Projects
Projects: Projects for Investigator |
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| Reference Number | NF0427 | |
| Title | Crop physiological responses to plant density and harvest frequency in short rotation coppice | |
| Status | Completed | |
| Energy Categories | Renewable Energy Sources(Bio-Energy, Applications for heat and electricity) 100%; | |
| Research Types | Basic and strategic applied research 100% | |
| Science and Technology Fields | BIOLOGICAL AND AGRICULTURAL SCIENCES (Biological Sciences) 100% | |
| UKERC Cross Cutting Characterisation | Not Cross-cutting 100% | |
| Principal Investigator |
Project Contact No email address given ADAS UK Ltd |
|
| Award Type | Standard | |
| Funding Source | DEFRA | |
| Start Date | 01 December 2002 | |
| End Date | 31 March 2003 | |
| Duration | 4 months | |
| Total Grant Value | £48,581 | |
| Industrial Sectors | No relevance to Underpinning Sectors | |
| Region | London | |
| Programme | DEFRA Bioenergy | |
| Investigators | Principal Investigator | Project Contact , ADAS UK Ltd (100.000%) |
| Web Site | ||
| Objectives | 1. To identify the effect of spacing, variety and harvest frequency on SRC yield after two (triennial) or three (biennial) harvests. 2. To continue to test the initial hypotheses relating to resource capture and yield, that high yields are supported by high plant densities and high cutting frequencies. 3. To continue to attempt to relate pre-harvest stem dimensions with harvested yields. 4. To make stem measurement data available to Forest Research (Mensuration Branch) in order to assist the m with their yield modelling work. 5. To identify the impact of harvest frequency on yield accumulation. 6. To report the findings of all three phases of this work in one consolidated report. | |
| Abstract | The UK is committed to meeting 10% of its electricity requirements from renewable energy sources by 2010. This is in order to meet UK and EC commitments to the Kyoto Protocol, which the EC has recently ratified. This Protocol aims to reduce greenhouse gas emissions by 12.5% relative to 1990 levels. More recent proposals suggest that the commitment to Renewable Energy should by that it provides 20% of our energy needs by 2020. Generating electricity from biomass crops - crops specifically grown for harvest and thermochemical conversion to electricity - has been identified as one of the predominant routes for renewable energy generation in the UK, and as much as 125,000 hectares of biomass crops are anticipated in England alone. Short rotation coppice willow (Salix) is the biomass crop closest to full market development in the UK and is supported by planting grants in England. The key requirement of energy crops is that they intercept and convert efficiently to biomass as much radiation incident on the crop canopy as possible. Motivated by concerns within the coppice industry that commercial yields were much lower than anticipated ADAS began a DEFRA-funded experiment in 1996 which aimed to examine the relationship between plant density, species and harvest frequency on SRC resource capture and yield. The experiment studied the crop’s performance at two sites, for one harvest cycle only. The results of the initial project can be summarised as follows: In the first harvest cycle, higher yields were attainable from higher planting densities. Biennial harvesting increased yield compared with triennial harvests. Yield-density relationships were well described by logarithmic regression curves of the general form (y=a+b.rx). Although self-thinning responses could be seen in both S. viminalis and S. x dasyclados, harvesting after two seasons was sufficient to mitigate against these competitive yield-reducing effects. Annualised yields of dry matter ranged between 7- 12 t ha-1 yr-1. These results indicated that significant modifications to the establishment guidelines of SRC might be needed, employing higher planting rates in order to maximise resource capture. In order to evaluate the robustness of those results as the coppice matured, the second harvest of biennial cutting treatments was evaluated in December 2000. There was no significant variation in yield due to plant density, nor were there any significant interaction effect in the data, suggesting that density-induced self thinning was now affecting yield at the higher plant densities. These data indicated that the yield improvements seen initially may have been transient due to intra-specific competition effects. The work proposed here, phase 3 of the study, has the main objective of establishing conclusively whether the yield advantages seen with high planting densities in the first harvest cycle do persist into the mature phase of coppice production. It is proposed that the entire experiment is harvested in December 2002, thus studying the third cycle of yield in biennially harvested plots and the second cycle of yield in triennially harvested plots. In addition, plant morphology measurements will be taken in order to refine the non-destructive yield assessment techniques developed in earlier phases of the work. All three phases of the work will be consolidated in one final report for the project, which will be presented to the DEFRAR&D review scheduled for March 2003. DEFRAs policy objectives – to increase SRC profitability and support the development of a sustainable energy crop market – are best supported by the development of new techniques, such as those tested in this work, that will increase yields without increasing inputs. | |
| Publications | (none) |
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| Final Report | (none) |
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| Added to Database | 22/12/11 | |
