Phytoplankton photosynthetic activity and growth rates in the NW Adriatic Sea

Taxonomic composition, biomass, primary production and growth rates of the phytoplankton community were studied in two stations in the NW Adriatic Sea on a seasonal basis, in areas characterized by differing hydrological and trophic conditions. The main differences between the two stations were quantitative rather than qualitative, most phytoplankton species being common to both stations. The effects of differing nutrient concentrations and plume spreading were evident. Biomass and primary production rates were significantly higher in the coastal station (S1), and the phytoplankton distribution in the water column was markedly stratified in S1 and more even in the offshore station (S3). However, chlorophyll a specific production, potential growth rate and production efficiencies were very similar in both stations, even when phosphorus concentrations were limiting. A discrepancy between potential and actual growth rate was observed: as a feature common to both stations, comparisons between potential and actual growth rates revealed that little carbon produced by phytoplankton accumulated as algal biomass; therefore, very high loss rates were estimated.     

Environmental regulation and competitive performance: new evidence from a sectoral study

Economic theory provides different perspectives on the relationship between environmental regulation and company environmental and competitive performance. A frequently analysed issue refers to the impact of environmental regulation on company performance. Using qualitative data collected within the recently completed Environmental regulation and Market forces Providing Incentives for Resource Efficiency (EMPIRE) project, we analysed the relationship between environmental regulation and company competitiveness, operating in the building and construction (B&C) sector. Empirical evidence from the correlation analysis emphasises that environmental regulation can be an important driver of competitive performance improvements in relevant segments of the European B&C sector.     

GPS and time-depth loggers reveal underwater foraging plasticity in a flying diver,the Cape Cormorant

Knowledge on how divers exploit the water column vertically in relation to water depth is crucial to our understanding of their ecology and to their subsequent conservation. However, information is still lacking for the smaller-bodied species, due mostly to size constraints of data-loggers. Here, we report the diving behaviour of a flying diving seabird, the Cape Cormorant Phalacrocorax capensis, weighing 1.0–1.4 kg. Results were obtained by simultaneously deploying small, high resolution and high sampling frequency GPS and time-depth loggers on birds breeding on islands off Western South Africa (34°S, 18°E) in 2008. In all, dive category was assigned to all dives performed by 29 birds. Pelagic dives occurred almost as frequently as benthic dives. Pelagic dives were shallow (mean: 5 m) and took place over seafloors 5–100 m deep. Benthic dives were deeper, occurring on seafloors mainly 10–30 m deep. Dive shape was linked to dive category in only 60% of dives, while the descent rate, ascent rate and bottom duration/dive duration ratio of a dive best explained its dive category. This shows that only the concomitant use of tracking and depth tags can adequately classify diving strategies in a diver like the Cape Cormorant. Diet was mainly Cape Anchovy Engraulis encrasicolis, suggesting that birds probably displayed two contrasted strategies for capturing the same prey. Flexible foraging techniques represent an important key to survival inside the highly productive but heterogeneous Benguela upwelling ecosystem.     

Regression analysis of correlated circular data based on the multivariate von Mises distribution

Environmental and Ecological Statistics - A regression model for correlated circular data is proposed by assuming that samples of angular measurements are drawn from a multivariate von Mises...     

