Effects of climate change on productivity of cereals and legumes; model evaluation of observed year-to-year variability of the CO2 response (original) (raw)
Related papers
European Journal of Agronomy, 1999
In the ESPACE-Wheat programme, 25 open-top chamber experiments were carried out in 1994, 1995 and 1996, on nine locations, divided over eight European countries. In most experiments, spring wheat cv. Minaret was subjected to two levels of atmospheric CO 2 and two levels of ozone. Grain yields in the control treatments (ambient levels of CO 2 and O 3) varied strongly between sites. Also, yield response to elevated CO 2 and O 3 showed great variation. The present study was conducted to determine whether climatic differences between sites could account for the observed variation. Two simulation models were used for the analysis: AFRCWHEAT2-O3 and LINTULCC. AFRCWHEAT2-O3 simulates phenology, canopy development and photosynthesis in greater detail than LINTULCC. Both models account for the effects of radiation and temperature on crop growth. New algorithms were developed to simulate the effects of CO 2 and O 3. Weather data that were measured in the experiments were used as input, and simulated growth responses to CO 2 and O 3 were compared with measurements. No attempt was made to merge the two models. Thus two independent tools for analysis of data related to climate change were developed and applied. The average measured grain yield in the control treatment, across all 25 experiments, was 5.9 tons per hectare (t ha−1), with a standard deviation (SD) of 1.9 t ha−1. The models predicted similar average yields (5.5 and 5.8 t ha−1 for AFRCWHEAT2-O3 and LINTULCC, respectively), but smaller variation (SD for both models: 1.2 t ha−1). Average measured yield increase due to CO 2-doubling was 30% (SD 22%). AFRCWHEAT2-O3 expected a slightly lower value (24%, SD 9%), whereas LINTULCC overestimated the response (42%, SD 11%). The average measured yield decrease due to nearly-doubled O 3 levels was 9% (SD 11%). Both models showed similar results, albeit at lower variation (7% yield decrease at SDs of 6 and 4%). Simulations accounted well for the observation that, at elevated CO 2 , the percentage yield loss due to O 3 was lower than at ambient CO 2. The models predicted lower variation among sites and years than was measured. Yield response to CO 2 and O 3 was predicted to depend on the climate, with a predominant effect of temperature on the response to CO 2. In the measurements, these climatic effects were indeed observed, but a greater part of the variation was not related to light intensity, temperature, CO 2 , or O 3. This unexplained variability in the measured dataset was probably caused by factors not accounted for in the models, possibly related to soil characteristics. We therefore conclude that even perfect information on the climate variables examined in ESPACE-Wheat, i.e. light intensity and temperature, by itself would be insufficient for accurate prediction of the response of spring wheat to future elevated levels of CO 2 and O 3 .
Agricultural and Food Science, 1996
The experimental plants: spring wheat, winterwheat, spring barley, meadow fescue, potato, strawberry and black currant were sown or planted directly in the field, part of which was covered by an automatically controlled greenhouse to elevate the temperature by 3°C. The temperature of the other part of the field (open field) was not elevated, but the field was covered with the same plastic film as the greenhouse to achieve radiation and rainfall conditions comparable to those in the greenhouse. To elevate the CO2 concentrations, four open top chambers (OTC) were built for the greenhouse, and four for the open field. Two of these, both in the greenhouse and in the open field, were supplied with pure CO2 to elevate their CO2 level to 700 ppm. The temperatures inside the greenhouse followed accurately the desired level. The relative humidity was somewhat higher in the greenhouse and in the OTC:s than in the open field, especially after the modifications in the ventilation of the greenho...
Yield response of important field crops to elevated air temperature and CO 2 level
Field experiment was carried out to study the yield responses of important field crops to elevated air temperature and CO 2 fertilization at the Indian Agriculture Research Institute, New Delhi. One promising variety each of rice (Oryza sativa L.), wheat (Triticum aestivum L.), chickpea (Cicer arietinum L.), greengram (Vigna radiata (L) Wilczek), groundnut (Arachis hypogaea L.), mustard (Brassica juncea (L.) Czern & Coss) and potato (Solanum tuberosum L.) were grown to full maturity in small temperature tunnels and FACE (Free Air CO 2 Enrichment) under increased temperature (1-4°C) and CO 2 level (550 ppm), respectively. Economic yield reduced gradually with rise in temperature in all the crops. Among the crops rice, chickpea and mustard have shown greater thermal tolerance, while wheat and groundnut proved to be more thermal sensitive. In case of greengram and potato, increased temperature effect was intermediate. On the other hand CO 2 fertilization enhanced the yield to varying degree in these field crops with highest effect in chickpea and least in cereals (rice and wheat). Results indicate that elevated CO 2 could alleviate the negative impact of temperature increase up to 4°C in chickpea and 5°C in mustard. In other crops, elevated CO 2 could counter-effect the temperature increase to lesser extent with least degree in wheat (1.5°C). Thus, counter effect of elevated CO 2 to rising temperature seems to be crop and location specific. Although, these results are preliminary in nature as experiments with more variables such as biotic factors like pests and weeds, geographical locations, agronomical practices are needed to find precise responses of crops to future climate change scenario.
