Population genetic structure of protected allis shad (<Emphasis Type="Italic">Alosa alosa</Emphasis>) and twaite shad (<Emphasis Type="Italic">Alosa fallax</Emphasis>)

Determining the magnitude of homing behaviour within migratory fish species is essential for their conservation and management. We tested for population genetic structuring in the anadromous alosines, Alosa alosa and A. fallax fallax, to establish fidelity of stocks to spawning grounds in the United Kingdom and Ireland. Considerable genetic differences were present among populations of both species, suggesting strong fidelity to breeding grounds and compatible with homing to natal origins. Moreover, the genetic structure of A. fallax fallax showed a clear pattern of isolation-by-distance, consistent with breeding populations exchanging migrants primarily with neighbouring populations. Spatial genetic differences were on average much greater than temporal differences, indicating relatively stable genetic structure. Comparing anadromous A. fallax fallax populations to the landlocked Killarney shad subspecies, A. fallax killarnensis (Ireland), demonstrated a long history of separation. These results demonstrating regional stock structure within the British Isles will inform practical management of stocks and their spawning habitats.     

Meso-scale hydrodynamic and reproductive asynchrony affects the source–sink metapopulation structure of the coastal polychaete Pectinaria koreni

The polychaete Pectinaria koreni exhibits a complex life cycle characterized by non-overlapping generations and widespread larval dispersal. To explore how “local” metapopulation genetic structure varies spatially and temporally during population turnover, we combined observations on demography, larval dispersal through hydrodynamic modelling and population genetics of successive age cohorts in the Baie de Seine (eastern English Channel, France). Mature adults (March), newly settled (July) and later-stage juveniles (September) were sampled in 2003 on the edge and in the main demes of the metapopulation. Demes displayed an asynchronous dynamics due to variations in habitat quality affecting reproductive timing (e.g. three distinct spawning events observed) and in local larval supply linked to temporal fluctuations of hydrodynamism. Two-source populations were identified among dense areas with the greatest larval retention and self-recruitment rates: one with a single recruitment event, stable temporal genetic variation and a strong spatial genetic re-homogenization during turnover, and the other with two recruitment events and significant allele frequency changes over time. Sink habitats displayed single recruitment event and experienced strong inter-generational (juveniles vs adults) genetic changes due to genetic drift associated with strong winter mortalities. Altogether, results suggested that adult spawning asynchrony and sweepstakes reproductive success, together with genetic drift, played a greater role than hydrodynamics itself in determining effective recruitment rates at some sites and generating genetic patchiness.     

Reuse of municipal solid wastes incineration fly ashes in concrete mixtures

This study is aimed at assessing the feasibility of concrete production using stabilized m.s.w. (municipal solid waste) incineration fly ashes in addition to natural aggregates. The tested fly ashes were washed and milled, then stabilized by a cement-lime process and finally were reused as a "recycled aggregate" for cement mixture production, in substitution of a natural aggregate (with dosage of 200-400 kg m(-3)). These mixtures, after curing, were characterized with conventional physical-mechanical tests (compression, traction, flexure, modulus of elasticity, shrinkage). In samples containing 200 kg(waste) m(-3)(concrete), a good compressive strength was achieved after 28 days of curing. Furthermore, concrete leaching behavior was evaluated by means of different leaching tests, both on milled and on monolithic samples. Experimental results showed a remarkable reduction of metal leaching in comparison with raw waste. In some cases, similar behavior was observed in "natural" concrete (produced with natural aggregates) and in "waste containing" concrete.     

Effects on the structure of Arctic ecosystems in the short- and long-term perspectives

