Bioremediation of diesel contaminated soils : an investigation into the effects of biosurfactant and organic matter amendments

The aim of this study was to investigate the effects of biosurfactants and organic matter amendments on the bioremediation of diesel contaminated soil. Two strains of Pseudomonas aeruginosa with the ability to produce biosurfactant were isolated from a water and soil sample in Co. Sligo. The first strain, Isolate A, produced a biosurfactant which contained four rhamnose containing compounds, when grown in proteose peptone glucose ammonium salts medium with glucose as the carbon source. Two of the components were identified as rhamnolipid 1 and 2 whilst the other two components were unidentified. The second strain, Isolate GO, when grown in similar conditions produced a biosurfactant which contained only rhamnolipid 2. The type of aeration system used had a significant effect on the abiotic removal of diesel from soil. Forced aeration at a rate of 120L 02/kg soil/ hour resulted in the greatest removal. Over a 112 day incubation period this type o f aeration resulted in the removal o f 48% o f total hexane extractable material. In relation to bioremediation of the diesel contaminated sandy soil, amending the soil with two inorganic nutrients, KH2PO4 and NÜ4N03, significantly enhanced the removal of diesel, especially the «- alkanes, when compared to an unamended control. The biosurfactant from Isolate A and a biosurfactant produced by Pseudomonas aeruginosa NCIMB 8628 (a known biosurfactant producer), when applied at a concentration of three times their critical micelle concentration, had a neutral effect on the biodégradation o f diesel contaminated sandy soil, even in the presence o f inorganic nutrients. It was deduced that the main reason for this neutral effect was because they were both readily biodegraded by the indigenous microorganisms. The most significant removal of diesel occurred when the soils were amended with two organic materials plus the inorganic nutrients. Amendment of the diesel contaminated soil with spent brewery grain (SBG) removed significantly more diesel than amendment with dried molassed sugar beet pulp (DMSBP). After a 108 day incubation period, amendment of the diesel contaminated soil with DMSBP plus inorganic nutrients and SBG plus inorganic nutrients resulted in 72 and 89% removal of diesel range organics (DRO), in comparison to 41% removal of DRO in an inorganic nutrient amended control. The first order kinetic model described the degradation of the different diesel components with high correlation and was used to calculate Vi lives. The V2 life, of the total «-alkanes in the diesel was reduced from 40 days in the control to 8.5 and 5.1 days in the presence of DMSBP and SBG, respectively. The V2 life o f the unresolved complex mixture (UCM) in the diesel contaminated soil was also significantly reduced in the presence o f the two organics. DMSBP and SBG addition reduced UCM V2 life to 86 and 43 days, respectively, compared to 153 days in the control. The component of diesel whose removal was enhanced the greatest through the organic material amendments was the isoprenoid, pristane, a compound which until recently was thought to be nonbiodegradable and was used as an inert biomarker in oil degradation studies. The V2 life of pristane was reduced from 533 days in the nutrient amended control to 49.5 and 19.5 days in DMSBP and SBG amended soils. These results indicate that the addition o f the DMSBP and SBG to diesel contaminated soil stimulated diesel biodégradation, probably by enhancing the indigenous diesel degrading microbial population to degrade diesel hydrocarbons, whilst the addition o f biosurfactants had no enhanced effect on the bioremediation process.

The Irish pub as a third place : a sociological exploration of people, place and identity

