MAgPIE - An Open Source land-use modeling framework

4.8.2

created with goxygen 1.4.4

Livestock (70_livestock)

Description

The livestock module calculates how much and what kind of biomass is required as feed to produce livestock food commodities.

For this purpose, the livestock module provides for every time-step regional and product-specific feed baskets that determine type and magnitude of feed needed to produce one unit of livestock commodities. Estimated pasture feed demand is also relevant for the module 31_past in order to derive required pasture areas. The information flow between the livestock and the pasture module is organized via interfaces vm_dem_feed, vm_supply and vm_prod_reg via modules 16_demand and 21_trade. Feed demand estimates are also required for the modules 53_methane and 55_awms. Additionally, the livestock module provides production costs for livestock commodities.

Interfaces

Interfaces to other modules

Input

module inputs (A: fbask_jan16 | B: fbask_jan16_sticky)
  Description Unit A B
fm_attributes
(attributes, kall)
Conversion factors - where X is ton N P K C DM WM or PJ GE \(X/tDM\) x x
fm_nutrition_attributes
(t_all, kall, nutrition)
Nutrition attributes of food items dedicated for fooduse \(10^6 kcal/tDM | t Protein/tDM\) x x
im_gdp_pc_ppp_iso
(t_all, iso)
Per capita income in purchasing power parity \(USD_{05PPP}/cap/yr\) x x
im_pop
(t_all, i)
Population \(10^6/yr\) x x
im_pop_iso
(t_all, iso)
Population \(10^6/yr\) x x
pm_hourly_costs
(t, i, wage_scen)
Hourly labor costs in agriculture on regional level before and after including wage scenario \(USD_{MER}05/hour\) x x
pm_interest
(t_all, i)
Interest rate in each region and timestep \(\%/yr\) x
pm_kcal_pc_initial
(t, i, kall)
Per capita consumption in food demand model before price shock \(kcal/capita/day\) x x
pm_productivity_gain_from_wages
(t, i)
Multiplicative factor describing productivity gain related to higher wages \(1\) x x
sm_fix_SSP2 year until which all parameters are fixed to SSP2 values \(year\) x x
vm_prod_reg
(i, kall)
Regional aggregated production \(10^6 tDM/yr\) x x

Output

module outputs
  Description Unit
fm_feed_balanceflow
(t_all, i, kap, kall)
Balanceflow balance difference between estimated feed baskets and FAO \(10^6 tDM\)
im_feed_baskets
(t_all, i, kap, kall)
Feed baskets in tDM per tDM livestock product \(1\)
im_slaughter_feed_share
(t_all, i, kap, attributes)
Share of feed that is incorporated in animal biomass \(1\)
pm_past_mngmnt_factor
(t, i)
Regional pasture management intensification factor \(1\)
vm_cost_prod_fish
(i)
Fish factor costs \(10^6 USD_{05MER}/yr\)
vm_cost_prod_livst
(i, factors)
Livestock factor costs \(10^6 USD_{05MER}/yr\)
vm_dem_feed
(i, kap, kall)
Regional feed demand including byproducts \(10^6 tDM/yr\)