SEDIMENT TRANSPORT AND CHANNEL MORPHOLOGY OF SMALL,FORESTED STREAMS1

This paper reviews sediment transport and channel morphology in small, forested streams in the Pacific Northwest region of North America to assess current knowledge of channel stability and morphology relevant to riparian management practices around small streams. Small channels are defined as ones in which morphology and hydraulics may be significantly influenced by individual clasts or wood materials in the channel. Such channels are headwater channels in close proximity to sediment sources, so they reflect a mix of hillslope and channel processes. Sediment inputs are derived directly from adjacent hillslopes and from the channel banks. Morphologically significant sediments move mainly as bed load, mainly at low intensity, and there is no standard method for measurement. The larger clastic and woody elements in the channel form persistent structures that trap significant volumes of sediment, reducing sediment transport in the short term and substantially increasing channel stability. The presence of such structures makes modeling of sediment flux in these channels — a potential substitute for measurement — difficult. Channel morphology is discussed, with some emphasis on wood related features. The problem of classifying small channels is reviewed, and it is recognized that useful classifications are purpose oriented. Reach scale and channel unit scale morphologies are categorized. A “disturbance cascade” is introduced to focus attention on sediment transfers through the slope channel system and to identify management practices that affect sediment dynamics and consequent channel morphology. Gaps in knowledge, errors, and uncertainties have been identified for future research.     

Definition of compostability criteria for packaging: Initiatives in Italy

The management of solid waste is changing. The traditional approach based on landfilling of mixed refuses is shifting toward a system based on the at-source sorting of waste into specific fractions. The biological treatment of the organic fraction is considered to be an appropriate form of disposal not only for the “traditional≓ feedstock such as food scraps and vegetable and garden waste, but also for biodegradable packaging, when not recyclable in other ways. Any change from a complex system to another is difficult since many factors are to be organized and optimized. Industry must develop and manufacture compostable products, municipalities must build composting plants and organize source-separated collection, and regulatory bodies must define widely acceptable criteria of compostability. In Europe, the European Union has assigned the last task to the CEN, to provide common criteria and avoid hindrance to commercial exchanges. In Italy the UNI, the national standardization organization, has produced a working document to contribute to the discussion on the European level. In this paper the UNI scheme is described. A condensed version of this paper was presented by one of the authors (F.D.I.) at the 5th annual meeting of the BEDP Society, held in Nashville, September 22–26, 1996, during a session covering International Standards for Biodegradation Testing.     

Complexing Capacity of Thermal Waters of Montecatini Terme (Italy)

Two typical waters from thermal springs of Montecatini Terme-used as therapeutical beverages-exhibit a small complexing capacity towards Cu²⁺. By differential pulse anodic stripping voltammetry the following values were found: 0.46 μmol 1^-1 and 0.10 μmol 1^-1, respectively for Regina and Rinfresco waters.

Owing to the presence of a small amount of complexed copper in the original samples, the complexing capacity has to be regarded as residual capacity. In bottled waters from the same springs no complexing capacity was detected. Values of formation constants for copper complexes are given. No residual complexing capacity for Cu²⁺ was displayed for Tamerici and Tettuccio thermal waters.     

Olive mill solid residues as heavy metal sorbent material: a preliminary study

Biosorption of heavy metals is an innovative and alternative technology to remove these pollutants from aqueous solutions using inactive and dead biomasses such as agricultural and industrial wastes, algae and bacteria. In this study olive mill solid residue was used as heavy metal adsorbent material for its wide availability as agricultural waste and also for its cellulosic matrix, rich of potential metal binding active sites. Preliminary studies concerned with the removal of different heavy metals (Hg, Pb, Cu, Zn and Cd), the effect of pre-treatments by water and n-hexane and the regeneration possibility. Olive mill solid residue resulted able to remove heavy metals from aqueous solutions with an affinity series reflecting the hydrolytic properties of the metallic ions, but also a particular affinity for copper. It can be supposed that biosorption phenomenon occur by a general ion exchange mechanism combined with a specific complexation reaction for copper ions. Water pre-treatment is sufficient to reduce COD release in the effluent according to the law limit, while n-hexane pre-treatment strongly reduces also the adsorption properties of this material. Experimental isotherms obtained under different operating conditions were fitted using a non linear regression method for the estimation of the Langmuir parameters. Moreover a simple Scatchard plot analysis was performed for a preliminary investigation of the active sites, showing the presence of two different site affinities depending on the metal concentration, according to the previous hypothesis of two kinds of uptake mechanisms for copper biosorption. Regeneration tests gave good results in terms of yield of regeneration and also concentration ratios.