There is considerable interest in alcohol in Irish society, yet minimal sociologcial understanding of its consumption, particularly of the sites where most drinking occurs: the country's 8750 pubs. Despite widespread public discussions on the role of the pub, there is scant social science evidence to better inform debate. Pubs are central to Irish community and are key sites of social interaction. American sociologist Ray Oldenburg has argued that "third places" (neither workplace nor home) are crucial to the maintenance of the community and the enhancement of social capital. According to Oldenburg, the role of the third place in the community is to provide continuity, regularity, a sense of place - all of which conceptually contribute to the construction of the self, the projection of the self within the public sphere, the distribution of social capital and the generation of a collective identity. The pub is the archetypal third place, but Oldenburg is concerned that modern pubs are less able to provide this vital function. Social scientists have suggested that community is in a state of fragmentation and decline due to changes in modes of social interaction and a decrease in shared spaces, resulting in a weakened connection to place. Community without propinquity has been characterised by social alienation, fragmentation and what Oldenburg refers to as the "problem of place" (13). Third places, and thus the Irish pub, have been particularly affected. In order to increase the sociological knowledge of the pub in Ireland, this project critically engages with the pub to assess the importance that public drinking houses have in the everyday. Moreover, this research sets out to investigate the people/place relationship using the pub as an investigative lens and examine the ways in which people shape place, place shapes people and how that relationship is implicated in the construction of irish identities. Furthermore, this is also an articulation of a cultural shift within Ireland and Irish places whose effects are deep and multi-layered. This project aims to explore the development of the contemporary geography of identity as the irish pub as a third place is transformed or disappears from the social landscape.

An investigation into the temperature distribution resulting from cutting of compact bone using a reciprocating bone saw

Surgical procedures such as osteotomy and hip replacement involve the cutting of bone with the aid of various manual and powered cutting instruments including manual and powered bone saws. The basic mechanics of bone sawing processes are consistent with most other material sawing processes such as for wood or metal. Frictional rubbing between the blade of the saw and the bone results in the generation of localised heating of the cut bone. Research studies have been carried out which consider the design of the bone saw which deals with specifics of the saw teeth geometry and research which examines the effect of drilling operations on heating of the bone has shown that elevated temperatures will occur from frictional overheating. This overheating in localised areas is known to have an impact on the rate of healing of the bone post operation and the sharpness life of the blade. The purpose of this study was to measure the temperature at three zones at fixed intervals of 3mm, 6mm, and 9mm away from the cutting zone. It should be noted that it was the first time that this measurement technique was used to measure the temperature gradient through the bone specimen thereby establishing the extent to which clinicians are experiencing thermal injury during sawing of bone while using a reciprocating saw. The effect of various cutting feed rate on temperature elevation was also investigated in this research. The results showed that there will be a region of bone at least 9mm either side of the cutting blade experiencing thermal injury as temperatures in this region exceeded the threshold temperature of 44°C for necrosis (cell death).

A review of the development of regional sludge treatment centres and a baseline characterisation of Irish sewage sludges

This Study assessed the development of sludge treatment and reuse policy since the original 1993 National Sludge Strategy Report (Weston-FTA, 1993). A review of the 48 sludge treatment centres, current wastewater treatment systems and current or planned sludge treatment and reuse systems was carried out Sludges from all Regional Sludge Treatment Centres (areas) were characterised through analysis of selected parameters. There have been many changes to the original policy, as a result of boundary reviews, delays in developing sludge management plans, development in technology and changes in tendering policy, most notably a move to design-build-operate (DBO) projects. As a result, there are now 35 designated Hub Centres. Only 5 of the Hub Centres are producing Class A Biosolids. These are Ringsend, Killamey, Carlow, Navan and Osberstown. Ringsend is the only Hub Centre that is fully operational, treating sludge from surrounding regions by Thermal Drying. Killamey is producing Class A Biosolids using Autothermal Thermophilic Aerobic Digestion (ATAD) but is not, as yet, treating imported sludge. The remaining three plants are producing Class A Biosolids using Alkaline Stabilisation. Anaerobic Digestion with post pasteurisation is the most common form of sludge treatment, with 11 Hub Centres proposing to use it. One plant is using ATAD, two intend to use Alkaline Stabilisation, seven have selected Thermal Drying and three have selected Composting. While the remaining plants have not decided which sludge treatment to select, this is because of incomplete Sludge Management Plans and on DBO contracts. Analysis of sludges from the Hub Centres showed that all Irish sewage sludge is safe for agricultural reuse as defined by the Waste Management Regulations {Use of Sewage Sludge in Agriculture) (S.I. 267/2001), providing that a nutrient management plan is taken into consideration and that the soil limits of the 1998 (S.I. 148/1998) Waste Management Regulations are not exceeded.