Realizations

(A) fbask_jan16

The fbask_jan16 realization of the livestock module is based on the methodology as described in Weindl, Bodirsky, et al. (2017) and Weindl, Popp, et al. (2017). An important part of the feed demand calculations is conducted outside of the core MAgPIE-GAMS code. Livestock products (ruminant meat, whole-milk, pork, poultry meat and eggs) are supplied by five animal food systems (beef cattle, dairy cattle, pigs, broilers and laying hens). The parameterization of the livestock sector in the initial year is consistent with FAO statistics regarding livestock production, livestock productivity and concentrate feed use. The fbask_jan16 realization requires regional and product-specific feed baskets that are calculated by a set of preprocessing routines outside of the MAgPIE-GAMS code. Following the methodology of Wirsenius (2000), feed conversion (total feed input per product output in dry matter) and feed baskets (demand for different feed types per product output in dry matter) are derived by compiling system-specific feed energy balances. For the establishment of these balances, we apply feed energy requirements per output, as estimated by wirsenius_human_2000 for each animal function and animal food system. These estimates are based on standardized bio-energetic equations and include the minimum energy requirements for maintenance, growth, lactation, reproduction and other basic biological functions of the animals. Moreover, they comprise a general allowance for basic activity and temperature effects. By distributing the available feed at country level to animal food systems according to their feed energy demand and dividing resulting dry matter feed use by the production volume of the respective systems, we obtain both estimates for feed conversion and feed baskets across different animal food systems and countries. To facilitate projections of feed conversion and feed baskets, we create regression models with livestock productivity (annual production per animal [ton fresh matter/animal/year]) as predictor, which permit the construction of livestock feeding scenarios. Currently, feeding scenarios are derived based on exogenous livestock productivity scenarios consistent with the storylines of the Shared Socioeconomic Pathways (SSPs). For beef cattle, pigs and broilers, livestock productivity is defined as meat production per animals in stock (e.g. total cattle herd) and for dairy cattle and laying hen as milk or egg production per producing animals (e.g. milk cows). A power function is used to describe the functional relation between feed conversion and livestock productivity: Relationship between feed conversion and livestock productivity (Weindl, Bodirsky, et al. 2017). In the case of feed composition, we use an additional proxy parameter in our analysis. What type of biomass is used to feed animals is to a certain extent influenced by universal aspects (e.g. the need for more energy-rich feed at higher productivity levels), whereas other aspects are strongly influenced by geographical location (e.g. availability and costs of permanent pasture compared to cropland feed, agro-ecological and climatic conditions that favour selected feed items; socio-cultural determinants etc.). For cattle systems the proxy (climate-zone specific factor) was determined by calculating the share of the national population living in arid and cold climate zones. Relationship between the share of crop residues, occasional feed and grazed biomass in feed baskets and livestock productivity for beef cattle systems (Weindl, Bodirsky, et al. 2017). Relationship between the share of crop residues, occasional feed and grazed biomass in feed baskets and livestock productivity for diary cattle systems (Weindl, Bodirsky, et al. 2017). These relationships between feed baskets and livestock productivity are used to construct feeding scenarios that reflect the narratives of the SSPs. The resulting feed baskets enter the MAgPIE model as scenario-dependent input data and are crucial for the feed demand calculations in the livestock module.

Demand for different feed items is derived by multiplying the regional livestock production with the respective feed baskets. Additionally, inconsistencies with the FAO inventory of national feed use in the case of crops as well as consideration of alternative feed sources that reduce e.g. the demand for grazed biomass like scavenging and roadside grazing are balanced out by the parameter fm_feed_balanceflow.

\[\begin{multline*} vm\_dem\_feed(i2,kap,kall) \geq vm\_prod\_reg(i2,kap) \cdot \sum_{ct}im\_feed\_baskets(ct,i2,kap,kall) +\sum_{ct}fm\_feed\_balanceflow(ct,i2,kap,kall) \end{multline*}\]

Factor requirement costs (e.g. labour, capital, but without costs for feed) of livestock production depend on the amount of production and the per-unit costs. For ruminant products (milk and meet), we use a regression of per-unit factor costs from the GTAP database (Narayanan and Walmsley 2008) and livestock productivity. Here, factor costs rise with intensification. The per-unit costs for non-ruminants and fish are assumed to be independent from productivity trajectories for simplification. Therefore, i70_cost_regr(i,kli,"cost_regr_b") is set to zero in the case of livestock products generated in monogastric systems. To account for increased hourly labor costs and producitivity in case of an external wage scenario, the total labor costs are scaled by the corresponding increase in hourly labor costs and the related productivity gain from 36_employment.

\[\begin{multline*} vm\_cost\_prod\_livst(i2,"labor") = \sum_{kli}\left( vm\_prod\_reg(i2,kli) \cdot \sum_{ct} i70\_fac\_req\_livst(ct,i2,kli)\right) \cdot \sum_{ct} p70\_cost\_share\_livst(ct,i2,"labor") \cdot \sum_{ct}\left( \left(\frac{1}{pm\_productivity\_gain\_from\_wages(ct,i2)}\right) \cdot \left(\frac{pm\_hourly\_costs(ct,i2,"scenario") }{ pm\_hourly\_costs(ct,i2,"baseline")}\right)\right) \end{multline*}\]

\[\begin{multline*} vm\_cost\_prod\_livst(i2,"capital") = \sum_{kli}\left( vm\_prod\_reg(i2,kli) \cdot \sum_{ct} i70\_fac\_req\_livst(ct,i2,kli)\right) \cdot \sum_{ct} p70\_cost\_share\_livst(ct,i2,"capital") \end{multline*}\]

\[\begin{multline*} vm\_cost\_prod\_fish(i2) = vm\_prod\_reg(i2,"fish") \cdot i70\_cost\_regr(i2,"fish","cost\_regr\_a") \end{multline*}\]

