Kyoto commitments: macro and micro insights on trading and the Clean Development Mechanism

The purpose of this paper is twofold. First, we raise some issues related to the expected dimension of the carbon market. This analysis is based on a survey of model results on the implementation of the Kyoto goal with and without reliance on emissions trading. In particular, we consider both the emissions and the financial implications associated with different trading scenarios. Transfers related to international GHG trading might be equivalent to a 400% increase in foreign direct investment to countries with economies in transition. A closer look at the GHG reductions expected from the developing world also suggests that global models may be overly optimistic in their assessment of the contribution of flexibility mechanisms in meeting the Kyoto emission goals. OECD countries may need to rely more on domestic policies to reduce their emissions than what has so far been projected by global models. Second, we use a simple microeconomic model to test the potential contribution of typical power generation technologies in the context of the Clean Development Mechanism. Projects that are defined as additional in terms of the environment but already profitable can bring about significant results at a relatively low price of certified emission reductions. To assume that the contribution of the CDM will come close to what is projected by global models (both for prices and quantities) is to assume that such projects could be credited under the CDM. This revised version was published online in July 2006 with corrections to the Cover Date.     

Cadmium adsorption on vermiculite, zeolite and pumice: batch experimental studies

Batch experiments were performed to evaluate the combined effects of ionic activity, pH, and contact time on the cadmium sorption in three different minerals, vermiculite, zeolite, and pumice, commonly employed as substrata in nurseries and recently considered for their potential use in remediation methods. The extent of cadmium sorption was vermiculite>zeolite>pumice, as shown by the Langmuir and Freundlich parameters, and it was highly dependent on mineral characteristics. The percentage of cadmium sorption in zeolite and vermiculite did not depend on cadmium concentration, while in pumice this percentage was positively correlated to the initial cadmium concentration. At low cadmium concentrations (30-120 microM), the metal sorbed on zeolite was mainly present in the nonexchangeable form (70%) at levels much higher than those found for vermiculite and pumice. The primary variable responsible for determination of cadmium mobility in these minerals was confirmed to be pH. The ionic concentrations of Hoagland nutrient solution were significantly modified by both pH and mineral composition, while the presence of cadmium caused no changes. With vermiculite and zeolite, the time-course of cadmium sorption was related to mineral composition to a greater extent than to cadmium concentration. While with pumice, the percentage of cadmium sorbed after 6 weeks was lower than with the other two minerals, and it was inversely correlated to the initial cadmium concentration.     

Selection of plants for optimization of vegetative filter strips treating runoff from turfgrass

Runoff from turf environments, such as golf courses, is of increasing concern due to the associated chemical contamination of lakes, reservoirs, rivers, and ground water. Pesticide runoff due to fungicides, herbicides, and insecticides used to maintain golf courses in acceptable playing condition is a particular concern. One possible approach to mitigate such contamination is through the implementation of effective vegetative filter strips (VFS) on golf courses and other recreational turf environments. The objective of the current study was to screen ten aesthetically acceptable plant species for their ability to remove four commonly-used and degradable pesticides: chlorpyrifos (CP), chlorothalonil (CT), pendimethalin (PE), and propiconazole (PR) from soil in a greenhouse setting, thus providing invaluable information as to the species composition that would be most efficacious for use in VFS surrounding turf environments. Our results revealed that blue flag iris (Iris versicolor) (76% CP, 94% CT, 48% PE, and 33% PR were lost from soil after 3 mo of plant growth), eastern gama grass (Tripsacum dactyloides) (47% CP, 95% CT, 17% PE, and 22% PR were lost from soil after 3 mo of plant growth), and big blue stem (Andropogon gerardii) (52% CP, 91% CT, 19% PE, and 30% PR were lost from soil after 3 mo of plant growth) were excellent candidates for the optimization of VFS as buffer zones abutting turf environments. Blue flag iris was most effective at removing selected pesticides from soil and had the highest aesthetic value of the plants tested.     

Nucleic Acid Amplification-Based Methods for Detection of Enteric Viruses: Definition of Controls and Interpretation of Results

The most effective methods for virus detection in food and environmental samples are those based on nucleic acid amplification. Complex methods must be applied by the analyst in order to control for false negative results of virus detection assays in those samples that may be contaminated by virus concentrations above the detection level. The verification of analytical results is a necessity and this depends on using an appropriate suite of controls to monitor the efficacy of the critical steps in the method and allow correct result interpretations to be made. We describe the suite of controls necessary for analysing food and environmental samples for the presence of enteric viruses by nucleic acid amplification-based methods. To exclude false negative and positive interpretations of results, the inclusion of this suite of controls will be essential when considering incorporating monitoring of viruses in food or environmental safety management plans.     