A comparative study of the physical, chemical and microbiological status of soils, as influenced by conventional and reduced tillage

Historically, shifts to reduced and no-tillage management for production of crops were fostered by needs to decrease soil erosion and loss of organic matter, reduce fuel and labour costs and conserve soil water, as compared with conventional fallow tillage management. Recent interest in maintaining soil quality has been stimulated by a renewed awareness of the importance of soil condition to both the sustainability of agricultural production systems and environmental quality (Doran and Parkin, 1996). The aim of this project was to determine the impact on the physical, chemical and microbiological status of the soil of conventional and reduced tillage. It has been suggested that the reduced soil disturbance associated with the tine cultivator improves soil structure, increases nutrient content in the top 10cm of soil, increases microbial activity and improves physical characteristics. From this study it was determined that the environmental benefits linked to reduced tillage in literature, did not develop in the first two years of this programmes implementation. The results of this study determined that soil nutrients did not increase in concentration in the top 10 cm of soil under reduced cultivation. The only exception was exchangeable potassium. As potassium is not a mobile nutrient its movement is dependent on soil disturbance, therefore under reduced cultivation its concentration was allowed to accumulate in the upper horizon of the soil profile. Microbial activity was greater in the conventionally tilled treatments, as determined by total aerobic bacterial numbers. This could be due to the increased rates of soil aeration in this treatment. Numbers of aerobic bacteria were greater in the conventional tillage treatments at both incubation temperatures of 22 and 32° C. The physical characteristics of the soil determined, indicate that below the depth of soil cultivation, cone penetration resistance increases. Therefore the reduced cultivation treatments would be more prone to soil compaction, higher in the soil profile.

An evaluation of septic tank effluent movement in soil and groundwater systems

Recent studies have shown that septic tank systems are a major source of groundwater pollution. Many public health workers feel that the most cri^cal aspect of the use of septic tanks as a means of sewage disposal is the contamination of private water wells with attendant human health hazards. In this study the movement and attenuation of septic tank effluents in a range of soil/overburden types and hydrogeological situations was investigated. The suitability of a number of chemical and biological tracer materials to monitor the movement of septic tank effluent constituents to groundwater sources was also examined. The investigation was divided into three separate but inteiTelated sections. In the first section of the study the movement of septic tank effluent from two soil treatment systems was investigated by direct measurements of soil nutrient concentrations and enteric bacterial numbers in the soil beneath and downgradient of the test systems. Two sites with different soil types and hydrogeological characteristics were used. The results indicated that the attenuation of the effluent in both of the treatment systems was incomplete. Migration of nitrate, ammonium, phosphate and fecal bacteria to a depth of 50 cm beneath the inverts of the distribution tiles was demonstrated on all sampling occasions. The lateral migration of the pollutants was less pronounced, although on occasions high nutrients levels and fecal bacterial numbers were detected at a lateral distance of 4.0 m downgradient of the test systems. There was evidence that the degree and extent of effluent migration was increased after periods of heavy or prolonged rainfall when the attenuating properties of the treatment systems were reduced as a result of saturation of the soil. The second part of the study examined the contamination of groundwaters downgradient of septic tank soil treatment systems. Three test sites were used in the investigation. The sites were chosen because of differences in the thicknesses and nature of the unsaturated zone available for effluent attenuation at each of the locations. A series of groundwater monitoring boreholes were installed downgradient of the test systems at each of the sites and these were sampled regularly to assess the efficiency of the overburden material in reducing the polluting potential of the wastewater. Effluent attenuation in the septic tank treatment systems was shown to be incomplete, resulting in chemical and microbiological contamination of the groundwaters downgradient of the systems. The nature and severity of groundwater contamination was dependent on the composition and thickness of the unsaturated zone and the extent of weathering in the underlying saturated bedrock. The movement of septic tank effluent through soil/overburdens to groundwater sources was investigated by adding a range of chemical and biological tracer materials to the three septic tank systems used in section two of the study. The results demonstrated that a single tracer type cannot be used to accurately monitor the movement of all effluent constituents through soils to groundwater. The combined use of lithium bromide and endospores of Bacillus globigii was found to give an accurate indication of the movement of both the chemical and biological effluent constituents.