The fbask_jan16 realization of the livestock module also estimates an exogenous pasture management factor pm_past_mngmnt_factor that is used to scale biophysical pasture yields in the module 14_yields. The exogenous calculation of pasture management requires information on changes in the number of cattle reared to fulfil the food demand for ruminant livestock products:

p70_cattle_stock_proxy(t,i) = im_pop(t,i)*pm_kcal_pc_initial(t,i,"livst_rum")
                  /i70_livestock_productivity(t,i,"sys_beef");
p70_milk_cow_proxy(t,i) = im_pop(t,i)*pm_kcal_pc_initial(t,i,"livst_milk")
                  /i70_livestock_productivity(t,i,"sys_dairy");

The lower bound for p70_cattle_stock_proxy and p70_milk_cow_proxy is set to 20% of initial values in 1995:

p70_cattle_stock_proxy(t,i)$(p70_cattle_stock_proxy(t,i) < 0.2*p70_cattle_stock_proxy("y1995",i)) = 0.2*p70_cattle_stock_proxy("y1995",i);
p70_milk_cow_proxy(t,i)$(p70_milk_cow_proxy(t,i) < 0.2*p70_milk_cow_proxy("y1995",i)) = 0.2*p70_milk_cow_proxy("y1995",i);

The parameter p70_cattle_feed_pc_proxy is a proxy for regional daily per capita feed demand for pasture biomass driven by demand for beef and dairy products, which is later used for weighted aggregation.

p70_cattle_feed_pc_proxy(t,i,kli_rd) = pm_kcal_pc_initial(t,i,kli_rd)*im_feed_baskets(t,i,kli_rd,"pasture")/(fm_nutrition_attributes(t,kli_rd,"kcal") * 10**6);

The parameter p70_incr_cattle describes the changes in the number of cattle relative to the previous time step:

if (ord(t)>1,
   p70_incr_cattle(t,i) = ( (p70_cattle_feed_pc_proxy(t,i,"livst_rum")  + 10**(-6))* (p70_cattle_stock_proxy(t,i)/p70_cattle_stock_proxy(t-1,i))
                                          +  (p70_cattle_feed_pc_proxy(t,i,"livst_milk") + 10**(-6)) * (p70_milk_cow_proxy(t,i)/p70_milk_cow_proxy(t-1,i)) )
                                        / sum(kli_rd, p70_cattle_feed_pc_proxy(t,i,kli_rd) + 10**(-6));
else
   p70_incr_cattle(t,i) = 1;
);

The pasture management factor is calculated by applying a linear relationship that links changes in pasture management with changes in the number of cattle:

if (m_year(t) <= s70_past_mngmnt_factor_fix,
   pm_past_mngmnt_factor(t,i) = 1;
else               
   pm_past_mngmnt_factor(t,i) =   ( (s70_pyld_intercept + f70_pyld_slope_reg(i)*p70_incr_cattle(t,i)**(5/(m_year(t)-m_year(t-1))) 
           )**((m_year(t)-m_year(t-1))/5) )*pm_past_mngmnt_factor(t-1,i);
 );

Limitations Intensification of livestock production and related changes in livestock feeding are modelled exogenously. Therefore, the livestock sector does not endogenously respond to demand and climate shocks and policies, e.g. targeting climate protection.

(B) fbask_jan16_sticky

The fbask_jan16_sticky realization of the livestock module is based on the fbask_jan16 realization, and only differs from it by implementing capital stocks as introduced in the sticky_feb18 factor cost module realization.

