Leaching of Alkali from Concrete in Contact with Waterways

Concrete is usually the preferred material for construction of structures in contact with water during their service life. Early age exposure to water is beneficial for curing of concrete structures. However, the pollution of water from freshly cast concrete in contact with water has not been investigated in detail. A significant increase in the alkalinity has recently been observed in a stream in contact with freshly installed concrete culverts. High alkalinity has caused distress to fresh water fish in the stream. A preliminary laboratory study was commenced to explore the effect of leaching of alkali into water from freshly placed concrete. Freshly cast concrete specimens were exposed to fresh water, covering a range of conditions observed in the field such as volume of concrete/volume of water, age of exposure and cement content. Analysis of the results indicated that early age contact with fresh concrete can lead to an increase in the pH levels of water up to 11, similar to the levels of pH observed in pore water inside freshly cast concrete. It was noted that until an age of 4 days from casting of concrete, the age of exposure does not significantly affect the changes in the peak pH levels of water. Continuous monitoring of water in contact with concrete also indicated that the pH levels diminish with time, which is attributed to the possible reaction of calcium hydroxide with atmospheric carbon. The paper will present the experimental study, the results, analysis and outcomes as well as planning of a more comprehensive study to observe possible ways of reducing the leaching of alkali from freshly placed concrete.     

Ecosystem functioning approach applied to a large contaminated coastal site: the study case of the Mar Piccolo of Taranto (Ionian Sea)

Knowledge on ecosystem functioning can largely contribute to promote ecosystem-based management and its application. The Mar Piccolo of Taranto is a densely populated area at a high risk of environmental crisis. Here, planktonic primary production (PP) and heterotrophic prokaryotic production (HPP) were measured as proxies of functioning in three sampling sites located in two inlets at different levels of industrial contamination, during three sampling surveys (June 2013, February and April 2014). To have a better overall view and provide some insights into the benthic-pelagic coupling, we integrated PP and HPP in the water column with those in the sediments and then discussed this with the origin of the organic matter pools based on analysis of stable isotopes. Heavy metals and polychlorobiphenyls (PCBs) were also analysed in the surface (1 cm) sediment layer and related to the overall ecosystem functioning. Multidimensional scaling (MDS) analysis, based on the main data, clearly separated the second inlet from the first one, more severely impacted by anthropogenic activities. The stable isotope mixing model suggested the prevalent terrestrial/riverine origin of the particulate organic matter pools (mean 45.5 %) in all sampling periods, whereas phytoplankton contributed up to 29 % in February. Planktonic PP and HPP rates followed the same pattern over the entire study period and seemed to respond to phytoplankton dynamics confirming this community as the main driver for the C cycling in the water column. On the contrary, benthic PP rates were almost negligible while HPP rates were lower or comparable to those in the water column indicating that although the Mar Piccolo is very shallow, the water column is much more productive than the surface sediments. The sediment resuspension is likely responsible for a pulsed input of contaminants into the water column. However, their interference with the proper functioning of the pelagic ecosystem seems to be limited to the bottom layers.     

Participatory development for regional sustainability in Western Australia: an enabling state?

Regionally specific sustainability processes that account for diverse environments and populations and that integrate social, economic, political and ecological spheres are being developed in Western Australia. A coordinated commitment to sustainability principles and a participatory philosophy by the state and local governments is necessary. This requires a transformation of the public service, from a director of passive programmes and laws to a facilitator of community projects and outcomes, towards an enabling state. An international participatory paradigm provides an array of concepts and methods for local and regional communities in partnership with government and industry to achieve this. Participatory methodologies are utilised successfully around the globe to create an institutional framework that facilitates a process of dialogue, partnership, networking, learning and managing change. This paper examines the potential contribution of a participatory approach to improve the participatory capacity of regional communities and both local and state governments towards the facilitation of regional sustainability processes.     