A comparative analysis of sustainable tourism, planning and development between Sligo and Donegal County Councils

Sustainable Development requires appropriate and continuous planning and management of economic, socio cultural and environmental resources. Tourism planning calls for continuous collaboration among tourism agencies, local authorities and local communities for success of the industry. While evidence suggests that tourism planning has been extensively documented, it is apparent that Donegal and Sligo County Councils have, in some cases failed to adequately address the significance of planning of the tourism industry for the North West of Ireland. This was investigated through interviews with chief planners of Donegal and Sligo county councils and was conducted in conjunction with the analysis of county development plans; which were formulated by both organisations involved in this study. Evidence suggests that although tourism is extensively documented by Donegal and Sligo county councils, neither of the two local authorities have developed implementation strategies to facilitate the promotion of sustainable tourism development. This research compares and analyses Donegal and Sligo county councils and how they plan for sustainable tourism development. It outlines the role of the county councils in relation to tourism planning and how Donegal and Sligo compare in how they plan for such a significant industry in the North West o f Ireland. It highlights the importance of implementation tools and methods and offers future directions that can assist in the development of sustainable tourism.

Training and development in Irish technology companies

The sustained economic growth that has been experienced in the Irish economy in recent years has relied, to a large extent, on the contribution and performance of those industry sectors that possess the ability to provide high-value-added products and services to domestic and international markets. One such contributor has been the Technology sector. However, the performance of this sector relies upon the availability of the necessary capabilities and competencies for Technology companies to remain competitive. The Expert Group on Future Skills Needs have forecasted future skills shortages in this sector. The purpose of this research has been to examine the extent to which Irish Technology companies are taking measures to meet changing skills requirements, through training and development interventions. Survey research methods (in the form of a mail questionnaire, supported by a Web-based questionnaire) have been used to collect information on the expenditure on, and approach to, training and development in these companies, in addition to the methods, techniques and tools/aids that are used to support the delivery of these activities. The contribution of Government intervention has also been examined. The conclusions have been varied. When the activities of the responding companies are considered in isolation, the picture to emerge is primarily positive. Although the expenditure on training and development is slightly lower than that indicated in previous studies, the results vary by company size. Technical employees are clearly the key focus of training provision, while Senior Managers and Directors, Clerical and Administrative staff and Manual workers are a great deal more neglected in training provision. Expenditure on, and use of, computer-based training methods is high, as is the use of most of the specified techniques for facilitating learning. However, when one considers the extent to which external support (in the form of Government interventions and cooperation with other companies and with education and training providers) is integrated into the overall training practices of these companies, significant gaps in practice are identified. The thesis concludes by providing a framework to guide future training and development practices in the Technology sector.

Silent voices : the recreational needs of disabled young people : an emancipatory approach

The recreational needs of young people with.disabilities in Sligo county were examined using an emancipatory approach that provided an accurate reflection on the perspectives of the disabled young people. The aim of this study included a comparison of access to and attitudes towards leisure activities as between disabled and non-disabled young people in the Sligo area. The hypothesis set out by the researcher was the expectation that findings would include a degree of disadvantage in access and participation in leisure activities for young people with disabilities vis a vis their counterparts. The way in which this was tested was by focus groups and interviews. This hypothesis was adequately proven along with an in-depth range of recommendations for improvement that were made by participants. The study’s emancipatory research methods ensured that the voice of the participants was heard regarding their recreational needs and the disabling barriers that needed to be removed.

