WOLFRAM SYSTEM MODELER
Arable_Land_DynamicsArable land dynamics |
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Diagram
Wolfram Language
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SystemModel["SystemDynamics.WorldDynamics.World3.Arable_Land_Dynamics"]
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Information
This model quantifies the land that is being used to produce food, i.e., the arable land. The model contains three state variables, representing the potential arable land, i.e., land that could be developed to grow crop, but so far hasn't been developed; the arable land that is currently being used for agriculture; and finally, the land that is being used for urban development and industry (including mining). Some of the potential arable land is getting developed over time, whereas some of the arable land is being lost either to urban development or to erosion.
The arable land is measured in units of hectares.
Parameters (9)
| arable_land_init |
Value: 900000000.0 Type: Real (hectare) Description: Initial arable land |
|---|---|
| avg_life_land_norm |
Value: 1000 Type: Real (yr) Description: Normal life span of land |
| inherent_land_fert |
Value: 600 Type: Real (kg/(hectare.yr)) Description: Inherent land fertility |
| pot_arable_land_init |
Value: 2300000000.0 Type: Real (hectare) Description: Initial potential arable land |
| pot_arable_land_tot |
Value: 3200000000.0 Type: Real (hectare) Description: Total potential arable land |
| social_discount |
Value: 0.07000000000000001 Type: Real (1/yr) Description: Social discount |
| t_land_life_time |
Value: 4000 Type: Real (yr) Description: Land life time |
| urban_ind_land_init |
Value: 8200000.0 Type: Real (hectare) Description: Initial urban and industrial land |
| urb_ind_land_dev_time |
Value: 10 Type: Real (yr) Description: Urban and industrial land development time |
Connectors (8)
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land_yield |
Type: MassInPort Description: Land yield |
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marg_prod_agr_inp |
Type: MassInPort Description: Development of marginally producing land |
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population |
Type: MassInPort Description: Population |
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ind_out_pc |
Type: MassInPort Description: Per capita annual industrial output |
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tot_agric_invest |
Type: MassInPort Description: Total investment in the agricultural sector |
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arable_land |
Type: MassOutPort Description: Arable land |
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urban_ind_land |
Type: MassOutPort Description: Land occupied by human dwellings and industry |
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fr_inp_al_land_dev |
Type: MassOutPort Description: Fraction of capital invested in agriculture allocated to the devlopment of arable land |
Components (23)
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Land_Devel_Rt |
Type: RRate Description: p.289 of Dynamics of Growth in a Finite World |
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Arable_Land |
Type: Level2b Description: p.279 of Dynamics of Growth in a Finite World |
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Land_Rem_Urb_Ind_Use |
Type: RRate Description: p.322 of Dynamics of Growth in a Finite World |
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Land_Erosion_Rt |
Type: RRate Description: p.318 of Dynamics of Growth in a Finite World |
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sink |
Type: Sink Description: This is the (dummy) sink model of System Dynamics |
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Pot_Arable_Land |
Type: Level1b Description: p.279 of Dynamics of Growth in a Finite World |
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Urban_Ind_Land |
Type: Level1a Description: p.322 of Dynamics of Growth in a Finite World |
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Land_Dev_Rt |
Type: Land_Devel_Rt Description: p.289 of Dynamics of Growth in a Finite World |
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Land_Rem_UI_Use |
Type: Land_Rem_Urb_Ind_Use Description: p.322 of Dynamics of Growth in a Finite World |
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Land_Er_Rt |
Type: Division Description: p.318 of Dynamics of Growth in a Finite World |
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Avg_Life_Land |
Type: Gain Description: p.316 of Dynamics of Growth in a Finite World |
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Dev_Cost_Per_Hect |
Type: Tabular Description: p.291 of Dynamics of Growth in a Finite World |
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Gain1 |
Type: Gain Description: p.291 of Dynamics of Growth in a Finite World |
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Marg_Prod_Land_Dev |
Type: Marg_Prod_Land_Dev Description: p.312 of Dynamics of Growth in a Finite World |
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Fr_Inp_Al_Land_Dev |
Type: Tabular Description: p.311 of Dynamics of Growth in a Finite World |
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Div1 |
Type: Division Description: p.311 of Dynamics of Growth in a Finite World |
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Land_Fr_Cult |
Type: Gain Description: p.278 of Dynamics of Growth in a Finite World |
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Urb_Ind_Land_Req |
Type: Prod_2 Description: p.321 of Dynamics of Growth in a Finite World |
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Urb_Ind_Land_PC |
Type: Tabular Description: p.321 of Dynamics of Growth in a Finite World |
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S_Land_Life_Mlt_Yield |
Type: S_Land_Life_Mlt_Yield Description: p.317 of Dynamics of Growth in a Finite World |
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P_Land_Life_Mlt_Yield_1 |
Type: Tabular Description: p.317 of Dynamics of Growth in a Finite World |
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P_Land_Life_Mlt_Yield_2 |
Type: Tabular Description: p.318 of Dynamics of Growth in a Finite World |
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Gain2 |
Type: Gain Description: p.317 of Dynamics of Growth in a Finite World |
Used in Examples (11)
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SystemDynamics.WorldDynamics.World3 Original WORLD3 model |
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SystemDynamics.WorldDynamics.World3 More abundant non-recoverable natural resources |
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SystemDynamics.WorldDynamics.World3 More accessible non-recoverable natural resources and pollution control |
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SystemDynamics.WorldDynamics.World3 More accessible non-recoverable natural resources, pollution control, and land yield enhancement |
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SystemDynamics.WorldDynamics.World3 More accessible non-recoverable natural resources, pollution control, land yield enhancement, and erosion protection |
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SystemDynamics.WorldDynamics.World3 More accessible non-recoverable natural resources, pollution control, land yield enhancement, erosion protection, and resource efficiency |
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SystemDynamics.WorldDynamics.World3 More abundant non-recoverable natural resources and birth control |
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SystemDynamics.WorldDynamics.World3 More abundant non-recoverable natural resources, birth control, and stable industrial output |
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SystemDynamics.WorldDynamics.World3 Combining the measures of Scenarios #6 and #8 |
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SystemDynamics.WorldDynamics.World3 Influencing the future 20 years earlier |
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SystemDynamics.WorldDynamics.World3 Influencing the future 10 years later |