CERES :: Browsing by Author "Parsons, David J."

Browsing by Author "Parsons, David J."

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Open Access
Analysis of the 2007/8 Defra Farm Business Survey Energy Module
(2010-11-30T00:00:00Z) Williams, Adrian G.; Pearn, Kerry R.; Sandars, Daniel L.; Audsley, Eric; Parsons, David J.; Chatterton, Julia C.
Key points This study has delivered an invaluable baseline estimate of energy use and greenhouse gas (GHG) emissions on commercial farms in England. Energy use and GHG emissions associated with particular commodities were quantified and results broadly agreed with those derived by Life Cycle Assessment, but with much scatter in the environmental performance of farms.Direct energy use on farms was generally less that indirect (embedded) energy use, except for horticulture, which is dominated by heating fuel use. In contrast, most GHG emissions are incurred on farms, rather than as embedded emissions.Scatter in both environmental and economic performance underlies the somewhat disappointing finding of no clear positive link between farm financial performance and energy use or GHG emissions. However, the mere existence of these ranges shows that there is scope for improvement in both financial and environmental performance and that there is no apparent barrier for both to be achievable in harmony. The recording of such farm-level energy data is essential for the future, as it should enable improvements to be made in efficiency of energy use. The improved UK agricultural GHG inventory will depend on high quality energy data on agricultural activities. This study will be invaluable in identifying the level of detail needed. Future data requirements include: contractor work rates and fuel use per unit area and per unit time, fertiliser and pesticide use by brand name, enhanced output data, especially animal live weights, and horticultural produce recorded by weight rather than by value.
Open Access
Assessing preferences for cultural ecosystem services in the English countryside using Q methodology
(MDPI, 2023-01-26) Hubatova, Marie; McGinlay, James; Parsons, David J.; Morris, Joe; Graves, Anil R.
Cultural Ecosystem Services (CES) are difficult to assess due to the subjective and diverse way in which they are experienced. This can make it difficult to apply CES research to enhance human experience of nature. This study applies Q methodology to group people according to their preferences for CES. The Q methodology survey was carried out with 47 local residents and tourists in Wiltshire, in South West England. Four groups of respondents were identified drawing value from nature through: (1) spiritual benefits and mental well-being (Group 1—Inspired by nature); (2) nature and biodiversity conservation (Group 1—Conserving nature); (3) cultural heritage in multifunctional landscapes (Group 3—Countryside mix); and (4) opportunities for outdoor activities (Group 4—Outdoor pursuits). All four groups stated that benefits from nature were enhanced by actually visiting the countryside, through a better understanding of nature itself, and through a range of sensory experiences. They particularly identified relaxation opportunities as a very important CES benefit. These findings, and the demonstrated use of the Q methodology, could support local planning and landscape management in order to provide accessible and functional landscapes that can provide a range of different CES benefits to people.
Open Access
Assessing the effect of interventions on the risk of cattle and sheep carrying Escherichia coli O157:H7 to the abattoir using a stochastic model of the transmission of E. coli O157:H7 on the farm
(Elsevier Science B.V., Amsterdam., 2007-04-16T00:00:00Z) Stacey, K. F.; Parsons, David J.; Christiansen, K. H.; Burton, C. H.
Open Access
Carbon Brainprint Case Study: ceramic coatings for jet engine turbine blades
(2011-07-31T00:00:00Z) Parsons, David J.; Chatterton, Julia C.; Nicholls, John R.