The assessment, management and ecological significance of Irish hedgerows

The vast network of hedges in Ireland provide habitats of great importance to the wildlife of the country, yet surprisingly enough, only very limited survey work has been carried out on our hedgerows in the past. Now with the implementation of the new Rural Environmental Protection Scheme, farmers will be paid to manage their hedgerows in such a way as to make them into increasingly attractive wildlife habitats. However, hedgerow management expertise seems to be somewhat lacking in Ireland and we must draw upon the knowledge of our neighbours in the E.U. where quite an amount of research has been carried out on this subject. The aim of this study is to present the relevant aspects of the research for the benefit of the people who will be involved in the administration of the Rural Environmental Protection Scheme and to anyone else involved in hedgerow management.

Tourism education in Ireland : an analysis of the provision of third level tourism education in Ireland focusing on the needs of the public, private and voluntary sectors

Tourism education in Ireland has witnessed a transformation within the last four decades since CERT introduced the first fundamentals of training in the 1960’s. An analysis of the provision of tourism education in Ireland, focusing on the needs of the public, private and voluntary sectors was the main focus of this study and concentrates mainly on third level provision of tourism education within the island of Ireland. The study examines the role of tourism education in Ireland, establishing any current or emerging trends in third level tourism provision. It identifies and analyses the main stakeholders in the public, private and voluntary sectors and investigates if any requirements exist in the provision of third level education. The multi-faceted nature of the tourism industry has resulted in the provision of a diverse range of educational courses. As a result of this diversity, a question hangs over the status of tourism as a professional discipline within itself. Other issues identified through this study are the over provision of tourism courses and the current and future disparity within tourism education. The qualitative nature of the research involved questioning of major stakeholders and educators who influence tourism education provision and developing an overview of the current status of tourism education provision in Ireland identifying the present needs of each sector. Finally several strategies are suggested which may enhance third level tourism education in the future.

The appraisal of mesophilic anaerobic digestion and thermophilic aerobic digestion in the treatment of municipal sludge in Ireland

It has been well documented that the optimum feedstock for anaerobic digesters consists of readily biodegradable compounds, as found in primary sludge or even a mixed substrate of primary and excess activated sludge. Due to the requirements of the Urban Wastewater Treatment Plant Directive of 1991, the quantities of secondary sludge generated is set to increase substantially. A pilot scale study was undertaken to evaluate the performance of both Mesophilic Anaerobic Digestion and Thermophilic Aerobic digestion in the treatment of secondary sludge. The results indicated that the anaerobic pilot scale digester achieved a greater solids destruction than the aerobic pilot plant averaging at 28% T.S. removal verses 20% for the aerobic digester, despite the fact that secondary sludge is the optimum feedstock for aerobic digestion. This can, however, be attributed to the greater biomass yield experienced with aerobic systems, and to the absence of Autothermal conditions. At present, the traditional technique of Mesophilic Anaerobic Digestion is in widespread application throughout Ireland, for the stabilisation of sewage sludge. There is only one Autothermal Thermophilic Aerobic Digester at present situated in Killarney, Co. Kerry. A further objectives of the study was to compare full-scale applications of Mesophilic Anaerobic Digestion to ATAD. Two Sludge Treatment plants, situated in Co. Kerry, were used for this purpose, and were assessed mainly under the following headings; process stability, solids reduction on average, the ATAD plant in Killarney has the advantage of producing a “Class A” Biosolid in terms of pathogen reduction, and can effectively treat double the quantity of sludge. In addition, economically the ATAD plant is cheaper to run, costing €190 / t.d.s verses €211 / t.d.s. for the anaerobic digester in Tralee. An overview of additional operational Anaerobic Digestion Plants throughout Ireland is also presented.

