Organochlorine pollutants in remote mountain lake waters

Hexachlorocyclohexanes (HCHs; alpha- and gamma-isomers), endosulfans (alpha- and beta-isomers and the sulfate residue), hexachlorobenzene (HCB), dichlorodiphenyltrichloroethane (DDTs), and polychlorobiphenyls (PCBs) were measured in waters from three European remote mountain lakes situated in the Alps, Pyrenees, and Caledonian mountains. Sampling encompassed both ice-free and ice-covered periods at different water column depths. High HCH concentrations were found in all lakes, those in the Alps and Pyrenees (990-2,900 pg/L) being among the highest recorded in continental waters. Endosulfans and endosulfan sulfate (120-1,150 pg/L) were the second major group of organochlorine contaminants, showing a remarkable stability upon atmospheric long-range transport. The concentrations of HCB, DDTs, and PCB (4-8, 0.6-16, and 26-110 pg/L, respectively) were low in comparison with other continental waters. Hexachlorocyclohexanes, endosulfans, and HCB were essentially found in the dissolved phase. Phase partitioning of the more hydrophobic compounds exhibited a dependence on temperature and water-suspended particles. Comparison between different sampling seasons and water depths indicated a remarkable concentration uniformity within lake, but major interlake differences. Normalization to turnover rates showed higher interlake similarity. Preferential accumulation of the less volatile compounds in the Alp lake and significant increase of baseline contributions of organochlorine compounds and residues in the Caledonian lake are also evidenced from these turnover rates.     

Land Evaluation in a Salt-Affected Irrigated District Using an Index of Productive Potential

2 semiarid irrigated area with salt-affected soils. The available soil map is at 1:100,000 scale and its mapping units are used for the land evaluation with the FAO framework. These data are then elaborated using the index value method. This procedure gives a map of land evaluation units and a table that rates the productive potential of these units for six crops: alfalfa, barley, maize, rice, sunflower, and wheat.     

Effect of Recycling on Material Properties of Glass-filled Polyethylene Terephthalate

Recycled plastics are considered low performance materials because their properties are expected to decrease drastically with recycling. The objective of this study was to characterize a 15 wt.% glass filled polyethylene terephthalate (rPET-15GF) using six recycle generations and four recycle ratios. Mechanical properties such as tensile strength, elastic modulus, and percent elongation to failure of the PET composite were determined for various recycle generations and recycle ratios. Results show that the mechanical properties of rPET-15GF decrease slightly per recycle generation. In contrast, thermal properties of rPET-15GF were not at all affected by the recycling process. This data demonstrates that recycled glass filled PET can be used effectively to fabricate components without significantly affecting their mechanical performance.     

Strategies for controlling hazards at work

This paper presents an heuristic framework for analyzing hazards (potential for loss or harm) and strategies that may be developed to control their realization. Two basic forms of intervention for hazard control (anticipation and reaction) are identified. Three broad anticipative strategies are discussed: (1) elimination of the source of the hazard, (2) containment of the risk of its realization, and (3) mitigation of likely consequences. The communication and judgmental processes involved in decisions about strategies are shown to be embedded in the organizational “political” context, in which a variety of interests backed by varying sources of power and influence are represented. The development, implementation, and monitoring of any strategies that are decided upon are then discussed, including the fact that such actions and events may not produce the intended results. Comments are also made on the need for data provided by monitoring to be evaluated and appropriate adaptations made. Finally, a brief section of the paper discusses reactive strategies.     

Seasonal rhythm in a Mediterranean coastal fish community as monitored by a cabled observatory

To adequately describe seasonal rhythms in habitat utilization by fish communities, observations are needed that occur at a relatively high frequency and over large temporal windows. For the first time, images collected from a cabled video-observatory (the western Mediterranean expandable SEAfloor OBservatory; OBSEA) were utilized to examine habitat utilization by coastal fishes. Over the course of a year, hourly digital images of the water column and an artificial reef were obtained during daylight hours. For each image, the total number of species, an estimate of the abundance of individuals, and the Shannon Diversity Index were quantified. A total of 22 fish species commonly associated with nearshore western Mediterranean habitats were identified, and significant spatial (water column vs. artificial reef), seasonal (spring, summer, autumn, and winter), and daily (morning, midday, and sunset) differences in habitat utilization occurred. Four species (Diplodus vulgaris, Diplodus cervinus, Diplodus sargus, and Scorpaena porcus) were associated with the artificial reef, while one species (Pagrus pagrus) chiefly occurred in the water column. Chromis chromis and Diplodus annularis occurred at the site more frequently in the winter and autumn, respectively, while 14 other species utilized the site more frequently in either the spring (8 spp) or summer (6 spp). In addition, Dentex dentex and Spicara maena occurred more frequently at sunset, while D. cervinus displayed a crepuscular rhythm (occurring more frequently in the morning and at sunset). Species diversity was highest in the summer and lowest in the winter. If not taken into account when planning in situ sampling, such seasonal and/or diel differences may lead to spurious estimates of population sizes and biodiversity. We suggest that cabled video-observatories offer a non-invasive and reliable technology for faunistic sampling and population assessment in coastal water of the Mediterranean and likely elsewhere.     

Transaction costs for carbon sequestration projects in the tropical forest sector

There is general consensus that carbon (C) sequestration projects in forests are a relatively low cost option for mitigating climate change, but most studies on the subject have assumed that transaction costs are negligible. The objectives of the study were to examine transaction costs for forest C sequestration projects and to determine the significance of the costs based on economic analyses. Here we examine four case studies of active C sequestration projects being implemented in tropical countries and developed for the C market. The results from the case studies were then used with a dynamic forest and land use economic model to investigate how transaction costs affect the efficiency and cost of forest C projects globally. In the case studies transaction costs ranged from 0.38 to 27 million US dollars ($0.09 to $7.71/t CO₂) or 0.3 to 270 % of anticipated income depending principally on the price of C and project size. The three largest cost categories were insurance (under the voluntary market; 41–89 % of total costs), monitoring (3–42 %) and regulatory approval (8–50 %). The global analysis indicated that most existing estimates of marginal costs of C sequestration are underestimated by up to 30 % because transaction costs were not included.