Annual variability in the radiocarbon age and source of dissolved CO2 in a peatland stream

Radiocarbon dating has the capacity to significantly improve our understanding of the aquatic carbon cycle. In this study we used a new passive sampler to measure the radiocarbon (14C) and stable carbon (δ13C) isotopic composition of dissolved CO2 for the first time in a peatland stream throughout a complete year (May 2010 – June 2011). The in-stream sampling system collected time-integrated samples of CO2 continuously over approximately one month periods. The rate of CO2 trapping was proportional to independently measured streamwater CO2 concentrations, demonstrating that passive samplers can be used to estimate the time-averaged dissolved CO2 concentration of streamwater. While there was little variation and no clear trend in δ13CO2 values (suggesting a consistent CO2 source), we found a clear temporal pattern in the 14C concentration of dissolved CO2. The 14C age of CO2 varied from 707±35 to 1210±39 years BP, with the youngest CO2 in the autumn and oldest in spring/early summer. Mean stream discharge and 14C content of dissolved CO2 were positively correlated. We suggest that the observed pattern in the 14C content of dissolved CO2 reflects changes in its origin, with older carbon derived from deeper parts of the peat profile contributing proportionally more gaseous carbon during periods of low stream flow

Atmosphere-soil-stream greenhouse gas fluxes from peatlands

The project aims to produce a complete inventory of greenhouse gas fluxes and emissions from a Scottish peatland. Carbon dioxide, methane and nitrous oxide emissions from the land surface (soil and vegetation) to the atmosphere, losses to streamwater and degassing will all be considered. The study is carried out at Auchencorth Moss, Midlothian, with intensive monitoring and measurements being made over a 2-year period, starting March 2006. The site consists of a patchwork of different vegetation communities including areas dominated by Calluna or Juncus, grassy hummocks and hollows and a narrow riparian zone again dominated by Juncus. GHG flux measurements will be made using chambers covering each vegetation type allowing for both a comparison between vegetation types and the subsequent scaling up to catchment level emissions. A flux tower on site provides further data on CO2 net exchange. In addition the concentrations of GHG in the soil are measured using gas permeable tubing. Other land based measurements will include water table depth, soil moisture, soil temperature and soil NO3, NH4 and DOC content. A datalogger is in place adjacent to the stream allowing for almost continuous measurements of stream temperature, conductivity and height; this data along with regular measurements of stream solute and dissolved gas concentrations will be used to estimate both stream gaseous emissions and lateral outputs. Routine measurements of carbon (DOC, DIC, POC, CO2 and CH4) and nitrogen (NO3, NH4, DON, N2O) will also be made along the stream length to measure spatial variability

Novel Circuit Fabrication Techniques for Reduced Environmental Impact

This paper proposes a novel technique for low cost circuit manufacture which it is hoped will offer significant reduction in environmental impact, both in terms of production process, and end of life. The technique is to use a pattern printed on paper by conventional offset lithographic techniques to form interconnection circuitry. Initial research is concentrating on the selection of appropriate conductive inks, and substrate materials. At present, components are attached using conductive adhesives, but the feasibility of placing components during the final printing pass, and using a form of conductive ink to provide the bond, is investigated

Learning New Practices in Small Business: Engagement and Localised Support

Discusses the findings of a study that investigated how the learning of innovative practices might best proceed in small businesses. The recent implementation of the Goods and Service Tax (GST) in Australia presented an opportunity for understanding how small business operatives learned to implement a new practice. The procedures comprised semi¬-structured interviews with 30 small businesses about how they had learned about and implemented the GST. A case study was written about each small business' experience that were verified for their accuracy by each small business. These case studies became the data source. It was found that the small business operatives that appeared to have learned most about the GST were those who were highly engaged in the task of learning about the GST - active learners and also accessed high levels of support from localised sources. A typology comprising dimensions of support needed and engagement by small business operatives was synthesised from the findings and is discussed

