1,285 research outputs found
Evidence of tectonic control on active arc volcanism: the Panarea-Stromboli tectonic link inferred by submarine hydrothermal vents monitoring (Aeolian arc, Italy)
The combination of the latest geophysical instruments and geochemical methods applied to the arc volcanism (Aeolian islands, Italy) has given new insights on the role of active tectonics on fluids migration. A continuous monitoring of the hydrothermal system off the island of Panarea has shown contemporaneous modifications of the vented fluids and the seismic activity of the nearby Stromboli volcano. The almost contemporary start of the last volcanic crisis at Panarea and Stromboli in 2002, besides the contemporary variation of the 3He/4He ratios at both the islands and the large number of submarine crater-shaped structures at Panarea, bears testimony to interconnections between the volcanic edifices. To confirm a tectonic drive of magmatic fluids over volcanic arcs implies that episodes of volcanic unrest can be triggered by the tectonic activity increasing the volcanic risk for the whole area, and this might be the case of the Stromboli-Panarea volcanic comple
Seismogenic-influenced fluid transport on low angle faults to the mofettes of Caprese Michelangelo (Northern Apennines)
The reservoirs feeding those mofettes are trapped over-pressurized fluids, discovered
by a deep borehole in the near vicinity. Chemical and isotope data of both the venting
gases and gases from the drilled well provide indications about their origin. We discuss
a fault-valve behavior during the rupture process as responsible mechanism for a
co-seismic fluid migration along reactivated fractures zones. A migration of hypocenters
towards the surface along the fault gives further indications for a pore pressure
diffusion process. At the surface, the mofettes changed their morphological features
macroscopically due to this enhanced gas dynamic. The phenomenological observation
of post-seismic fluid expulsion 18 months after the seismic crisis suggests the
interpretation of a long-term fluid transport process forced by pressure pulse propagation.
This result was achieved by a new approach using photographical times series.
The proposed model could help to explain a complex scenario of a long-term fluid
transport from the trapped fluid reservoir through the seismogenic zone up to the gas
emission sites at Caprese Michelangelo
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A real time integrated environment for Motorola 680xx-based VME and FASTBUS modules
The Software Components Group pSOS operating system kernel and pROBE debugger have been extended to support the Fermilab PAN-DA system for a variety of Motorola 680xx-based VME and FASTBUS modules. These extensions include: a multi-tasking, reentrant implementation of Microtec C/Pascal; a serial port driver for terminal I/O and data transfer; a message reporting facility; and enhanced debugging tools. 5 refs., 1 fig
Regional action plan for the conservation of western chimpanzees (Pan troglodytes verus) 2020–2030
This is the final version. Available from IUCN via the DOI in this recordIn 2016, IUCN uplisted the western chimpanzee, Pan troglodytes verus, from “Endangered” to “Critically Endangered”, reflecting the subspecies’ increasingly dire conservation status. Of the four recognised chimpanzee subspecies, Pan troglodytes verus is under the greatest threat. The current plan presents the status and threats to P. t. verus, based on expert evaluation of the best scientific knowledge available to date. A considerable amount of new data has improved our knowledge of the distribution and status patterns of this subspecies since the first action plan was published in 2003, and an analysis of the threats to chimpanzee populations highlights the need to address these threats and their drivers. This action plan highlights how concerned stakeholders can harmonise their efforts, emphasising the critical role of regional coordination and inter- and multidisciplinary approaches in conserving the western chimpanzee. Finally, this plan also seeks to be dynamic, embedded in a monitoring and evaluation framework that will keep priorities and strategies relevant, updating objectives and information on threats as anthropogenic and ecological pressures evolve across West Africa.Arcus FoundationUnited States Fish & Wildlife Servic
Towards systematic and evidence-based conservation planning for western chimpanzees
As animal populations continue to decline, frequently driven by large‐scale land‐use change, there is a critical need for improved environmental planning. While data‐driven spatial planning is widely applied in conservation, as of yet it is rarely used for primates. The western chimpanzee (Pan troglodytes verus) declined by 80% within 24 years and was uplisted to Critically Endangered by the IUCN Red List of Threatened Species in 2016. To support conservation planning for western chimpanzees, we systematically identified geographic areas important for this taxon. We based our analysis on a previously published data set of modeled density distribution and on several scenarios that accounted for different spatial scales and conservation targets. Across all scenarios, typically less than