An agriculturalist’s Operational Research perspective

Daniel Sandars; BSc(Hons.), 2xMSc, AFORS, MIAgrM:CEnv

6th February 2015

Climax vegetation?

OR Prescriptive or Predictive?

Complex systems theory

Linear Programme SFarmModThe case of 12 novel fibre crops

Environmental QuantificationThe LCA Concept

The Environment

ProductionSystem

Functional Unit

Natural Resources

Manufactured Inputs

Emissions & wastes

Boundarye.g. 1 kg Pig carcass or

1 kg bread wheat

e.g. ammonia, carbon dioxide

e.g. fertiliser, machinery, structures

e.g. minerals, fossil energy, land

Co-products, e.g. straw, manure

Cradle to grave is fullest application of LCA

Production

Processing

Distribution

Consumption / use

Disposal

Each step has is own set of inputs and outputs, like the production stage

Farm gate

globalwarming

ozone depletion

N2O, CH4

acidification

drainageNutrientOverload

Metals NO3-

Runoff

BOD, PO43+

deposition

ammonia

pathogensodours

Best environmental options?

Slurry tankers

Standard splash-plate spreader

Over-the-fence broadcast spreader

Low trajectory splash-plate

spreader

Trailing pipe/shoe Sub-soil shallow injection spreader

Slurry stores

Holsworthy Centralised Anaerobic Digester

Controlling the N

-0.020

-0.015

-0.010

-0.005

0.000

0.005

0.010

0.015

0.020

0% 10% 20% 30% 40% 50% 60% 70% 80% 90%

Abatement of digestate NH3 landspreading losses

t/kt

Weste

rn E

uro

pean

Im

pacts

Global Warming Normal

Acidification Normal

Eutrophication Normal

Fig. 6.6 LCA predictions of the overall effects abating ammonia losses from land spreading of

digestate on Global Warming, Acidification and Eutrophication, each normalised with respect to current Western European environmental emissions inventory (Anon, 2005)

Where does Agric. OR fit in?

EA 300502/ ./17

Detailed process modelling

Macro-economics

Complex system and decision system models

Day

AnimalPlant

HerdCrop

RegionFarm EuropeNation

Year

Month

Week

Decade

Control

Tactical

PolicyStrategic

Agricultural Operational Research Ecosystem

Additional resources

• Plà, L.M., Sandars, D.L., Higgins, A.J. A perspective on operational research prospects for agriculture (2014) Journal of the Operational Research Society, 65 (7), pp. 1078-1089. http://www.palgrave-journals.com/jors/journal/v65/n7/abs/jors201345a.html

• Audsley, E., Sandars, D.L. A review of the practice and achievements from 50 years of applying OR to agricultural systems in Britain OR Insight (2009) 22, 2–18. doi:10.1057/ori.2008.1 http://www.palgrave-journals.com/ori/journal/v22/n1/full/ori20081a.html

• Linear programming– Dantzig, George B. (1990). "The Diet Problem". Interfaces 20 (4):

43–7. doi:10.1287/inte.20.4.43 http://resources.mpi-inf.mpg.de/departments/d1/teaching/ws14/Ideen-der-Informatik/Dantzig-Diet.pdf

Soils and Weather

Workable hours

Profitability (or loss)

Crop and livestock outputs

Environmental Impacts

Possible crops, yields, maturity dates, sowing dates

Silsoe Whole Farm ModelLinear programme, important features timeliness penalties, rotational penalties, workability per task, uncertainty

Machines and people

Constraints and penalties

Heavy clay, 800 mm annual rainfall

0

50

100

150

200

250

Ho

urs

Sandy loam, 500 mm annual rainfall

-

50

100

150

200

250

Ho

urs

Workable hours v. tractor hours

Period, fortnights Period, fortnights

Low gross margin crop

(Sown spring, harvested September)

£370/ha versus £600-750/ha

Crop X

WRape

SBarley

WBarley

WWheat

Nitrate leaching scenarios on an arable sandy loam farm: crop areas; profit; N leaching and N use

Profit = £456/ha

N leach = 56.4 kg/ha

N use = 123.7 kg/ha

£430/ha

55.7 kg/ha

100 kg/ha

£433/ha

44.9 kg/ha

168.5 kg/ha

• N restricting policy increases Nitrate leaching - more spring crops increasing over-winter leaching• To decrease N leaching, grow crops which use the N applied efficiently

Base N < 100kg/ha Opt Profit + N leach WW

WB

SB

WR

WBn

RS

Pots

SBt

Peas

SR

SBn

More legumes. No Oilseed rape

No legumes. No Oilseed rape

Urban Crop yields

Forestry

Flooding

Rural land allocation

Hydrology

Biodiversity

Pests & diseases

Water use

Snow cover

Water availability

Climate & socio-economic scenarios

Climsave: Nordic area