Ceramic thermal barrier coatings (TBCs) are applied to jet turbine blades to protect them from the high temperature gases leaving the combustion chamber and to increase the efficiency of the engine. Professor John Nicholls of the Surface Science and Engineering Group, Cranfield University has been working with Rolls- Royce plc for about 17 years to improve the insulating performance of TBCs. As a result, the TBCs used in the current generation of aircraft turbofan jet engines achieve a temperature drop about 80ºC greater than at the start of the work, with an estimated fuel saving of about 1%. This case study considered two engine types: Trent 700, used on about half the Airbus A330 aircraft currently in service, and Trent 500, used on all Airbus A340-500 and A360-600 aircraft. The greenhouse gas emissions considered were, in order of magnitude, carbon dioxide from combustion of the fuel, emissions during extraction and refining of the fuel, and emissions of other greenhouse gases during combustion. Emissions associated with transport of the fuel were found to be negligible compared with these, and all emissions not related to fuel consumption, for example manufacture of the coating, were also assumed to be insignificant or excluded from the assessment because they were unaffected by the change in the TBC. The baseline fuel consumption during each flight phase (landing and take-off cycle and cruise) was estimated from publicly available data. Airline activity data for A330 and A340 models from European operators was taken to represent typical patterns of use, enabling annual emissions per aircraft to be calculated. Data on current operating aircraft and orders were then used to estimate the total current and projected future emissions. From these, the higher emissions that would have occurred in the past if the improved TBCs had not been used, and the corresponding future emissions, were estimated. The best estimates of the current emissions (the retrospective brainprint) for individual aircraft were 1016, 1574 and 1646t CO2e/year for A330, A340-500 and A340-600 respectively, giving 568 kt CO2e/year for the total fleet. Including all the aircraft on order, the prospective emissions reduction was 833kt CO2e/ year. Assuming a service life of 20 years, the total brainprint was approximately 17MtCO2e. An uncertainty analysis was performed with assumed uncertainties for aircraft activity, fuel consumption and the efficiency change. The 95% confidence interval for the current annual emissions reduction was 429-721kt CO2e/year excluding the efficiency change uncertainty, and 258-1105 if it was included. The relative changes in the other output measures were similar. Assuming that older engines do not and will not benefit from the improvement, reduced the total brainprint to 14MtCO2e. The assessment did not include an adjustment for the effect of emissions at high altitude, which would increase all the outputs by a factor of 1.9.
Open Access
Carbon Brainprint Case Study: improved delivery vehicle logistics
(2011-07-31T00:00:00Z) Parsons, David J.; Chatterton, Julia C.; Bernon, Mike; Palmer, Andrew
Road transport accounts for about 20% of the total GHG emissions of the UK, and HGVs andLGVs are responsible for about one-third of these. The total direct GHG emissions from HGVsand LGVs in 2008 were about 40 Mt CO2e. Dr Andrew Palmer, a Cranfield University visiting fellow and former PhD student contributed tothe transport recommendations for the food distribution industry following publication of TheFood Industry Sustainability Strategy. These recommendations were taken up by IGD as part ofthe Efficient Consumer Response (ECR - UK) initiative and implemented with 40 leading UKbrands. They reported that this initiative had taken off 124 million road miles (equivalent to 60million litres of diesel fuel) from UK roads over three years (2007-2009) and 163 million roadmiles up to 2010, with a target of 200 million road miles by the end of 2011. The quoted reduction in vehicle use up to 2010 is equivalent to 250 kt CO2e, but this cannot allbe attributed to Cranfield University's carbon brainprint, because Dr Palmer was only one of theauthors of the report and he was not an employee of the university at the time. We estimate theattributable brainprint to be 56 kt CO2e with a 95% confidence range of 32-87. Assuming that this is maintained until 2020, and assuming a 1%/year increase in efficiency independent of thiswork, which will reduce the future brainprint, gives an estimate of 187 kt CO2e (102-295) for theperiod 2007-2020.
Open Access
Carbon Brainprint Case Study: intelligent buildings
(2011-07-31T00:00:00Z) Parsons, David J.; Chatterton, Julia C.; Clements-Croome, Derek; Elmualim, Abbas; Darby, Howard; Yearly, Tom; Davies, Gareth J.
It is estimated that non-domestic buildings were responsible for 18% of UK total greenhousegas emissions (582 Mt CO2e/year) in 2010. Of non-domestic building emissions, 34%(36 Mt CO2e/year) was due to lighting, office equipment and catering and 46%(49 Mt CO2e/year) was due to heating. A team consisting of researchers at the University of Reading, the University's FacilitiesManagement Directorate and Newera Controls Ltd. conducted two separate investigations tomeasure and demonstrate the potential for two important and complementary approaches inachieving energy efficiency and greenhouse gas emission reductions in buildings. The firstfocused on influencing user behaviour, in an office building on the main campus. The secondconsidered an interventionist approach in an accommodation block at the Henley BusinessSchool using intelligent monitoring and control systems. To date, the first investigation has demonstrated a 20% saving in lighting, office equipment andcatering energy use, largely through user awareness and behaviour change. The second has indicated that savings in heating energy of the order of 24% can be achievedby enhancement of legacy Building Management Systems (BMS) using a Building EnergyManagement System (BEMS). There is also scope for further savings if the BEMS system isextended to other services such as lighting.
