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In the present work, an experimental study on a lab-scale adsorption refrigerator, based on activated carbon/ethanol working pair is reported. An extensive testing campaign has been carried out at the CNR ITAE laboratory, with multiple aims. First, the performance has been evaluated in terms of both COP and Specific Cooling Power (SCP), under different boundary conditions, including both air conditioning and refrigeration applications. Attractive SCPs, up to 180 W/kg and 70 W/kg for air conditioning and refrigeration, respectively, were measured. Under the same conditions, COP between 0.17 and 0.08 were obtained. In addition, different management strategies, namely, heat recovery between adsorbers and re-allocation of phase durations, were evaluated to identify their influence on the system. Both strategies confirmed the possibility of increasing COP and SCP up to 40% and 25%, respectively. Moreover, a design analysis based on the experimental results has been carried out, to suggest possible improvements of the system. The obtained results demonstrated the possibility of employing a non-toxic refrigerant like ethanol reaching performance comparable with other harmful refrigerants like ammonia and methanol.

Purpose In Italy, composting olive mill waste has become a common practice, since it mitigates the environmental problems associated with spreading the waste on land. Compost can be used to prepare growth media for plant nursery cultivation as a substitute for peat, a non-renewable resource whose extraction has long raised environmental concerns. Here, we investigate two common composting procedures--open windrow and static-pile in gas-permeable bags--and compare them to evaluate their environmental impact. Methods We perform a cradle-to-grave life cycle assessment (LCA) in accordance with ISO 14040 and 14044. The LCA considers carbon storage in the soil after 100 years, fugitive greenhouse gas (GHG) emissions, and the impacts avoided by substituting for peat. We use cumulative energy demand, global warming potential (GWP), acidification potential, and eutrophication potential indicators in a contribution analysis and explore how the re-use of olive pits for energy production and reduction of commercial fertilizers improves the environmental balance. We also present a scenario analysis that indicates how parameter fluctuations affect the results. Results and discussion Our study shows that peat's impacts can be significantly reduced from 1162.3 to 96.3 kg CO2-eq/Mg for open windrow compost or 43.1 kg CO2-eq/Mg for static-pile compost in gas-permeable bags. For static-pile composting, the lack of volatile organic compound and ammonia emissions and the detection of oxygen concentrations above 12% vol. suggest fully aerobic conditions. Fugitive greenhouse gas emissions were the most important contributions to the GWP. In the contribution analysis for static-pile composting, the avoidance of compost spreading and the carbon storage effect (due to compost usage) contributed 54% of the overall impacts to GWP and between 21 and 45% to the other indicators. Conclusions This LCA study illustrates how horticulturists can improve their resource management practices by recycling olive mill waste materials. Proper management of composting unit aeration can reduce fugitive GHG emissions.

AbstractFundamental axes of variation in plant traits result from trade-offs between costs and benefits of resource-use strategies at the leaf scale. However, it is unclear whether similar trade-offs propagate to the ecosystem level. Here, we test whether trait correlation patterns predicted by three well-known leaf- and plant-level coordination theories – the leaf economics spectrum, the global spectrum of plant form and function, and the least-cost hypothesis – are also observed between community mean traits and ecosystem processes. We combined ecosystem functional properties from FLUXNET sites, vegetation properties, and community mean plant traits into three corresponding principal component analyses. We find that the leaf economics spectrum (90 sites), the global spectrum of plant form and function (89 sites), and the least-cost hypothesis (82 sites) all propagate at the ecosystem level. However, we also find evidence of additional scale-emergent properties. Evaluating the coordination of ecosystem functional properties may aid the development of more realistic global dynamic vegetation models with critical empirical data, reducing the uncertainty of climate change projections.

Assessing Biodiversity Declines Understanding human impact on biodiversity depends on sound quantitative projection. Pereira et al. (p. 1496 , published online 26 October) review quantitative scenarios that have been developed for four main areas of concern: species extinctions, species abundances and community structure, habitat loss and degradation, and shifts in the distribution of species and biomes. Declines in biodiversity are projected for the whole of the 21st century in all scenarios, but with a wide range of variation. Hoffmann et al. (p. 1503 , published online 26 October) draw on the results of five decades' worth of data collection, managed by the International Union for Conservation of Nature Species Survival Commission. A comprehensive synthesis of the conservation status of the world's vertebrates, based on an analysis of 25,780 species (approximately half of total vertebrate diversity), is presented: Approximately 20% of all vertebrate species are at risk of extinction in the wild, and 11% of threatened birds and 17% of threatened mammals have moved closer to extinction over time. Despite these trends, overall declines would have been significantly worse in the absence of conservation actions.

The Carnian Pluvial Episode was a phase of global climatic change and biotic turnover that occurred during the early Late Triassic. In marine sedimentary basins, the arrival of huge amounts of siliciclastic sediments, the establishment of anoxic conditions, and a sudden change of the carbonate factory on platforms marked the Carnian Pluvial Episode. The sedimentary changes are closely associated with abrupt biological turnover among marine and terrestrial groups as, for example, an extinction among ammonoids and conodonts in the ocean, and a turnover of the vertebrate fauna and the flora on land. Multiple negative carbon-isotope excursions were recorded during the Carnian Pluvial Episode in both organic matter and marine carbonates, suggesting repeated injection of 13C-depleted CO2 into the ocean-atmosphere system, but their temporal and causal links with the sedimentological and palaeontological changes are poorly understood. We here review the existing carbon-isotope records and present new data on the carbon-isotope composition of organic carbon in selected sections of the western Tethys realm that record the entire Carnian Pluvial Episode. New ammonoid, conodont and sporomorph biostratigraphic data were collected and coupled to an extensive review of the existing biostratigraphy to constrain the age of the sampled sections. The results provide biostratigraphically constrained composite organic carbon-isotope curves for the Carnian, which sheds light on the temporal and causal links between the main carbon-isotope perturbations, and the distinct environmental and biotic changes that mark the Carnian Pluvial Episode. The carbon-isotope records suggest that a series of carbon-cycle perturbations, possibly recording multiple phases of volcanic activity during the emplacement of the Wrangellia Large Igneous Province, disrupted Carnian environments and ecosystems repeatedly over a remarkably long time interval of about 1 million years.