Abstract
In the Central Rift Valley of Ethiopia (CRV), actual productivity of most cereals is less than 3 t ha−1 associated with low input use and poor crop management. After calibrating and validating the Agricultural Production System Simulator (APSIM) using experimental data, we explored and prioritized promising intensification options for rainfed maize and wheat that enable to narrow prevailing yield gaps in the CRV, and quantified trade-offs with the water balance and gross margins. We set up a factorial simulation experiment combining Genetic x Environment x Management factors that influence crop yield and water use at field scale to simulate yield and water balance components under current and future climate scenarios (pessimistic scenario for mid-century). Varietal selection and nitrogen (N) fertilization were the most important factors contributing to yield gap closure. Although yields were maximized with N application rates up to 250 kg−1 in most soils and varieties, maximum gross margin and maximum water use efficiency (WUE) were attained at lower N rates, associated with a small yield reduction compared to the maximum. There was a trade-off between intensification and increased absolute water use through transpiration, while the water use per kg product was decreased. However, location-specific N application rates that allow producing at least 80% of the water-limited potential yield (Yw) of maize and wheat resulted in high water use efficiencies as well as favorable cost-benefit ratios. Climate change was projected to lower yield as it advanced maturity, and to result in decreased drainage and increased soil evaporation across all variety, location and management combinations for both crops. Climate change reduced crop yield by 15–25% for wheat and 2–30% for maize. We conclude that the locally-calibrated APSIM model could be used to derive key lessons from the genetic, environment and management interactions, and generate information on sustainable intensification pathways that combine narrowing yield gaps with maximizing WUE and gross margins.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 15
Claim · model-written summary
Actual productivity of most cereals in the Central Rift Valley of Ethiopia is less than 3 t ha−1.
Verbatim
e0“In the Central Rift Valley of Ethiopia (CRV), actual productivity of most cereals is less than 3 t ha−1 associated with low input use and poor crop management”
Claim · model-written summary
Varietal selection and nitrogen fertilization were the most important factors for closing yield gaps.
- Taxon
- maize and wheat
Triticum aestivum
Zea mayse0 - Treatment
- Varietal selection and nitrogen (N) fertilizatione1
- Outcome
- yield gap closuree1
- Direction
- increaseinferrede1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“Varietal selection and nitrogen (N) fertilization were the most important factors contributing to yield gap closure”
Claim · model-written summary
Nitrogen application rates up to 250 kg−1 maximized simulated yields.
- Taxon
- maize and wheatTriticum aestivumZea mayse0
- Treatment
- N application rates up to 250 kg−1e1
- Outcome
- yieldse1
- Direction
- maximizede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“yields were maximized with N application rates up to 250 kg−1”
Claim · model-written summary
Lower N rates gave the maximum simulated gross margin, with a small yield reduction compared to the maximum.
- Taxon
- maize and wheatTriticum aestivumZea mayse0
- Treatment
- lower N ratese1
- Outcome
- gross margine1
- Direction
- maximume1
- Qualifier
- associated with a small yield reduction compared to the maximume1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“maximum gross margin and maximum water use efficiency (WUE) were attained at lower N rates, associated with a small yield reduction compared to the maximum”
Claim · model-written summary
Lower N rates gave the maximum simulated water use efficiency.
- Taxon
- maize and wheatTriticum aestivumZea mayse0
- Treatment
- lower N ratese1
- Outcome
- water use efficiency (WUE)e1
- Direction
- maximume1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“maximum gross margin and maximum water use efficiency (WUE) were attained at lower N rates, associated with a small yield reduction compared to the maximum”
Claim · model-written summary
Intensification was associated with increased absolute water use through transpiration.
- Taxon
- maize and wheatTriticum aestivumZea mayse0
- Treatment
- intensificatione1
- Outcome
- absolute water use through transpiratione1
- Direction
- increasede1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“There was a trade-off between intensification and increased absolute water use through transpiration”
Claim · model-written summary
Intensification decreased the water use per kg of product.
- Taxon
- maize and wheatTriticum aestivumZea mayse0
- Treatment
- intensificatione1
- Outcome
- water use per kg producte2
- Direction
- decreasede2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“There was a trade-off between intensification and increased absolute water use through transpiration”
e2“while the water use per kg product was decreased”
Claim · model-written summary
Location-specific N rates giving at least 80% of water-limited potential yield resulted in high water use efficiencies.
- Taxon
- maize and wheatTriticum aestivumZea mayse1
- Treatment
- location-specific N application rates that allow producing at least 80% of the water-limited potential yield (Yw)e1
- Outcome
- water use efficienciese1
- Direction
- highe1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“location-specific N application rates that allow producing at least 80% of the water-limited potential yield (Yw) of maize and wheat resulted in high water use efficiencies as well as favorable cost-benefit ratios”
Claim · model-written summary
The same location-specific N rates gave favorable cost-benefit ratios.