Automating the testing process of image processing algorithms

As digital imaging processing techniques become increasingly used in a broad range of consumer applications, the critical need to evaluate algorithm performance has become recognised by developers as an area of vital importance. With digital image processing algorithms now playing a greater role in security and protection applications, it is of crucial importance that we are able to empirically study their performance. Apart from the field of biometrics little emphasis has been put on algorithm performance evaluation until now and where evaluation has taken place, it has been carried out in a somewhat cumbersome and unsystematic fashion, without any standardised approach. This paper presents a comprehensive testing methodology and framework aimed towards automating the evaluation of image processing algorithms. Ultimately, the test framework aims to shorten the algorithm development life cycle by helping to identify algorithm performance problems quickly and more efficiently.

A comparison of environmental licensing systems in operation in the wood panel manufacturing industry in the Northern Hemisphere

The objective of this thesis is to compare and contrast environmental licensing systems, for the wood panel industry, in a number of countries in order to determine which system is the best from an environmental and economic point of view. The thesis also examines the impact which government can have on industry and the type of licensing system in operation in a country. Initially, the thesis investigates the origins of the various environmental licensing systems which are in operation in Ireland, Scotland, Wales, France, USA and Canada. It then examines the Environmental Agencies which control and supervise industry in these countries. The impact which the type of government (i.e. unitary or federal) in charge in any particular country has on industry and the Regulatory Agency in that country is then described. Most of the mills in the thesis make a product called OSB (Oriented Strand Board) and the manufacturing process is briefly described in order to understand where the various emissions are generated. The main body of the thesis examines a number of environmental parameters which have emission limit values in the licenses examined, although not all of these parameters have emission limit values in all of the licenses. All of these parameters are used as indicators of the potential impact which the mill can have on the environment. They have been set at specific levels by the Environmental Agencies in the individual countries to control the impact of the mill. Following on from this, the two main types of air pollution control equipment (WESPs and RTOs) are described in regard to their function and capabilities. The mill licenses are then presented in the form of results tables which compare air results and water results separately. This is due to the fact that the most significant emission from this type of industry is to air. A matrix system is used to compare the licenses so that the comparison can be as objective as possible. The discussion examines all of the elements previously described and from this it was concluded that the IPC licensing system is the best from an environmental and economic point of view. It is a much more expensive system to operate than the other systems examined, but it is much more comprehensive and looks at the mill as a whole rather than fragmenting it. It was also seen that the type of environmental licensing system which is in place in a country can play a role in the locating of an industry as certain systems were seen to have more stringent standards attached to them. The type of standard in place in a country is in turn influenced by the type of government which is in place in that country.

