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Karstified carbonate aquifers may receive significant recharge contributions from losing streams, hence, the knowledge about surface water‐groundwater (SW‐GW) interactions is crucial with regard to water management (e.g., source protection zone delineation). The dynamics of SW‐GW interactions may depend on factors such as the relative water levels between streams and aquifers, resulting in a temporal variation of exchange, which imposes complexity to the understanding of such dynamics. This study highlights the use of high‐resolution time series and multiresolution analysis to help to gain insights into such complex dynamics. Wavelet coherence is applied on hourly time series of rainfall, stream, and spring discharges of a low‐lying karstified spring catchment to yield a correlation in the time‐frequency domain. This analysis provides comprehensive information on the overall impact of the river on the spring, which is supported by the cross‐correlation function, as well as by more detailed information, including time‐variant influences such as a threshold level of influence. Field observations of turbidity sampling at the spring appear to support this interpretation. This innovative approach relies on basic hydrological parameters, water level, or discharge, and is therefore applicable to many other systems with such existing time series., Article impact statement: Wavelet coherence yields high‐resolution information on surface water‐groundwater interaction.

The ingestion of microplastic fragments, spheres, and fibers by marine mollusks, crustaceans, and fish, including a number of commercially important species, appears to be a widespread and pervasive phenomenon. Evidence is also growing for direct impacts of microplastic ingestion on physiology, reproductive success and survival of exposed marine organisms, and transfer through food webs, although the ecological implications are not yet known. Concerns also remain over the capacity for microplastics to act as vectors for harmful chemical pollutants, including plastic additives and persistent organic pollutants, although their contribution must be evaluated alongside other known sources. The potential for humans, as top predators, to consume microplastics as contaminants in seafood is very real, and its implications for health need to be considered. An urgent need also exists to extend the geographical scope of studies of microplastic contamination in seafood species to currently underrepresented areas, and to finalize and adopt standardized methods and quality-assurance protocols for the isolation, identification, and quantification of microplastic contaminants from biological tissues. Such developments would enable more robust investigation of spatial and temporal trends, thereby contributing further evidence as a sound basis for regulatory controls. Despite the existence of considerable uncertainties and unknowns, there is already a compelling case for urgent actions to identify, control, and, where possible, eliminate key sources of both primary and secondary microplastics before they reach the marine environment. Integr Environ Assess Manag 2017;13:516-521. © 2017 SETAC.

The complexity of groundwater flooding poses unique challenges to policy makers and flood risk management agencies. An understanding of the interactions among recharge, storage and transport mechanisms during flood conditions is a precursor to effective groundwater flood risk assessment, but is often absent due to a lack of adequate data. The example of the Gort Lowlands, a major lowland karst catchment in the Republic of Ireland, is used to elucidate key flood mechanisms which must be considered when characterising groundwater flood risk in a lowland karst setting. The combination of large quantities of allogenic recharge, a high-capacity conduit system and deep surface depressions renders the catchment susceptible to groundwater flooding. Observed flood mechanisms include backwater flooding of sinks, overland flow caused by the overtopping of sink depressions, high water levels in turlough basins and surface ponding in local epikarst watersheds. Flood hazard maps are developed for the region using data collected during a major flood event in the winter of 2009, representing a significant contribution in the assessment and management of groundwater flood risk in Ireland. Major challenges to groundwater flood management and forecasting remain, however, and are discussed in the context of the prevailing hydrogeological and ecohydrological setting.

Quantifying the proportion of the river hydrograph derived from the different hydrological pathways is essential for understanding the behaviour of a catchment. This paper describes a new approach using the output from master recession curve analysis to inform a new algorithm based on the Lyne and Hollick ‘one-parameter’ signal analysis filtering algorithm. This approach was applied to six catchments (including two subcatchments of these) in Ireland. The conceptual model for each catchment consists of four main flow pathways: overland flow, interflow, shallow groundwater and deep groundwater. The results were compared with those of the master recession curve analysis, a recharge coefficient approach developed in Ireland and the semi-distributed, lumped and deterministic hydrological model Nedbor-Afstromings-Model. The new algorithm removes the ‘free variable’ aspect that is typically associated with filtering algorithms and provides a means of estimating the contribution of each pathway that is consistent with the results of hydrograph separation in catchments that are dominated by quick response pathways. These types of catchments are underlain by poorly productive aquifers that are not capable of providing large baseflows in the river. Such aquifers underlie over 73% of Ireland, ensuring that this new algorithm is applicable in the majority of catchments in Ireland and potentially in those catchments internationally that are strongly influenced by the quick-responding hydrological pathways. Copyright © 2013 John Wiley & Sons, Ltd.

