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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:
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In this paper we search for conditions on age-structured differential games to make their analysis more tractable. We focus on a class of age-structured differential games which show the features of ordinary linear-state differential games, and we prove that their open-loop Nash equilibria are sub-game perfect. By means of a simple age-structured advertising problem, we provide an application of the theoretical results presented in the paper, and we show how to determine an open-loop Nash equilibrium.
Data Types:
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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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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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It is known that rocky macroalgae distribution depends on several abiotic factors, but little attention has been given to geomorphological influences. This paper analysed the relation between geomorphological variables (active processes, coastal morphology, coastal orientation and lithology) and rocky intertidal macroalgae species at a local scale. Thirteen sites were sampled along the coast of Cantabria (North Spain) in order to obtain covers of macroalgae species. Multivariate analysis and logistic regression were applied, predicting the probability occurrence of macroalgae species as a response to the predictor geomorphological variables. Our results showed that coastal morphology and coastal orientation were the principal geomorphological factors explaining the structure of macroalgae communities. The most significant differences in substrate preferences were found between Bifurcaria bifurcata, that appears in wave-cut platforms oriented towards the east, and Corallina officinalis/Ellisolandia elongata and Gelidium spinosum, which are found in cliffs oriented towards the north and west. Although these variables help to characterise species distribution, their predictive value is still limited, possibly due to other factors influencing macroalgae. Thus, some of the geomorphological variables studied here are among the environmental factors that determined the distribution of intertidal macroalgae communities at a local scale, even if not always in a direct way.
Data Types:
  • Geospatial Data
  • Image
  • Tabular Data
  • Document
Landslides are widespread phenomena that contribute to shape the landscape. Assessing the time sequence of landslide activity during the Holocene can help (i) better frame the present day landslide distribution in the wider context of climate change and (ii) better define landslide hazard to take adequate mitigation measures to preserve the elements at risk such as archaeological heritage and currently used structures and infrastructures. Rigorous image interpretation criteria applied to the interpretation of remote sensing images can be a valuable tool to derive information on landslide spatial and temporal distribution. However, it only allows to broadly estimate the relative age of landslides based on their morphologic signature. In this work, we investigate the topological relations between landslides and archaeological sites for nine selected settlements in the Moldavian Plateau, situated on ridges and hillslopes. Landslides and sites were mapped using high resolution LiDAR DEMs and extensive field validation activities. Landslides were classified as very old (relict), old, and recent, according to their morphologic appearance. We argue the possibility of (i) assigning a relative age to the three main classes of landslides as they appear on the present day topography, and (ii) assessing the landslide activity during the Holocene. Using this information, we set up a model of landslide evolution during the Holocene for the lowland of Eastern Carpathians. Based on collected data, we cannot exclude the Pleistocene age for some very old landslides, whereas the old and recent landslides appeared during the Holocene. We think this approach can be extended to other archaeological sites of the study area, and to other areas. Furthermore, similar studies can prove useful for landslide hazard analyses, helping to adopt adequate protection and mitigation measures, framed in a climate change scenario.
Data Types:
  • Geospatial Data
  • Image
  • Tabular Data
The Tatra Mountains are the highest massif in the Carpathian mountain arc (2655 m) and represent a typical alpine landscape developed in the course of Pleistocene glaciations, but are not glacierized today. The glacial relief of the massif offers an abundance of topographic depressions (cirque overdeepenings, morainic closed depressions) where sedimentary sequences may potentially reveal paleoenvironmental changes that may have occurred since the glaciers' retreat from the Last Glacial Maximum position (∼26–18 ka). We present a review of Late Glacial and Holocene sedimentary archives from the Tatra Mountains collected in the Polish and non-Polish literature. The data sets (40 sites) included 21 lake, 13 peat bog, and 6 colluvial sediment sites. The entire listed sediment sequence features radiometric datings or at the very least a chronological framework is inferred from the biostratigraphy. The oldest sampled sedimentary sequences were dated back to the Oldest Dryas and were obtained from the deepest glacial lakes located in the subalpine zone (up to 1700 m). Shallow lakes (<10 m) and morainic closed depressions do not reveal sediments older than the Holocene. This can be linked with dry climate conditions and unfavorable hydrologic regimes during the Late Glacial when the studied depressions remained dry over the long term following deglaciation, irrespective of elevation and position in the glaciated valley system. For the Holocene, several millennial-scale phases of climate humidity and increased debris flow activity were identified. The intensification of debris flows is indicated at 9–7.5 ka and during the mid- to late Holocene (at ca. 6 ka, 3.5 ka, 2 ka, after 300 AD, 800–1000 AD, and LIA), separated by relatively stable climate conditions during the 'Holocene thermal optimum' (7.5–6 ka). The LIA in the Tatra Mountains was a relatively long (1220–1925 AD) and climatically unstable period, with a cold and dry first phase (1220–1540 AD), followed by a cold and humid phase (1540–1925 AD). During the modern warm period, renewed intensification of extreme slope processes has been recorded after 1970 AD.