Transfer of radionuclides from soil to vegetation in selected Irish ecosystems

This thesis details the findings of a study relating the transfer of 238U, 228Ra (232Th), 226Ra, and 137Cs from soil to vegetation in an Atlantic blanket bog, upland blanket bog and semi-natural grassland situated along the north-west coast of Ireland. The results of this study provide information on the uptake of these radionuclides by the indigenous vegetation found present in these ecosystems. The ecosystems chosen are internationally recognizable ecosystems and provide a wide variety of vegetation species and contrasting soil physiochemical properties which allow the influence of these parameters on radionuclide uptake to be assessed. The levels of radionuclides in the soil and vegetation were measured using gamma spectrometry, alpha spectrometry and ICP-MS. The nutrient status of the vegetation and soil physiochemical properties were measured using atomic absorption, flame photometry and other analytical techniques. The results of the study indicate that the uptake of 238U and 228Ra (232Th) by vegetation from all three ecosystems was negligible as the levels in all vegetation was below the limits of detection for the methods used in this study. These results appear to indicate that the vegetation studied do not possess the ability to accumulate significant levels of these radionuclides however this assumption cannot be upheld in the case of the Atlantic blanket bog as the levels in the soil of this ecosystem were too low for detection. Similar results were obtained for 226Ra uptake in both the Atlantic blanket bog and grassland for all vegetation with the exception of H. lanatus from the grassland ecosystem. Radium-226 uptake in upland blanket bog was higher and was detectable in the majority of vegetation indigenous to this ecosystem. Transfer factor values ranged from 0.07 to 2.35 and the TF values for E. tetralix were significantly higher than all other vegetation studied. This species of heather demonstrated the ability to accumulate 226Ra to a greater extent than all other vegetation. The uptake of 226Ra by upland blanket bog vegetation appears to be significantly influenced by a range of soil physiochemical properties. The nutrient status of the vegetation, in particular the calcium content in the vegetation appears to have a negative impact on the uptake of this radionuclide. Potassium-40 was detectable in all vegetation present in the three ecosystems and the levels in the grassland soil were significantly higher than the levels in both bogland soils. Transfer factor values for Atlantic blanket bog vegetation ranged from 0.9 to 13 .8 and were significantly higher in E. vaginatum in comparison to C. vulgaris. Potassium-40 TF values for upland blanket bog vegetation on average ranged from 1.4 for C. vulgaris (stems) to 5.2 for E. vaginatum and were statistically similar for all species of vegetation. Transfer factor values for grassland vegetation ranged from 0.7 to 3.8 and were also statistically similar for all species of vegetation indicating that the transfer of 40K to vegetation within the upland bog and grassland ecosystem is not dependent on plant species. Comparisons of 40K TF values for all three ecosystems indicate that the uptake in E. vaginatum from the Atlantic blanket bog was statistically higher than all other vegetation studied. This appears to indicate that E. vaginatum has the ability to accumulate 40K, however, this species of vegetation was also present in the upland blanket and did not demonstrate the same behaviour. The uptake of 40K by vegetation from all three ecosystems was significantly affected by a range of soil physiochemical properties and in some cases the results were contradictory in nature possibly indicating that the affect of these parameters on 40K uptake is species dependent. The most obvious trend in the data was the influence of soil CEC and magnesium levels in vegetation on 40K TF values. A positive correlation was apparent between the CEC of the soil and 40K uptake in vegetation from both the Atlantic blanket bog and grassland ecosystem. A similar trend was apparent between magnesium levels in vegetation and 40K TF values for the upland blanket bog and grassland vegetation. Caesium-13 7 levels were found to be significantly higher in the two bogland soils in comparison to the grassland soil and levels of 137Cs decreased with increasing soil depth. Transfer factor values for Atlantic blanket bog vegetation ranged from 1.9 to 9.6 and TF values were significantly higher in the leaves o f C. vulgaris in comparison to all other vegetation from this ecosystem. Caesium-13 7 TF values for the upland blanket bog vegetation on average ranged from 0.29 for E. tetralix to 1.6 for C. vulgaris. Uptake by the leaves of C. vulgaris was significantly higher than all other vegetation present thereby supporting the trend found within the Atlantic blanket bog vegetation. These results appear to indicate that the leaves of C. vulgaris have the ability to accumulate significant quantities of 137Cs and also that the uptake of 137Cs by this vegetation is dependent on plant compartment as the stems of this vegetation contained significantly lower levels than the leaves in both ecosystems. The uptake of 137Cs by grassland vegetation was very low and was only detectable in a fraction of the vegetation sampled. Caesium-137 TF values for grassland vegetation were in general lower than 0.02. The impact of soil physiochemical properties and nutrient status of vegetation on 137Cs uptake by vegetation appears to be complex and in some cases contradictory. The most apparent trend in the data was the positive influence of vegetation nutrients on 137Cs uptake in particular the magnesium levels present in the vegetation and to a lesser extent the calcium levels present. The results in general indicate that the uptake of 226Ra, 40K and 137Cs by the chosen vegetation is varied and complex and is significantly dependent on the species of vegetation, soil radionuclide concentration, soil physiochemical properties and the nutrient status of the vegetation.