Integrated product policy and ecological footprint of electronic products

The ecological footprint (EF) methodology, developed by Wackemagel and Rees (1996), is already a very effective sustainability indicator for the human impact on earth. EFs are calculated by dividing the biologically productive land and sea space of the earth by its population. Thus, EF can be established on a global or other geographic level. In this paper, the authors discuss whether the EF can be brought down to a product level to assess the sustainability of a personal computer (PC). They also used land-space as a single indicator to make results comparable to the current world-average footprint. Recent work in this sector has been done by Buitenkamp and Spapens (1999). This paper extends their research

RRS Discovery Cruise 248, 07 Jul-10 Aug 2000. A multidisciplinary study of the environment and ecology of deep-water coral ecosystems and associated seabed facies and features (The Darwin Mounds, Porcupine Bank and Porcupine Seabight)

RRS Discovery Cruise 248 aimed to carry out a multidisciplinary study of the environment and ecology of deep-water coral ecosystems and associated seabed features in the northeast Atlantic. The study was primarily focused on the Darwin Mounds area, northern Rockall Trough (59° 49’N, 07° 22’W), but also examined a number of sites in the Porcupine Seabight area. The cruise was divided into two legs (Govan-Stornoway, 8 Jul-21 Jul 2000; Stornoway-Southampton, 22 Jul-10 Aug 2000). Leg 1 focused on the ecology of the Darwin Mounds area, with seabed photographic surveys (SOC SHRIMP system), coring (Box and Multiple cores) and trawling (Agassiz) forming the main activities. Leg 2 began with detailed geological investigations of the Darwin Mounds area, concentrating on piston coring and sidescan sonar surveys. Leg 2 concluded with combined ecological and geological studies of carbonate mound sites on the Porcupine Bank and in the Porcupine Seabight. Observations in the Darwin Mounds area confirmed the common occurrence of deep-water corals on these Mounds. The mounds themselves do not appear to be carbonate formations but may be better characterised as sand volcanoes. Numerous xenophyophores were observed in association with the mounds; however, no live specimens were recovered in any of the samples collected. Sidescan sonar images and seabed photography both suggested that the Darwin Mounds area had been subject to considerable commercial trawling with resultant apparent damage to the deep-water coral ecosystems. The various operations undertaken in the Porcupine Seabight area were also successful in imaging giant carbonate mounds and their associated coral communities with both sidescan sonar and seabed photography, and in recovering biological sample material from these areas. In common with the Darwin Mounds area, the observations made suggested that deep-water fishing impacts on coral ecosystems were also evident in this region

Expression regulation of MAO isoforms in monocytic cells in response to Th2 cytokines

Background: Th2-cytokines, such as interleukins-4 and –13 (IL-4, IL-13), have been identified as alternative stimuli of monocytes/macrophages. We have recently profiled the gene-expression pattern of IL-4-teated human peripheral monocytes and found that 15-lipoxygenase-1 (15-LOX1) and monoamine oxidase A (MAO-A) are among the five most strongly upregulated gene products in IL-4-treated cells. Transfection of monocytic cells (U937) with 15-LOX1 also induced MAO-A expression. These data suggested that 15-LOX1 products might play a role in the IL4-induced signaling cascade leading to expression of MAO-A in human monocytes. Material/Methods: To test this hypothesis we incubated wild-type and 15-LOX1-transfected U937 cells with different concentrations of either IL-4 or 15-LOX-products [13S-H(p)ODE, 15S-H(p)ETE] and quantified the expression of 15-LOX1, MAO-A, and MAO-B by activity assays and real-time RT-PCR. Results: Wild-type U937 cells express neither MAO-A nor MAO-B, but after three days of IL4 treatment, MAO-A mRNA was detected. A similar isoform-specific expression of MAO-A mRNA was observed when U937 cells were transfected with 15-LOX1 or when the cells were incubated with primary 15-LOX1 products (hydroperoxy fatty acids) or H2O2. In contrast, the corresponding hydroxy fatty acids were ineffective. Conclusions: These data indicate that increased intracellular peroxide concentrations (oxidative stress) induce MAO-A expression in monocytes/macrophages, which normally do not express the enzyme. Our findings also suggest that IL-4-induced upregulation of MAO-A expression in human peripheral monocytes may proceed via 15-LOX1-dependent and 15-LOX1-independent pathways. The biological role of MAO-A expression for monocyte function is discussed