Ring-necked pheasants (Phasianus colchicus) are able to store dietary calcium as medullary bone, which they may mobilize for future eggshell synthesis. We define this mechanism as calcium-loading. Previous experiments on pheasants conducted to document the importance of calcium in limiting distribution did not account for calcium-loading. We hypothesized that calcium-loading could override experimental calcium treatments of the diet. We measured egg production, egg characteristics, and femoral mineral content for pheasants that were not calcium-loaded on 7 diets differing in calcium from 0.2% to 4.5% and compared these results to a similar study on calcium-loaded pheasants. We predicted that calcium-loaded pheasants would produce more eggs than those that were not calcium-loaded. We also predicted that there would be no significant difference between femur ash fractions in non–calcium-loaded pheasants, but that the ash fraction in calcium-loaded pheasants would differ significantly between the be...

Septic tanks and other on-site systems are a common means of disposing domestic wastewater effluent in Ireland. In assessing site suitability, subsoils below the percolation trench have an important role in attenuating pollutants and hence in protecting groundwater. As part of an investigation into the hydraulic performance of treatment systems at four sites in Ireland with different subsoil characteristics, a series of samples were analysed for endocrine-disrupting chemicals (EDCs), including oestrogens, surfactants and organic oxygen compounds. EDCs were found at all four sites, but only at low concentrations (often below those at which their presence could be confirmed) and generally only in samples known to be percolating effluent. Further research should target oestrogen compounds, as these appear to be present in higher concentrations than the other EDCs and also have greater potency.

Domestic turkeys exhibit a high frequency of leg problems associated with rapid growth and heavy bird weight. We hypothesized that administering a diet high in vitamin K and flaxseed oil rich in n-3 PUFA to turkeys early in development would improve bone strength. One hundred and twenty-eight male turkeys were assigned to one of four groups in a rank-stratified design: 1) control diet containing corn oil (n-3/n-6 = 0.021) and normal vitamin K levels (menadione sodium bisulfite, 2.2 mg/kg diet); 2) high vitamin K diet containing corn oil and high vitamin K (2.2 g/kg diet); 3) flaxseed oil diet (n-3/n-6 = 0.213) containing flaxseed oil and normal levels of vitamin K and; 4) high vitamin K/flaxseed oil diet. Diets were administered 80 days. At days 17, 38, 59 and 80 eight birds from each group were sacrificed. BMC was measured using DXA and bone mineral ash. The mechanical strength of the tibiotarsus was determined using a three-point bending test. Results indicated flaxseed oil treatment significantly incre...

Broiler chickens exhibit a high frequency of leg problems, including fractures, associated with rapid growth. We hypothesized that administering a diet high in vitamin K and flaxseed oil rich in n-3 PUFA to chickens early in development would improve bone strength. Seventy-two day-old male broiler chicks were randomly assigned to one of four groups: 1) control diet (n-6/n-3=50:1) containing corn oil and normal vitamin K levels (menadione sodium bisulfite, 22.0 mg/kg diet); 2) high vitamin K diet containing corn oil and high vitamin K (3.3 g/kg diet); 3) flaxseed oil diet (n-6/n-3=5:1) containing flaxseed oil and normal levels of vitamin K and; 4) high vitamin K/flaxseed oil diet. Diets were administered six weeks. After the fourth week, six birds from each group were sacrificed each week for the next three weeks. The mechanical strength of the tibiotarsus was determined using a three-point bending test. BMC was measured using DEXA scanning and bone ashing. Results indicated no significant difference in bo...

This study investigates the effects of high dietary vitamin K and/or omega-3 levels on bone health in chickens. Hypothesis: High levels of vitamin K and omega-3 fats in the diets will increase bone mineralization and bone strength measurements in growing male Rhode Island Red chickens. Methods: Groups of five chicks were placed on one of the following diets for 4 months. 1. Control diet (vit.K = 2.2mg/kg diet, n-3/n-6 = 0.021). 2. High vitamin K diet(vit. K = 3.3g/kg diet, n-3/n-6 = 0.021). 3. High n-3/n-6 diet (vit. K = 2.2mg/kg diet, n-3/n-6 = 0.213). 4. High vitamin K-high n-3/n-6 diet (vit. K = 2.2mg/kg diet, n-3/n-6 = 0.213). Bone mineral content of the tibia was determined at months 0, 2 and 4 using dual energy x-ray absorptiometry (DEXA). Results were compared by ANOVA with Tukey-Kramer post-hoc analysis. Results: The average change in bone mineral content of the tibia was significantly higher for both the high n-3 diet and the high vitamin K-high n-3 diet (1.215 ± 0.419 g, p

Our purpose is to assess the effects of lethal alleles of engrailed on cells of the internal organs of Drosophila. Using nuclear transplantation we make mosaic flies that contain regions made by engrailed-lethal cells that are genetically labelled. We find that engrailed-lethal cells cause defects in some parts of the epidermis and central nervous system. Most of the internal organs of the fly are assessed and of those, all organs and tissues derived from the endoderm or the splanchnic and somatic mesoderm are normal; flies carrying engrailed-lethal cells in large areas of these organs are viable. We postulate that segments of the mesoderm are single units of cell lineage and that, unlike the ectoderm, they are not subdivided into anterior and posterior compartments.