Angela Baldanza

Bio: Angela Baldanza is an academic researcher from University of Perugia. The author has contributed to research in topics: Early Pleistocene & Pleistocene. The author has an hindex of 12, co-authored 39 publications receiving 391 citations.

The plant record of the dunarobba and pietrafitta sites in the plio-pleistocene palaeoenvironmental context of central italy

Abstract: Dunarobba and Pietrafitta are two outstanding fossil sites, which provide us with a glimpse on central Italian palaeoenvironments during two different time spans. The still poorly dated Dunarobba succession is framed, mainly on the basis of continental mollusc biochronology, within the Piacenzian-Gelasian interval, whereas the Pietrafitta one is reliably dated to the Calabrian thanks to vertebrate biochronology. Here we add several new palaeobotanical data for the two sites and we provide for the first time an overview of the stratigraphic, sedimentological, palaeontological and palaeoenvironmental results so-far obtained. We also review the palaeobotanical evidence concerning the neighbouring sites of Cava Toppetti I/II, Fosso Bianco, Torre Picchio and Villa San Faustino. On the basis of the available datasets we conclude that the Dunarobba Fossil Forest, with several large conifer trunks in upright position, was produced by an ancient swamp vegetation dominated by Glyptostrobus europaeus, and including few other woody (Alnus, Cephalanthus, Cornus) and herbaceous (Carex, Cladium, Schoenoplectus) plants. Rich water-transported fruit and seed assemblages and pollen data indicate that the well-drained palaeoenvironments around the Dunarobba palaeo-swamp were covered by a forest having a floristic affinity to the modern Mixed Mesophytic Forests of East Asia, as proved by the occurrence of Cryptomeria, Eurya, Sinomenium, etc. The disappearance of the Glyptostrobus swamp forest was due to the establishment of well-drained palaeoenvironmental conditions, testified by a

The decapod community from the Early Pliocene (Zanclean) of “La Serra” quarry (San Miniato, Pisa, Toscana, central Italy): sedimentology, systematics, and palaeoenvironmental implications

Abstract: We report an unusual and rich decapod crustacean assemblage from the early Pliocene (Zanclean), recently collected during the excavations of the “La Serra” quarry, located in La Serra, near San Miniato, Pisa (Toscana, central Italy). The studied specimens have been assigned, as follows: Axius sp., Callianassa chalmasii Brocchi, 1883 , and Calliaxina cf. C. punica ( de Saint Laurent and Manning, 1982 ) (infraorder Axiidea de Saint Laurent, 1979); Gebiacantha tuscia Garassino, Pasini, De Angeli and Charbonnier sp. nov. (infraorder Gebiidea de Saint Laurent, 1979); Pagurus alatus Fabricius, 1775 , and Pagurus sp. (infraorder Anomura MacLeay, 1838); Dromia neogenica Muller, 1978 , Dromia sp., Medorippe cf. M. ampla Garassino, De Angeli, Gallo and Pasini, 2004, Ilia nucleus ( Linnaeus, 1758 ), Ristoria pliocaenica (Ristori, 1891), Pisa armata ( Latreille, 1803 ), Macropodia sp., Maja squinado (Herbst, 1788), Derilambrus angulifrons ( Latreille, 1825 ), Atelecyclus undecimdentatus (Herbst, 1783), Liocarcinus sp., Thalamita italica Garassino, Pasini, De Angeli and Charbonnier sp. nov., Pilumnus cf. P. hirtellus (Linnaeus, 1761), Eriphia cocchii Ristori, 1886 , Goneplax rhomboides ( Linnaeus, 1758 ), Goneplax sacci Crema, 1895 , (infraorder Brachyura Linnaeus, 1758 ). Moreover, two specimens have been assigned to callianassideans sensu lato and 13 specimens to indeterminate axiideans. Calliaxina Ngoc-Ho, 2003 , Gebiacantha Ngoc-Ho, 1989 , Ristoria Garassino, Pasini, De Angeli and Charbonnier gen. nov., and Macropodia Leach, 1814, are reported for the first time in the fossil record and the extant Pagurus alatus, Ilia nucleus, Pisa armata, Derilambrus angulifrons, and Pilumnus cf. P. hirtellus, are reported in the fossil record from the Pliocene. Everywhere “La Serra” quarry bio-community is very important, representing one of the richest and most diversified crustacean faunas from the Pliocene reported to date in the Mediterranean basin and worldwide, increasing notably the knowledge on the decapod populations and distribution during the early Pliocene. This community is indicative of a palaeoenvironment of shallow sublittoral water, with sandy-muddy and alternate hard shell bottom, partially covered or in proximity of seagrass, similar to the extant Mediterranean Posidonia beds, mainly inhabited by fossorial and benthonic decapods.

Pattern Recognition and Machine Learning

Abstract: Probability Distributions.- Linear Models for Regression.- Linear Models for Classification.- Neural Networks.- Kernel Methods.- Sparse Kernel Machines.- Graphical Models.- Mixture Models and EM.- Approximate Inference.- Sampling Methods.- Continuous Latent Variables.- Sequential Data.- Combining Models.

