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  • Recently, methods for constructing Spatially Explicit Rarefaction (SER) curves have been introduced in the scientific literature to describe the relation between the recorded species richness and sampling effort and taking into account for the spatial autocorrelation in the data. Despite these methodological advances, the use of SERs has not become routine and ecologists continue to use rarefaction methods that are not spatially explicit. Using two study cases from Italian vegetation surveys, we demonstrate that classic rarefaction methods that do not account for spatial structure can produce inaccurate results. Furthermore, our goal in this paper is to demonstrate how SERs can overcome the problem of spatial autocorrelation in the analysis of plant or animal communities. Our analyses demonstrate that using a spatially-explicit method for constructing rarefaction curves can substantially alter estimates of relative species richness. For both analyzed data sets, we found that the rank ordering of standardized species richness estimates was reversed between the two methods. We strongly advise the use of Spatially Explicit Rarefaction methods when analyzing biodiversity: the inclusion of spatial autocorrelation into rarefaction analyses can substantially alter conclusions and change the way we might prioritize or manage nature reserves.
    Data Types:
    • Geospatial Data
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  • Liquefaction-induced soft-sediment deformation structures (SSDS) formed by earthquakes in southern Siberia, that were historically mentioned or monitored by instruments, are described and analyzed. Clastic dikes are the most common among all SSDS in the epicentral areas of the investigated seismic events. They are also the most reliable paleoseismic indicators in regions where cryogenic processes are intense. We suggest seven criteria that may be useful to distinguish the seismogenic clastic dikes from non-seismogenic SSDS in a single outcrop: (1) pushed up sedimentary blocks within the dike body; (2) regular distorted contacts of a dike with host sediments, reflecting cyclic loading during propagation of seismic waves; (3) turned up layers of host deposits on contacts with a dike; (4) displacement along dike contacts usually in the form of a normal fault caused by subsidence that compensates for the removed sediment; (5) a dike structure similar to a diapir; (6) filling of a clasic dike with coarser materials than the host sediments; and (7) a sediment layer extruded on the surface or between strata, similar in composition to the dike. In the extruded sandy-gravel-pebble layer, rock fragments show normal grading (from large to small clasts). In addition to these indicators, fractures may indirectly indicate the seismogenic genesis of liquefaction-induced SSDS. Due to the close spatial relationship of dikes with the fault structures of the investigated areas, they can be used to identify seismogenic fault, and the characteristics of dikes (lateral gradual changes in the frequency, size, and type of the deformations) can help to determine the epicenter, magnitude and the local intensity of the associated earthquakes.
    Data Types:
    • Geospatial Data
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  • The SW England ore region contains significant amounts of indium (In) in Early Permian granite-related skarn and lode parageneses and, to a lesser extent, Triassic epithermal “crosscourse” veins. Ore parageneses that predate granite emplacement (Devonian and Lower Carboniferous sedimentary exhalative and vein parageneses) are largely devoid of In. Cadmium (Cd) and gallium (Ga) occur widely in all sulphide-bearing parageneses across the region with sphalerite concentrations locally reaching 1.74wt% Cd and 1750ppmGa.
    Data Types:
    • Geospatial Data
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    • Tabular Data
  • The Lower-Middle Triassic Aghdarband Basin, NE Iran, consists of a strongly deformed arc-related marine succession deposited along the southern margin of Eurasia in a highly mobile tectonic context. This basin is a key-area for the study of the Cimmerian events, as the Triassic units show severe deformations, which occurred short time after the collision of Iran with Eurasia, and were sealed by the Middle Jurassic succession. In this work, we document the structural setting and evolution of this area, based on detailed mesoscopic structural analyses of faults and folds, paleostress reconstruction and revision of the Triassic stratigraphy. The Triassic sequences are deeply involved in a N-verging thrust stack interacting with an important left-lateral transpressional fault zone characterized by strike-slip faults, vertical folds and high angle reverse faults generating intricate positive flowers. Systematic folds asymmetry indicates that they developed in a left-lateral transpressional zone coeval to thrust imbrication to the south, due to a marked strain partitioning.
