Impact of drying and composting procedures on the concentrations of 4-nonylphenols, di-(2-ethylhexyl)phthalate and polychlorinated biphenyls in anaerobically digested sewage sludge

Enhanced treatments of sewage sludge produce a more manageable product for agricultural use by stabilizing the material, removing water, and reducing the possibility of pathogen transfer. We investigated the impact of pilot-scale composting and drying of sludge on physicochemical characteristics and on the concentrations of some organic contaminants. During the 143 day composting procedure, organic matter fell 22% and moisture by half. Concentrations of 4-nonylphenols (4-NPs) fell by 88% and di-(2-ethylhexyl) phthalate (DEHP) by 60%; losses continued throughout the procedure. Losses of total polychlorinated biphenyls (PCBs) were 11%, mostly from the lower molecular weight congeners, suggesting volatilization as the most likely loss mechanism. The drying process was much shorter, 40 days, yet organic matter content decreased by 27% and moisture by 85%. Losses of 4-NPs (39%) and DEHP (22%) were less than in composting and stopped when moisture content became constant. There were no losses of PCBs. Both treatments are simple, practical procedures that reduce the volume of waste and are applicable in situ on farms. Composting would be the method of choice for reducing organic contaminants but requires much longer times than drying.     

Estimating digestion time in gelatinous predators: a methodological comparison with the scyphomedusa Aurelia aurita

In order to quantify the trophic impact of gelatinous predators, digestion time estimates are commonly applied to counts of prey in the guts. Three primary approaches are used, the Manual-feeding, Natural-feeding and Steady-state methods; these differ in methodology and their underlying assumptions. The criteria used to define the end-point of digestion, and the resolution at which digestion progress is observed, also vary across studies. To understand the impact of such differences, we estimate digestion times of the scyphomedusa Aurelia aurita fed adult females of the copepod Acartia tonsa using these various approaches. We find ~fourfold differences which can be attributed to bias towards the slowest rates of digestion by some end-point criteria, and overestimation from low observation resolution. Artificial manipulation and the degree to which swimming and feeding behaviour are natural may also influence estimates. We provide recommendations for those quantifying digestion times of Aurelia aurita medusae and gelatinous predators.     

Perceptions of risk characteristics of earthquakes compared to other hazards and their impact on risk tolerance

People tolerate different levels of risk owing to a variety of hazards. Previous research shows that the psychometric properties of hazards predict people's tolerance of them. However, this work has not taken into account events such as earthquakes. The present study tested how earthquakes score vis‐à‐vis risk properties and risk tolerance as compared to five other familiar hazards. Participants from Wellington, New Zealand (N=139) rated these six hazards using measures of risk characteristics and risk tolerance. Participants demonstrated different levels of risk tolerance for the different hazards and viewed earthquakes as having similar risk features to nuclear power. They also preferred different risk mitigation strategies for earthquakes (more government funding) to the other five hazards (stronger legislation). In addition, earthquake risk tolerance was predicted by different risk characteristics than the other five hazards. These findings will help risk communicators in identifying which risk characteristics to target to influence citizens' risk tolerance.     

Evaluating the social and ecological effectiveness of partially protected marine areas

Marine protected areas (MPAs) are a primary tool for the stewardship, conservation, and restoration of marine ecosystems, yet 69% of global MPAs are only partially protected (i.e., are open to some form of fishing). Although fully protected areas have well-documented outcomes, including increased fish diversity and biomass, the effectiveness of partially protected areas is contested. Partially protected areas may provide benefits in some contexts and may be warranted for social reasons, yet social outcomes often depend on MPAs achieving their ecological goals to distinguish them from open areas and justify the cost of protection. We assessed the social perceptions and ecological effectiveness of 18 partially protected areas and 19 fully protected areas compared with 19 open areas along 7000 km of coast of southern Australia. We used mixed methods, gathering data via semistructured interviews, site surveys, and Reef Life (underwater visual census) surveys. We analyzed qualitative data in accordance with grounded theory and quantitative data with multivariate and univariate linear mixed-effects models. We found no social or ecological benefits for partially protected areas relative to open areas in our study. Partially protected areas had no more fish, invertebrates, or algae than open areas; were poorly understood by coastal users; were not more attractive than open areas; and were not perceived to have better marine life than open areas. These findings provide an important counterpoint to some large-scale meta-analyses that conclude partially protected areas can be ecologically effective but that draw this conclusion based on narrower measures. We argue that partially protected areas act as red herrings in marine conservation because they create an illusion of protection and consume scarce conservation resources yet provide little or no social or ecological gain over open areas. Fully protected areas, by contrast, have more fish species and biomass and are well understood, supported, and valued by the public. They are perceived to have better marine life and be improving over time in keeping with actual ecological results. Conservation outcomes can be improved by upgrading partially protected areas to higher levels of protection including conversion to fully protected areas.     

