Long-term changes in the frequency,intensity and duration of extreme storm surge events in southern Europe     

Alba Cid  Melisa Menéndez  Sonia Castanedo  Ana J. Abascal  Fernando J. Méndez  Raúl Medina 《Climate Dynamics》2016,46(5-6):1503-1516

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Real-time genetic spatial optimization to improve forest fire spread forecasting in high-performance computing environments     

Tomàs Artés  Andrés Cencerrado  Ana Cortés  Tomàs Margalef 《International journal of geographical information science》2016,30(3):594-611

Abstract

Forest fires are a kind of natural hazard with a high number of occurrences in southern European countries. To avoid major damages and to improve forest fire management, one can use forest fire spread simulators to predict fire behavior. When providing forest fire predictions, there are two main considerations: accuracy and computation time. In the context of natural hazards simulation, it is well known that part of the final forecast error comes from uncertainty in the input data. These data typically consist of a set of GIS files, which should be appropriately conflated. For this reason, several input data calibration methods have been developed by the scientific community. In this work, the Two-Stage calibration methodology, which has been shown to provide good results, is used. This calibration strategy is computationally intensive and time-consuming because it uses a Genetic Algorithm as a solution. Taking into account the aspect of urgency in forest fire spread prediction, it is necessary to maintain a balance between accuracy and the time needed to calibrate the input parameters. In order to take advantage of this technique, one must deal with the problem that some of the obtained solutions are impractical, since they involve simulation times that are too long, preventing the prediction system from being deployed at an operational level. A new method which finds the minimum resolution reduction for such long simulations, keeping accuracy loss to a known interval, is proposed. The proposed improvement is based on a time-aware core allocation policy that enables real-time forest fire spread forecasting. The final prediction system is a cyberinfrastructure, which enables forest fire spread prediction at real time.  相似文献   

Population structure of Merluccius merluccius along the Iberian Peninsula coast     

Castillo  Ana G.F.; Alvarez  Paula; Garcia-Vazquez  Eva 《ICES Journal of Marine Science》2005,62(8):1699-1704

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A mitochondrial DNA PCR-RFLP marker for population studies of the black scabbardfish (Aphanopus carbo)     

Quinta  Ricardo; Gomes  Laurentina; Teia dos Santos  Ana 《ICES Journal of Marine Science》2004,61(5):864-867

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Multi-level assessment of chronic toxicity of estuarine sediments with the amphipod Gammarus locusta: I. Biochemical endpoints     

Neuparth T  Correia AD  Costa FO  Lima G  Costa MH 《Marine environmental research》2005,60(1):69-91

We report on biomarker responses conducted as part of a multi-level assessment of the chronic toxicity of estuarine sediments to the amphipod Gammarus locusta. A companion article accounts for organism and population-level effects. Five moderately contaminated sediments from two Portuguese estuaries, Sado and Tagus, were assessed. Three of them were muddy and two were sandy sediments. The objective was to assess sediments that were not acutely toxic. Three of the sediments met this criterion, the other two were diluted (50% and 75%) with clean sediment until acute toxicity was absent. Following 28-d exposures, the amphipods were analysed for whole-body metal bioaccumulation, metallothionein induction (MT), DNA strand breakage (SB) and lipid peroxidation (LP). Two of the muddy sediments did not cause chronic toxicity. These findings were consistent with responses at organism and population levels that showed higher growth rates and improvement of reproductive traits for amphipods exposed to these two sediments. Two other sediments, one muddy and one sandy, exhibited pronounced chronic toxicity, affecting SB, MT induction (in muddy sediment), survival and reproduction. Potential toxicants involved in these effects were identified. The last sandy sediment exhibited some loss of DNA integrity, however growth was also enhanced. Present results, together with the organism/population-level data, and also benthic communities information, were analysed under a weight-of-evidence approach. By providing evidence of exposure (or lack of it) to contaminants in sediments, the biomarkers here applied assisted in distinguishing toxicants' impacts in test organisms from the confounding influence of other geochemical features of the sediments.  相似文献   

Isotopic evidence for the origin of an acid sulphate alteration,Styrian basin,Austria     

Ana‐Voica Bojar  Stanislaw Halas  Hans‐Peter Bojar  Janina Szaran 《地学学报》2008,20(1):45-51

