The burrowing crab Neohelice granulata as potential bioindicator of heavy metals in estuarine systems of the Atlantic coast of Argentina

This paper presents the concentrations of total copper, lead, cadmium, and zinc in hepatopancreas of the burrowing crab Neohelice granulata from the Samboromb??n Bay (La Plata River estuary) and the Mar Chiquita coastal lagoon, Argentina. The highest accumulation of lead was observed in Mar Chiquita samples, whereas copper, zinc, and cadmium concentrations were higher in those from Samboromb??n Bay. Marked temporal and geographic availability differences were observed, while sexual differences only were observed for zinc. Finally, the validity of using this species as bioindicator of heavy-metal pollution within the assessed estuarine ecosystems is discussed.     

Computer simulation of the coagulation of suspended solids — The applicability of the Müller–Smoluchowski theory

The results of studies carried out using a computer programme simulating the coagulation of suspensions containing spherical sol particles and spherical coagulant particles are reported.The influence of the degree of dispersion of the system on the coagulation reaction kinetics was investigated. The obtained results of kinetic studies were tested in the light of classical Müller–Smoluchowski equations. The influence of the physical properties of the coagulant,such as size, density and mass, on the coagulation rate was tested. It was found that within the range described in this paper, the rate of the simulated coagulation process fulfils both the kinetic equation of a first-order reaction, and the kinetic equation of a second-order reaction.Within the tested range, a significant influence of the mass and size of the coagulant on the coagulation rate was ascertained. The kinetic Müller–Smoluchowski dependence is fulfilled in a broader range of the degree of dispersion, when the coagulant particle mass and the sol particle mass are equal. When the particle mass increases with an increase in the particle radius, the coagulation rate increases faster that it would result from the Müller's dependence.     

Wave hydrodynamics around a multi-functional artificial reef at Leirosa

This paper describes an application of the Boussinesq-type COULWAVE model to study the wave hydrodynamics in the vicinity of a multi-functional artificial reef (MFAR). This reef is under investigation and consists of a supplementary protection solution for the Leirosa sand dune system located at South of Figueira da Foz, on the Portuguese West coast. Such installation near the coastline is expected to contribute to enhance the surfing conditions in the area, protect the sand dune system in the surroundings of Leirosa beach, and increase its environmental value. Numerical calculations with the COULWAVE model were performed for four test cases, considering two reef geometries (differing in the reef angle) and two incident wave conditions (storm condition and a common wave condition). Comparisons between the results obtained, in terms of wave heights and breaking line positions allow us to assess the influence of the reef on the hydrodynamics near the beach and around the reef. Moreover, the reef performance was analysed in terms of surfability and coastal protection. The surfability parameters (breaker height, Iribarren number and peel angle) were calculated for each test case using the numerical wave heights, wave directions and wave breaking positions. Comparisons of parameters allow characterizing the most appropriate configuration of the reef to improve the surfing conditions in the study area. A methodology based on numerical free surface elevations and horizontal velocity components was developed to calculate wave directions, since this is not a direct output of the COULWAVE model. Concerning coastal protection, analyses of the mean currents around the reef were used together with observations of the velocity cells near the shoreline as an indication of the sediment transport.     

Cross-sex genetic correlation does not extend to sexual size dimorphism in spiders

Males and females are often subjected to different selection pressures for homologous traits, resulting in sex-specific optima. Because organismal attributes usually share their genetic architectures, sex-specific selection may lead to intralocus sexual conflict. Evolution of sexual dimorphism may resolve this conflict, depending on the degree of cross-sex genetic correlation (r _MF) and the strength of sex-specific selection. In theory, high r _MF implies that sexes largely share the genetic base for a given trait and are consequently sexually monomorphic, while low r _MF indicates a sex-specific genetic base and sexual dimorphism. Here, we broadly test this hypothesis on three spider species with varying degrees of female-biased sexual size dimorphism, Larinioides sclopetarius (sexual dimorphism index, SDI?=?0.85), Nuctenea umbratica (SDI?=?0.60), and Zygiella x-notata (SDI?=?0.46). We assess r _MF via same-sex and opposite-sex heritability estimates. We find moderate body mass heritability but no obvious patterns in sex-specific heritability. Against the prediction, the degree of sexual size dimorphism is unrelated to the relative strength of same-sex versus opposite-sex heritability. Our results do not support the hypothesis that sexual size dimorphism is negatively associated with r _MF. We conclude that sex-specific genetic architecture may not be necessary for the evolution of a sexually dimorphic trait.     

Designing a conservation reserve network with minimal fragmentation: A linear integer programming approach

In the biological conservation literature, the optimum reserve site selection problem has often been addressed by using the prototype set covering and maximal covering formulations, assuming that representation of species is the only criterion in site selection. This approach usually results in a small but highly fragmented reserve, which is not useful for practical conservation planning. To improve the chances of species' persistence, it may be desirable to reduce habitat fragmentation. This paper presents a linear integer programming formulation to minimize spatial gaps between selected sites in a reserve network, which is applied to a data set on breeding birds. The authors express their willingness to share the database used in this study. Those readers who wish to have access to the data may contact Robert A. Briers at r.briers@napier.ac.uk.     