The methodology of fbask_jan16 is described in Weindl, Bodirsky, et al. (2017) and Weindl, Popp, et al. (2017). An important part of the feed demand calculations is conducted outside of the core MAgPIE-GAMS code. Livestock products (ruminant meat, whole-milk, pork, poultry meat and eggs) are supplied by five animal food systems (beef cattle, dairy cattle, pigs, broilers and laying hens). The parameterization of the livestock sector in the initial year is consistent with FAO statistics regarding livestock production, livestock productivity and concentrate feed use. The fbask_jan16 realization requires regional and product-specific feed baskets that are calculated by a set of preprocessing routines outside of the MAgPIE-GAMS code. Following the methodology of Wirsenius (2000), feed conversion (total feed input per product output in dry matter) and feed baskets (demand for different feed types per product output in dry matter) are derived by compiling system-specific feed energy balances. For the establishment of these balances, we apply feed energy requirements per output, as estimated by wirsenius_human_2000 for each animal function and animal food system. These estimates are based on standardized bio-energetic equations and include the minimum energy requirements for maintenance, growth, lactation, reproduction and other basic biological functions of the animals. Moreover, they comprise a general allowance for basic activity and temperature effects. By distributing the available feed at country level to animal food systems according to their feed energy demand and dividing resulting dry matter feed use by the production volume of the respective systems, we obtain both estimates for feed conversion and feed baskets across different animal food systems and countries. To facilitate projections of feed conversion and feed baskets, we create regression models with livestock productivity (annual production per animal [ton fresh matter/animal/year]) as predictor, which permit the construction of livestock feeding scenarios. Currently, feeding scenarios are derived based on exogenous livestock productivity scenarios consistent with the storylines of the Shared Socioeconomic Pathways (SSPs). For beef cattle, pigs and broilers, livestock productivity is defined as meat production per animals in stock (e.g. total cattle herd) and for dairy cattle and laying hen as milk or egg production per producing animals (e.g. milk cows). A power function is used to describe the functional relation between feed conversion and livestock productivity: Relationship between feed conversion and livestock productivity (Weindl, Bodirsky, et al. 2017). In the case of feed composition, we use an additional proxy parameter in our analysis. What type of biomass is used to feed animals is to a certain extent influenced by universal aspects (e.g. the need for more energy-rich feed at higher productivity levels), whereas other aspects are strongly influenced by geographical location (e.g. availability and costs of permanent pasture compared to cropland feed, agro-ecological and climatic conditions that favour selected feed items; socio-cultural determinants etc.). For cattle systems the proxy (climate-zone specific factor) was determined by calculating the share of the national population living in arid and cold climate zones. Relationship between the share of crop residues, occasional feed and grazed biomass in feed baskets and livestock productivity for beef cattle systems (Weindl, Bodirsky, et al. 2017). Relationship between the share of crop residues, occasional feed and grazed biomass in feed baskets and livestock productivity for diary cattle systems (Weindl, Bodirsky, et al. 2017). These relationships between feed baskets and livestock productivity are used to construct feeding scenarios that reflect the narratives of the SSPs. The resulting feed baskets enter the MAgPIE model as scenario-dependent input data and are crucial for the feed demand calculations in the livestock module.

In this realization the capital share of livestock production cost does not have to be paid every timestep, but is fulfilled by having a corresponding capital stock, which mostly persists across timesteps. (See s70_depreciation_rate) This means that the production becomes cheaper in regions with higher capital shares and existing corresponding capital stocks, which makes the livestock production “stick” to some degree to existing levels. Another effect is that production increases are more likely to occur in regions of more capital intensive livestock systems with already established stocks.

The realization is based on the sticky_feb18 factor cost realization, but also differs from it in some ways. At the creation time the main differences were: 1. capital stocks are on the regional level not on cluster level 2. no differentiation of mobile and immobile capital - all capital stocks are immobile

Demand for different feed items is derived by multiplying the regional livestock production with the respective feed baskets. Additionally, inconsistencies with the FAO inventory of national feed use in the case of crops as well as consideration of alternative feed sources that reduce e.g. the demand for grazed biomass like scavenging and roadside grazing are balanced out by the parameter fm_feed_balanceflow.

\[\begin{multline*} vm\_dem\_feed(i2,kap,kall) \geq vm\_prod\_reg(i2,kap) \cdot \sum_{ct}im\_feed\_baskets(ct,i2,kap,kall) +\sum_{ct}fm\_feed\_balanceflow(ct,i2,kap,kall) \end{multline*}\]

Factor requirement costs (e.g. labour, capital, but without costs for feed) of livestock production depend on the amount of production and the per-unit costs. For ruminant products (milk and meet), we use a regression of per-unit factor costs from the GTAP database (Narayanan and Walmsley 2008) and livestock productivity. Here, factor costs rise with intensification. The per-unit costs for non-ruminants and fish are assumed to be independent from productivity trajectories for simplification. Therefore, i70_cost_regr(i,kli,"cost_regr_b") is set to zero in the case of livestock products generated in monogastric systems. To account for increased hourly labor costs and producitivity in case of an external wage scenario, the total labor costs are scaled by the corresponding increase in hourly labor costs and the related productivity gain from 36_employment.

