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Geostatistical techniques were applied and a series of spatial indicators were calculated (occupation, aggregation, location, dispersion, spatial autocorrelation and overlap) to characterize the spatial distributions of European anchovy and sardine during summer. Two ecosystems were compared for this purpose, both located in the Mediterranean Sea: the Strait of Sicily (upwelling area) and the North Aegean Sea (continental shelf area, influenced by freshwater). Although the biomass of anchovy and sardine presented high interannual variability in both areas, the location of the centres of gravity and the main spatial patches of their populations were very similar between years. The size of the patches representing the dominant part of the abundance (80%) was mostly ecosystem- and species-specific. Occupation (area of presence) appears to be shaped by the extent of suitable habitats in each ecosystem whereas aggregation patterns (how the populations are distributed within the area of presence) were species-specific and related to levels of population biomass. In the upwelling area, both species showed consistently higher occupation values compared to the continental shelf area. Certain characteristics of the spatial distribution of sardine (e.g. spreading area, overlapping with anchovy) differed substantially between the two ecosystems. Principal component analysis of geostatistical and spatial indicators revealed that biomass was significantly related to a suite of, rather than single, spatial indicators. At the spatial scale of our study, strong correlations emerged between biomass and the first principal component axis with highly positive loadings for occupation, aggregation and patchiness, independently of species and ecosystem. Overlapping between anchovy and sardine increased with the increase of sardine biomass but decreased with the increase of anchovy. This contrasting pattern was attributed to the location of the respective major patches combined with the specific occupation patterns of the two species. The potential use of spatial indices as auxiliary stock monitoring indicators is discussed.

Fil: Marchelli, Paula. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Patagonia Norte. Estacion Experimental Agropecuaria San Carlos de Bariloche; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas; Argentina

Abstract. The instability with respect to global glaciation is a fundamental property of the climate system caused by the positive ice-albedo feedback. The atmospheric concentration of carbon dioxide (CO2) at which this Snowball bifurcation occurs changes through Earth's history, most notably because of the slowly increasing solar luminosity. Quantifying this critical CO2 concentration is not only interesting from a climate dynamics perspective but also constitutes an important prerequisite for understanding past Snowball Earth episodes, as well as the conditions for habitability on Earth and other planets. Earlier studies are limited to investigations with very simple climate models for Earth's entire history or studies of individual time slices carried out with a variety of more complex models and for different boundary conditions, making comparisons and the identification of secular changes difficult. Here, we use a coupled climate model of intermediate complexity to trace the Snowball bifurcation of an aquaplanet through Earth's history in one consistent model framework. We find that the critical CO2 concentration decreased more or less logarithmically with increasing solar luminosity until about 1 billion years ago but dropped faster in more recent times. Furthermore, there was a fundamental shift in the dynamics of the critical state about 1.2 billion years ago (unrelated to the downturn in critical CO2 values), driven by the interplay of wind-driven sea-ice dynamics and the surface energy balance: for critical states at low solar luminosities, the ice line lies in the Ferrel cell, stabilised by the poleward winds despite moderate meridional temperature gradients under strong greenhouse warming. For critical states at high solar luminosities, on the other hand, the ice line rests at the Hadley cell boundary, stabilised against the equatorward winds by steep meridional temperature gradients resulting from the increased solar energy input at lower latitudes and stronger Ekman transport in the ocean.

Honey is a natural sweet substance produced by honeybees from the nectar of flowers, plant secretions or plant-sucking insect excretions. Sugars and water constitute the major components, other minor components characterize the organoleptic and nutritional properties. To date, Salento (Apulia region, Italy) honey production is considerably threatened due to the suggested use of neonicotinoids in order to control the insect-vectored bacterium Xylella fastidiosa (subsp. pauca). Metabolomics based on Nuclear Magnetic Resonance (NMR) spectroscopy was used to describe, for the first time, the composition of honey samples from different Salento producers. Exploratory Principal Component Analysis (PCA) showed, among the observed clustering, a separation between light and dark honeys and a discrimination according to producers, both further analyzed by supervised multivariate analysis. According to the obtained data, although limited to small-scale emerging production, Salento honey shows at the molecular level, a range of specific characteristic features analogous to those exhibited by similar products originating elsewhere and appreciated by consumers. The impact on this production should therefore be carefully considered when suggesting extensive use of pesticides in the area.

An original methodology for the Water Footprint Assessment (WFA) of a Product for the wine-making industry sector is presented, with a particular focus on the evaluation procedure of the grey water. Results obtained with the proposed methodology are also presented for an Italian case study. The product was analyzed using a life-cycle approach, with the aim of studying the water volumes of each phase according to the newly-released ISO 14046 international standard. The functional unit chosen in this study is the common 0.75 liter wine bottle. An in-house software (V.I.V.A.) was implemented with the goal of accounting for all the contributions in a cradle-to-grave approach. At this stage, however, minor water volumes associated with some foreground and background processes are not assessed. The evaluation procedure was applied to a case study and green, blue, and grey water volumes were computed. Primary data were collected for a red wine produced by an Umbrian wine-making company. Results are in accordance with global average water footprint values from literature, showing a total WF of 632.2 L/bottle, with the major contribution (98.3%) given by green water, and minor contributions (1.2% and 0.5%) given by grey and blue water, respectively. A particular effort was dedicated to the definition of an improved methodology for the assessment of the virtual water volume required to dilute the load of pollutants on the environment below some reference level (Grey WF). The improved methodology was elaborated to assure the completeness of the water footprint assessment and to overcome some limitations of the reference approach. As a result, the overall WF can increase up to 3% in the most conservative hypotheses.

Local administrators and private investors rely on various urban redevelopment strategies, the choice of which depends on the economic expectations of property owners and investors. Some of these options foresee replacing obsolete buildings with new constructions; others prefer the reuse of existing assets. This study examines the conditions that make these different strategies feasible, bringing to light the aspects that favor demolition and reconstruction processes over interventions based on the redevelopment of existing assets. The analysis focuses on the variables that determine the choice between these two options. The model that has been developed highlights, on one hand, the role of urban planning tools and urban densification and, on the other, the relationship between the land market and the value of existing assets. The model has been tested on five cities in northern Italy, which fall into three territorial categories—large metropolitan cities, medium-sized cities, and cities of limited rank—to test how different social and economic contexts affect the feasibility of the strategies we evaluated. The results of the study underscore the extent to which the demolition and reconstruction of existing assets is only viable in certain limited areas and under particular market and settlement conditions. While large metropolitan areas seem to have the option of radically replacing existing real estate assets, medium-sized cities and especially small cities are constrained in redeveloping existing urban assets and must forego demolition and reconstruction projects, which do not prove to be economically feasible.