The Gossendorf volcanic body is the only one in the Styrian basin that shows extensive hydrothermal alteration. K‐Ar dating of primary volcanic biotite and alteration products (alunite) suggests that the emplacement of the volcanic body and hydrothermal alteration took place synchronously, 15 Ma ago. The stable isotope compositions of the alteration products such as opal, barite, pyrite and alunite combined with crystallographia investigations indicate temperatures between 150 and 200 °C for the formation of the alteration zones. The calculated stable isotopic compositions of the parent fluid, responsible for the alteration, show an exogene marine component, which interacted with the host rock. Sulphur isotopic compositions of sulphur, sulphides and sulphates indicate disequilibrium, and progressive oxidation. This fact, combined with the mineral zonation of the alteration zone, reflects not only change in the pH but also change in the fO₂ of the ascending fluids.  相似文献   

Quantifying the impact of no-till on runoff in southern Brazil at hillslope and catchment scales     

Ana L. Londero  Jean P. G. Minella  Fabio J. A. Schneider  Dinis Deuschle  Danrlei Menezes  Olivier Evrard  Madalena Boeni  Gustavo H. Merten 《水文研究》2021,35(3):e14094

No-till (NT) is a conservation system that improves the hydrological regime of agricultural slopes by providing greater surface protection and benefits to the physical and hydrological properties of soils. However, the isolated use of NT is not enough to control runoff and its associated degradation processes. Therefore, this study aimed to evaluate the runoff of agricultural slopes under NT under different runoff control conditions by monitoring 63 rainfall events in two 2.4-ha zero-order catchments and 27 rainfall events in four 0.6-ha macroplots. The catchments are paired and similar in terms of the type of soil and relief, but different regarding the presence of terraces. The macroplots have different soil and crop management systems. By using monitoring techniques, the hyetographs and hydrographs revealed the influence of the different types of management on the catchments and macroplots and allowed rainfall characteristics, runoff volume, runoff coefficients, water infiltration, peak runoff, response times, and curve number to be analysed. The terraces positively affected the NT and controlled runoff and related variables, in addition to infiltration significantly increasing and runoff reducing in the terraced catchment. All the hydrological information assessed pointed to the positive effects provided by the presence of the terraces. The results in the macroplots showed that high amounts of phytomass and/or chiselling do not control runoff and its correlated variables in medium and high magnitude events. The study concludes by underlining the need for additional measures to control runoff (terraces), even in areas under NT and with high phytomass production. Additionally, the study emphasizes the importance of monitoring at the catchment scale to better understand the hydrological behaviour of agricultural areas and provide the necessary parameters to effectively control runoff.  相似文献   

Unravelling evapotranspiration controls and components in tropical Andean tussock grasslands     

Ana E. Ochoa-Sánchez  Patricio Crespo  Galo Carrillo-Rojas  Franklin Marín  Rolando Célleri 《水文研究》2020,34(9):2117-2127

The study of the environmental factors that control evapotranspiration and the components of evapotranspiration leads to a better understanding of the actual evapotranspiration (ET) process that links the functioning of the soil, water and atmosphere. It also improves local, regional and global ET modelling. Globally, few studies so far focussed on the controls and components of ET in alpine grasslands, especially in mountainous sites such as the tussock grasslands located in the páramo biome (above 3300 m a.s.l.). The páramo occupies 35 000 km² and provides water resources for many cities in the Andes. In this article, we unveiled the controls on ET and provided the first insights on the contribution of transpiration to ET. We found that the wet páramo is an energy-limited region and net radiation (Rn) is primarily controlling ET. ET was on average 1.7 mm/day. The monthly average evaporative fraction (ET/Rn) was 0.47 and it remained similar for wet and dry periods. The secondary controls on ET were wind speed, aerodynamic resistance and surface resistance that appeared more important for dry periods, where significantly higher ET rates were found (20% increase). During dry events, transpiration was on average 1.5 mm/day (range 0.7–2.7 mm/day), similar to other tussock grasslands in New Zealand (range 0.6–3.3 mm/day). Evidence showed interception contributes more to ET than transpiration. This study sets a precedent towards a better understanding of the evapotranspiration process and will ultimately lead to a better land-atmosphere fluxes modelling in the tropics.  相似文献   

Observed and simulated inter-decadal changes in the structure of Southern Hemisphere large-scale circulation     

Ana C. V. Freitas  Jorgen S. Frederiksen  Jennifer Whelan  Terence J. O’Kane  Tércio Ambrizzi 《Climate Dynamics》2015,45(11-12):2993-3017

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Estimation of flood risk thresholds in Mediterranean areas using rainfall indicators: case study of Valencian Region (Spain)     

Ana M. Camarasa-Belmonte  D. Butrón 《Natural Hazards》2015,78(2):1243-1266

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