectiveness and cost of measures applied to the clay soil rotation without manure (dry climate)

Comparison of effectiveness and cost of measures applied to the clay soil rotation without manure (wet climate)

Cost curve of mitigation options for sandy soil rotation without manure

Cost curve of mitigation options for sandy soil rotation with outdoor pigs

Cost curve of mitigation options for clay soil rotation with manure (dry climate)

Cost curve of mitigation options for clay soil rotation with manure (wet climate)

Cost curve of mitigation options for clay soil rotation without manure (dry climate)

Cost curve of mitigation options for clay soil rotation without manure (wet climate)

1

Cost curve of nitrate mitigation options NT2511