338 | IAASTD Global Report

Table 5-16. Assumptions for high/low agricultural investment variants.

Parameter changes for growth rates

2050 REFERENCE RUN

2050 High AKST variant (#1)

2050 Low AKST variant (#2)

GDP growth

3.06 % per year

3.31 % per year

2.86 % per year

Livestock numbers and yield growth

Base model output numbers growth 2000-2050 Livestock: 0.74%/yr Milk: 0.29%/yr

Increase in numbers growth of animals slaughtered by 20% Increase in animal yield by 20%

Reduction in numbers growth of animals slaughtered by 20% Reduction in animal yield by 20%

Food crop yield growth

Base model output yield growth rates 2000-2050: Cereals: %/yr: 1.02 R&T: %/yr: 0.35 Soybean: %/yr 0.36 Vegetables: %/yr 0.80 Sup-tropical/tropical fruits: 0.82%/yr

Increase yield growth by 40% for cereals, R&T, soybean, vegetables, ST fruits & sugarcane, dryland crops, cotton Increase production growth of oils, meals by 40%

Reduce yield growth by 40% for cereals, R&T, soybean, vegetables, fruits & sugarcane, dryland crops, cotton Reduce production growth of oils, meals by 40%

Source: Authors.

Table 5-17. Assumptions for high/low agricultural investment combined with high/low Investment in other AKST-related factors
(irrigation, clean water, water management, rural roads, and education).

Parameter changes for growth rates

2050 BASE

2050 High AKST combined with other services (#3)

2050 Low AKST combined with other services Low (#4)

GDP growth

3.06 % per year

3.31 % per year

2.86 % per year

Livestock numbers growth

Base model output numbers growth 2000-2050 Livestock: 0.74%/yr Milk: 0.29%/yr

Increase in numbers growth of animals slaughtered by 30% Increase in animal yield by 30%

Reduction in numbers growth of animals slaughtered by 30% Reduction in animal yield by 30%

Food crop yield growth

Base model output yield growth rates 2000-2050: Cereals: %/yr: 1.02 R&T: %/yr: 0.35 Soybean: %/yr 0.36 Vegetables: %/yr 0.80 Sup-tropical/tropical fruits: 0.82%/yr

Increase yield growth by 60% for cereals, R&T, soybean, vegetables, ST fruits & sugarcane, dryland crops, cotton Increase production growth of oils, meals by 60%

Reduce yield growth by 60% for cereals, R&T, soybean, vegetables, fruits & sugarcane, dryland crops, cotton Increase production growth of oils, meals by 60%

Irrigated area growth (apply to all crops)

0.06

Increase by 25%

Reduction by 25%

Rain-fed area growth (apply to all crops)

0.18

Decrease by 15%

Increase by 15%

Basin efficiency

 

Increase by 0.15 by 2050, constant rate of improvement overtime

Reduce by 0.15 by 2050, constant rate of decline over time

Access to water

 

Increase annual rate of improvement by 50% relative to baseline level, (subject to 100 % maximum)

Decrease annual rate of improvement by 50% relative to baseline level, constant rate of change over time

Female secondary education

 

Increase overall improvement by 50% relative to 2050 baseline level, constant rate of change over time unless baseline implies greater (subject to 100 % maximum)

Decrease overall improvement by 50% relative to 2050 baseline level, constant rate of change over time unless baseline implies less

Source: Authors.