Open Access
Carbon Brainprint Case Study: novel offshore vertical axis wind turbines
(2011-07-31T00:00:00Z) Parsons, David J.; Chatterton, Julia C.; Brennan, Feargal P.; Kolios, Athanasios J.
As part of the transition to a ‘low carbon economy', renewable technologies are expected toplay an increasing role in reducing dependence on fossil fuels for energy and electricity. Windpower in particular is likely to become a much larger contributor to the UK's energy mix. Thecurrent dominant design for large, grid-connected wind turbines is a three blade rotor with ahorizontal rotating axis. The concept of a vertical axis wind turbine (VAWT) is relatively new, buthas several advantages over horizontal axis alternatives. It is able to capture the wind from anydirection, and the vertical axis is such that the rotor equipment is located at base level, makingit is simpler and less costly to install and maintain. The Energy Technologies Institute (ETI) is a UK-based company formed from global industriesand the UK government. One of three projects looking at new turbine design and concepts foroffshore wind is the Novel Offshore Vertical Axis (NOVA) project, a UK-based consortiumlaunched in January 2009 to look at the feasibility of a NOVA turbine. achieved through the installation of NOVA wind turbines, in comparison to conventionalhorizontal axis wind turbines (HAWTs) for offshore power generation. The increased powerrating of the NOVA turbines compared to current HAWTs is expected to provide considerablereductions in lifetime greenhouse gas emissions. It compared the emissions from 1 GWinstallations over 20 years, based on a life cycle analysis of construction, operation anddisposal. The comparison used the popular Vestas V90 3 MW model and the proposed NOVA10 MW units. The estimated lifetime emissions were 521 kt CO2e for the conventional design and419 kt CO2e for NOVA. Using budget share to attribute the reductions to the project partners,Cranfield's brainprint was 34 kt CO2e. As there are no current NOVA units in operation, there were high uncertainties associated withthe estimates. A Monte-Carlo simulation resulted in a mean difference in emissions betweenthe two installations of 102 kt CO2e, with a standard deviation of 108.
Open Access
Carbon Brainprint Case Study: optimising defouling schedules for oil- refinerypreheat trains
(2011-07-31T00:00:00Z) Parsons, David J.; Chatterton, Julia C.; Wilson, Ian; Ishiyama, Edward
In an oil refinery, crude oil is heated to 360-370°C before entering a distillation columnoperating at atmospheric pressure where the gas fraction and several liquid fractions withdifferent boiling points (e.g. gasoline, kerosene, diesel, gas oil, heavy gas oil) are separated off.The crude oil is heated in two stages. The preheat train - a series of heat exchangers - heats itfrom ambient temperature to about 270°C when it enters the furnace, known as the coil inlettemperature. The furnace then heats the oil to the temperature required for distillation.The purpose of the preheat train is to recover heat from the liquid products extracted in thedistillation column. Without this, 2-3% of the crude oil throughput would be used for heating thefurnace; with the preheat train up to 70% of the required heat is recovered. It also serves tocool the refined products: further cooling normally uses air or water. Over time, fouling reduces the performance of the heat exchangers, increasing the amount ofenergy that has to be supplied. It is possible to bypass units to allow them to be cleaned, withan associated cost and temporary loss of performance. The cleaning schedule thus has animpact on the overall efficiency, cost of operation and emissions. The group at the Department of Chemical Engineering and Biotechnology at Cambridgedeveloped a scheduling algorithm for this non-linear optimisation problem. It yields a good,though not-necessarily optimal, schedule and can handle additional constraints, such as thepresence of desalters with specific temperature requirements within the preheat train. This isnow being developed into a commercial software product. Data from two refineries - one operated by Repsol YPF in Argentina and the Esso FawleyRefinery in the UK - were used to model the systems and test the algorithm. For the Repsol YPF refinery, when compared with current practice and including a constrainton the desalter inlet temperature, the most conservative estimate of the emissions reductionwas 773 t CO2/year. This assumed a furnace efficiency of 90%. The emissions reductionincreased to 927 t CO2/year at 75% efficiency and 1730 t CO2/year at 40%. These were basedon a stoichiometric estimate of the emissions from the furnace. Using a standard emissionfactor increased them by 7.4%. For Esso Fawley, the estimated emission reduction compared to no maintenance was1435 t CO2/year at 90% furnace efficiency. This increased to 1725 t CO2/year at 75% and3225 t CO2/year at 40% efficienc
Open Access
Carbon Brainprint Case Study: training for landfill gas inspectors
(2011-07-31T00:00:00Z) Parsons, David J.; Chatterton, Julia C.; Longhurst, Philip J.
