Spatial segregation of calving and nursing Risso’s dolphins (Grampus griseus) in the Azores,and its conservation implications

Calving can be a critical period for cetaceans. Areas providing security for vulnerable calves, and high food availability for lactating females can be critical habitats requiring specific conservation measures. Here, we test the hypothesis that calving and nursing habitat could be defined for Risso’s dolphins (Grampus griseus). We investigated the spatial and temporal preferences of this species around Pico Island, Azores, using data gathered from land-based surveys and dedicated at-sea observations between 2004 and 2007. We divided observed pods into three groups: (1) those with newborn and young calves, (2) those with older calves or juveniles and (3) those consisting only of adults or sub-adults. We analysed eco-geographical variables and incorporated them into a presence-only spatial distribution model to evaluate differences in habitat suitability among the groups. We identified 694 pods of Risso’s dolphins overall. On the 267 pods observed in the first and second groups, 136 calves or juveniles were identified, of which 22 were newborns. The peak of the calving season was between June and August. The pods with newborn calves were larger and closer to shore, whereas the other groups were more widely dispersed offshore. Our results support the definition of critical habitat areas for this species, but we suggest widening the geographical coverage for better mapping around the island and throughout the archipelago generally. Conservation measures can, nevertheless, be implemented immediately, in order to reduce human impacts on a vulnerable component of the Risso’s dolphin population     

Non-consumptive effects of predator presence on copepod reproduction: insights from a mesocosm experiment

Reproduction in planktonic animals depends on numerous biotic and abiotic factors. One of them is predation pressure, which can have both direct consumptive effects on population density and sex ratio, and non-consumptive effects, for example on mating and migration behaviour. In copepods, predator vulnerability depends on their sex, motility pattern and mating behaviour. Therefore, copepods can be affected at multiple stages during the mating process. We investigated the reproductive dynamics of the estuarine copepod Eurytemora affinis in the presence and absence of its predator the mysid Neomysis integer in a mesocosm experiment. We found that the proportion of ovigerous females decreased in the presence of predators. This shift was not caused by differential predation as the absolute number of females was unaffected by mysid presence. Presence of predators reduced the ratio of males to non-ovigerous females, but not by predation of males. Our combined results suggest that the shift from ovigerous to non-ovigerous females under the presence of predators was caused by either actively delayed egg production or by shedding of egg sacs. Nauplii production was initially suppressed in the predation treatment, but increased towards the end of the experiment. The proportion of fertilized females was similar in both treatments, but constantly fell behind model predictions using a random mating model. Our results highlight the importance of non-consumptive effects of predators on copepod reproduction and hence on population dynamics.     

Synthesis of silica materials containing cyclodextrin and their applications in wastewater treatment

Environmental Chemistry Letters - Cyclodextrin-functionalized silica networks are advanced adsorbents for environmental applications. Silica-based adsorbents are low-cost and robust...     

LOW FLOW SPATIAL CHARACTERISTICS IN FORESTED HEADWATER CHANNELS OF SOUTHWEST WASHINGTON1

ABSTRACT: Patterns of dry season surface flow in forested headwater channels of southwest Washington were observed during August to September 2001 and July to October 2002. In 2001, 17 channels were sampled once, and the uppermost points of continuous flow (CF) and surface water (SW) were located. In 2002, sampling was replicated three to five times at each of 21 channels. Annual and seasonal data suggested that the location of SW varied less than CF. In most channels, SW remained at or near the channel head year around. The pattern of surface flow between CF and the channel head was used to test alternative hypotheses describing dry season recession patterns: (A) surface flow consistently retreats in a downstream direction, and (B) flow comes from fixed sources along the channel, thus surface flow retreats up‐channel towards these sources. The dominant surface flow spatial pattern in streams less than 30 percent slope was increased intermittency without a clear pattern of retreat, and thus inconsistent with either hypothesis. High gradient channels (< 30 percent slope) exhibited a combination of increased intermittency, and extensive upward retreats of surface water consistent with Hypothesis B. Differences between 2001 and 2002 suggest late summer flows in small headwater basins were controlled by spring precipitation, rather than the typically greater winter precipitation.     

