1. LUCIA (Marohn and Cadisch 2011) simulates the consequences of land use and
the management of natural resources on a daily basis, such as soil erosion and
degradation, changes in soil fertility and productivity. Soil organic matter, as
well as plant growth, is mechanistically simulated by the model. Land use
change in LUCIA at its present stage is defined a priori, that is, land use maps
need to be generated in advance for every year of the simulation. Dynamic
reactions in land use and management to developments, such as changed land
suitability for specific crops, are not considered.
2. MP-MAS (Sect. 10.6 and 10.7) is focused on the decisions made by agents, e.g.,
regarding land use and fertilizer inputs, driven by income optimization at the
farm level. Potential crop growth and soil fertility, as criteria for decisionmaking are considered on an annual time step by the in-built balance-based
Tropical Soil Productivity Calculator (TSPC; Aune and Lal 1995;
Schreinemachers et al. 2007). The model does not keep track of changes in
soil fertility throughout the year.
Both models, LUCIA and MP-MAS, are thus highly complementary, and while
land use decisions are exogenous to LUCIA, they are endogenous to MP-MAS. On
the other hand, LUCIA has increased accuracy in terms of soil fertility and crop
growth over MP-MAS, as it introduces a process-based element which replaces the
less mechanistic TSPC. The coupled package developed here accounted for biophysical processes at the pixel scale and used a daily time step, including soil
organic matter dynamics and the routing of flows in the landscape. At the same
time, it accounted for dynamic land use change in response to changing biophysical
and socio-economic conditions.
This paper makes reference to several other studies that have reported on use of
the standalone versions of LUCIA (Sect 10.2), and MP-MAS (Sect. 10.6 and
Sect 10.7), as well as of the coupled model system (Marohn et al. in press). For
methods and literature used, please refer to these publications.
10.8.2 Methods
10.8.2.1 Coupling Approach
This section will focus on those aspects related to the coupling process. Figure 10.21
shows the coupling and complementary nature of the two models. Decisions on
investments and production are made yearly in MP-MAS, based on the available
resources and expected yields, while decisions regarding land use and management
directly influence crop growth, which is calculated in LUCIA at a daily resolution.
Crop yields generated in LUCIA, in turn, form part of the farm income and thus the
resources that can be spent in MP-MAS during the next production cycle.
Technically, the two models are not rigidly linked, but exchange data via Typed
Data Transfer (TDT; Linstead 2004), a software protocol that allows one to run both
10 Integrated Modeling of Agricultural Systems in Mountainous Areas
419
the management of natural resources on a daily basis, such as soil erosion and
degradation, changes in soil fertility and productivity. Soil organic matter, as
well as plant growth, is mechanistically simulated by the model. Land use
change in LUCIA at its present stage is defined a priori, that is, land use maps
need to be generated in advance for every year of the simulation. Dynamic
reactions in land use and management to developments, such as changed land
suitability for specific crops, are not considered.
2. MP-MAS (Sect. 10.6 and 10.7) is focused on the decisions made by agents, e.g.,
regarding land use and fertilizer inputs, driven by income optimization at the
farm level. Potential crop growth and soil fertility, as criteria for decisionmaking are considered on an annual time step by the in-built balance-based
Tropical Soil Productivity Calculator (TSPC; Aune and Lal 1995;
Schreinemachers et al. 2007). The model does not keep track of changes in
soil fertility throughout the year.
Both models, LUCIA and MP-MAS, are thus highly complementary, and while
land use decisions are exogenous to LUCIA, they are endogenous to MP-MAS. On
the other hand, LUCIA has increased accuracy in terms of soil fertility and crop
growth over MP-MAS, as it introduces a process-based element which replaces the
less mechanistic TSPC. The coupled package developed here accounted for biophysical processes at the pixel scale and used a daily time step, including soil
organic matter dynamics and the routing of flows in the landscape. At the same
time, it accounted for dynamic land use change in response to changing biophysical
and socio-economic conditions.
This paper makes reference to several other studies that have reported on use of
the standalone versions of LUCIA (Sect 10.2), and MP-MAS (Sect. 10.6 and
Sect 10.7), as well as of the coupled model system (Marohn et al. in press). For
methods and literature used, please refer to these publications.
10.8.2 Methods
10.8.2.1 Coupling Approach
This section will focus on those aspects related to the coupling process. Figure 10.21
shows the coupling and complementary nature of the two models. Decisions on
investments and production are made yearly in MP-MAS, based on the available
resources and expected yields, while decisions regarding land use and management
directly influence crop growth, which is calculated in LUCIA at a daily resolution.
Crop yields generated in LUCIA, in turn, form part of the farm income and thus the
resources that can be spent in MP-MAS during the next production cycle.
Technically, the two models are not rigidly linked, but exchange data via Typed
Data Transfer (TDT; Linstead 2004), a software protocol that allows one to run both
10 Integrated Modeling of Agricultural Systems in Mountainous Areas
419