A Canopy Transpiration and Photosynthesis Model for Evaluating Simple Crop Productivity Models

Kremer, Cristián; Stöckle, Claudio O.; Kemanian, Armen R.; Howell, Terry A.

doi:10.2134/advagricsystmodel1.c6

Cited by 13 publications

(9 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Calculated values for TUE of rainfed maize exceeded maximal values of 83 kg ha −1 mm −1 asserted by Kremer et al. (). The high TUE in the present study may result from severe soil water deficits early in the growing seasons.…”

Section: Discussionmentioning

confidence: 43%

Drought Tolerance and Water‐Use Efficiency of Biogas Crops: A Comparison of Cup Plant, Maize and Lucerne‐Grass

Schoo

Wittich

Böttcher

et al. 2016

J Agronomy Crop Science

View full text Add to dashboard Cite

The cup plant (Silphium perfoliatum L.) is discussed as an alternative energy crop for biogas production in Germany due to its ecological benefits over continuously grown maize. Moreover, a certain drought tolerance is assumed because of its intensive root growth and the dew water collection by the leaf cups, formed by fused leaf pairs. Therefore, the aim of this study was to estimate evapotranspiration (ET), water-use efficiency (WUE) and the relevance of the leaf cups for the cup plant's water balance in a 2-year field experiment. Parallel investigations were conducted for the two reference crops maize (high WUE) and lucerne-grass (deep and intensive rooting) under rainfed and irrigated conditions. Root system performance was assessed by measuring water depletion at various soil depths. Transpiration-use efficiency (TUE) was estimated using a model approach. Averaged over the 2 years, drought-related above-ground dry matter reduction was higher for the cup plant (33 %) than for the maize (18 %) and lucerne-grass (14 %). The WUE of the cup plant (33 kg ha À1 mm À1 ) was significantly lower than for maize (50 kg ha À1 mm À1 ). The cup plant had a lower water uptake capacity than lucerne-grass. Cup plant dry matter yields as high as those of maize will only be attainable at sites that are well supplied with water, be it through a large soil water reserve, groundwater connection, high rainfall or supplemental irrigation.

show abstract

Section: Discussionmentioning

confidence: 43%

Drought Tolerance and Water‐Use Efficiency of Biogas Crops: A Comparison of Cup Plant, Maize and Lucerne‐Grass

Schoo

Wittich

Böttcher

et al. 2016

J Agronomy Crop Science

View full text Add to dashboard Cite

show abstract

“…Components of the water balance include crop interception, soil evaporation, transpiration, run-off and drainage that provide daily soil water content. (Monteith 1981), and variable coefficients of TE (Kremer et al, 2008). The minimum of the two calculations each day of the growing season determines the dry matter production for the day.…”

Section: Simulation Modelsmentioning

confidence: 99%

Response of wheat growth, grain yield and water use to elevated CO₂ under a Free‐Air CO₂ Enrichment (FACE) experiment and modelling in a semi‐arid environment

O’Leary¹,

Christy²,

Nuttall³

et al. 2015

Global Change Biology

164

View full text Add to dashboard Cite

The response of wheat crops to elevated CO 2 (eCO 2) was measured and modelled with the Australian Grains Free‐Air CO 2 Enrichment experiment, located at Horsham, Australia. Treatments included CO 2 by water, N and temperature. The location represents a semi‐arid environment with a seasonal VPD of around 0.5 kPa. Over 3 years, the observed mean biomass at anthesis and grain yield ranged from 4200 to 10 200 kg ha−1 and 1600 to 3900 kg ha−1, respectively, over various sowing times and irrigation regimes. The mean observed response to daytime eCO 2 (from 365 to 550 μmol mol−1 CO 2) was relatively consistent for biomass at stem elongation and at anthesis and LAI at anthesis and grain yield with 21%, 23%, 21% and 26%, respectively. Seasonal water use was decreased from 320 to 301 mm (P = 0.10) by eCO 2, increasing water use efficiency for biomass and yield, 36% and 31%, respectively. The performance of six models (APSIM‐Wheat, APSIM‐Nwheat, CAT‐Wheat, CROPSYST, OLEARY‐CONNOR and SALUS) in simulating crop responses to eCO 2 was similar and within or close to the experimental error for accumulated biomass, yield and water use response, despite some variations in early growth and LAI. The primary mechanism of biomass accumulation via radiation use efficiency (RUE) or transpiration efficiency (TE) was not critical to define the overall response to eCO 2. However, under irrigation, the effect of late sowing on response to eCO 2 to biomass accumulation at DC65 was substantial in the observed data (~40%), but the simulated response was smaller, ranging from 17% to 28%. Simulated response from all six models under no water or nitrogen stress showed similar response to eCO 2 under irrigation, but the differences compared to the dryland treatment were small. Further experimental work on the interactive effects of eCO 2, water and temperature is required to resolve these model discrepancies.