Structure and origin of the natural halogenated monoterpene MHC-1 and its concentrations in marine mammals and fish

The halogenated natural product previously named mixed-halogenated compound 1 (MHC-1) was isolated from the red seaweed Plocamium cartilagineum harvested in Helgoland, Germany. A total of 1.9mg of pure MHC-1 was obtained from 1g air-dried seaweed. The (1)H and (13)C NMR data matched those reported for a natural monoterpene isolated from this species. Thus, the structure of MHC-1 was established to be (1R,2S,4R,5R,1'E)-2-bromo-1-bromomethyl-1,4-dichloro-5-(2'-chloroethenyl)-5-methylcyclohexane. Moreover, the isolated monoterpene proved to be identical with the compound previously detected in marine mammals and fish from different locations. In addition we examined two samples of P. cartilagineum from Ireland and from the Antarctic; however MHC-1 was only present at low levels. Not only the concentrations were lower but also the pattern of polybrominated compounds differed from MHC-1. A calibrated solution of MHC-1 was used to determine correct concentrations from samples where previously only estimates existed relative to the gas chromatography-electron capture detector (GC/ECD) response of trans-chlordane, which underrated the MHC-1 concentrations by more than factor 2. The highest MHC-1 concentration determined to date in marine mammals is 0.14mgkg(-1) blubber. Significantly higher MHC-1 concentrations were determined in farmed fish with up to 2.2mgkg(-1) lipids. The samples with high concentrations of MHC-1 have in common that they were collected in proximity of the natural habitats of P. cartilagineum.     

Apportionment of ambient primary and secondary fine particulate matter during a 2001 summer intensive study at the CMU Supersite and NETL Pittsburgh site

Gaseous and particulate pollutant concentrations associated with five samples per day collected during a July 2001 summer intensive study at the Pittsburgh Carnegie Mellon University (CMU) Supersite were used to apportion fine particulate matter (PM2.5) into primary and secondary contributions using PMF2. Input to the PMF2 analysis included the concentrations of PM2.5 nonvolatile and semivolatile organic material, elemental carbon (EC), ammonium sulfate, trace element components, gas-phase organic material, and NO(x), NO2, and O3 concentrations. A total of 10 factors were identified. These factors are associated with emissions from various sources and facilities including crustal material, gasoline combustion, diesel combustion, and three nearby sources high in trace metals. In addition, four secondary sources were identified, three of which were associated with secondary products of local emissions and were dominated by organic material and one of which was dominated by secondary ammonium sulfate transported to the CMU site from the west and southwest. The three largest contributors to PM2.5 were secondary transported material (dominated by ammonium sulfate) from the west and southwest (49%), secondary material formed during midday photochemical processes (24%), and gasoline combustion emissions (11%). The other seven sources accounted for the remaining 16% of the PM2.5. Results obtained at the CMU site were comparable to results previously reported at the National Energy Technology Laboratory (NETL), located approximately 18 km south of downtown Pittsburgh. The major contributor at both sites was material transported from the west and southwest. Some difference in nearby sources could be attributed to meteorology as evaluated by HYSPLIT model back-trajectory calculations. These findings are consistent with the majority of the secondary ammonium sulfate in the Pittsburgh area being the result of contributions from distant transport, and thus decoupled from local activity involving organic pollutants in the metropolitan area. In contrast, the major local secondary sources were dominated by organic material.     

A model of fishing vessel accident probability

Problem: Commercial fishing is one of the least safe occupations. Method: The researchers develop a fishing vessel accident probability model for fishing areas off the northeastern United States using logit regression and daily data from 1981 to 1993. Results: The results indicate that fishing vessel accident probability declined over the study period. Higher wind speed is associated with greater accident probability. Medium-size vessels have the highest accident probability, while small vessels have the lowest. Within the study region, accident probability is lower in the southwestern section than in the northeastern section. Accidents are likely to occur closer to shore than offshore. Accident probability is lowest in spring. Impact on Industry: The probability model is an important building block in development and quantitative assessment of management mechanisms related to safety in the commercial fishing industry.     