Chemostratigraphy of the Jurassic System: applications, limitations and implications for palaeoceanography

Abstract: Current chemostratigraphical studies of the Jurassic System primarily involve the use of one sedimentary component (marine organic carbon), one divalent transition metal substituted in carbonate (manganese), and two isotopic tracers: strontium-isotope ratios ( 87 Sr/ 86 Sr) and carbon-isotope ratios (δ 13 C carb and δ 13 C org ) in carbonate and in organic matter. Other parameters such as Mg/Ca and Sr/Ca ratios in calcite, oxygen-isotope ratios (δ 18 O) in carbonate, sulphur-isotope ratios (δ 34 S) in carbonate-hosted sulphate, nitrogen-isotope ratios (δ 15 N org ) in organic matter, osmium-isotope ratios ( 187 Os/ 188 Os) in black shales and neodymium-isotope ratios ( 143 Nd/ 144 Nd) in various mineral phases are also useful but at present give poor resolution because the database is incomplete or compromised by various factors. Stratigraphical patterns in total organic carbon (TOC) can be of either local or regional significance, depending on the lateral extent of the former nutrient-rich and productive water mass. Divalent manganese follows a similar pattern, being concentrated, most probably as a very early diagenetic phase, only in oxygen-depleted waters that typically underlie zones of elevated organic productivity. Shifts in Mg/Ca and Sr/Ca ratios on the time scale of ammonite subzones seem largely to reflect temperature changes. Strontium-isotope ratios from pristine skeletal calcite provide a global signal; δ 13 C values from carbonates with minimal diagenetic overprint potentially do the same, although small spatial differences in palaeo-water-mass composition may have been locally significant. Oxygen-isotope determinations on carbonate rocks and fossils generally yield values that are too scattered to be stratigraphically useful, because they reflect palaeotemperature, the evaporation–precipitation balance in sea water and the impact of any diagenesis involving an aqueous phase. Nitrogen-isotope ratios in organic matter reflect the chemistry of ancient water masses as affected by nitrate utilization and denitrification, and the stratigraphical pattern of this parameter is more likely to correlate only on a regional basis. Neodymium-isotope ratios in sea water are also water mass dependent and greatly affected by regional sources and oceanic current systems. Preliminary data on sulphur-isotope ratios in carbonates and osmium-isotope ratios in organic-rich shales, both potentially offering global correlation, indicate that these tracers may be valuable, although the records at present are not sufficiently well established to allow high-resolution regional correlation. In all cases, biostratigraphically well-dated reference sections, against which the relevant geochemical data have been calibrated, are required in the first instance. To date, studies on the stratigraphical distribution of organic carbon have been principally carried out in both northern (Boreal) and southern (Tethyan) Europe; carbon-isotope stratigraphy has been undertaken primarily, but not exclusively, on bulk pelagic sediments from the Alpine–Mediterranean or Tethyan domain; and strontium-isotope stratigraphy has been undertaken largely on calcitic skeletal material (belemnites and oysters) from northern and southern Europe. In many sections, including those containing ammonites, multi-parameter chemostratigraphy can give resolution that exceeds that attainable by classic biostratigraphical means. Strontium-isotope ratios in skeletal calcite are a particularly powerful tool for illustrating changes in sedimentary rate and revealing gaps in the stratigraphical record.

Le Règne animal distribué d'après son organisation, pour servir de base à l'histoire naturelle des animaux et d'introduction à l'anatomie comparée. Les arachnides. Atlas

Abstract: Edition accompagnee de planches gravees, representant les types de tous les genres, les caracteres distinctifs des divers groupes et les modifications de structure sur lesquelles repose cette classification

The Miocene: The Future of the Past

Abstract: The Miocene epoch (23.03–5.33 Ma) was a time interval of global warmth, relative to today. Continental configurations and mountain topography transitioned towards modern conditions, and many flora and fauna evolved into the same taxa that exist today. Miocene climate was dynamic: long periods of early and late glaciation bracketed a ∼2 Myr greenhouse interval – the Miocene Climatic Optimum (MCO). Floras, faunas, ice sheets, precipitation, pCO2, and ocean and atmospheric circulation mostly (but not ubiquitously) covaried with these large changes in climate. With higher temperatures and moderately higher pCO2 (∼400–600 ppm), the MCO has been suggested as a particularly appropriate analogue for future climate scenarios, and for assessing the predictive accuracy of numerical climate models – the same models that are used to simulate future climate. Yet, Miocene conditions have proved difficult to reconcile with models. This implies either missing positive feedbacks in the models, a lack of knowledge of past climate forcings, or the need for re‐interpretation of proxies, which might mitigate the model‐data discrepancy. Our understanding of Miocene climatic, biogeochemical, and oceanic changes on broad spatial and temporal scales is still developing. New records documenting the physical, chemical, and biotic aspects of the Earth system are emerging, and together provide a more comprehensive understanding of this important time interval. Here we review the state‐of‐the‐art in Miocene climate, ocean circulation, biogeochemical cycling, ice sheet dynamics, and biotic adaptation research as inferred through proxy observations and modelling studies.