Colonisers of the dark: biostalactite‐associated metazoans from “lu Lampiùne” submarine cave (Apulia,Mediterranean Sea)

Metazoan/microbial bioconstructions, or biostalactites (BSTs), discovered in submarine caves of Apulia c. 20 years ago—and later found in several shallow‐water Mediterranean caves—are receiving increasing attention in the last years. Examination of a single BST from the “lu Lampiùne” cave (Apulia), at the limit between the Adriatic and the Ionian seas, has been addressed for the first time in this paper. The BST started growing at c. 6,000 years ago with a rapid accretion of large‐sized serpulids (Protula), slowing down since about 3,000–4,000 years ago with a shift in main bioconstructors, probably caused by environmental changes. The present‐day community on the outer BST surface is dominated by skeletonised epibionts, mostly small‐sized serpulids, bryozoans and foraminifers, which contribute carbonate to the BST growth, by encrusting sponges, and by a few endobionts, including boring bivalves and insinuating sponges. New data remarkably increase biodiversity known for the “lu Lampiùne” cave and the cave habitat in the region. Thirty‐five taxa (16 bryozoans, 10 serpulids, 3 brachiopods, 2 foraminifers, 2 sponges, 1 bivalve and 1 cirriped) are recorded for the first time from Apulian marine caves, highlighting the need for further research in the area. In addition, the BST‐associated community seems to differ from those of individual BSTs from other Mediterranean caves, revealing the individuality of these communities.     

Drainage network geometry versus tectonics in the Argentera Massif (French–Italian Alps)

The Argentera Massif (French–Italian Alps), with its uniform lithology, was selected to evaluate how known Plio–Pleistocene tectonics have conditioned the drainage network geometry. The drainage network was automatically derived and ordered from a 10 m-resolution DEM. On hillshade images, alignments of morphological features were identified. The Massif was subdivided into 22 domains of 50 km² within which the directions of every river channel segment and the direction of the aligned morphological features were compared and contrasted with the strike of tectonic structures measured in the field. Results suggest that the Argentera drainage system is variously controlled by recent tectonics, depending on the Massif sector taken into account. In the NW sector, the vertical uplift is less because the strain has been accommodated in an oblique direction along a lateral thrust. In the SE sector, strain in a predominantly vertical direction along a frontal thrust has resulted in a major vertical displacement. Accordingly, the NW sector is characterized by (i) a strong geometric relationship between the main tectonic structures and the directions of river channels, (ii) longitudinal main rivers bordering the Massif, and (iii) a general trellis pattern within the domains.In the SE sector, the prolonged uplift has forced an original longitudinal drainage system to develop as a transverse system. This change has occurred by means of fluvial captures that have been identified by the presence of windgaps, fluvial elbows and knickpoints. At the domain scale, intense uplift of the SE sector has prompted the drainage pattern to evolve as a dendritic type with no clear influence of structure in the channel orientations.     

Nowcasting and real-time monitoring of heavy rainfall events inducing flash-floods: an application to Phlegraean area (Central-Southern Italy)

Natural Hazards - Severe weather events cause considerable disruptions to social and economic activities. Thus, high-precision meteorological products and services should be provided in order to...     

Recruitment of flatfish species to an estuarine nursery habitat (Lima estuary, NW Iberian Peninsula)