\[\begin{multline*} vm\_cost\_prod\_livst(i2,"labor") = \sum_{kli}\left( vm\_prod\_reg(i2,kli) \cdot \sum_{ct} i70\_fac\_req\_livst(ct,i2,kli)\right) \cdot \sum_{ct} p70\_cost\_share\_livst(ct,i2,"labor") \cdot \sum_{ct}\left( \left(\frac{1}{pm\_productivity\_gain\_from\_wages(ct,i2)}\right) \cdot \left(\frac{pm\_hourly\_costs(ct,i2,"scenario") }{ pm\_hourly\_costs(ct,i2,"baseline")}\right)\right) \end{multline*}\]

\[\begin{multline*} vm\_cost\_prod\_fish(i2) = vm\_prod\_reg(i2,"fish") \cdot i70\_cost\_regr(i2,"fish","cost\_regr\_a") \end{multline*}\]

Investment costs are calculated analogously to the sticky_feb18 realization. The costs are annuitized, and corrected to make sure that the annual depreciation of the current time-step is accounted for.

\[\begin{multline*} vm\_cost\_prod\_livst(i2,"capital") = \sum_{kli}v70\_investment(i2,kli) \cdot \left(\left(1-s70\_depreciation\_rate\right) \cdot \sum_{ct}\left(\frac{pm\_interest(ct,i2)}{\left(1+pm\_interest(ct,i2)\right)}\right) + s70\_depreciation\_rate\right) \end{multline*}\]

Each livestock activity requires a certain capital stock that depends on the production. The following equations make sure that new land expansion is equipped with capital stock, and that depreciation of pre-existing capital is replaced.

\[\begin{multline*} v70\_investment(i2,kli) \geq vm\_prod\_reg(i2,kli) \cdot \sum_{ct} p70\_capital\_need(ct,i2,kli) - \sum_{ct} p70\_capital(ct,i2,kli) \end{multline*}\]

This realization of the livestock module also estimates an exogenous pasture management factor pm_past_mngmnt_factor that is used to scale biophysical pasture yields in the module 14_yields. The exogenous calculation of pasture management requires information on changes in the number of cattle reared to fulfil the food demand for ruminant livestock products:

p70_cattle_stock_proxy(t,i) = im_pop(t,i)*pm_kcal_pc_initial(t,i,"livst_rum")
                  /i70_livestock_productivity(t,i,"sys_beef");
p70_milk_cow_proxy(t,i) = im_pop(t,i)*pm_kcal_pc_initial(t,i,"livst_milk")
                  /i70_livestock_productivity(t,i,"sys_dairy");

The lower bound for p70_cattle_stock_proxy and p70_milk_cow_proxy is set to 20% of initial values in 1995:

p70_cattle_stock_proxy(t,i)$(p70_cattle_stock_proxy(t,i) < 0.2*p70_cattle_stock_proxy("y1995",i)) = 0.2*p70_cattle_stock_proxy("y1995",i);
p70_milk_cow_proxy(t,i)$(p70_milk_cow_proxy(t,i) < 0.2*p70_milk_cow_proxy("y1995",i)) = 0.2*p70_milk_cow_proxy("y1995",i);

The parameter p70_cattle_feed_pc_proxy is a proxy for regional daily per capita feed demand for pasture biomass driven by demand for beef and dairy products, which is later used for weighted aggregation.

p70_cattle_feed_pc_proxy(t,i,kli_rd) = pm_kcal_pc_initial(t,i,kli_rd)*im_feed_baskets(t,i,kli_rd,"pasture")/(fm_nutrition_attributes(t,kli_rd,"kcal") * 10**6);

The parameter p70_incr_cattle describes the changes in the number of cattle relative to the previous time step:

if (ord(t)>1,
   p70_incr_cattle(t,i) = ( (p70_cattle_feed_pc_proxy(t,i,"livst_rum")  + 10**(-6))* (p70_cattle_stock_proxy(t,i)/p70_cattle_stock_proxy(t-1,i))
                                          +  (p70_cattle_feed_pc_proxy(t,i,"livst_milk") + 10**(-6)) * (p70_milk_cow_proxy(t,i)/p70_milk_cow_proxy(t-1,i)) )
                                        / sum(kli_rd, p70_cattle_feed_pc_proxy(t,i,kli_rd) + 10**(-6));
else
   p70_incr_cattle(t,i) = 1;
);

