Substrate-dependent bacterivory by intertidal benthic copepods

The trophic importance of bacteria to harpacticoid copepods in intertidal areas remains poorly understood, and so do the mechanisms of bacterial feeding. It is, for instance, unclear whether harpacticoids directly target bacterial cells or merely co-ingest them with substrates to which bacterial cells may be attached. Here, we investigate bacterial uptake and substrate requirement for four mud intertidal species (Microarthridion littorale, Platychelipus littoralis, Delavalia palustris and Nannopus palustris) by means of ¹³C-labeled bacteria and biomarker fatty acids (FA). Bacterial uptake strongly depended on grazing on a primary food source but bacterial ingestion rates were low, and no clear indication of copepods directly targeting bacteria was found. Delavalia was the only species that accumulated bacteria-derived FA and gained in polyunsaturated FA (PUFA) probably through bioconversion of bacteria-derived FA. In general, however, our results suggest that bacteria represent a relatively minor and low-quality food for intertidal harpacticoid copepods.     

Conserving Mangrove Ecosystems in the Philippines: Transcending Disciplinary and Institutional Borders

Humans are rapidly depleting critical ecosystems and the life support functions they provide, increasing the urgency of developing effective conservation tools. Using a case study of the conversion of mangrove ecosystems to shrimp aquaculture, this article describes an effort to develop a transdisciplinary, transinstitutional approach to conservation that simultaneously trains future generations of environmental problem solvers. We worked in close collaboration with academics, non-government organizations, local government and local communities to organize a workshop in Puerto Princesa, Palawan, Philippines. The primary objectives of the workshop were to: (1) train participants in the basic principles of ecological economics and its goals of sustainable scale, just distribution and efficient allocation; (2) learn from local community stakeholders and participating scientists about the problems surrounding conversion of mangrove ecosystems to shrimp aquaculture; (3) draw on the skills and knowledge of all participants to develop potential solutions to the problem; and (4) communicate results to those with the power and authority to act on them. We found that the economic and ecological benefits of intact mangroves outweigh the returns to aquaculture. Perversely, however, private property rights to mangrove ecosystems favor inefficient, unjust and unsustainable allocation of the resource—a tragedy of the non-commons. We presented the workshop results to the press and local government, which shut down the aquaculture ponds to conserve the threatened ecosystem. Effective communication to appropriate audiences was essential for transforming research into action. Our approach is promising and can be readily applied to conservation research and advocacy projects worldwide, but should be improved through adaptive management—practitioners must continually build on those elements that work and discard or improve those that fail.     

A field trial to assess the performance of CO2-supersaturated water injection for residual volatile LNAPL recovery

A pilot scale field trial was conducted to evaluate the recovery of volatile, light non-aqueous phase liquids (LNAPLs) using a novel remediation method termed supersaturated water injection (SWI). SWI uses a patented technology to efficiently dissolve high concentrations of CO₂ into water at elevated pressures. This water is injected into the subsurface resulting in the nucleation of CO₂ bubbles at and away from the injection point. The nucleating bubbles coalesce, rise and volatilize residual LNAPL ganglia. In this study, an LNAPL composed of 103 kg of volatile pentane and hexane, and 30 kg of non-volatile Soltrol was emplaced below the water table at residual saturation. The SWI technology removed 78% of the pentane and 50% of the less volatile hexane. Contaminant mass was still being removed when the system was shut down for practical reasons. The mass removed is comparable to that expected for air sparging but a much smaller volume of gas was injected using the SWI system.     

Security risks in nuclear waste management: Exceptionalism,opaqueness and vulnerability

This paper analyses some potential security risks, concerning terrorism or more mundane forms of crime, such as fraud, in management of nuclear waste using a PEST scan (of political, economic, social and technical issues) and some insights of criminologists on crime prevention. Nuclear waste arises as spent fuel from ongoing energy generation or other nuclear operations, operational contamination or emissions, and decommissioning of obsolescent facilities. In international and EU political contexts, nuclear waste management is a sensitive issue, regulated specifically as part of the nuclear industry as well as in terms of hazardous waste policies. The industry involves state, commercial and mixed public–private bodies. The social and cultural dimensions – risk, uncertainty, and future generations – resonate more deeply here than in any other aspect of waste management. The paper argues that certain tendencies in regulation of the industry, claimed to be justified on security grounds, are decreasing transparency and veracity of reporting, opening up invisible spaces for management frauds, and in doing allowing a culture of impunity in which more serious criminal or terrorist risks could arise. What is needed is analysis of this ‘exceptional’ industry in terms of the normal cannons of risk assessment – a task that this paper begins.     

A proactive approach to human error detection and identification in aviation and air traffic control

In recent years, there has been a realization that total elimination of human error may be difficult to achieve. A further reduction of accidents will require a better understanding of how practitioners manage their errors in ways that consequences are contained or mitigated. With this goal in mind, the present study has set out to propose a framework of cognitive strategies in error detection that would make human performance resilient to changes in work demands. The literature regarded error detection as a spontaneous process that occurs either while an action is executed (action-based detection) or after action feedback (outcome-based detection). To help practitioners maintain a state of mindfulness and introspection, this study proposes several cognitive strategies such as, rehearsing tasks for future execution, bringing into conscious attention routine tasks, seeing how trajectories change over time, and cross-checking data for reliability. Two further detection mechanisms are proposed at the situation assessment and planning stages of performance. Awareness-based detection may include revising a model of the situation, finding hidden assumptions, and testing the plausibility of assumptions. Planning-based detection addresses issues such as, identifying uncertainties in a plan, thinking out possible errors, and deciding when and how often to review task progress. Finally, several attitudinal factors and team factors are presented that affect the processes of error detection and identification. The cognitive strategies in error detection together with the attitudinal and team factors constitute a framework for designing the content of error management training.     

