spatial planning of agricultural production under environmental risks and uncertainties g. fischer,...
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Spatial Planning of Agricultural Production
under Environmental Risks and Uncertainties
G. Fischer, T. Ermolieva
International Institute for Applied Systems Analysis, Laxenburg, Austria
CwU 2007 December 10-12, 2007
IIASA, Laxenburg Austria
This research is under the umbrella of two EU-sponsored projects
CHINAGRO: Decision Support System for China's Agricultural Sustainable Development (EU-ICA4-CT-2001-10085), 2002-2005.
CATSEI: Chinese Agricultural Transition: Trade, Social and Environmental Impact (EU FP6 Project 44255), 2007-2009.
BackgroundBackground
Broad range of factors determining spatio-temporal heterogeneity of demand
and supply of agricultural products:
• Demographic change
• Urbanization
• Overall economic growth
• Availability of farmland; irrigated land
• Technological progress in agriculture
• Trade policies
• Conditions on international markets
Research questionResearch question
Growing demands for meat, intensification trends, concentration
of production according to “increasing returns” principle.
Main risks:
- environmental pollution (manure combined with chemical fertilizers) - livestock related diseases and epidemics - market risks - demand uncertainties and instabilities
A continuation of current intensification trend would bring in high risks for the future.
Risk perspective suggests rationales for spatial diversification
and co-existence of large- and small-scale producers.
Long-term planning needs to base on sustainability principles:
increasing returns in combination with enforced policies relying
on risk indicators.
Co-existence of heterogeneous producers:Co-existence of heterogeneous producers:a risk-hedging strategya risk-hedging strategy
Absence of risks: Two producers with production costs c1 < c2 < b
dxaxa 2211
Risk exposure: a1 and a2 are random variables (shocks to production)
2211 xcxc
dx *1 0*
2 x
dxx 21 01 x 02 x
2211 xcxc
},0max{)( 22112211 xaxadbExcxcxF
where bE max{0, d – a1x1 – a2x2} is the expected import cost if demand
exceeds the supply.
minimize
solution
minimize
minimize
Ermoliev, Y., Wets, R. (Eds.) Numerical Techniques for Stochastic Optimization.Computational Mathematics, Springer Verlag, Berlin, 1988.
of the distribution function describing
contingencies of the Producer 1, i.e., a1 , and the ratio c2 / b.
Optimal production share of Producer 2 is defined by the quantile
The cost efficient producer 1 is active if: c1 – bEa1 < 0
The less-efficient producer 2 stabilizes the aggregate production and the market in the presence of contingencies affecting the “most cost-effective” producer 1.
Market share of the Producer 2 (risk-free producer with higher production costs):
][),( 21222xxadbPcxxFx
0*2 x
bcxxadP /][ 2*2
*11
Take derivative
If Producer 1 is at risk: 0 < E a1 < 1, a2 = 1. Positive optimal decisions exist if:
0)0,0(1
xF 0)0,0(2
xF 11)0,0(1
bEacFx bcFx 2)0,0(2
i.e., less efficient producer 2 is active unconditionally: c2 – b < 0
Co-existence of heterogeneous producersCo-existence of heterogeneous producers
ChallengesChallenges of spatial livestock production of spatial livestock production planning under risks and uncertaintiesplanning under risks and uncertainties
Long horizons of problems related to production and risks. Spatially explicit framework: 2434 counties. Aggregate or insufficient data for estimation of spatially
“disperse” agricultural risks, indicators and constraints;
compound risks. Need for spatially-explicit stochastic LS production planning
model and data upscaling/downscaling, harmonization
procedures. Production allocation and intensification levels are projected from the base year for: - Pigs, poultry, sheep, goat, meat cattle, milk cows) and - Management system (grazing, industrial, specialized, traditional.