one‐third of areas we identified as important are currently designated as high‐level protected areas (i.e., national park or IUCN category I or II). For example, in the scenario for protecting 50% of all chimpanzees remaining in West Africa (i.e., approximately 26,500 chimpanzees), an area of approximately 60,000 km2 was selected (i.e., approximately 12% of the geographic range), only 24% of which is currently designated as protected areas. The derived maps can be used to inform the geographic prioritization of conservation interventions, including protected area expansion, “no‐go‐zones” for industry and infrastructure, and conservation sites outside the protected area network. Environmental guidelines by major institutions funding infrastructure and resource extraction projects explicitly require corporations to minimize the negative impact on great apes. Therefore, our results can inform avoidance and mitigation measures during the planning phases of such projects. This study was designed to inform future stakeholder consultation processes that could ultimately integrate the conservation of western chimpanzees with national land‐use priorities. Our approach may help in promoting similar work for other primate taxa to inform systematic conservation planning in times of growing threats
Exposure of African ape sites to climate change impacts
Large gaps remain in our understanding of the vulnerability of specific animal taxa and regions to climate change, especially regarding extreme climate impact events. Here, we assess African apes, flagship and highly important umbrella species for sympatric biodiversity. We estimated past (1981–2010) and future exposure to climate change impacts across 363 sites in Africa for RCP2.6 and RCP6.0 for near term (2021–2050) and long term (2071–2099). We used fully harmonized climate data and data on extreme climate impact events from the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP). Historic data show that 171 sites had positive temperature anomalies for at least nine of the past ten years with the strongest anomalies (up to 0.56°C) estimated for eastern chimpanzees. Climate projections suggest that temperatures will increase across all sites, while precipitation changes are more heterogeneous. We estimated a future increase in heavy precipitation events for 288 sites, and an increase in the number of consecutive dry days by up to 20 days per year (maximum increase estimated for eastern gorillas). All sites will be frequently exposed to wildfires and crop failures in the future, and the latter could impact apes indirectly through increased deforestation. 84% of sites are projected to be exposed to heatwaves and 78% of sites to river floods. Tropical cyclones and droughts were only projected for individual sites in western and central Africa. We further compiled available evidence on how climate change impacts could affect apes, for example, through heat stress and dehydration, a reduction in water sources and fruit trees, and reduced physiological performance, body condition, fertility, and survival. To support necessary research on the sensitivity and adaptability of African apes to climate change impacts, and the planning and implementation of conservation measures, we provide detailed results for each ape site on the open-access platform A.P.E.S. Wiki
GIS-BASED SUITABILITY MODELLING FOR THE EUROPEAN OYSTER WITHIN THE GERMAN EXCLUSIVE ZONE OF THE NORTH SEA
Oyster reefs are ecologically important habitats that have been suffering from anthropogenic stressors and severe damages over the past century. More than 85 % of the world's oyster reefs have already been destroyed, have disappeared or their existence is under severe and immediate threat. Due to their central ecological importance for benthic and bentho-pelagic systems and processes associated with important ecosystem functions and services, the restoration of oyster reefs is a focus of marine conservation measures worldwide. In the context of marine spatial planning and complex land use conflicts, and aimed at maximising the ecological success of such restoration measures, GIS-based habitat suitability analyses for oyster reintroduction have been conducted. The aim of the present study was to model and identify suitable habitats for the European oyster within the marine protected areas of Borkum Reefground and Sylt Outer Reef in the German Bight for which the restoration of biogenic reefs, namely native oyster reefs is a designated measure. For this purpose, a multi-criteria decision analysis was designed and applied. Based on geodata of the ecological habitat preferences of the European oyster and relevant logistic factors (contraindicated uses), suitable large- scale areas were successfully identified for which a reintroduction of the formerly native species is favourable. Both suitable and unsuitable habitats could therefore successfully be identified for both nature reserves. Due to the large impact of different standardisation procedures for the suitability variables applied, corresponding results may differ quite severely. Hence four different classifications were applied on the most important factor, ground fisheries accounting for a relative weighting of ca. 30% in the derived suitability formula. The results undermine the necessity of well-grounded scientific and practical reasons to decide on a suitable classification procedure in the multicriteria analysis