One of the present concerns of fish biologists involves defining and identifying nursery habitats in the context of conservation and resource management strategies. Fish nursery studies usually report upon nursery occupation during the latter juvenile stages, despite the fact that recruitment to nurseries can start early in life, during the larval phase. Here we investigated the use of a temperate estuarine nursery area, the Lima estuary (NW Portugal), by initial development stages of flatfish species before and after metamorphosis, integrating the larval and juvenile phases. The Lima estuarine flatfish community comprised twelve taxa, seven of which were present as pelagic larvae, six as juveniles and three as adults. There was a general trend of increasing spring–summer abundance of both larvae and juveniles, followed by a sharp winter decrease, mainly of larval flatfishes. The Lima estuary was used by Solea senegalensis, Platichthys flesus and Solea solea as a nursery area, with direct settlement for the two first species. In contrast, indirect settlement was suggested for S. solea, with metamorphosis occurring outside the estuarine area. Estuarine recruitment of S. senegalensis varied between years, with young larvae occurring in the estuary throughout a prolonged period that lasted 6–9 months, corroborating the protracted spawning season. P. flesus, the second most abundant species, exhibited a typical spring estuarine recruitment, without inter-annual variations. Developed larvae arrived in the estuary during spring, whereas the 0-group juveniles emerged in the following summer period. The present study contributes new insight to our understanding of the economically important S. senegalensis, and highlights the importance of integrating the planktonic larval phase into traditional flatfish nursery studies.     

The influence of vertical water balance on modelling Pantanal (Brazil) spatio‐temporal inundation dynamics

The current benchmark approach for mathematical modelling of floodplain hydrologic regime consists of dynamically coupling one‐dimensional (1D) and two‐dimensional (2D) models for flow routing along the main channel and the floodplain, respectively. For large‐scale sites, floodplain inundation may spread over hundreds of square kilometres and may last for many months and even influence seasonal floods in following years. This paper aims at evaluating the effect of vertical water balance representation on modelling a large‐scale floodplain. The Pantanal wetland (140 000 km²; Brazil) is simulated using a 1D/2D coupled model approach, which also considers the representation of vertical water processes over the floodplain. Four scenarios are simulated: Baseline (the reference scenario), NoVertBal (in which the vertical water balance over floodplain is turned off) and ETp+1 and ETp?1 scenarios, characterized by artificially increasing or decreasing daily potential evapotranspiration (ETp) by 1 mm, respectively. The results showed that the effect of the vertical water processes scenarios on channel flow is directly dependent on the lateral exchange of water between the channel and floodplain in the upstream river reach. This influence is stronger when there is a gain of water from the floodplain to the channel. The inclusion of these vertical water processes into floodplain modelling was essential to represent the process of wetting and drying, this effect being more relevant for areas not directly connected to main channels, which is a characteristic of the Pantanal region. Copyright © 2013 John Wiley & Sons, Ltd.     

Mineralogical and chemical characterization of historical mortars from military fortifications in Lisbon harbour (Portugal)

Historical mortars from sixteenth to seventeenth century military forts located at the mouth of the Tagus River in Lisbon have been characterized by polarized light microscopy (PLM), thermal analysis (TG/DTA), X-ray diffractometry (XRD) and scanning electron microscopy + energy dispersive spectroscopy (SEM + EDS). The results indicate that the mortars used were all hydraulic lime-based. The presence of well-rounded lime lumps indicates a limited use of water during the lime hydration process. The detection of hydrated calcium chloroaluminate and carboaluminate compounds mostly at binder-aggregate interfaces provides evidence for the onset of pozzolanic reactions during mortar production as further confirmed by the presence of ceramic fragments in the aggregate fractions intentionally added by the fort builders to increase the hydraulic properties of the mortars. The higher mechanical strength and greater resistance to degradation processes imparted by these pozzolanic compounds could explain why, despite the extreme proximity of the investigated sites to the sea, salt weathering processes do not appear to have significantly affected the studied mortars.     

Hypothesis on a possible role of El Ni?o in the occurrence of influenza pandemics

The El Ni?o phenomenon is the Earth??s strongest climatic fluctuation on an interannual timescale and has a quasi-global impact, although originating in the tropical Pacific Ocean. A very strong El Ni?o is recognized to cause extreme dryness and wetness in different parts of the world. We show that all the eight well-documented influenza pandemics, starting from the first certain one documented in ad 1580, originated in China and in Russia, a few years after the occurrence of a very strong or after a prolonged strong/moderate El Ni?o event. At present, the next El Ni?o will probably occur at the beginning of 2013 (Mazzarella et al. Theor Appl Climatol 100:23?C27, 2010), and this forecast may suggest to be well prepared to take appropriate precautionary epidemiological measures.     