Crop responses to climatic variation
Philosophical Transactions of the Royal Society B: Biological Sciences, 2005
The yield and quality of food crops is central to the well being of humans and is directly affected by climate and weather. Initial studies of climate change on crops focussed on effects of increased carbon dioxide (CO 2) level and/or global mean temperature and/or rainfall and nutrition on crop production. However, crops can respond nonlinearly to changes in their growing conditions, exhibit threshold responses and are subject to combinations of stress factors that affect their growth, development and yield. Thus, climate variability and changes in the frequency of extreme events are important for yield, its stability and quality. In this context, threshold temperatures for crop processes are found not to differ greatly for different crops and are important to define for the major food crops, to assist climate modellers predict the occurrence of crop critical temperatures and their temporal resolution. This paper demonstrates the impacts of climate variability for crop production in a number of crops. Increasing temperature and precipitation variability increases the risks to yield, as shown via computer simulation and experimental studies. The issue of food quality has not been given sufficient importance when assessing the impact of climate change for food and this is addressed. Using simulation models of wheat, the concentration of grain protein is shown to respond to changes in the mean and variability of temperature and precipitation events. The paper concludes with discussion of adaptation possibilities for crops in response to drought and argues that characters that enable better exploration of the soil and slower leaf canopy expansion could lead to crop higher transpiration efficiency.
Field Crops Research, 2004
The cropping systems simulation model APSIM-Nwheat was tested against detailed field measurements representing possible growing conditions under future climate change scenarios. Increasing average temperatures by 1.7 8C observed over several seasons at Obregon, Mexico reduced the time to flowering by 11 days and resulted in a decline of total biomass and grain yield. These effects were reproduced by the model, except when the observed total biomass inexplicably rose again in the fourth and fifth year, despite higher temperature and a much shorter growing time. In a water stress experiment, the effects of different timing and duration of water deficit on crop growth and yield were reproduced with the model for a rain-shelter experiment at Lincoln, New Zealand where observed grain yields were reduced from 10 to 4 t ha À1 due to increased water deficit. In experiments from Western Australia, reduced growth and yields due to extreme terminal water deficit were also reproduced with the model where measured yields fall below 0.5 t ha À1. In the Maricopa Free Air Carbon-Dioxide Enrichment (FACE) experiment in Arizona, USA, the largest yield increase occurred with elevated CO 2 in the dry and high N treatments, whereas little or no response was observed in the wet and low N supply treatments, as simulated with the model. Combining elevated CO 2 with increased temperature in a sensitivity analysis, two levels of water supply and a range of N applications indicated a positive effect of elevated CO 2 on yield as long as N was not limiting growth. Increased temperature and reduced water supply reduced yields and the yield response to N supply under ambient and elevated CO 2. Grain protein concentrations were reduced under elevated CO 2 , but the difference was minor with ample N fertiliser. Evapotranspiration was reduced under elevated CO 2. Higher temperatures increased evapotranspiration with low N input, but reduced it with ample N fertiliser, resulting in a reduction and an increase, respectively, in drainage below the root zone. In the Mediterranean environment of Western Australia the impact of elevated CO 2 and increased temperature on grain yield was in average positive, but varied with seasonal rainfall distribution. Based on the range of model testing experiments and the sensitivity analysis, APSIM-Nwheat was found suitable for studies on directional impacts of future climate change on wheat production. Due to some large discrepancies Field Crops Research 85 (2004) 85-102
Simulating the Effect of Climate Change on Yield of Crops
2005
Effect of changes in seasonal temperature, rainfall and radiation on yield of various crops was studied on the pooled dataset of various agro-ecological regions. Food production at national scale (annual as well as kharif) had correspondence with the annual!south-west monsoon rains, whereas the food production during rabi season did not show significant relationship with the winter rains as most of the cereals grown during the rabi-season are usually under assured irrigated condition. The dependence of yield of wheat, barley, gratn, rapeseed and mustard and maize with seasonal tempel'ature was evaluated for north-western region of the country. Water-nitrogen interaction effect was characterized through simulation runs for New Delhi environment, and the N-doze to be applied depended on the extent of water availability through irrigation! rainfall. The amount of winter rains received had significant effect on grain yield of wheat grown under limited moisture supply situation. The reduction factor for wheat, when grown under adequate inputs at research farm fields or the simulated outputs, was relatively higher than the value obtained at district level, which could be due to crops grown under the large extent of variations in biotic/abiotic stresses at regional scale. Optimal sowing date of wheat for various growing regions (at met-subdivision scale) was evaluated, and the extent of reduction in the attainable yield with pre-/post-sowing dates from the optimal date was evaluated using WTGROWS. The optimal dates were spatially variant, which mainly depended on the temperature during growing period of wheat. The adaptation strategy through delay in the date of sowing under various temperature rise scenarios was demonstrated for variolls growing locations. Wheat cultivars had differential response, in terms of growth and yield, with the temperature rise. The effect of aerosol or suspended particulate matter, through reduction in the amounts of solar radiation reaching the earth's surface, was evaluated through growth and yield response of wheat by running WTGROWS for New Delhi environtnent. and it could be concluded that the reduction in wheat yield was relatively lower for radiation reduction to the extent of } 5 per cent from the normal.