Co-occurrence of three types of egg policing in the Norwegian wasp <Emphasis Type="Italic">Dolichovespula norwegica</Emphasis>

In insect societies, workers often try to challenge the reproductive monopoly of the queen by laying their own eggs. Successful worker reproduction, however, is frequently prevented by queen policing or worker policing, whereby either the mother queen or non-reproductive workers selectively kill worker-laid eggs. Recently, a third mechanism—“selfish” worker policing—has also been described in which the workers selectively police worker-laid eggs but also lay eggs themselves. Here, we present results from the monogynous wasp Dolichovespula norwegica, which show that all three kinds of policing—queen policing, worker policing and “selfish” worker policing—co-occur. The net effect of these three kinds of policing collectively favoured the queen’s reproduction, as within 1 day 44% of the worker-laid eggs versus only 8% of the queen-laid eggs were eaten. Of the worker-laid eggs that were killed by workers, approximately two thirds were eaten by the reproductive workers even though these made up only a small proportion, 8%, of the work force. This means that policing workers obtained both direct fitness benefits as well as indirect (inclusive) fitness. In addition, we show that worker policing was carried out by a limited, specialised set of workers that was estimated to constitute approximately one quarter of the whole colony and of which 66% were non-reproductive.     

Study of soil-plant transfer of 226Ra under greenhouse conditions

A soil-plant transfer study was performed using soil from a former uranium ore processing factory in South Bohemia. We present the results from greenhouse experiments which include estimates of the time required for phytoremediation. The accumulation of ²²⁶Ra by different plant species from a mixture of garden soil and contaminated substrate was extremely variable, ranging from 0.03 to 2.20 Bq ²²⁶Ra/g DW. We found differences in accumulation of ²²⁶Ra between plants from the same genus and between cultivars of the same plant species. The results of ²²⁶Ra accumulation showed a linear relation between concentration of ²²⁶Ra in plants and concentration of ²²⁶Ra in soil mixtures. On the basis of these results we estimated the time required for phytoremediation, but this appears to be too long for practical purposes.     

Fish from industrially polluted freshwater as the main source of organochlorinated pollutants and increased frequency of thyroid disorders and dysglycemia

In a certain area of Michalovce district in East Slovakia, heavy industrial pollution by polychlorinated biphenyls (PCBs) developed in 1955-1984 and very high PCB levels in environmental and human samples are still persisting. Recently, a total of 2045 adults from this and the surrounding background pollution area have been examined using questionnaire data, thyroid volume by ultrasound (ThV), urinary iodine and serum levels of 15 PCB congeners, hexachlorobenzene (HCB), 2,2'-2-bis(4-chlorobiphenyl)-1,1-dichloroethylene (DDE), 2,2'-bis(4-chlorophenyl)-1,1,1-trichloroethane (DDT), alpha-, beta- and gamma-hexachlorocyclohexane (HCH), thyrotropin (TSH), free thyroxine (FT4), anti-thyroperoxidase antibodies (TPOab) and fasting glucose. As based on our previous findings of strikingly high level of PCBs in fish from high pollution area (e.g. mean level of 375430 ng/g lipid) and considerably lower, but still relatively high level in background pollution area (e.g. mean PCB level of 5150 ng/g), the information on the frequency of fish meals and approximate annual consumption of fish from local waters was obtained by questionnaires. The association of contaminated fish consumption with very high blood levels of PCBs, DDE and HCB and increased ThV as well as with increased frequency of positive TPOab, high values of FT4 and impaired fasting glucose (IFG) was found. These associations were also confirmed in 16 marital pairs from high pollution area with very high PCB level in both members associated with high fish consumption. It was concluded that, due to persistent heavy pollution of waters, soil and food chain namely by PCBs, but also by pesticides (e.g. DDE and HCB) resulting from their previous extensive use in agriculture, the fish from local waters still remains the most important source of these toxic pollutants which results in considerable adverse health effects.     

Distribution and movement of nutrients and metals in a Pinus radiata forest soil following applications of biosolids

Samples of biosolids, spiked with increasing amounts of Cu, Ni or Zn were applied to field plots in a Pinus radiata forest, and the nutrient and metal status of the forest litter and underlying mineral soil was monitored over a period of six years following application. The macronutrient status of the forest litter was changed markedly by the biosolids application, with substantial increases in N, P and Ca concentrations, and decreases in Mg and K. The C/N ratio of the litter was also decreased and pH was increased by the biosolids application. The metals applied with the biosolids were retained predominantly in the litter layer, and even with non-metal-spiked biosolids there were substantial increases in litter metal concentrations. There was also firm evidence of some movement of Cu, Ni and Zn into the underlying mineral soil. The potential environmental issues resulting from these changes in nutrient and metal status are discussed.     

Ethnobotanical skills and clearance of tropical rain forest for agriculture: a case study in the lowlands of Bolivia

Indigenous peoples are often considered potential allies in the conservation of biological diversity. Here we assess whether ethnobotanical skills of indigenous people contribute to a reduction in the clearance of tropical rain forest. We measured ethnobotanical skills of male household heads and area of rain forest cleared for agriculture among 128 households of Tsimane', a native Amazonian group in Bolivia. We used multivariate regressions to estimate the relation between ethnobotanical skills and area of rain forest cleared while controlling for schooling, health status, number of plots cleared, adults in household, and village of residency. We found that when the ethnobotanical skills of the male household head were doubled, the amount of tropical rain forest cleared per household was reduced by 25%. The association was stronger when the area of old-growth forest cleared was used as the dependent variable than when the area cleared from fallow forest was used as the dependent variable. People who use the forest for subsistence might place a higher value on standing forest than people who do not use it, and thus they may be more reluctant to cut down the forest.