- Taxon
- maize and wheatTriticum aestivumZea mayse1
- Treatment
- location-specific N application rates that allow producing at least 80% of the water-limited potential yield (Yw)e1
- Outcome
- cost-benefit ratiose1
- Direction
- favorablee1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“location-specific N application rates that allow producing at least 80% of the water-limited potential yield (Yw) of maize and wheat resulted in high water use efficiencies as well as favorable cost-benefit ratios”
Claim · model-written summary
Climate change was projected to lower crop yield as maturity advanced.
- Taxon
- maize and wheatTriticum aestivumZea mayse0
- Treatment
- Climate changee1
- Outcome
- yielde1
- Direction
- lowere1
- Qualifier
- as it advanced maturitye1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“Climate change was projected to lower yield as it advanced maturity”
Claim · model-written summary
Climate change was projected to decrease drainage.
- Taxon
- maize and wheatTriticum aestivumZea mayse0
- Treatment
- Climate changee1
- Outcome
- drainagee2
- Direction
- decreasede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“Climate change was projected to lower yield as it advanced maturity”
e2“to result in decreased drainage and increased soil evaporation across all variety, location and management combinations for both crops”
Claim · model-written summary
Climate change was projected to increase soil evaporation.
- Taxon
- maize and wheatTriticum aestivumZea mayse0
- Treatment
- Climate changee1
- Outcome
- soil evaporatione2
- Direction
- increasede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“Climate change was projected to lower yield as it advanced maturity”
e2“to result in decreased drainage and increased soil evaporation across all variety, location and management combinations for both crops”
Claim · model-written summary
Climate change reduced wheat crop yield by 15–25%.
- Taxon
- wheatTriticum aestivume0
- Treatment
- Climate changee0
- Outcome
- crop yielde0
- Direction
- reducede0
- Value
- 15–25%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Climate change reduced crop yield by 15–25% for wheat and 2–30% for maize”
Claim · model-written summary
Climate change reduced maize crop yield by 2–30%.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Climate change reduced crop yield by 15–25% for wheat and 2–30% for maize”
Claim · model-written summary
The locally-calibrated APSIM model could be used to derive lessons and sustainable intensification pathways for maize and wheat.
- Taxon
- maize and wheatTriticum aestivumZea mayse0
- Outcome
- the locally-calibrated APSIM modele1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“we explored and prioritized promising intensification options for rainfed maize and wheat”
e1“We conclude that the locally-calibrated APSIM model could be used to derive key lessons from the genetic, environment and management interactions”
The same questions in other papers
climate site · physiology: water · Zea mays (maize)Positive and negative results
3 papers in the same direction as this paper · 2 in the opposite direction
- negative
- negative
- positive
2 papers more in this group
See all 6 papers →climate site · physiology: water · Triticum aestivum (wheat)Positive and negative results
3 papers in the same direction as this paper · 4 in the opposite direction
- negative
- negative
- negative
4 papers more in this group
See all 8 papers →nitrogen · physiology: water · Zea mays (maize)Positive and negative results
51 papers in the same direction as this paper · 6 in the opposite direction · 3 reporting no difference from an alternative
- negative
- negative
- no effect
57 papers more in this group
See all 61 papers →nitrogen · physiology: water · Triticum aestivum (wheat)Positive and negative results
87 papers in the same direction as this paper · 9 in the opposite direction · 4 reporting no difference from an alternative
- no effect
- no effect
- no effect
97 papers more in this group
See all 101 papers →climate site · yield · Triticum aestivum (wheat)Positive and negative results
71 papers in the same direction as this paper · 79 in the opposite direction · 3 reporting no difference from an alternative
- negative
- negative
- negative
150 papers more in this group
See all 154 papers →climate site · yield · Zea mays (maize)Positive and negative results
101 papers in the same direction as this paper · 73 in the opposite direction · 5 reporting no difference from an alternative
- negative
- negative
- negative
176 papers more in this group
See all 180 papers →nitrogen · yield · Triticum aestivum (wheat)Positive and negative results
1,736 papers in the same direction as this paper · 285 in the opposite direction · 39 reporting no difference from an alternative
- negative
- negative
- negative
2,057 papers more in this group
See all 2,061 papers →nitrogen · yield · Zea mays (maize)Positive and negative results
1,905 papers in the same direction as this paper · 234 in the opposite direction · 45 reporting no difference from an alternative
- positive
- positive
- negative
2,181 papers more in this group
See all 2,185 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.