Anaerobic deterioration of biodegradable wastes in landfill sites is an important source ofgreenhouse gases. Of the estimated UK total of 2330 kt methane emitted in 2008, 966 kt(equivalent to 24 Mt of carbon dioxide) came from landfill, compared with 876 kt from livestockagriculture, the next largest source. Increasing the amount of methane that is recovered andused as fuel is an important method of reducing emissions. In 2008 Cranfield University was asked by the Environment Agency (EA) to run a 12 day course to train 12 EA officers, based on the knowledge of a retired EA industry expert. At the end of thecourse, the students split into two groups, each of which undertook 12 site visits. These 24sites were subsequently assessed by the EA, who estimated that the additional measuresrecommended had collected an additional 7,600 m3/hr of landfill gas. A further 12 officers havenow received the advanced training, and another 70 have attended a foundation course inwhich they learn how to audit and assess landfill gas controls on sites. The additional collection of methane resulting from the first set of visits is equivalent to453 kt CO2e/year. Extrapolating from this by making conservative assumptions about possiblediminishing returns, the savings to the end of 2010 from the two groups (the retrospectivebrainprint) are about 1,330 kt CO2e with a 95% confidence range of 1,091-1,570 kt CO2e. Usingthe same assumptions, if both groups continue working for a further three years, the savingsover the five year period (the prospective brainprint) will be 5,380 kt CO2e with a 95%confidence range of 3,695-7,309 kt CO2e.
Open Access
Carbon brainprint – An estimate of the intellectual contribution of research institutions to reducing greenhouse gas emissions
(Elsevier, 2015-05-07) Chatteron, Julia C.; Parsons, David J.; Nicholls, John R.; Longhurst, Philip J.; Bernon, Mike; Palmer, Andrew; Brennan, Feargal P.; Kolios, Athanasios; Wilson, Ian; Ishiyama, Edward; Clements-Croome, Derek; Elmualim, Abbas; Darby, Howard; Yearly, Tom; Davies, Gareth J.
Research and innovation have considerable, currently unquantified potential to reduce greenhouse gas emissions by, for example, increasing energy efficiency. Furthermore, the process of knowledge transfer in itself can have a significant impact on reducing emissions, by promoting awareness and behavioural change. The concept of the ‘carbon brainprint’ was proposed to convey the intellectual contribution of higher education institutions to the reduction of greenhouse gas emissions by other parties through research and teaching/training activities. This paper describes an investigation of the feasibility of quantifying the carbon brainprint, through six case studies. The potential brainprint of higher education institutes is shown to be significant: up to 500 kt CO2e/year for one project. The most difficult aspect is attributing the brainprint among multiple participants in joint projects.