IIASA model for livestock production planning IIASA model for livestock production planning
Model structure and inputs
Base year distribution of production activities/resources at county level Alternative demographic projections and Economic scenarios Model derives estimates of:
- Demand for cereals and livestock products
- Spatial allocation and intensity levels of crop and livestock production;
- Environmental pressure from agricultural production
- Health and environmental risk indicators
Incorporates/compares:
Alternative production allocation criteria;
Procedures: Rebalancing/dowscaling & stochastic optimization
Livestock production allocation under Livestock production allocation under risks and uncertaintiesrisks and uncertainties
id is the expected national supply increase in the livestock product i
ijlx is the unknown portion of the supply increase i related to location j and
management system l In its simplest form, the problem is to find ijlx satisfying the following system
of equations:
ijlijl dx
,, (1)
0ijlx , (2)
jliijl bx , Ll :1 , nj :1 , mi :1 , (3)
where jlb is aggregate risk constraint restricting the expansion of production
in system l and location j .
Apart from jlb , there may be additional limits imposed on ijlx , ijlijl rx ,
which can be associated with legislation, for example, to restrict production i within a production “belt”, or to exclude from urban or protected areas, etc. Thresholds jlb and ijlr may either indicate that livestock in excess of these
values is strictly prohibited or it incurs measures such as taxes or premiums, for eradication of the risks, say, livestock diseases outbreaks or environmental pollution. In this sense, they are analogous to the risk constraints from the catastrophe and insurance theory. Values jlb and ijlr may be reasonably
treated in priors.
Sequential rebalancing procedure Sequential rebalancing procedure
iikik dqy 0- expected initial allocation of demand to location i and system k
i ikkk yb 00 /Derive relative imbalance and update000kikik yz
ki
byik
0But may not satisfy the constraint0iky
0ikz may not satisfy the constraint ik ik dz 0
k ikii zd 00 /Calculate and update 001iikik zy
siky i
kik
sik dqy can be represented as
jskik
skik
sik qqq 11 /
ik
ik dy
0ikyki
ik by
1k ikq - prior, reflects alternative “behavioral” allocation principles
Demand for product i; production in location k
Aggregate constraint on meat production at location k
by applying sequentially adjusted : , 1sikq
iskik
skik
sik qqq /1
The procedure can be viewed as a redistribution of required supply increase di
ikik qq 0e.g., by using a Bayesian type of rule for updating the prior distribution, .
The procedure converges to the optimal solution maximizing
the cross-entropy function ij
ijij q
yy ln
Fischer, G., Ermolieva, T., Ermoliev, Y., and van Velthuizen, H.,“Sequential downscaling methods for Estimation from Aggregate Data”In K. Marti, Y. Ermoliev, M. Makovskii, G. Pflug (Eds.)Coping with Uncertainty: Modeling and Policy Issue, Springer Verlag, Berlin, New York, 2006.
Bregman, L.M. “Proof of the Convergence of Sheleikhovskii’s Method for a Problem with Transportation Constraints”, Journal of Computational Mathematics and Mathematical Physics,Vol. 7, No. 1, pp191-204, 1967 (Zhournal Vychislitel’noi Matematiki, USSR, Leningrad, 1967).
For Hitchcock-Koopmans transportation model the proof is in:
For more general constraints and using duality theorem the proof is in:
Sequential rebalancing procedure Sequential rebalancing procedure
Alternative production allocation scenariosAlternative production allocation scenarios
2. Sustainable Scenario: trade-off between development and risks.
1. Demand Driven Scenario: Production increase in locations is proportional to demand potential (people, rural/urban, income)
Economic, social, environmental risk and sustainability indicators and constraints reflect location-specific conditions and limitations such as water and land scarcity, livestock density, urbanization level.
Allocation of livestock beyond specified constraints may lead to disastrous consequences related to water and air pollution, hazards of livestock disease outbreaks, threats to human health, which may incur high costs.
The indicators and constraints are treated within priors or as explicit constraints/goals. Individual “weights” of indicators/constraints reflect the critical trade- offs, limitations and goals in locations.