Species individualistic responses to warming and increased UV-B radiation are moderated by the responses of neighbors within communities, and trophic interactions within ecosystems. All of these responses lead to changes in ecosystem structure. Experimental manipulation of environmental factors expected to change at high latitudes showed that summer warming of tundra vegetation has generally led to smaller changes than fertilizer addition. Some of the factors manipulated have strong effects on the structure of Arctic ecosystems but the effects vary regionally, with the greatest response of plant and invertebrate communities being observed at the coldest locations. Arctic invertebrate communities are very likely to respond rapidly to warming whereas microbial biomass and nutrient stocks are more stable. Experimentally enhanced UV-B radiation altered the community composition of gram-negative bacteria and fungi, but not that of plants. Increased plant productivity due to warmer summers may dominate food-web dynamics. Trophic interactions of tundra and sub-Arctic forest plant-based food webs are centered on a few dominant animal species which often have cyclic population fluctuations that lead to extremely high peak abundances in some years. Population cycles of small rodents and insect defoliators such as the autumn moth affect the structure and diversity of tundra and forest-tundra vegetation and the viability of a number of specialist predators and parasites. Ice crusting in warmer winters is likely to reduce the accessibility of plant food to lemmings, while deep snow may protect them from snow-surface predators. In Fennoscandia, there is evidence already for a pronounced shift in small rodent community structure and dynamics that have resulted in a decline of predators that specialize in feeding on small rodents. Climate is also likely to alter the role of insect pests in the birch forest system: warmer winters may increase survival of eggs and expand the range of the insects. Insects that harass reindeer in the summer are also likely to become more widespread, abundant and active during warmer summers while refuges for reindeer/caribou on glaciers and late snow patches will probably disappear.     

Regional planning for the siting of local evaporation basins for the disposal of saline irrigation drainage: development and testing of a GIS-based suitability approach

In order to prevent salinisation of the streams of the Riverine Plain of the Murray-Darling Basin in southern Australia, evaporation basins are used to dispose of saline irrigation drainage water. Local on-farm (individual landholder) and community (shared between multiple landholders) basins are increasingly being used to prevent export of salt outside irrigation districts. There are questions regarding the availability of land suitable for these basins and their impact on the surrounding environment. We describe the use of currently available spatial data to assist in regional planning for the environmentally safe use of these basins. A GIS-based approach was developed using suitability criteria expected to minimise the risk of off-site effects of basin leakage. The criteria were proximity to surface water features, urban areas and infrastructure, water table depth and salinity, and soil hydraulic conductivity. The approach was applied to all of the major irrigation districts at 1:250,000, the scale at which data are available over the entire Riverine Plain. Confidence in well-defined parameters such as proximity to infrastructure, urban areas and surface water features was higher than for those involving interpolated point data such as water table depth, salinity, and hydraulic conductivity. Most critically, hydraulic conductivity, the most important factor for basin leakage, was found to be unreliable at this scale. Use of higher resolution data (up to 1:100,000) available for two of the irrigation districts improved confidence in both water table depth and salinity but not in hydraulic conductivity. Despite these limitations, it was found that: (i) on-farm basins can only be used on an opportunistic basis in the eastern irrigation districts, but can be widely used in the western districts; (ii) community basins can be used anywhere there is suitable land; and (iii) the results raise serious questions as to whether there is enough suitable land in the eastern districts to dispose of all of the drainage water that is produced.     

A comprehensive review of heavy metal pollution in the coastal areas of Bangladesh: abundance,bioaccumulation, health implications,and challenges

Environmental Science and Pollution Research - The coastal zone of Bangladesh, with a population density of 1278 people per square kilometer, is under serious threat due to heavy metal pollution....     

Opportunities and Challenges in Applying the 3Rs to Zoos and Aquariums

Since Russell and Burch (1959) suggested the principles of replacement, reduction, and refinement (3Rs) as a foundation for animal research, their influence has only grown in the research community. In this paper, we discuss whether the 3Rs can be constructively used as a prism to analyse decisions regarding the welfare of animals housed in zoos and aquariums (henceforth “zoo animals”). We analyse opportunities and challenges for each of the three Rs when applied to zoo animals. We discuss the following reasons to consider the use of the 3Rs in relation to zoo animals: (1) there are similarities between motivations for housing animals in zoos and using them in research that are ethically relevant to consider; (2) the professional zoo community has committed to progress towards evidence-based best practice models to ensure and enhance the welfare of animals housed in zoos; and (3) there is a growing public concern regarding the welfare of zoo animals which can, to some extent, be met by viewing current practices through the prism of the 3Rs.

     

Effects of olive mill wastewater and olive mill pomace on soil physicochemical properties and soil polyphenols

Journal of Material Cycles and Waste Management - Every year, worldwide olive oil extraction processes produce huge amounts of by-products such as (olive mill wastewater and olive mill pomace) in a...     

Valuations of Transport Nuisances and Cognitive Biases: A Survey Laboratory Experiment in the Pyrenees Region

Environmental Modeling & Assessment - We designed a survey that aims at estimating individual willingness-to-pay to reduce noise and air pollution arising from transportation activity near the...