Landscape changes and environmental quality: the evolution of land vulnerability and potential resilience to degradation in Italy

Resilience, considered as the ability of a system to absorb and compensate pressures derived from human and natural systems, is a topic of interest in the Mediterranean region whose landscape is the joint result of social, economic and environmental factors. The present study analyses the changes in the Italian landscape over two periods (1960–1990 and 1990–2010) of the last 50 years through a composite index of environmental resilience and vulnerability to land degradation. Results indicate that the spatial distribution of this index has been considerably changed from a relatively simple geography (mainly reflecting a latitude gradient) to a more complex pattern. The level of vulnerability of southern Italian land maintained quite stable while increasing significantly in Northern and Central Italy. The (potential) resilience level decreased over time in Central and Northern Italy while growing moderately in Southern Italy. This means that important processes of environmental changes impacting landscape resilience occurred with a different spatial trend in Italy. The composite index derived from vulnerability and potential resilience estimates at the regional scale revealed crucial to map over time the increase of surface land exposed to desertification risk. Results support the adoption of measures promoting a sustainable land management in environmentally vulnerable land with low potential to resilience.     

Cadmium biosorption by cells of Spirulina platensis TISTR 8217 immobilized in alginate and silica gel

The biosorption of cadmium by immobilized Spirulina platensis on alginate gel and silica gel was studied. The maximum biosorption capacities for alginate immobilized cells and silica immobilized cells were 70.92 and 36.63 mg Cd/g biomass, respectively. Temperature did not have an influence on metal sorption, whereas an initial pH solution did. Sorption occurred in a wide pH range (pH 3-8). The highest adsorption of alginate immobilized cells was at pH 6, while silica immobilized cell adsorption was not affected at pH between 4 and 7. The immobilized cells were reused in consecutive adsorption-desorption. The results showed that immobilized cells could be repeatedly used in the sorption process up to five times.     

A trait-based approach for downscaling complexity in plankton ecosystem models

Although predator–prey cycles can be easily predicted with mathematical models it is only since recently that oscillations observed in a chemostat predator–prey (rotifer–algal) experiment offer an interesting workbench for testing model soundness. These new observations have highlighted the limitations of the conventional modelling approach in correctly reproducing some unexpected characteristics of the cycles. Simulations are improved when changes in algal community structure, resulting from natural selection operating on an assemblage of algal clones differing in competitive ability and defence against rotifer predation, is considered in multi-prey models. This approach, however, leads to extra complexity in terms of state variables and parameters. We show here that multi-prey models with one predator can be effectively approximated with a simpler (only a few differential equations) model derived in the context of adaptive dynamics and obtained with a moment-based approximation. The moment-based approximation has been already discussed in the literature but mostly in a theoretical context, therefore we focus on the strength of this approach in downscaling model complexity by relating it to the chemostat predator–prey experiment. Being based on mechanistic concepts, our modelling framework can be applied to any community of competing species for which a trade-off between competitive ability and resistance to predators can be appropriately defined. We suggest that this approach can be of great benefit for reducing complexity in biogeochemical modelling studies at the basin or global ocean scale.     

First steps in strategic environmental assessment (SEA) adoption for coastal planning in Sicily (South Italy)

The Industrial District (I.D.) of Messina was the first public authority to consider useful the application of the Strategic Environmental Assessment (SEA) procedure for the development of an Industrial Plan regarding a coastal area. At the moment the I.D. includes six areas, but the application of the SEA concerns only the area of Pace del Mela (along the north-eastern coast of Sicily), where a “District of the two Seas” will be created, based on the synergetic development between an industrialized niche (shipbuilding) and touristic development (port and hotels). The area in which this type of intervention will occur is not in use at the moment and it was not possible to collect environmental data. For this reason, in order to describe the environmental features of this territory, we took into consideration a few indicators which could be easily identified, necessary for a post evaluation which considers the Environmental Impact Assessment (EIA) of the industrial and suburban structures to be built.     

A comparative study of the electrochemical oxidation of the herbicide tebuthiuron using boron-doped diamond electrodes

The thiadiazolylurea derivative tebuthiuron (TBH) is commonly used as an herbicide even though it is highly toxic to humans. While various processes have been proposed for the removal of organic contaminants of this type from wastewater, electrochemical degradation has shown particular promise. The aim of the present study was to investigate the electrochemical degradation of TBH using anodes comprising boron-doped (5000 and 30 000 ppm) diamond (BDD) films deposited onto Ti substrates operated at current densities in the range 10-200 mA cm⁻². Both anodes removed TBH following a similar pseudo first-order reaction kinetics with k_app close to 3.2 × 10⁻² min⁻¹. The maximum mineralization efficiency obtained was 80%. High-pressure liquid chromatography with UV-VIS detection established that both anodes degraded TBH via similar intermediates. Ion chromatography revealed that increasing concentrations of nitrate ions (up to 0.9 ppm) were formed with increasing current density, while the formation of nitrite ions was observed with both anodes at current densities ?150 mA cm⁻². The BDD film prepared at the lower doping level (5000 ppm) was more efficient in degrading TBH than its more highly doped counterpart. This unexpected finding may be explained in terms of the quantity of impurities incorporated into the diamond lattice during chemical vapor deposition.