0 (%)
3-5 (%)
6-10 (%)
11-15 (%)
16-20 (%)
21-25 (%)
26-30 (%)
31-35 (%)
36-40 (%)
41-45 (%)
46-50 (%)
51-55 (%)
56-60 (%)
61-65 (%)
66-70 (%)
71-75 (%)
76-80 (%)
81-85 (%)
86-90 (%)
91-95 (%)
96-100 (%)
Resource Constraints: Resource Constraints: Intensity of cultivated and orchard land Intensity of cultivated and orchard land
(percent of total land in county) in 2000.(percent of total land in county) in 2000.
Population distributionPopulation distribution(persons per square kilometer)(persons per square kilometer)
Rural
Urban
0
20000
40000
60000
80000
100000
2000 2005 2010 2015 2020 2025 2030
1000
mt
Other meat
Pork
Poultry
0
20000
40000
60000
80000
100000
2000 2005 2010 2015 2020 2025 2030
10
00 m
t
0.0
0.2
0.4
0.6
0.8
1.0
1.2
6 7 8 9 10
log(Income)
Inco
me E
lasti
cit
yMeat demand by income
0
100
200
300
400
500
600
2000 2005 2010 2015 2020 2025 2030
Mil
lio
ns
Large
Spec
Trad
Pigs by type of production system Meat demand by type
Meat demand by sector
01-150151-300301-600601-10001001-1500>1500
01-150151-300301-600601-10001001-1500>1500
2030
Hot-spots of high intensity of confined livestock(livestock biomass in kg/ha cultivated land)
2000
0
1-25
26-50
51-100
101-150
>150
2000
a.
01-2526-5051-100101-150>150
44: Guandong
33: Zhejiang
0
1-25
26-50
51-100
101-150
>150
Hot-spots of manure nutrients from confined livestock, (kg nitrogen/ha cultivated land), year
2000:2030: a. Demand-drivingb. Risk-adjusted
01-5051-150151-250251-350351-500>500
01-5051-150151-250251-350351-500>500
Hot spots of fertilizer consumption (kg nitrogen/ha cultivated land)
2030
2000
Nutrient balance calculations.
County-specific nutrient balances compare nutrients from livestockmanure and fertilizers with the requirements and uptake capacities of crops.
Thus, calculated total nutrients losses include:
nutrient losses from livestock housing, from manure storage facilities as well as total liquid manure (largely unused),
losses stemming from non-effective manure and fertilizers,
losses due to over-supply of nutrients from fertilizers and manure to crops,
non-effective manure nutrients produced by pastoral livestock systems.
Nutrient (nitrogen) losses per unit Nutrient (nitrogen) losses per unit area, kg/haarea, kg/ha
0
1-25
26-50
51-100
101-150
151-250
>250
2000
0
1-25
26-50
51-100
101-150
151-250
>250
2030
A B
0
400
800
1200
1600
2000
2400
1-25 26-50 51-100 101-150 151-250 >250
Intensity of nitrogen losses per unit land (kg/ha)
Nu
mb
er o
f co
un
ties
0%
20%
40%
60%
80%
100%
Per
cen
tag
e o
f co
un
ties
Frequency distribution of:Frequency distribution of:a. Number of counties, anda. Number of counties, and
b. Population, with regard to the intensityb. Population, with regard to the intensityof nitrogen losses per unit of landof nitrogen losses per unit of land area. area.
0%
20%
40%
60%
80%
100%
1-25 26-50 51-100 101-150 151-250 >250
Intensity of nitrogen losses per unit land (kg/ha)
Per
cen
tag
e o
f p
op
ula
tio
n
0%
20%
40%
60%
80%
100%
Cu
mu
lati
ve p
erce
nta
ge
of
po
pu
lati
on
0.0 0.2 0.4 0.6 0.8 1.0
N
NE
E
C
S
SW
NW
0.0 0.2 0.4 0.6 0.8 1.0
N
NE
E
C
S
SW
NW
Figure 3. Relative distribution of population according to classes of severity of environmental pressure from livestock, 2030: (a) demand driven scenario, (b) environmentally friendly scenario.
Two scenarios are compared with respect to Two scenarios are compared with respect to number of people in China’s regions exposed to number of people in China’s regions exposed to
different categories of environmental risksdifferent categories of environmental risks