Decline of materials intensiveness : The US pulp and paper industry

Despite the USA's image as a throw-away society, materials consumption per real GNP is declining, and has been for several years. Materials conservation practices in industry and a shift towards a service economy are two important factors in the decline of material intensiveness. The authors document this resource trend for the paper industry and conclude that an important cause of material intensiveness decline for this industry is the concept of product maturity. Future policy options are also analysed.     

Developing environmental quality standards for various pesticides and priority pollutants for French freshwaters

The French Ministry of the Environment and Water Agencies have derived environmental quality standards following the existing French framework called SEQ-Eau, for 28 pesticides and seven priority substances listed in the Water Framework Directive. Like other existing frameworks, SEQ-Eau relies upon the use of standard toxicity test results and assessment factors. This approach made it possible to derive the desired quality standards, but due to the lack of chronic toxicity data many of the standards are only provisional. In addition, emerging issues such as endocrine disruption should be taken into account in this framework. Depending on the available data, more flexible derivation approaches, such as the statistical distribution of NOECs, are recommended for future versions of SEQ-Eau. A comparison is made using SEQ-Eau and the methodology currently being discussed in Europe to develop environmental quality standards, showing that the European approach is more conservative. Conversely, the proposed approach under the Water Framework Directive does not cover the entire range of required quality classes.     

Modelling of silica diffusion experiments with 32Si in Boom Clay

A mathematical model describing the dissolution of nuclear glass directly disposed in clay combines a first-order dissolution rate law with the diffusion of dissolved silica in clay. According to this model, the main parameters describing the long-term dissolution of the glass are etaR, the product of the diffusion accessible porosity eta and the retardation factor R, and the apparent diffusion coefficient D(app) of dissolved silica in clay. For determining the migration parameters needed for long-term predictions, four Through-Diffusion (T-D) experiments and one percolation test have been performed on undisturbed clay cores. In the Through-Diffusion experiments, the concentration decrease after injection of 32Si (radioactive labelled silica) was measured in the inlet compartment. At the end of the T-D experiments, the clay cores were cut in thin slices and the activity of labelled silica in each slice was determined. The measured activity profiles for these four clay cores are well reproducible. Since no labelled silica could be detected in the outlet compartments, the Through-Diffusion experiments are fitted by two In-Diffusion models: one model assuming linear and reversible sorption equilibrium and a second model taking into account sorption kinetics. Although the kinetic model provides better fits, due to the sufficiently long duration of the experiments, both models give approximately similar values for the fit parameters. The single percolation test leads to an apparent diffusion coefficient value about two to three times lower than those of the Through-Diffusion tests. Therefore, dissolved silica appears to be strongly retarded in Boom Clay. A retardation factor R between 100 and 300 was determined. The corresponding in situ distribution coefficient K(d) is in the range 25-75 cm(3) g(-1). The apparent diffusion coefficient of dissolved silica in Boom Clay is estimated between 2 x 10(-13) and 7 x 10(-13) m(2) s(-1). The pore diffusion coefficient is in the range from 6 x 10(-11) to 1 x 10(-10) m(2) s(-1).     

Developing Statewide Indices of Environmental, Economic, and Social Sustainability: a look at Oregon and the Oregon Benchmarks

This research develops a method to transform the Oregon Benchmarks, a set of internationally recognized quantitative indicators designed to measure a broad array of state-level trends, into indices of social, economic, and environmental sustainability. Through multiple means, an original set of 90 Oregon Benchmarks has been narrowed into a smaller set of sustainability indicators in order to gain an integrated view of statewide sustainability as well as the capacity to look at social, environmental, and economic sustainability in isolation. The three-domain sustainability indices presented here are designed both to understand the current sustainability situation and to create a useful and informative tool for state-level policy makers interested in incorporating sustainability principles into their decision making.