Open Access
Carbon Brainprint: final report on HEFCE project LSDHE43
(2011-07-31T00:00:00Z) Parsons, David J.; Chatterton, Julia C.; Clements-Croome, Derek; Elmualim, A.; Darby, Howard; Yearly, T.; Wilson, I.; Ishiyama, Edward
The need for organisations to reduce their carbon footprint is now well accepted. HEFCE has recently published its policy (2010/01) requiring universities to set targets to reduce their greenhouse gas emissions and targeting reductions of 34% and 80% across the sector by 2020 and 2050 respectively. Universities, however, also help other organisations to reduce their own carbon footprints, both through providing existing or potential employees with the necessary knowledge and skills and, more directly, though research and consultancy projects. These reductions cannot be offset against the university's footprint, but the intellectual contribution to reducing the carbon footprint of others, termed their "carbon brainprint", is immensely valuable in meeting the challenge of global warming. This project aimed to help quantify the HE sector's Carbon Brainprint. It used a set of case studies from Cranfield, Cambridge and Reading Universities to establish a robust, repeatable method, informed by life cycle analysis methods and PAS2050 for carbon footprinting, for calculating and verifying the contribution of universities to reducing greenhouse gas emissions. This method could be applied across the sector to assess the impact of HE intellectual activities. Guidelines were drawn up at the start of the project and revised as the case studies progressed. These included general principles, based on carbon footprinting standards, appropriate spatial, temporal and conceptual boundaries for brainprint studies, the scope and limits of applicability, appropriate levels of detail, uncertainty analysis and the possible need to attribute the brainprint among project partners. The guidelines set out the main steps in a brainprint assessment: system description, boundary definition, data gathering, assessment of emissions and changes to evaluate the retrospective and prospective brainprint, and uncertainty analysis. The case studies covered * Ceramic thermal barrier coatings for jet engine turbine blades, which help to improve engine efficiency and reduce aircraft fuel consumption. * Novel offshore vertical axis wind turbines that will be able to generate ‘green' electricity using less material for construction than conventional designs. * Improved delivery vehicle logistics to reduce delivery vehicle fuel use in the food sector. * Training for landfill gas inspectors to capture emissions of methane from landfill sites. * Intelligent buildings to reduce fuel consumption by both behavioural change and advanced monitoring and control. * Optimising defouling schedules for oil-refinery preheat trains, to maintain efficiency and reduce the consumption of oil within the refinery. These included developments that were already implemented in practice, including some where data on the results were available, and others that have yet to be used. All demonstrated the positive effects of research, consultancy or teaching in reducing greenhouse gas emissions, although the scale of the effect varied considerably. The largest totals came from the jet engine thermal barrier coatings, due to the large quantities of fuel consumed by aircraft engines, and the training of landfill gas inspectors, due to substantial changes in the emissions of a highly potent greenhouse gas. In other cases the unit reductions were smaller, but the potential total effects are large if they are widely adopted. On the basis of these studies, it seems likely that a relatively small number of projects focussed on applications with high energy or greenhouse gas flows will represent the majority of the brainprint of most institutions. Those where good monitoring data from full-scale application are available will normally be comparatively simple to assess and provide clear results. The project has demonstrated that it is possible to begin to quantify the impact that universities have on society's greenhouse gas emissions, and that this impact is large. The current annual brainprint of the four projects assessed at Cranfield University is over 50 times the university's own annual carbon footprint.
Open Access
Comparison of automatic and guided learning for Bayesian networks to analyse pipe failures in the water distribution system
(Elsevier, 2019-02-06) Tang, Kayu; Parsons, David J.; Jude, Simon
The reliability of the water distribution system is critical to maintaining a secure supply for the population, industry and agriculture, so there is a need for proactive maintenance to help reduce water loss and down times. Bayesian networks are one approach to modelling the complexity of water mains, to assist water utility companies in planning maintenance. This paper compares and analyses how accurately the Bayesian network structure can be derived given a large and highly variable dataset. Method one involved using automated learning algorithms to build the Bayesian network, while method two involved a guided method using a combination of historic failure data, prior knowledge and pre-modelling data exploration of the water mains. By understanding common failure types (circumferential, longitudinal, pinhole and joint), the guided learning Bayesian Network was able to capture the interactions of the surrounding soil environment with the physical properties of pipes. The Bayesian network built using data exploration and literature was able to achieve an overall accuracy of 81.2% when predicting the specific type of water mains failure compared to the 84.4% for the automated method. The slightly greater accuracy from the automated method was traded for a sparser Bayes net where the interpretation of the interactions between the variables was clearer and more meaningful.
Open Access
A comparison of three modelling approaches for quantitative risk assessment using the case study of Salmonella spp. in poultry meat.
(Elsevier Science B.V., Amsterdam., 2005-01-15T00:00:00Z) Parsons, David J.; Orton, T. G.; D'Souza J.; Moore, A.; Jones, R.; Dodd, C. E. R.
A comprehensive review of both the scientific literature and industry practices was undertaken to identify and quantify all sources of contamination throughout the entire poultry meat production chain by Salmonella spp. This information was used to develop a quantitative risk assessment (QRA) model for Salmonella in the production chain from the breeder farm to the chilled carcass. This was subsequently used as the basis on which to compare the merits of three approaches to QRA modelling in such systems. The original model used a Bayesian Network (BN). The second method was a Markov chain Monte Carlo (MCMC) approach, a numerical Bayesian technique which retained a similar network structure but allowed further development, such as the separation of variability and uncertainty. The third method was a more detailed simulation model. The BN responds immediately to changes, such as entering evidence, because it does not use simulation and can propagate information from any point in the network to all others by Bayesian inference. However, it requires all the variables to be discrete, which introduces errors if continuous variables have to be discretized. These errors can accumulate. The MCMC approach does not require discrete variables while retaining some of the properties of the BN model, such as the ability to draw inferences from evidence. Finally, the simulation offers greater flexibility, such as consideration of the individual carcass, but may be more complex to implement as a result and sacrifices the ability to propagate evidence.