The pasture management factor is calculated by applying a linear relationship that links changes in pasture management with changes in the number of cattle:

if (m_year(t) <= s70_past_mngmnt_factor_fix,
   pm_past_mngmnt_factor(t,i) = 1;
else               
   pm_past_mngmnt_factor(t,i) =   ( (s70_pyld_intercept + f70_pyld_slope_reg(i)*p70_incr_cattle(t,i)**(5/(m_year(t)-m_year(t-1))) 
           )**((m_year(t)-m_year(t-1))/5) )*pm_past_mngmnt_factor(t-1,i);
 );

Capital update from the last investment

Limitations Intensification of livestock production and related changes in livestock feeding are modelled exogenously. Therefore, the livestock sector does not endogenously respond to demand and climate shocks and policies, e.g. targeting climate protection.

Definitions

Objects

module-internal objects (A: fbask_jan16 | B: fbask_jan16_sticky)
  Description Unit A B
f70_cap_share_reg
(share_regr)
Parameters for regression x x
f70_cost_regr
(kap, cost_regr)
Factor requirements livestock (USD04 per tDM (A) and USD \(B)\) x x
f70_feed_baskets
(t_all, i, kap, kall, feed_scen70)
Feed baskets in tDM per tDM livestock product \(1\) x x
f70_hist_cap_share
(t_all, i)
Historical capital share x x
f70_hist_factor_costs_livst
(t_all, i, kli)
Historical factor costs in livestock production \(10^6 USD_{05MER}\) x x
f70_hist_prod_livst
(t_all, i, kli, attributes)
Historical production quantity of livestock products \(10^6 t\) x x
f70_livestock_productivity
(t_all, i, sys, feed_scen70)
Productivity indicator for livestock production \(t FM/animal\) x x
f70_pyld_slope_reg
(i)
Regional slope of linear relationship determining pasture intensification \(1\) x x
f70_slaughter_feed_share
(t_all, i, kap, attributes, feed_scen70)
Share of feed that is incorprated in animal biomass \(1\) x x
i70_cereal_scp_fadeout
(t_all, i)
Cereal feed fadeout (share 0-1) to be replaced by SCP \(1\) x x
i70_cost_regr
(i, kap, cost_regr)
Regression coefficients for livestock factor requirements \(1\) x x
i70_fac_req_livst
(t_all, i, kli)
Factor requirements \(USD_{05MER}/tDM\) x x
i70_foddr_scp_fadeout
(t_all, i)
Fodder fadeout (share 0-1) to be replaced by SCP \(1\) x x
i70_livestock_productivity
(t_all, i, sys)
Productivity indicator for livestock production \(t FM/animal/yr\) x x
p70_capital
(t, i, kli)
Preexisting immobile capital stocks before investment \(10^6 USD_{05MER}\) x
p70_capital_need
(t, i, kli)
Capital requirements per unit of output \(USD_{05MER}/ton DM\) x
p70_cattle_feed_pc_proxy
(t, i, kli_rd)
Proxy for daily per capita feed demand for pasture biomass driven by demand for beef and dairy products \(tDM/capita/day\) x x
p70_cattle_stock_proxy
(t, i)
Proxy for cattle stocks needed to fullfil food demand for ruminant meat \(10^6 animals/yr\) x x
p70_cereal_subst_fader
(t_all)
Cereal feed substitution with SCP fader \(1\) x x
p70_cost_share_calibration
(i)
Summation factor used to calibrate calculated capital shares with historical values \(1\) x x
p70_cost_share_livst
(t, i, factors)
Capital and labor shares of the regional factor costs for plant production for livestock \(1\) x x
p70_country_dummy
(iso)
Dummy parameter indicating whether country is affected by feed scenarios \(1\) x x
p70_feedscen_region_shr
(t_all, i)
Weighted share of region with regards to feed scenario of countries \(1\) x x
p70_foddr_subst_fader
(t_all)
Foddr substitution with SCP fader \(1\) x x
p70_incr_cattle
(t, i)
Change in estimated cattle stocks attributed to food demand projections \(1\) x x
p70_initial_1995_prod
(i, kli)
Initial regional production of livestock products taken from 1995 \(10^6 ton DM\) x
p70_milk_cow_proxy
(t, i)
Proxy for milk cows needed to fullfil food demand for milk \(10^6 animals/yr\) x x
q70_cost_prod_fish
(i)
Regional factor input costs for fish production x x
q70_cost_prod_liv_capital
(i)
Regional capital costs for livestock production x x
q70_cost_prod_liv_labor
(i)
Regional labor costs for livestock production x x
q70_feed
(i, kap, kall)
Regional feed demand x x
q70_investment
(i, kli)
Regional investments into farm capital x
s70_cereal_scp_substitution Cereal feed substitution with SCP share \(1\) x x
s70_depreciation_rate Yearly depreciation rate for capital stocks x
s70_feed_substitution_start Feed substitution start year x x
s70_feed_substitution_target Feed substitution target year x x
s70_foddr_scp_substitution Fodder substitution with SCP share \(1\) x x
s70_multiplicator_capital_need Multiplicator for capital need in livestock production x
s70_past_mngmnt_factor_fix Year until the pasture management factor is fixed to 1 x x
s70_pyld_intercept Intercept of linear relationship determining pasture intensification \(1\) x x
s70_subst_functional_form Switch for functional form of feed substitution scenario fader \(1\) x x
v70_investment
(i, kli)
Investment in immobile farm capital \(10^6 USD_{05MER}/yr\) x

