A device for sampling the mud‐water interface in eutrophic lakes and bogs for residue analysis

Abstract

A tubular device has been developed making it possible to obtain layered samples of loosely aggregated, flocculent material from bogs or eutrophic lakes. The samples are up to 50 cm long and 15 cm in diameter. The sampler is free from protuberances and intact, layered samples can be taken. The tubular part of the sampler is about 85 em long, the walls of the lower 25‐cm portion harbouring a pneumatic closing mechanism which is controlled from above the water surface. An extendible handle for manipulating the sampler and for guiding it into place, is fastened to the upper end of the sampling tube. The performance and the operation of the sampler in the field are described.     

Reverse logistics in the Brazilian construction industry

In Brazil most Construction and Demolition Waste (C&D waste) is not recycled. This situation is expected to change significantly, since new federal regulations oblige municipalities to create and implement sustainable C&D waste management plans which assign an important role to recycling activities. The recycling organizational network and its flows and components are fundamental to C&D waste recycling feasibility. Organizational networks, flows and components involve reverse logistics. The aim of this work is to introduce the concepts of reverse logistics and reverse distribution channel networks and to study the Brazilian C&D waste case.     

Validation studies of turbulence closure schemes for high resolutions in mesoscale meteorological models – A case of gas dispersion at the local scale

This work is a contribution to a large project, aimed at the development of an advanced environmental assessment modelling system to be used in Japan. The modelling system here considered consisted of the RAMS and HYPACT coupled models. The RAMS code was modified to properly simulate local scale phenomena using a fine mesh size of 250 m. In this direction, the main aim here was to investigate the effect of the choice of the turbulence closure scheme on the dispersion of pollutants. Our modified version of the RAMS/HYPACT model chain was validated using field experiments which were carried out by the Japan Atomic Energy Research Institute (JAERI) in the area of Mt. Tsukuba (Japan). The mean flow, turbulence and concentration fields obtained using two alternative turbulence closure schemes are compared. A discussion on the different performances of the turbulence closures is presented and the influence of the closure schemes over the plume dispersion is investigated.     

The influence of gill and liver metabolism on the predicted bioconcentration of three pharmaceuticals in fish

The potential for xenobiotic compounds to bioconcentrate is typically expressed through the bioconcentration factor (BCF), which has gained increased regulatory significance over the past decade. Due to the expense of in vivo bioconcentration studies and the growing regulatory need to assess bioconcentration potential, BCF is often calculated via single-compartment models, using K(OW) as the primary input. Recent efforts to refine BCF models have focused on physiological factors, including the ability of the organism to eliminate the compound through metabolic transformation. This study looks at the ability of in vitro biotransformation assays using S9 fractions to provide an indication of metabolic potential. Given the importance of the fish gill and liver in metabolic transformation, the metabolic loss of ibuprofen, norethindrone and propranolol was measured using rainbow trout (Oncorhynchus mykiss) and channel catfish (Ictalurus punctatus) gill and liver S9 fractions. Metabolic transformation rates (k(M)) were calculated and integrated into a refined BCF model. A significant difference was noted between BCF solely based on K(OW) and BCF including k(M). These studies indicate that the inclusion of k(M) in BCF models can bring predicted bioconcentration estimates closer to in vivo values.     

The Inadequacy of PSD Increments to Protect Visibility in Class I Areas

This study includes an application of the first two phases of a new three-phased decision-making structure that was developed to overcome the problems related to ecological safety and social justice in site selection applications. It was conducted on a current site selection problem related to the municipal solid waste disposal facilities in Kocaeli, the most industrialized region of Turkey. In order to assess the deficiencies of the legal site selection procedures related to ecological safety, two different decision tree modes were applied separately. The first mode (“Legislation”) concerns the current buffer zone applications given in the regulations, while the second one (“Proposed”) includes the applications of the new decision-making structure proposed in this study. Since it was assumed that the subjective tendencies of the decision makers on the weightings would have a significant effect on the final decision, these two modes were assessed by employing two different weighting models. The results were obtained from all of the scenarios related to selection of suitable sites with three different area requirements (15, 250, and 500 acres) for the solid wastes generated in the Kocaeli region. The results showed that the possible changes in the decision structure could cause significant differences in the final decision related to selection of the most suitable sites. The most highest and lowest differences were at the “Legislation” mode for 15 acres and 500 acres, respectively. Furthermore, the results obtained in the study showed that the possible differentiations in the criteria weightings could also cause significant differences in the suitability ranking. Therefore, to get a reliable final decision, a statistical assessment of these differentiations should be made.

Implications: The results showed that the possible changes in the decision structure could cause significant differences in the final decision related to selection of the most suitable sites. Furthermore, the results obtained in the study showed that the possible differentiations in the criteria weightings could also cause significant differences in the suitability ranking. Therefore, to get a reliable final decision, a statistical assessment of these differentiations should be made.     

Predator cues and an herbicide affect activity and emigration in an agrobiont wolf spider

Animals use chemical cues for signaling between species. However, anthropogenic chemicals might interrupt this natural chemical information flow, with potential impacts on predator-prey interactions. Our goal was to explore how Buccaneer® Plus, a common herbicide similar to Round-up® (active ingredient glyphosate), affected the interactions between intraguild predators. The wolf spider Pardosa milvina (Hentz, 1844) is numerically dominant in agricultural systems across the eastern United States, and often falls prey to or competes with the larger wolf spider, Hogna helluo (Walckenaer, 1837) and/or the carabid beetle, Scarites quadriceps (Chaudoir, 1843). We tested the effects of chemical cues from these intraguild predators and exposure to herbicide on the activity, emigration, and survival of P. milvina using a full-factorial laboratory experiment. Both predator cues and herbicide led to a decrease in movement by P. milvina. However, although H. helluo cues alone decreased movement, S. quadriceps cues only decreased movement when combined with herbicide. These results indicate that predation risk and herbicide application likely interact in complex ways to affect the movement of a major arthropod predator in agricultural systems, and thus may have complex effects on the food web.