Open Access
Diffuse pesticide pollution of drinking water sources: impact of legislation and UK responses
(IWA Publishing, 2012-06-12T00:00:00Z) Dolan, Tom; Howsam, Peter; Parsons, David J.
Diffuse pesticide pollution is a problem for the environment, but it also presents a challenge for water compa- nies managing treatment infrastructure to produce potable water. The legal framework for this context has three main components: that dealing with pesticides and pesticide use, that dealing with environmental water quality and that dealing with drinking water quality. The study set out to identify, interpret and assess the impact of the legal framework related to this challenge. The study found that the current policy and legislation do not provide a coordinated legal framework and some changes are warranted. For example the Water Framework Directive (WFD) sets environmental quality standards for some, but not all, pesticides. Article 7 provides special protection of water bodies used as sources for drinking water supply, but it is not clear whether the UK will achieve full compliance by 2015. This is a problem for water companies planning investment, because the WFD and Drinking Water Directive remain legally distinct. Further uncertainty arises from the application of Regulation (EC) 1107/2009 and the extent that restricted availability of pesticides will drive changes in agricultural practice and pesticide use.
Open Access
Do charismatic species groups generate more cultural ecosystem service benefits?
(Elsevier, 2017-08-01) McGinlay, James; Parsons, David J.; Morris, Joe; Hubatova, Marie; Graves, Anil; Bradbury, Richard B.; Bullock, James M.
The relationship between nature and cultural ecosystem service (CES) benefits is well accepted but poorly understood, as is the potential role of biodiversity in the relationship. By means of a public questionnaire survey in Wiltshire, UK, the relationship between the presence of a range of common species groups, species group ‘charisma’, group abundance in the landscape, and the benefit that people felt that they derived from the species groups was investigated for a lowland multifunctional landscape. Findings showed that species group charisma influenced the benefit reported by respondents for current abundance levels, and influenced their response to potential increases or decreases in abundance. Respondents reported high levels of benefit from species groups hypothesised to be charismatic (birds, flowering plants, butterflies) and there was high consistency in the pattern of response. Respondents reported less benefit from groups hypothesised to be less charismatic (beetles/bugs, brambles and nettles), the latter response patterns showing much greater variation. These results could be used to promote a more holistic understanding of the value of biodiversity by educating and informing the public so that they derive benefit not just from the charismatic, but also from the everyday, the commonplace and less obviously charismatic species.
Open Access
Environmental assessment of urban mobility: combining life cycle assessment with land-use and transport interaction modelling – application to Lyon (France)
(Elsevier, 2016-09-11) François, C.; Gondran, N.; Nicolas, J-P.; Parsons, David J.
In France, greenhouse gas (GHG) emissions from transport have grown steadily since 1950 and transport is now the main source of emissions. Despite technological improvements, urban sprawl increases the environmental stress due to car use. This study evaluates urban mobility through assessments of the transport system and travel habits, by applying life cycle assessment methods to the results of mobility simulations that were produced by a Land Use and Transport Interactions (LUTI) model. The environmental impacts of four life cycle phases of urban mobility in the Lyon area (exhausts, fuel processing, infrastructure and vehicle life cycle) were estimated through nine indicators (global warming potential, particulate matter emissions, photochemical oxidant emissions, terrestrial acidification, fossil resource depletion, metal depletion, non-renewable energy use, renewable energy use and land occupancy). GHG emissions were estimated to be 3.02 kg CO2-eq inhabitant−1 day−1 , strongly linked to car use, and indirect impacts represented 21% of GHG emissions, which is consistent with previous studies. Combining life cycle assessment (LCA) with a LUTI model allows changes in the vehicle mix and fuel sources combined with demographic shifts to be assessed, and provides environmental perspectives for transport policy makers and urban planners. It can also provide detailed analysis, by allowing levels of emissions that are generated by different categories of households to be differentiated, according to their revenue and location. Public policies can then focus more accurately on the emitters and be assessed from both an environmental and social point of view.