    Data Types:
    • Geospatial Data
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    • Tabular Data
  • A river section at Słupia Nadbrzeżna, central Poland, has been proposed as a candidate Turonian – Coniacian (Cretaceous) GSSP, in combination with the Salzgitter-Salder quarry section of Lower Saxony, Germany. Results of a high-resolution (25 cm) palynological study of the boundary interval in the Słupia Nadbrzeżna section are presented. Terrestrial palynomorphs are rare; marine organic-walled dinoflagellate cysts dominate the palynological assemblage. The dinoflagellate cyst assemblage has a low species richness (5–11 per sample; total of 18 species recorded) and diversity (Shannon index H = 0.8–1.4), dominated by four taxa: Circulodinium distinctum subsp. distinctum; Oligosphaeridium complex; Spiniferites ramosus subsp. ramosus; Surculosphaeridium longifurcatum. Declining proportions of O. complex and S. ramosus subsp. ramosus characterise the uppermost Turonian, with an increased dominance of S. longifurcatum in the lower Coniacian. The Turonian – Coniacian boundary interval includes an acme of C. distinctum subsp. distinctum in the upper Mytiloides scupini Zone, a dinoflagellate cyst abundance maximum in the Cremnoceramus walterdorfensis walterdorfensis Zone, and the highest occurrence of Senoniasphaera turonica in the basal Coniacian lower Cremnoceramus deformis erectus Zone. Most previously reported Turonian – Coniacian boundary dinoflagellate cyst marker species are absent; a shallow-water oligotrophic epicontinental depositional setting, remote from terrestrial influence, likely limited species diversity and excluded many taxa of biostratigraphic value.
    Data Types:
    • Geospatial Data
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  • The concentrations of ten metals (As, Cd, Cu, Fe, Hg, K, Na, Pb, Sn and Zn) were monitored in coastal seawater and biomass of the seaweed Alaria esculenta from Aughinish Bay on the West coast of Ireland during March–June 2014 in order to study their temporal variations and assimilation efficiencies and to assess the ecological quality of these ecosystems. Seawater and A. esculenta showed significant temporal variations in their metal concentrations during March–June 2014 and A. esculenta accumulated more efficiently Fe and Zn, but showed low sensitivity to Na and K. On the other hand, A. esculenta showed no active detoxication mechanisms for Cd and Pb, but no saturation point was observed during this work to any metal. Considering metal concentrations bioaccumulated by A. esculenta, the Irish coast of Aughinish Bay was always ecologically classified as “Class I – Unpolluted” during March–June 2014. The significant correlations between seawater and A. esculenta obtained to all metals proved that this seaweed species: (i) is a suitable biomonitor of metal contamination in Irish coasts; (ii) it can be included in the European Environmental Specimen Banks and (iii) it can be used in European Real-Time Environmental Monitoring Networks.
    Data Types:
    • Geospatial Data
    • Image
    • Tabular Data
  • Mountain regions meet an increasing demand for pleasant landscapes, offering many cultural ecosystem services to both their residents and tourists. As a result of global change, land managers and policy makers are faced with changes to this landscape and need efficient evaluation techniques to assess cultural ecosystem services. This study provides a spatially explicit modelling approach to estimating aesthetic landscape values by relating spatial landscape patterns to human perceptions via a photo-based survey. The respondents attributed higher aesthetic values to the Alpine landscape in respect to areas with settlements, infrastructure or intensive agricultural use. The aesthetic value of two study areas in the Central Alps (Stubai Valley, Austria and Vinschgau, Italy) was modelled for 10,215 viewpoints along hiking trails according to current land cover and a scenario considering the spontaneous reforestation of abandoned land. Viewpoints with high aesthetic values were mainly located at high altitude, allowing long vistas, and included views of lakes or glaciers, and the lowest values were for viewpoints close to streets and in narrow valleys with little view. The aesthetic values of the reforestation scenario decreased mainly at higher altitudes, but the whole area was affected, reducing aesthetic value by almost 10% in Stubai Valley and 15% in Vinschgau. Our proposed modelling approach allows the estimation of aesthetic values in spatial and qualitative terms for most viewpoints in the European Alps. The resulting maps can be used as information and the basis for discussion by stakeholders, to support the decision-making process and landscape planning. This paper also discusses the role of mountain farming in preserving an attractive landscape and related cultural values.
    Data Types:
    • Geospatial Data
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    • Tabular Data
    • Document
  • This work shows a downscaling approach for environmental changes study using multi- and hyper-spectral remote sensing data. The study area, located in the south-east of Mt. Vesuvius National Park, has been affected by two main activities during the last decades: mining and consecutive municipal solid waste dumping. These activities had an environmental impact in the neighbouring areas releasing dust and gaseous pollutants in the atmosphere and leachate into the ground. The approach integrated remote sensing data at different spectral and spatial resolutions. Landsat TM images were adopted to study the changes that occurred in the area using environmental indices at a wider temporal scale. In order to identify these indices in the study area, two high spatial and spectral resolution MIVIS aerial images were adopted. The first image, acquired in July 2004, describes the environmental situation after the anthropic activities of extraction and dumping in some sites, while the second image acquired in 2010 reflects the situation after the construction of new landfill in an old quarry. The spectral response of soil and vegetation was applied to interpret stress conditions and other environmental anomalies in the study areas. Some Warning Zones were defined by “core” and “neighbouring” of the anthropic area. Different classification methods were adopted in order to characterize the study area: Spectral Angle Mapper (SAM) classification provided local covers, while Linear Spectral Unmixing Analysis (LSMA) identified main fractions changes of vegetation, substrate and dark surfaces. The change detection of spectral indices, supported by thermal anomalies, highlighted potential stressed areas.
