LAKE SHOREZONE FUNCTIONALITY INDEX (SFI) A tool for the definition of ecological quality as indicated by Directive 2000/60/CE

www.appa.provincia.tn.it/binary/pat_appa/pubblicazioni/IFP_Manual_english_ver2.1310115028.pd

LAKE SHOREZONE FUNCTIONALITY INDEX (SFI) A tool for the definition of ecological quality as indicated by Directive 2000/60/CE

www.appa.provincia.tn.it/binary/pat_appa/pubblicazioni/IFP_Manual_english_ver2.1310115028.pd

Postglacial recolonizations, watershed crossings and human translocations shape the distribution of chub lineages around the Swiss Alps

Background: Distributions of European fish species were shaped by glaciations and the geological history of river networks until human activities partially abrogated the restrictions of biogeographical regions. The nearby origins of the Rhine, Rhone, Danube and Po rivers in the Swiss Alps allow the examination of historical and human-influenced patterns in fish genetic structure over a small geographic scale. We investigated these patterns in the widespread European chub (Squalius cephalus) from the Rhone, Rhine and Danube catchments and its proposed southern sister species Italian chub (Squalius squalus) from the Po catchment. Results: A phylogenetic tree constructed from mitochondrial Cytochrome b and COI sequences was consistent with earlier work in that it showed a separation of European chub and Italian chub, which was also reflected in microsatellite allele frequencies, morphological traits and shape differences quantified by geometric morphometrics. A new finding was that the predominant mitochondrial haplotype of European chub from the Rhine and Rhone catchments was also discovered in some individuals from Swiss populations of the Italian chub, presumably as a result of human translocation. Consistent with postglacial recolonizations from multiple refugia along the major rivers, the nuclear genetic structure of the European chub largely reflected drainage structure, but it was modified by watershed crossings between Rhine and Rhone near Lake Geneva as well as between Danube and Rhine near Lake Constance. Conclusion: Our study adds new insights into the cyprinid colonization history of central Europe by showing that multiple processes shaped the distribution of different chub lineages around the Swiss Alps. Interestingly, we find evidence that cross-catchment migration has been mediated by unusual geological events such as drainage captures or watershed crossings facilitated by retreating glaciers, as well as evidence that human transport has interfered with the historical distribution of these fish (European chub haplotypes present in the Italian chub). The desirable preservation of evolutionarily distinct lineages will thus require the prevention of further translocations

Confidence swings and sovereign risk dynamics

This study investigates the time-varying determinants of Italian sovereign risk using a Markov-switching structural vector autoregression, estimated on 1990–2018 monthly data. Sign restrictions are used for identification, and allow macroeconomic fundamentals and confidence-related factors to be characterized as separate and regime-dependent drivers of risk. We show that the latter becomes relevant during a crisis regime, when a negative confidence shock triggers demand-like macroeconomic disruptions, and sharp increases in sovereign spreads. Changes in fundamentals, that is, fiscal, supply and demand shocks, are unable to directly explain episodes of sovereign risk surges. Counterfactual simulations highlight the prevailing role of regime-dependent dynamics, where confidence switches tend to characterize the historical evolution of sovereign risk premia and reversals in spreads cyclicality

Skeletal anomalies in big-scale sand smelt (Atherina boyeri, Risso 1810, Teleostei) as a complementary tool for the assessment of the ecological status of coastal lagoons

This study tested the validity of a lagoon resident species, the big-scale sand smelt Atherina boyeri as an indicator of ecological quality of coastal lagoons. The study approach was based on the use of skeletal anomalies as a metric [1], to formulate a preliminary assessment of the environmental state of four lagoons: Fogliano, Caprolace, Sabaudia, in the province of Latina (Central Italy), and Cabras in the province of Oristano (Sardinia, Italy). A total of 451 fish were analysed for skeletal anomalies frequencies and typologies, after a whole-mount staining procedure specific for ossified tissues. The results yielded a ranking of the four lagoons based on indices such as malformation charge, ratio severe anomalies/total anomalies, and rate of severely deformed fish. In Cabras the highest values for all the indices were found, in Caprolace the lowest values, while Fogliano and Sabaudia showed intermediate values. The ranking of lagoons yielded by anomalies analysis was compared with the Total Pressure Index (TPI) obtained by an assessment based on the measure of anthropogenic pressures [2], evaluated and grouped in three categories: “Morphologic and Hydrology Changes”, “Land and Resource Use” and “Water Quality”. Results indicate Sabaudia as the lagoon with the highest TPI. Fogliano and Cabras show similar, moderate, TPIs originating from intermediate values for the three categories. Caprolace showed the lowest TPI. The two approaches give results that are not completely coherent. The indicators used to quantify anthropogenic pressures aim at a comparative assessment of the ecological status of lagoons. Skeletal anomalies in sand smelt on the other hand might result from some environmental stressor whose weight is not effectively represented in TPI. This points to the possible usefulness of indices based on fish malformations as a complementary tool to evaluate the ecological status of coastal lagoons, in the perspective of an integrated approach