show abstract

“…However, the stomatal optimization hypothesis of Cowan and Farquhar (1977) states the marginal water use efficiency leans toward a constant; based on this assumption, it can be shown that w is proportional to the square root of D (w = k/D β with β = 0.5) and that the ratio of internal (leaf) to external (air) CO 2 concentration decreases as stomata close. Kemanian et al (2005) showed that this relation seems to hold true for many species and estimated that β = 0.59 for barley and wheat; Kremer et al (2008) estimated that β = 0.44 for maize. Although the apparent alignment of theory and data is pleasing, there is substantial dispersion in any k estimation and variation among genotypes is hard to quantify and requires a refined understanding of the environmental interactions (Condon et al, 1993).…”

Section: Biomass Productionmentioning

confidence: 99%

“…Carbon is partitioned into aerial (stems, leaves, and grains) and root portions, and expressed as biomass based on its carbon requirement and chemical composition, which are associated with growth and maintenance respiration (Penning de Vries et al, 1983). An advantage of these models is that photosynthesis and transpiration are linked via stomatal conductance, the latter responding to environmental conditions such as light, CO 2 concentration, and humidity (e.g., Kremer et al, 2008). These models provide excellent explanatory frameworks, but their usefulness may be challenged by the large number of parameters, the correlation among parameters, uncertainties associated with their values, the need to integrate photosynthesis and transpiration throughout the crop canopy, and the growth-photosynthesis feedback.…”

Section: Biomass Productionmentioning

confidence: 99%

Can Crop Models Identify Critical Gaps in Genetics, Environment, and Management Interactions?

Stöckle

Kemanian

2020

Front. Plant Sci.

Self Cite

View full text Add to dashboard Cite

Increasing food demand under climate change constraints may challenge and strain agricultural systems. The use of crop models to assess genotypes performance across diverse target environments and management practices, i.e., the genetic × environment × management interaction (GEMI), can help understand suitability of genotype and agronomic practices, and possibly accelerate turnaround in plant breeding programs. However, the readiness of models to support these tasks can be debated. In this article, we point out modeling and data limitations and argue the need for evaluation and improvement of relevant process algorithms as well as model convergence. Under conditions suitable for plant growth, without meteorological extremes or soil limitation to root exploration, models can simulate resource capture, growth, and yield with relative ease. As stresses accumulate, the plant species-and genotype-specific attributes and their interactions with the soil and atmospheric environment generate a large range of responses, including conditions where resources become so limiting as to make yields very low. The space in between high and low yields is where most rainfed production occurs, and where the current model and user skill at representing GEMI varies. We also review studies comparing the performance of a large number of crop models and the lessons learned. The overall message is that improvement of models appears as a necessary condition for progress, and perhaps relevancy. Model ensembles help mitigate data input, model, and user-driven uncertainty for some but not all applications, sometimes at a very high cost. Successful model-based assessment of GEMI not only requires better crop models and knowledgeable users, but also a realistic representation of the environmental conditions of the landscape where crops are grown, which is not trivial given the 3D nature of water and nutrient transport. Models remain the best quantitative repository of our knowledge on crop functioning; they contain a narrative of plant, soil, and atmospheric functioning in computer language and train the mind to couple processes. But in our quest to tame GEMI, will they lead the way or just ride along history?

show abstract

A Canopy Transpiration and Photosynthesis Model for Evaluating Simple Crop Productivity Models

Cited by 13 publications

References 44 publications

Drought Tolerance and Water‐Use Efficiency of Biogas Crops: A Comparison of Cup Plant, Maize and Lucerne‐Grass

Drought Tolerance and Water‐Use Efficiency of Biogas Crops: A Comparison of Cup Plant, Maize and Lucerne‐Grass

Response of wheat growth, grain yield and water use to elevated CO₂ under a Free‐Air CO₂ Enrichment (FACE) experiment and modelling in a semi‐arid environment

Can Crop Models Identify Critical Gaps in Genetics, Environment, and Management Interactions?

Contact Info

Product

Resources

About

A Canopy Transpiration and Photosynthesis Model for Evaluating Simple Crop Productivity Models

Cited by 13 publications

References 44 publications

Drought Tolerance and Water‐Use Efficiency of Biogas Crops: A Comparison of Cup Plant, Maize and Lucerne‐Grass

Drought Tolerance and Water‐Use Efficiency of Biogas Crops: A Comparison of Cup Plant, Maize and Lucerne‐Grass

Response of wheat growth, grain yield and water use to elevated CO2 under a Free‐Air CO2 Enrichment (FACE) experiment and modelling in a semi‐arid environment

Can Crop Models Identify Critical Gaps in Genetics, Environment, and Management Interactions?

Contact Info

Product

Resources

About

Response of wheat growth, grain yield and water use to elevated CO₂ under a Free‐Air CO₂ Enrichment (FACE) experiment and modelling in a semi‐arid environment