Highways protection from flood hazards,a case study: New Tama road,KSA     

Fathy  Ismail  Zeleňáková  Martina  Abd-Elhamid  Hany F. 《Natural Hazards》2020,103(1):479-496

Natural Hazards - Highways in arid regions are highly exposed to damage by floods. This requires intensive analysis of flood quantity, time and direction that can be used to design the suitable...  相似文献   

Geological mapping reveals the role of Early Jurassic rift architecture in the dispersal of calciturbidites: New insights from the Central and Northern Apennines     

Angelo Cipriani  Martina Caratelli  Massimo Santantonio 《Basin Research》2020,32(6):1485-1509

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Using Clustered Heat Maps in Mineral Exploration to Visualize Volcanic-Hosted Massive Sulfide Alteration and Mineralization     

Feltrin  Leonardo  Bertelli  Martina 《Natural Resources Research》2020,29(1):311-344

Natural Resources Research - This study proposes an extension of a visualization approach common in biochemistry (the clustered heat maps—CHMs) to geochemical data with the main objective of...  相似文献   

Towards new applications of underwater photogrammetry for investigating coral reef morphology and habitat complexity in the Myeik Archipelago,Myanmar     

Martina Anelli  Tommaso Julitta  Luca Fallati  Paolo Galli  Micol Rossini  Roberto Colombo 《国际地球制图》2019,34(5):459-472

Photogrammetry represents a non-destructive, cost-effective tool for coral reef monitoring, able to integrate traditional remote sensing techniques and support researchers’ work. However, its application to submerged habitats is still in early stage. We present new ways to employ Structure from Motion techniques to infer properties of reef habitats. In particular, we propose the use of Digital Surface Models and Digital Terrain Models for assessing coral colonies extension and height and discriminating between seabed and coral cover. Such information can be coupled with digital rugosity estimates to improve habitat characterization. DTM, DSM and orthophotos were derived and used to compute a series of metrics like coral morphologies, reef topography, coral cover and structural complexity. We show the potentialities offered by underwater photogrammetry and derived products to provide useful basic information for marine habitat mapping, opening the possibility to extend these methods for large-scale assessment and monitoring of coral reefs.  相似文献   

Assessment of Water Quality in the Elbe River at Low Water Conditions Based on Factor Analysis     

Martina Baborowski  Olaf Büttner  Jürgen W. Einax 《洁净——土壤、空气、水》2011,39(5):437-443

An assessment of water quality measurements during a long‐lasting low water period in the Elbe River is presented. Weekly samples were taken from May to December 2003 at a sampling site in the middle part of the Elbe River. For multivariate data analysis, 34 parameters of 46 samplings were considered. As a result of this analysis, 78% of the variance of the data set is explained by five factors. They can be assigned to the following latent variables: season (37.5%) > tributaries (12.7%) > re‐suspension (10.4%) > discharge (9.4%) > complexation (8.5%). For the investigated sampling site, two key processes were identified as dominating factors on the water quality during low water conditions. First, seasonal phytoplankton development caused changes in redox conditions with consequences for re‐solution of pollutants from sediments. Second, tributaries have a higher impact on the main stream, due to changes in mixing processes. Therefore, in addition to flood investigations, monitoring strategies, and management plans should be developed in order to survey changes in water quality during low water conditions.  相似文献   

Leaching of metals from copper smelter flue dust (Mufulira,Zambian Copperbelt)     

Martina Vítková  Vojtěch Ettler  Jiri Hyks  Thomas Astrup  Bohdan Kříbek 《Applied Geochemistry》2011