An investigation of the possible extent of the re-spending rebound effect in the sphere of consumer products

A key method used to reduce the environmental impact of a product is to make it more energy efficient. Previous studies have found that the potential benefits from improved efficiency are often at least partially negated by increased use of the product. This is called the ‘rebound effect’. The logical extension of this theory is to consider what happens when efficiency savings from one product lead to the purchase of, or greater use of, another. This paper considers this issue, called the ‘re-spending effect’, and uses the illustration of the purchase of an energy-efficient fridge-freezer and the installation of a high-efficiency domestic boiler to demonstrate the loss of up to 27% of the potential environmental benefit when monetary savings are spent on other products and services. The paper concludes that the development of high value, long-lasting, low resource-use products should be encouraged as a way of counteracting the ‘re-spending’ effect thus producing an overall reduction in energy use and its attendant environmental damage

Effective models of employment-based training

Evolving models of employment-based training (EBT) are responding to skill shortages and the need to develop technical skills at a level higher than a certificate III—the benchmark qualification level considered by many as the minimum for ensuring sustainable job outcomes (Stanwick 2004). This research explored a variety of current employment-based training models and proposed five enhancements for higher-level qualifications. These changes concentrate on maintaining a balance of learning experiences between educational institutions and the workplace. The project was based around case studies in process manufacturing and child care. Thirty-three individuals, representing employers, employees/apprentices, vocational education and training (VET) providers, industry bodies and training package developers were interviewed. The issues and views expressed by those interviewed from both industries were consistent with what was found in the literature review. Current models of employment-based training can usefully be grouped as: two forms of 'fast-tracking' options in a formal apprenticeship model, especially at certificate III level, to address immediate skills shortages. These are accelerated progression models (shorter durations linked to a truly competency-based approach) and intensive up-front training, followed by work-based learning to ensure immediate productivity of the learner in the workplace higher-level VET qualifications gained either through an apprenticeship or by undertaking a vocational course the design of new skill sets/qualifications at various levels of the Australian Qualifications Framework (AQF) alternative provisions for young people. Although these models continue to make a significant contribution to the skilling of the Australian workforce, their full potential is limited by certain persistent issues. These include inconsistent regulatory arrangements, non-compliance by employers and registered training organisations, poor audit processes, variations in the interpretation and practice of competency-based training, and wages and awards. These various factors mean poor completion rates and losses for individuals, employers, governments and other stakeholders. Recent changes in policy direction are attempting to address some of these issues and simultaneously increase interest and growth in the uptake of employment-based training. Any new models of employment-based training should address existing problems, as well as take into account the emerging needs of industry for skilled labour. The design of the models must also address an ageing workforce and allow flexible entry points for all age groups. Furthermore, future employment-based training models also need to keep pace with how work is organised in an environment characterised by increased competition, outsourcing, casualisation and an emphasis on specialisation and innovation. What is becoming apparent is the need for a compendium of models, rather than a 'one size fits all' approach

Isolating LCDs at end-of-life using active disassembly technology: A feasibility study

The European Union draft Waste Electrical and Electronic Equipment (WEEE) directive calls for the removal and separate treatment of liquid crystal displays (LCD). This aspect of the legislation will potentially have an important impact upon the future `End of Life' (EoL) processing of much WEEE. Active Disassembly using Smart Materials (ADSM) has been proven to have applicability in self-dismantling, nondestructive and rapid disassembly of small electronic products. This paper investigates the technical feasibility of removing LCD screens from IT communication products using ASDM technology. In this paper an option is suggested to cleanly separate LCD screens from printed circuit boards, utilizing an LCD bracket made from `shape memory polymer'. The case study products employed are Nokia Japanese J-Phones. Demonstration experiments with initial results are presented, and future developments discussed. SMB glass transformation temperatures (Tg) and time efficiency in disassembly are considered