2023-03-21
\[H'=-\sum _{i=1}^{R}p_{i}\ln p_{i}\]
set Cells; # vertex set of the spacial graph set Species; # Names of Species in the problem set Landuses; # Name of possible Landuses param SpeciesSuitabilityLanduse {Species, Landuses,Cells} ; #suitability for each species in each cell in each Landuses param TransitionCost {Cells, Landuses}; # Cost of transforming a cell to this landuse param b; #budget var LanduseDecision {c in Cells,l in Landuses} binary; # decision on which landuse to use for cell Cell minimize InvShanonDiv{s in Species}: (sum{c in Cells, l in Landuses} LanduseDecision[c,l]*SpeciesSuitabilityLanduse[s,l,c]/ sum{t in Species, d in Cells, m in Landuses} LanduseDecision[d,m]*SpeciesSuitabilityLanduse[t,m,d])* log(sum{c in Cells, l in Landuses} LanduseDecision[c,l]*SpeciesSuitabilityLanduse[s,l,c]/ sum{t in Species, d in Cells, m in Landuses} LanduseDecision[d,m]*SpeciesSuitabilityLanduse[t,m,d]); subj to PropotionalUse{c in Cells}: sum{l in Landuses} LanduseDecision[c,l] = 1; subj to Budget: sum{c in Cells, l in Landuses} LanduseDecision[c,l]*TransitionCost[c,l] <= b;
Given a set of spatial cells \(c\), a set of species \(s\), and a set of land uses \(l\), we have:
A parameter for species suitability land use \(SSL_{s,c,l}\), representing the suitability of a given land use \(l\) in cell \(c\) for species \(s\).
A parameter for transition cost \(TransitionCost_{c,l}\), representing the cost of transforming a cell \(c\) to a land use \(l\).
A budget constraint \(b\).
where \(p_s\) is defined as:
\[p_s = \frac{\sum_{c \in C} \sum_{l \in L} SSL_{s,c,l} \cdot LandUseDecision_{c,l}}{\sum_{t \in S} \sum_{d \in C} \sum_{m \in L} SSL_{t,d,m} \cdot LandUseDecision_{d,m}}\]
We want to determine which land use should be assigned to each cell in order to minimize the inverse Shannon diversity index. Formally, we have:
\[\min \sum_{s \in S} p_s \log(p_s)\]
The decision variable \(LandUseDecision_{c,l}\) is a binary variable that indicates whether cell \(c\) is assigned to land use \(l\):
\[LandUseDecision_{c,l} \in {0,1}\]
Subject to the following constraints:
PropotionalUse: each cell must use exactly one landuse
Budget: the total cost of land use change must be within the budget limit