Wildlife conservation through people-centred approaches to natural resource management programmes and the control of wildlife exploitation

While the Convention on Biological Diversity (1992) introduced a new and progressive outlook on conservation, the South African government has failed to produce a comprehensive legal body of legislation to give effect to its varied obligations. Inconsistency and incompleteness of regulations governing wildlife conservation in conjunction with the failure to implement objectives to conserve wildlife through restricted exploitation with the political, social and economic motives of community conservation must be seen as major contributions to failed conservation goals. This paper analyses post-apartheid conservation laws and policies and argues that current plans for people-centred approaches to natural resource management programmes have been unsuccessful in operationalizing policy goals of biodiversity conservation and sustainable development into transparent plans for implementation. In fact, legal instruments and implementation plans seem to focus on the benefit-sharing components of community participation and therefore fail to address important issues of resource exploitation. It is suggested that where communities are expected to take part in the management of wildlife resources, the responsibility for sustainable wildlife management must be linked to the benefit-sharing instruments of the programmes. However, these would not deal with 'outsiders' like poachers and poaching driven by commercial interests. The paper proposes a model that allows communities to take control over wildlife resources.     

A conceptual model of the role of complex science in local authority consultations about air quality management

There exists a clear imperative across the EU and within the UK towards the enhanced integration of community knowledge in environmental and health decision-making processes. The underlying social force that underpins this dynamic is the drive for a more accountable, transparent and publicly acceptable decision-making arena. However, relatively little research has been undertaken on the evaluation of local air quality management consultation in particular. In this context, the paper presents an evaluation of evidence resulting from questionnaire survey and case study research undertaken in the first round of the statutory process of local air quality management (LAQM), in which local authorities are required to consult on their air quality findings and intentions. We suggest that local authority perceptions of the relative abilities of differing stakeholders' grasp of air quality science, the process that translates that science into policy, and the institutional and organizational status of stakeholders (i.e. whether they are statutory or non-statutory stakeholders) may tend to transitively determine the choice of consultation methods used, the communication strategies chosen and the relative integration of stakeholder feedback into the LAQM decision-making process. In order to interrogate this potentially problematic chain of risk communication events, a preliminary conceptual model has been developed to enable the interrogation of the pathways through, and the obstacles to, the translation of air quality knowledge. The task is to unveil the sequential chains of association that comprise the LAQM risk communication process.     

Household evacuation characteristics in American Samoa during the 2009 Samoa Islands tsunami

Tsunamis represent significant threats to human life and development in coastal communities. This quantitative study examines the influence of household characteristics on evacuation actions taken by 211 respondents in American Samoa who were at their homes during the 29 September 2009 M_w 8.1 Samoa Islands earthquake and tsunami disaster. Multiple logistic regression analysis of survey data was used to examine the association between evacuation and various household factors. Findings show that increases in distance to shoreline were associated with a slightly decreased likelihood of evacuation, whereas households reporting higher income had an increased probability of evacuation. The response in American Samoa was an effective one, with only 34 fatalities in a tsunami that reached shore in as little as 15 minutes. Consequently, future research should implement more qualitative study designs to identify event and cultural specific determinants of household evacuation behaviour to local tsunamis.     

Honest begging in the blue-footed booby: signaling food deprivation and body condition

To determine whether solicitation by blue-footed booby chicks accurately encodes their need for food, we independently manipulated the body condition and recent food ingestion of singleton chicks and recorded three measures of begging. Variations in the three measures of begging covaried only partially, but in general, chicks begged more intensely when they were in poor body condition and also when suffering recent food deprivation. Effects of body condition and recent food deprivation on begging were broadly additive, although deprived chicks in poor condition failed to beg more intensely than those in good condition. Protracted short-term deprivation may create such a high level of need that the body condition component of need becomes temporarily unimportant. Parents more frequently fed chicks that begged more intensely, chicks in poor condition, and chicks suffering food deprivation. Deprived chicks in poor condition received more food than deprived chicks in normal condition even though they did not beg more intensely, possibly because parents responded not only to current begging but also to begging earlier in the day, or to other cues to body condition. These results support the hypothesis that begging of boobies represents honest signaling of need.