Sets

sets in use
  description
attributes Product attributes characterizing a product (such as weight or energy content)
cost_regr Cost regression parameters
ct(t) Current time period
factors factors included in factor requirements
fadeoutscen70 Feed substitution scenarios including functional forms with targets and transition periods
feed_scen70 scenarios
i all economic regions
i_to_iso(i, iso) mapping regions to iso countries
i2(i) World regions (dynamic set)
iso list of iso countries
kall All products in the sectoral version
kap(k) Animal products
kcer70(kall) Cereals
kli_rd(kap) Ruminant meat and dairy products
kli(kap) Livestock products
nutrition Nutrition attributes
reg regression parameters for capital calculation
scen_countries70(iso) countries to be affected by selected feed sceanrio
share_regr regression parameters for capital share calculation
sys Livestock production systems
sys_meat(sys) Livestock meat production systems
sys_nonmeat(sys) Livestock non-meat production systems
sys_to_kli(sys, kli) Mapping between livestock producton systems and livestock products
t_all(t_ext) 5-year time periods
t_past(t_all) Timesteps with observed data
t(t_all) Simulated time periods
type GAMS variable attribute used for the output
wage_scen version of wages

Authors

Isabelle Weindl, Benjamin Bodirsky

See Also

09_drivers, 11_costs, 12_interest_rate, 14_yields, 15_food, 16_demand, 17_production, 36_employment, 53_methane, 55_awms, 71_disagg_lvst

References

Narayanan, G. Badri, and Eds. Walmsley Terrie L. 2008. Global Trade, Assistance, and Production: The GTAP 7 Data Base. Center for Global Trade Analysis, Purdue University. http://www.gtap.agecon.purdue.edu/databases/v7/v7_doco.asp.
Weindl, Isabelle, Benjamin Leon Bodirsky, Susanne Rolinski, Anne Biewald, Hermann Lotze-Campen, Christoph Müller, Jan Philipp Dietrich, et al. 2017. “Livestock Production and the Water Challenge of Future Food Supply: Implications of Agricultural Management and Dietary Choices.” Global Environmental Change 47 (Supplement C): 121–32. https://doi.org/10.1016/j.gloenvcha.2017.09.010.
Weindl, Isabelle, Alexander Popp, Benjamin Leon Bodirsky, Susanne Rolinski, Hermann Lotze-Campen, Anne Biewald, Florian Humpenöder, Jan Philipp Dietrich, and Miodrag Stevanovic. 2017. “Livestock and Human Use of Land: Productivity Trends and Dietary Choices as Drivers of Future Land and Carbon Dynamics.” Global and Planetary Change 159 (Supplement C): 1–10. https://doi.org/10.1016/j.gloplacha.2017.10.002.
Wirsenius, Stefan. 2000. “Human Use of Land and Organic Materials: Modeling the Turnover of Biomass in the Global Food System.” Doctoral thesis, Chalmers University of Technology. http://publications.lib.chalmers.se/publication/827-human-use-of-land-and-organic-materials-modeling-the-turnover-of-biomass-in-the-global-food-system.