Open Access
Estimation of the greenhouse gas emissions from agricultural pesticide manufacture and use.
(2009-08-01T00:00:00Z) Audsley, Eric; Stacey, K. F.; Parsons, David J.; Williams, Adrian G.
All references to energy for pesticide production in agriculture can be traced back to the original data of Green (1987). The most common method used to derive values for current chemicals is to use the average of each category of active ingredient. However a comparison of the mean and standard deviation of the categories provides little justification for using anything other than the overall average for agrochemicals, both for the total energy used and the breakdown into the different sources of inherent and process energy. However it is likely that using energy requirements derived directly from Green, such as the mean or maximum will generally underestimate for chemicals introduced since 1985.
Open Access
Geostatistical analysis of the spatial distribution of mycotoxin concentration in bulk cereals
(Taylor & Francis, 2009-06-30T00:00:00Z) Rivas Casado, Monica; Parsons, David J.; Weightman, R. M.; Magan, Naresh; Origgi, S.
Deoxynivalenol (DON) and ochratoxin A (OTA) in agricultural commodities present hazards to human and animal health. Bulk lots are routinely sampled for their presence, but it is widely acknowledged that designing sampling plans is particularly problematical because of the heterogeneous distribution of the mycotoxins. Previous studies have not take samples from bulk. Sampling plans are therefore designed on the assumption of random distributions. The objective of this study was to analyse the spatial distribution of DON and OTA in bulk commodities with geostatistics. This study was the first application of geostatistical analysis to data on mycotoxins contamination of bulk commodities. Data sets for DON and OTA in bulk storage were collected from the literature and personal communications, of which only one contained data suitable for geostatistical analysis. This data set represented a 26-tonne truck of wheat with a total of 100 sampled points. The mean concentrations of DON and OTA were 1342 and 0.59 mu g kg(-1), respectively. The results showed that DON presented spatial structure, whilst OTA was randomly distributed in space. This difference between DON and OTA probably reflected the fact that DON is produced in the field, whereas OTA is produced in storage. The presence of spatial structure for DON implies that sampling plans need to consider the location of sample points in addition to the number of points sampled in order to obtain reliable estimates of quantities such as the mean contamination.
Open Access
Guidance for the calculation of carbon brainprints of higher education institution activities
(2011-07-31T00:00:00Z) Parsons, David J.; Chatterton, Julia C.
This document is intended to provide a guide to assessing a carbon brainprint. It was developed as the project case studies were conducted, starting from a set of general principles and becoming more specific. It is guided by the principles used by the IPCC, PAS 2050:2008 and Carbon Trust good practice. However, a carbon brainprint is not an assessment of the life cycle greenhouse gas emission of a specific good or service. In particular, the emphasis is mainly on total changes in emissions, not the functional unit, and general estimates rather than product-specific ones may be required. The guidance covers definitions, basic principles, system boundaries, attribution, uncertainty analysis and the scope and limits of application of the method.
Open Access
Identifying adaptation options and constraints: the role of agronomist knowledge in catchment management strategy
(Springer Science Business Media, 2014-01-31T00:00:00Z) Dolan, Tom; Howsam, Peter; Parsons, David J.; Whelan, M.J.; Varga, Liz
Water suppliers in parts of Europe currently face occasional Drinking Water Directive compliance challenges for a number of pesticide active substances including metal- dehyde, clopyralid and propyzamide. Water Framework Directive (WFD) Article 7 promotes a prevention-led (catchment management) approach to such issues. At the same time, European pesticide legislation is driving reduced active substance availability. In this context, embedding agronomic drivers of pesticide use into catchment management and regulatory decision making processes can help to ensure that water quality problems are addressed at source without imposition of disproportionate cost on either agriculture or potable water suppliers. In this study agronomist knowledge, perception and expectations of current and possible future pesticide use was assessed and the significance of this knowledge to other stakeholders involved with pesticide catchment management was evaluated. This was then used to provide insight into the possible impacts of active substance restrictions and associated adaptation options. For many arable crops, further restrictions on the range of pesticides available may cause increased use of alternatives (with potential for "pollution swapping"). However, in many cases alternatives are not available, too costly or lack a proven track record and other adaptation options may be selected which catchment managers need to be able to anticipate.