Relationship between physical and chemical soil attributes and plant species diversity in tropical mountain ecosystems from Brazil

Although the high diversity of plant species in the rupestrian fields has been primarily attributed to the existence of a set of distinct habitats, few studies support this assertion. The present study aimed to further investigate the relationship between physical and chemical attributes of soils with the diversity of plant species in this unique ecosystem. The rupestrian field is a unique vegetation formation that covers some of the southeastern Brazilian mountains in the transition of the Atlantic rain forest and the Cerrado （savanna）. Different habitats occur according to soil characteristics （e.g., presence of rocks, sand, fertility, hydrology, etc.）. These attributes ultimately influence the vegetation that is highly adapted to the harsh edaphic and climatic mountain conditions. Five distinct habitats were studied by us： rocky outcrops, peat bogs, sandy bogs, quartz gravelfields, and ＂cerrado＂ （savanna）. A floristic survey indicated that four families are found at greater frequency： Poaceae, Asteraceae, Cyperaceae, and Leguminosae. The greatest diversity of plant species was found in the rocky outcrops habitat, followed by cerrado, peat bog, quartz gravel grassland, and sandy bogs, respectively. The main difference in the floristic composition among these habitats was related to the dominant species. Trachypogon spicatus （Poaceae） was the most dominant species in the rocky outcrops, Axonopus siccus （Poaceae） in the peat bogs, Lagenocarpus rigidus （Cyperaceae） in the sandy bogs, Schizachyrium tenerum （Poaceae） in the cerrado, while Vellozia sp. 8 （Velloziaceae） dominated the vegetation in the quartz gravel grassland. This study demonstrated that physical and chemical soil properties strongly related the diversity of plant species occurring in the different habitats of rupestrian fields.     

Late‐Pleistocene Wedge Structures Along the Patagonian Coast (Argentina): Chronological Constraints and Palaeo‐Environmental Implications

This paper investigates several wedge structures formed in continental deposits covering marine sediments deposited during MIS 5 along the central Patagonian coast of Argentina. The size and surface microtexture characteristics of the infilling sediments are consistent with a depositional environment dominated by aeolian transport. Fragments of Andean volcanic rocks (glass shards) in the wedge‐fill suggest long‐distance transport via a westerly component of wind direction. The wedges are interpreted as products of deep seasonal frost action in frozen ground, which produced open cracks that filled rapidly with partially non‐local aeolian sediments. Many wedges cross cut carbonate crusts that formed under permafrost conditions in coastal Patagonia. The radiocarbon dating of carbonate crusts yielded an age of 25–27 kyr bp , while wedge‐fill sediments are OSL dated to 14 670 ± 750 yr bp . This indicates that ground wedge formation occurred during a cold event (the Antarctic Cold Reversal period) that interrupted the permafrost degradation following the Last Glacial Maximum.     

Three-dimensional hydrodynamical simulations of the large-scale structure of W50−SS433

We present 3D hydrodynamical simulations of a precessing jet propagating inside a supernova remnant (SNR) shell, particularly applied to the W50−SS433 system in a search for the origin of its peculiar elongated morphology. Several runs were carried out with different values for the mass-loss rate of the jet, the initial radius of the SNR, and the opening angle of the precession cone. We found that our models successfully reproduce the scale and morphology of W50 when the opening angle of the jets is set to 10° or if this angle linearly varies with time. For these models, more realistic runs were made considering that the remnant is expanding into an interstellar medium with an exponential density profile (as H  i observations suggest). Taking into account all these ingredients, the large-scale morphology of the W50−SS433 system, including the asymmetry between the lobes (formed by the jet–SNR interaction), is well reproduced.