Climatic Change, 1996
The experiment described here resulted from simulation analyses of climate-change studies that highlighted the relative importance of changes in the mean and variance of climatic conditions in the prediction of crop development and yield. Growth and physiological responses of four old cultivars of winter wheat, to three temperature and two carbon dioxide (CO2) regimes (350 or 700 ppmv) were studied in controlled environment chambers. Experimental results supported the previous simulation analyses. For plants experiencing a 3 ~ increase in day and night temperatures, relative to local long-term mean temperatures (control treatment), anthesis and the end of grain filling were advanced, and grain and dry matter yields were reduced by 27% and 18%, respectively. Increasing the diurnal temperature range, but maintaining the same mean temperature as the control, reduced the maximum leaf area (27%) and grain yield (13%) but did not affect plant development. Differences among the temperature treatments in both phyllochron interval and anthesis date may have resulted from differences between measured air, and unmeasured plant, temperatures, caused by evaporative cooling of the plants. Thermal time (base ---0 ~ calculated from air temperature, from anthesis to the end of grain filling was about 650 ~ d for all cultivars and treatments. Doubling ambient CO2 concentration to 700 ppmv reduced maximum leaf area (21%) but did not infl uence plant development or tiller numbers.
Journal of The Royal Society Interface, 2021
Climate change effects on UK winter wheat grain yield are complex: warmer temperature, negative; greater carbon dioxide (CO 2 ) concentration, positive; but other environmental variables and their timing also affect yield. In the absence of long-term experiments where temperature and CO 2 concentration were manipulated separately, we applied the crop simulation model Sirius with long-term daily meteorological data (1892–2016) for Rothamsted, Hertfordshire, UK (2007–2016 mean growing season temperature 1.03°C warmer than 1892–1991), and CO 2 concentration over this period, to investigate the separate effects of historic CO 2 and weather on simulated grain yield in three wheat cultivars of the modern era. We show a slight decline in simulated yield over the period 1892–2016 from the effect of weather (daily temperature, rainfall and sunshine hours) at fixed CO 2 (294.50 ppm, 1892 reference value), but a maximum 9.4% increase when accounting for increasing atmospheric CO 2 (from 294.50...
Simulating the impact of climate change and its variability on growth and yield of crops
Climate Change and Environmental Sustainability, 2013
There is a need to delineate vulnerable regions and identify suitable adaptation and mitigation strategies to sustain agricultural productivity under global climate change and frequently occurring extreme climatic events. Agricultural productivity can be affected by climate change, directly, due to changes in temperature, precipitation or CO 2 levels, and indirectly, through changes in soil health (physical, chemical and biological), distribution and frequency of infestation by insects/pests. Field/control chamber-based multidisciplinary research results, covering soil-water-plant-insects-pests and atmospheric continuum processes, were used to develop dynamic/mechanistic crop growth models. These models, after thorough validation (namely WTGROWS, INFOCROP and DSSAT), have been successfully used for evaluating soil and crop processes in relation to climate change. Using these models, differential response of reduced crop yields to rising temperatures was noticed at locations. Interaction of delta change in CO 2 and temperature was significant, as noticed through growth and yield response of crops. Simulation using the WTGROWS model indicated that optimal sowing date in wheat advanced by 5-8 days per degree rise in temperature (adaptation strategy). The impact in crops was more pronounced in relatively warmer regions, which became highly adverse under limited supply of water and nutrients. Shifts in the productivity centres northward for major crops, in relation to temperature rise and enhanced CO 2 concentration, were noticed. Using WTGROWS and DSSAT, the impact of aerosol was evaluated on rice, wheat and sugarcane, and radiation reduction was compensated with the enhancement in duration of the crops due to cooling and marginal reduction in yield of crops was noticed. The crop-pest-weather interaction and socioeconomic components in the climate change impact evaluation are relatively weaker in the present models. In INFOCROP, insect-pest subroutine has been addressed and successfully used for climate change studies. There is a need to develop simulation models/life-cycle assessment methodology by integrating the multiwater/ nutrients interaction for realistic estimate of growth and yield of crops, in designing appropriate nutrient management strategies, in evaluating the environmental impacts and also in developing green crop nutrition products. Most of the climate change studies in the past are point based, extrapolated empirically for assessing the regional impacts of climate change. There is a need to evolve methodology for integrating relational layers of biophysical and socioeconomic inputs, along with climate change scenarios and crop simulation tools for region wise estimates of the impacts on agriculture, including vulnerability, mitigation and adaptation strategies.