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Scoping study on the potential impact of environmental factors associated with climate change on major UK crops - AC0309

The aim of this scoping study is to evaluate the potential impacts, of a range of environmental factors linked to climate change, on crops growing in the UK. The study will include the effect of predicted changes in CO2 levels, temperature and tropospheric ozone on yields, water use efficiency, leaf temperature, evapo-transpiration and physiological thresholds. The study will draw on published literature in scientific journals and reports from relevant public bodies, including Defra. It will indicate where more research is needed and where adaptation will be necessary.

The consensus of scientific opinion as represented by the IPCC assessments reported in UKCIP08 is that the global climate system is warming. This is in response to changes in the composition of the atmosphere which are very likely to include a significant contribution from human activities. The major atmospheric component forcing warming is CO2, the level of which has doubled since pre-industrial times and now is at about 380 ppm and continuing to rise.

As a consequence of climatic warming, average temperature has risen by about 1oC in Central England since the 1970s with the prospect of a similar increase by the 2020s. Predicted changes for the UK also include seasonal and regional changes in the pattern of rainfall. Summers are likely to be wetter in the South, winters wetter in the North but an overall reduction on an annual basis.

A further global trend is for increasing levels of nitrogen oxides as a result of human activities. As a consequence, the background levels of tropospheric ozone, which is formed as a consequence of photochemical reactions of nitrogen oxides with volatile organic compounds, is increasing year on year.

All of the above changes will have an impact on agricultural cropping systems, including effects on and the efficiency of land and resource usage. Some factors, such as increased CO2 and temperature may be expected to have positive impacts, while for others, including water availability and troposperic ozone, the impact is likely to be detrimental.

Against this background, the project will review the relevant literature to identify the likely physiological consequences of the changes in CO2, temperature, rainfall and stratospheric ozone levels that are predicted to occur as a consequence of climate change. It will identify effects that are likely to be significant for specific crops and those which can be regarded as generic effects. The study will include findings from experiments from controlled environment studies, from field scale studies and from crop modelling work. One aim will be to evaluate the extent to which findings from small scale experiments can be extrapolated to crop levels.

The study will cover major, economically important UK crops including cereals, oil seeds and bioenergy crops and present the findings in ways such as crop x effect matrices that will be accessible to non-specialists and policy formers. The report will identify knowledge gaps and make proposals for further research to facilitate crop adaptation to climate change.
Objective 1: To review the relevant scientific literature to identify the likely physiological consequences of the changes in temperature, CO2 and stratospheric ozone levels. (3 months: Milestone 1)

Crop performance is ultimately dependent on photosynthetic assimilation. Carbon dioxide is the primary substrate for photosynthesis and there is a wealth of literature on how photosynthesis responds to changes in carbon dioxide levels. Models of crop performance driven by photosynthetic productivity that take into account changes in temperature ozone, water and carbon dioxide are a prerequisite for predicting the potential impact of climate change and guide where adaptation will be necessary. In this context, the following questions will guide the literature to be included:

• What effect will increases in carbon dioxide levels from current levels of about 380 ppm to the target maximum by 2050 of 550 ppm have on photosynthesis?
• What other physiological processes may be affected?
• How do changes in photosynthesis interact with other environmental factors such as water usage?
• How does ozone interact with photosynthesis and what are the implications for water usage?
• How do whole plant studies extrapolate to crop responses?
• What studies have been carried out at crop level relevant to prospective UK changes?
• What factors need to be considered for different crop types (cereals, oilseeds, bioenergy crops)?

Objective 2:
To review reports of work funded by Defra, NERC and other public bodies and draw out relevant findings and conclusions (4 months, Milestone 2).

Several public bodies, including Defra, NERC, the EU and BBSRC have funded research relevant to this topic. The findings from these studies are available in project reports, which may include material not published in scientific journals. A systematic search will be undertaken to identify such reports and capture relevant findings. As one of the aims of this exercise is to propose requirements for future research. This evaluation will therefore also aim to identify relevant centres of expertise and facilities in UK Academic and Research establishments for such studies.

Objective 3:
To produce a summary of emerging findings for discussion with Defra project officers (4 months Milestone 3).

A short, interim report with headline findings will be produced within the first 4 months of the project. This will identify key knowledge gaps and suggest areas for future research. This will be presented to the relevant Defra project officers and a topic for further experimentation between months 7 and 12 will be agreed.

Objective 4:
A full final report of the scoping study will be produced by the end of the 6th month. This will include review of the science in a form suitable for publication, an assessment of the relevance to UK agriculture and the likely impact of climate change, a compendium of UK expertise and facilities for studying the impact of climate change on UK cropping and suggestions for future research priorities (6 months, Milestone 5).

Project Documents
• FRP - Final Report : AC0309 SID 5   (321k)
• ANX - Annex : AC0309 - Final Report ANNEX 1   (414k)
• ANX - Annex : AC0309 - Final Report ANNEX 2   (237k)
Time-Scale and Cost
From: 2008

To: 2009

Cost: £59,840
Contractor / Funded Organisations
Warwick - HRI
Agriculture and Climate Change              
Allocated - WHRI              
Sustainable Farming and Food Science              
Fields of Study
Agriculture and Climate Change