Population dynamics of natural colonies of <Emphasis Type="Italic">Aurelia</Emphasis> sp. scyphistomae in Tasmania,Australia

The aim of this study was to identify potential environmental controls of the asexual phases of reproduction by measuring the rates of asexual reproduction (budding and strobilation) and mortality in naturally occurring populations of Aurelia sp. scyphistomae at different spatial and temporal scales. The percentage cover, density of colonies of Aurelia sp. scyphistomae, and density of the population of two naturally occurring colonies of Aurelia sp. scyphistomae were examined over 2 years in southern Tasmania. Artificial substrates were also deployed to investigate colony dynamics when density dependent effects were reduced. Clear spatial and temporal differences in the population dynamics of the colonies were observed. Density dependent effects controlled budding and recruitment of new scyphistomae to the substrate when populations were dense and space limiting. In contrast, environmental controls of budding and strobilation were more apparent in a colony with significantly greater area of bare substrate and hence room for expansion. Water temperature and rainfall (as a proxy for salinity) were linked to changes in population size. Annual and seasonal differences in population dynamics were not observed in a colony limited by space but were apparent in a colony where space was not limited. When space was removed as a limiting factor by deploying artificial substrates, a seasonal environmental effect on the rate of growth of the colony was observed. These studies suggest that the growth, survival and reproduction of the sessile colonial phase of Aurelia sp. is regulated by a combination of density dependent factors and environmental conditions, which are consequently important to the formation of jellyfish blooms.     

Potential direct fitness consequences of ornament-based mate choice in a butterfly

Female mate choice has been shown to provide direct mating benefits in several animal groups. In butterflies, for which there are increasing reports of fine-scale color-based mate choice, the evolutionary benefits that accrue from such mating biases, if any, are largely unknown. We addressed this issue in the butterfly Colias eurytheme, a species in which females choose mates on the basis of iridescent ultraviolet (UV) wing ornamentation and in which males donate reproductively beneficial nuptial gifts. In the first experiment, we assessed the mass of gifts donated to 77 virgin females by males sampled directly from a field encounter site. Despite large variance in the male adult phenotype and ejaculate, no single aspect of dorsal wing coloration, including UV brightness, chroma, or hue, was related to ejaculate mass. There was, however, an interesting interaction between the effects of male body size and copula duration upon ejaculate mass, with size scaling positively with ejaculate mass among males involved in shorter copulations (those lasting <70 min) but negatively among males in longer copulations. In the second experiment, we assessed the lifetime fecundity, fertility, and longevity of 85 females mated under similar circumstances to free-flying wild males. Although several wing color parameters proved subtly informative in more sophisticated multivariable models, no model predicted more than about 20% of the variation in any single female fitness parameter. The duration of copulation, which ranged from 35 min to over 16 h and which carries putative costs for females, was, again, only very weakly predicted by male wing color parameters (i.e., R ² = 0.089). Given the overall minor predictive power of male wing coloration in general and of UV brightness in particular, our results do not strongly support the hypothesis that female C. eurytheme prefer bright UV males to obtain direct benefits or to minimize the costs associated with lengthy copulations.     

Efficient and equitable design of marine protected areas in Fiji through inclusion of stakeholder‐specific objectives in conservation planning

The efficacy of protected areas varies, partly because socioeconomic factors are not sufficiently considered in planning and management. Although integrating socioeconomic factors into systematic conservation planning is increasingly advocated, research is needed to progress from recognition of these factors to incorporating them effectively in spatial prioritization of protected areas. We evaluated 2 key aspects of incorporating socioeconomic factors into spatial prioritization: treatment of socioeconomic factors as costs or objectives and treatment of stakeholders as a single group or multiple groups. Using as a case study the design of a system of no‐take marine protected areas (MPAs) in Kubulau, Fiji, we assessed how these aspects affected the configuration of no‐take MPAs in terms of trade‐offs between biodiversity objectives, fisheries objectives, and equity in catch losses among fisher stakeholder groups. The achievement of fisheries objectives and equity tended to trade‐off concavely with increasing biodiversity objectives, indicating that it is possible to achieve low to mid‐range biodiversity objectives with relatively small losses to fisheries and equity. Importantly, the extent of trade‐offs depended on the method used to incorporate socioeconomic data and was least severe when objectives were set for each fisher stakeholder group explicitly. We found that using different methods to incorporate socioeconomic factors that require similar data and expertise can result in plans with very different impacts on local stakeholders.