The leaching behaviour of electrostatic precipitator dust from the Mufulira Cu smelter (Copperbelt, Zambia) was studied using a 48-h pH-static leaching experiment (CEN/TS 14997). The release of metals (Cd, Co, Cu, Ni, Pb and Zn) and changes in mineralogical composition using X-ray diffraction and PHREEQC-2 modelling were investigated in the pH range of 3–7. The highest concentrations of metals were released at pH 3–4.5, which encompasses the natural pH of the dust suspension (～4.3). About 40% of the total Cu was leached at pH 3, yielding 107 g/kg. Chalcanthite (CuSO₄·5H₂O), magnetite (Fe₃O₄) and delafossite (CuFeO₂) represented the principal phases of the studied dust. In contact with water, chalcanthite was dissolved and hydrated Cu sulphates precipitated at pH 4–7. Gypsum (CaSO₄·2H₂O) and secondary Fe or Al phases were observed in the leached residues. Serious environmental impact due to leaching may occur in dust-contaminated soil systems in the vicinity of the smelting plants.  相似文献   

Differences in the neighborhood: Structural variations in the carapace of shore crabs Carcinus maenas (Decapoda: Portunidae)     

Allan T. Souza  Martina I. Ilarri  Joana Campos  João C. Marques  Irene Martins 《Estuarine, Coastal and Shelf Science》2011

The present study compared the carapace structure of Carcinus maenas in two nearby sites (2 km apart) within Minho estuary, submitted to different physicochemical and ecological conditions (water temperature, pH, crabs’ density and sex ratio). The carapace structure of the carapace and chelae of the crabs presented significant differences between sampling sites (t-test; p < 0.01). The SIMPER analysis revealed that the Weight/CW and Thickness/CW ratios explained all the dissimilarities found among sites. Overall, the male carapace was proportionally thicker at station 2 (t-test; p < 0.01), while the female carapace was proportionally thicker at station 1 (t-test; p < 0.001). A thicker carapace can be advantageous when competing for food or a sexual partner. We hypothetized that, since at station 2, the density of individuals was twice higher than at station 1, it is likely that agonistic encounters are more frequent, thus favouring a thicker carapace.  相似文献   

Capturing Cold-Air Flow Using Thermal Imaging     

A. Martina Grudzielanek  Jan Cermak 《Boundary-Layer Meteorology》2015,157(2):321-332

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Five years of thermal intra-urban monitoring in Florence (Italy) and application of climatological indices     

Martina Petralli  Luciano Massetti  Simone Orlandini 《Theoretical and Applied Climatology》2011,104(3-4):349-356

This paper presents 5?years of detailed intra-urban thermal measurements carried out in Florence (Italy) by a network of 25 air temperature stations. Daily, hourly, and degree-day indices were applied to hourly data to evaluate the difference within the complex urban environment of Florence. Stations were grouped in four clusters with similar thermal regimes in each season. Our results evidence a mean difference of almost 2°C between the hottest and the coolest cluster in all seasons. Furthermore, the coolest cluster had on average more than ten frost days in winter and the hottest cluster more than 12 summer days in summer. The intra-urban difference of tropical nights was even more evident, with values of 42 versus 10?days between the hottest and the coolest cluster during the summer period. The results of this study contribute to quantify the thermal intra-urban differences in the city of Florence, suggesting important applications in plant phenology, aerobiology, human health, urban planning, and biometeorology.  相似文献   

Height transformation models from ellipsoidal into the normal orthometric height system for the territory of the City of Zagreb     

Martina Gucek  Tomislav Bašić 《Studia Geophysica et Geodaetica》2009,53(1):17-38

The paper presents the testing of the possibility of determining the heights of GPS points in the homogeneous field in the new Croatian Height Reference System (HVRS71) by using the method of height transformation. The testing was made in the area of Zagreb. As part of the field works, normal orthometric heights of 27 GPS points were determined according to the new height system, by transferring the benchmark heights using the geometric levelling method, thus obtaining GPS/levelling points of known ellipsoidal and normal orthometric heights. The GPS/levelling points served as the basis for determining the transformation models that enabled the computation of normal orthometric heights from ellipsoidal heights of any GPS point in the observed area. The empirical data used for modelling were reduced undulation dN values of GPS/levelling points. As part of the dN modelling with parametric functions, the approximation surfaces were obtained on the basis of three polynomials: FN310, FN312 and FN318. The transformation models were also tested using non-parametric Watson and Loess algorithms. The FN318 and Loess models yielded the best results.  相似文献