    Data Types:
    • Geospatial Data
    • Image
    • Tabular Data
  • In the framework of flood risk assessment, vulnerability is a key concept to assess the susceptibility of elements at risk. Besides the increasing amount of studies on flash floods available, in-depth information on vulnerability in Mediterranean countries was missing so far. Moreover, current approaches in vulnerability research are driven by a divide between social scientists who tend to view vulnerability as representing a set of socio-economic factors, and natural scientists who view vulnerability in terms of the degree of loss to an element at risk. Further, vulnerability studies in response to flash flood processes are rarely answered in the literature. In order to close this gap, this paper implemented an integrated vulnerability approach focusing on residential buildings exposed to flash floods in Greece. In general, both physical and social vulnerability was comparable low, which is interpreted as a result from (a) specific building regulations in Greece as well as general design principles leading to less structural susceptibility of elements at risk exposed, and (b) relatively low economic losses leading to less social vulnerability of citizens exposed. The population show high risk awareness and coping capacity to response to natural hazards event and in the same time the impact of the events are quite low, because of the already high use of local protection measures. The low vulnerability score for East Attica can be attributed especially to the low physical vulnerability and the moderate socio-economic well-being of the area. The consequence is to focus risk management strategies mainly in the reduction of the social vulnerability. By analysing both physical and social vulnerability an attempt was made to bridge the gap between scholars from sciences and humanities, and to integrate the results of the analysis into the broader vulnerability context.
    Data Types:
    • Geospatial Data
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    • Tabular Data
  • Ultimately, the fate of mangrove forests depends on substrate-elevation gains keeping pace with relative sea-level rise (RSLR). Some of the world's largest mangrove forests occur on tectonically active margins, river deltas and sedimentary basins where sea-level trends are largely controlled by vertical land motion (i.e., subsidence), so that RSLR can be markedly higher than sea-level rise induced by climate warming. The Rod Surface Elevation Table — Marker Horizon (RSET-MH) method has been applied globally to evaluate coastal-wetland resilience to SLR by quantifying net rates of elevation change relative to a benchmark. A limitation of the RSET method is that the stability of the benchmark (i.e., vertical trend) is unknown and RSLR in wetlands is typically inferred from regional tide-gauge records. In the present study, we evaluate RSLR in a rapidly-subsiding Avicenna marina mangrove forest with a large terrigenous sediment supply (Firth of Thames, New Zealand) using independent and complimentary methods: (1) campaign-GPS surveys of the stability of three RSET benchmarks driven 18m into unconsolidated sediment, a tide gauge some 10km distant and a reference station located on basement rock (2007–2016) that are tied to a network of satellite-based geodetic sites; and (2) 137Cs-validated 210Pb sediment accumulation rates (SAR) measured in cores as a proxy for RSLR. The similarity of deep-subsidence rates at the RSET benchmarks located several-hundred metres apart (7.7±0.5 to 9.4±0.5mmyr−1) provides confidence in these results. These subsidence rates are two- to five-fold higher than recorded at the nearby tide gauge (3.6±0.7mmyr−1) and reference station (1.6±0.5mmyr−1). Weighted-average 210Pb SAR of 9.9mm and 9.3mmyr−1 yield similar estimates of deep subsidence (i.e., 8.4 and 6.9mmyr−1+SLR adjusted for vertical land motion), indicating that this geological process is the major driver of the long-term sea-level trend in the mangrove forest. Our findings suggest that regional tide gauge records may not provide reliable estimates of RSLR for all coastal wetlands due to local subsidence associated with natural processes and human activities. Subsidence rates and RSLR within coastal wetlands can be evaluated using campaign-GPS surveys of RSET benchmarks and independently from longer-term sedimentary records. Finally, evaluations of the resilience of coastal wetlands to rising sea levels over the coming decades must be based on measurements of RSLR from these systems themselves.
    Data Types:
    • Geospatial Data
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    • Tabular Data
    • Document
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