Quadratic Curvature Gravity with Second Order Trace and Massive Gravity Models in Three Dimensions
The quadratic curvature lagrangians having metric field equations with second
order trace are constructed relative to an orthonormal coframe. In
dimensions, pure quadratic curvature lagrangian having second order trace
constructed contains three free parameters in the most general case. The fourth
order field equations of some of these models, in arbitrary dimensions, are
cast in a particular form using the Schouten tensor. As a consequence, the
field equations for the New massive gravity theory are related to those of the
Topologically massive gravity. In particular, the conditions under which the
latter is "square root" of the former are presented.Comment: 24 pages, to appear in GR
Haemoglobin mass and running time trial performance after recombinant human erythropoietin administration in trained men
<p>Recombinant human erythropoietin (rHuEpo) increases haemoglobin mass (Hbmass) and maximal oxygen uptake (v˙ O2 max).</p>
<p>Purpose: This study defined the time course of changes in Hbmass, v˙ O2 max as well as running time trial performance
following 4 weeks of rHuEpo administration to determine whether the laboratory observations would translate into actual
improvements in running performance in the field.</p>
<p>Methods: 19 trained men received rHuEpo injections of 50 IUNkg21 body mass every two days for 4 weeks. Hbmass was
determined weekly using the optimized carbon monoxide rebreathing method until 4 weeks after administration. v˙ O2 max
and 3,000 m time trial performance were measured pre, post administration and at the end of the study.</p>
<p>Results: Relative to baseline, running performance significantly improved by ,6% after administration (10:3061:07 min:sec
vs. 11:0861:15 min:sec, p,0.001) and remained significantly enhanced by ,3% 4 weeks after administration
(10:4661:13 min:sec, p,0.001), while v˙ O2 max was also significantly increased post administration
(60.765.8 mLNmin21Nkg21 vs. 56.066.2 mLNmin21Nkg21, p,0.001) and remained significantly increased 4 weeks after
rHuEpo (58.065.6 mLNmin21Nkg21, p = 0.021). Hbmass was significantly increased at the end of administration compared to
baseline (15.261.5 gNkg21 vs. 12.761.2 gNkg21, p,0.001). The rate of decrease in Hbmass toward baseline values post
rHuEpo was similar to that of the increase during administration (20.53 gNkg21Nwk21, 95% confidence interval (CI) (20.68,
20.38) vs. 0.54 gNkg21Nwk21, CI (0.46, 0.63)) but Hbmass was still significantly elevated 4 weeks after administration
compared to baseline (13.761.1 gNkg21, p<0.001).</p>
<p>Conclusion: Running performance was improved following 4 weeks of rHuEpo and remained elevated 4 weeks after
administration compared to baseline. These field performance effects coincided with rHuEpo-induced elevated v˙ O2 max and
Hbmass.</p>
Shallow-water gaseohydrothermal plume studies after massive eruption at Panarea, Aeolian Islands, Italy
Copyright © 2013 Elsevier. NOTICE: This is the author’s version of a work accepted for publication by Elsevier. Changes resulting from the publishing process, including peer review, editing, corrections, structural formatting and other quality control mechanisms, may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Marine Systems, 2014, Vol.131, pp. 1-9 DOI: http://dx.doi.org/10.1016/j.jmarsys.2013.10.001Marine water dynamics in the near field of a massive gas eruption near Panarea (Aeolian Islands volcanic arc, SE Tyrrhenian Sea)
is described. ADCP current-meters were deployed during the paroxysmal phase in 2002 and 2003 a few meters from the degassing
vent, recording day-long timeseries. Datasets were sorted to remove errors and select good quality ensembles over the entire water
column. Standard deviation of error velocity was considered a proxy for inhomogeneous velocity fields over beams. Time series
intervals had been selected when the basic ADCP assumptions were fulfilled and random errors minimized. Backscatter data were
also processed to identify bubbles in the water column with the aim of locating bubble-free ensembles. Reliable timeseries are
selected combining these data. Two possible scenarios have been described: firstly, a high dynamic situation with visible surface
diverging rings of waves, entrainment on the lower part of the gas column, detrainment in the upper part and a stagnation line (SL)
at mid depth where currents were close to zero and most of the gas bubbles spread laterally; secondly, a lower dynamic situation
with water entraining into the gas plume at all depths and no surface rings of diverging waves. Reasons for these different dynamics
may be ascribed to changes in gas fluxes (one order of magnitude higher in 2002). Description of SL is important to quantify its
position in the water column and timing for entrainment-detrainment, and it can be measured by ADCP and calculated from models.Italian ISMAR-CNR, La Spezia. http://www.ismar.cnr.it/organization/geographic-units/ismar-la-spezi
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