Untersuchungen zur Nachhaltigkeit der Sanierung von Tributylzinnkontaminiertem Hafensediment durch Landablagerung

To allow ships to pass, most harbours have to be liberated from sedimented material. These sediments often contain high concentrations of tributyltin (TBT), which is used as a biocide in antifouling paints. Thus, the problem of a disposal which is acceptable with respect to a minimum risk for humans and the environment arises. The aim of our project was to assess land deposition as an alternative in dealing with TBT-contaminated harbour sediments. Therefore, we followed the biological degradation of TBT under aerobic and anaerobic conditions at different temperatures using defined laboratory experiments, and got important information about the land deposition, performing field measurements including biomonitoring. The biological degradation of TBT is faster under aerobic conditions and with increasing temperature. The half-lives found show the dependency of the degradation rates on the temperature between 5–55°C. The degradation rate determined for water under the same conditions (just biological degradation, without photolysis) is almost 4 times higher than in sediment. The field studies showed degradation rates of a maximum of 10–15% per year in untreated sediment and 30% per year in restacked sediments. We did not observe any interference of released TBT with ground water or surrounding areas. The TBT uptake in plants was low. Based on our results a multidimensional risk evaluation was performed, concerning the TBT and its degradation products dibutyltin (DBT) and monobutylin (MBT) released from the deposition areas. The land deposition appears to be a sustainable solution for dealing with TBT-contaminated harbour sediments.     

Stereoisomeric composition of the sex pheromone of the pine sawfly <Emphasis Type="Italic">Microdiprion pallipes</Emphasis> (Hym., Diprionidae)

Summary. The basic chemical structure of the sex pheromone of the pine sawfly Microdiprion pallipes (Fallén) has earlier been identified as the propionate ester of (2S,3S,7R/S,11R/S)/(2R,3R,7R/S,11R/S)-3,7,11- trimethyl-2-tridecanol. We now report the results from further investigations on the male response to individual stereoisomers and to blends of stereoisomers, both in electroantennographic (EAG) recordings and in field trapping experiments. We also present our attempts to determine the stereochemistry of the compounds present in females of M. pallipes. By comparing gas chromatograms and mass spectra obtained from natural extracts with those from synthetic compounds it was found that the females contain one or more of the four (2S,3S,7R/S,11R/S)-3,7,11-trimethyl-2- tridecanol isomers (SS++-1). The active pheromone component is the corresponding propionate ester 2. In EAG experiments, males responded most strongly to five propionate ester samples, namely two four-isomer blends: SS++-2 and SR++-2, and three individual stereoisomers: SSSR-, SRRR- and SRSR-2. In a series of field trapping experiments it was found that males were attracted to the SR++-2 four-isomer blend and to the individual isomer SSSR-2. Based on the EAG-recordings and field responses of males and the stereoisomers found in the females, we suggest that the propionate ester of (2S,3S,7S,11R)-3,7,11-trimethyl-2- tridecanol (SSSR-2) is used as a main component of the sex pheromone in M. pallipes. Apparently the males react to other stereoisomers in addition to that or those produced by the females.     

Polychlorinated biphenyl (PCB) residues in European roe deer (Capreolus capreolus) and red deer (Cervus elaphus) from north-western Poland

The purpose of this study was to evaluate polychlorinated biphenyls (PCBs) contamination levels in roe and red deer from north-western Poland and to assess environmental pollution in this area. A quantitative analysis was conducted using a capillary gas chromatography/mass spectrometry method. The mean concentrations of ΣPCBs (sum of PCBs: 28, 52, 101, 138, 153, 180) in liver samples were 30.24±12.35 ng·g^?1 of lipid weight (l.w.) in roe deer and 60.13±14.23 ng·g^?1 l.w. in red deer, compared with 24.21±10.02 and 45.22±9.77 ng·g^?1 in the lungs of roe and red deer, respectively. PCBs 138, 153 and 180 were the dominant congeners in the liver samples of the analysed animals, whereas PCB 138 and 153 in the lungs. TEQs levels calculated for only dioxin-like PCBs were low: 0.32 and 0.29 pg WHO-PCB-TEQ·g^?1 fat in liver of red deer and roe deer, respectively. The mean PCB concentrations obtained in our study for organs of roe deer and red deer were several times lower than those reported elsewhere. These findings show that the investigated roe and red deer originated from an area with low levels of PCB contamination.     

Adoption of environmental standards in Australia: focus on ISO 14001

This study aimed to explore the adoption of environmental standards in Australia, focusing on ISO 14001. The authors used purposive sampling to select a group of ISO 14001 certified and a group of ISO 14001 non-certified companies. Data were collected through a combination of website searches and content analysis. The study found that, overall, 92.9% of the ISO 14001 certified compared to 78.4% of the ISO 14001 non-certified companies promoted their environmental commitment through various methods. In addition, 33.4% of ISO 14001 non-certified companies (compared to 19.2% of certified companies) used their environmental engagement activities as a marketing tool. Second, 80.9% of ISO 14001 certified companies' and 26.7% of the non-certified companies' reports are easy to find and are clearly stated. The study concludes that Australian companies engage in similar environmental activities irrespective of whether they are ISO 14001 certified or not. Both management and research implications of the study's findings are presented.