Data Types:
  • Geospatial Data
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Although the climate development over the Holocene in the Northern Hemisphere is well known, palaeolimnological climate reconstructions reveal spatiotemporal variability in northern Eurasia. Here we present a multi-proxy study from north-eastern Siberia combining sediment geochemistry, and diatom and pollen data from lake-sediment cores covering the last 38,000 cal. years. Our results show major changes in pyrite content and fragilarioid diatom species distributions, indicating prolonged seasonal lake-ice cover between ∼13,500 and ∼8900 cal. years BP and possibly during the 8200 cal. years BP cold event. A pollen-based climate reconstruction generated a mean July temperature of 17.8 °C during the Holocene Thermal Maximum (HTM) between ∼8900 and ∼4500 cal. years BP. Naviculoid diatoms appear in the late Holocene indicating a shortening of the seasonal ice cover that continues today. Our results reveal a strong correlation between the applied terrestrial and aquatic indicators and natural seasonal climate dynamics in the Holocene. Planktonic diatoms show a strong response to changes in the lake ecosystem due to recent climate warming in the Anthropocene.
Data Types:
  • Geospatial Data
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  • Tabular Data
Development of a clearer understanding of the causes and consequences of environmental change is an important issue globally. The consequent demand for objective, reliable and up-to-date environmental information has led to the establishment of long-term integrated environmental monitoring programmes, including the UK's Environmental Change Network (ECN). Databases form the core information resource for such programmes. The UK Environmental Change Network Data Centre manages data on behalf of ECN (as well as other related UK integrated environmental monitoring networks) and provides a robust and integrated system of information management. This paper describes how data are captured – through standardised protocols and data entry systems – as well more recent approaches such as wireless sensors. Data are managed centrally through a database and GIS. Quality control is built in at all levels of the system. Data are then made accessible through a variety of data access methods – through bespoke web interfaces, as well as third-party data portals. This paper describes the informatics approach of the ECN Data Centre which aims to develop a seamless system of data capture, management and data access interfaces to support research.
Data Types:
  • Geospatial Data
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This paper is a three-part assessment of the history of public housing in Richmond, Virginia and an account of current efforts to create a progressive model for public housing redevelopment in the city. Part One provides a short history of Richmond's creation of nearly exclusively African-American public housing in the East End of the city in the 1940s, 1950s, and 1960s, and describes a regional context in which virtually all public housing in the entire metropolitan area is located within a central city that is home to just one-sixth of the overall metro population. Part Two provides an account of the Blackwell public housing complex in Richmond under the Hope VI program, beginning in the late 1990s, and an account of the tenant activism that arose in response to the many problems and shortcomings with that project. That activism later resulted in the tenant-led coalition Residents of Public Housing in Richmond Against Mass Evictions (or RePHRAME). Together non-profit and tenant activists in RePHRAME have collaborated over the past several years to challenge redevelopment practices that threaten to diminish the number of public housing units in the city. Part Three is an in-progress report on an effort we are each personally involved in that includes participation by RePHRAME members as well as several community organizations and leaders that have been part of the RePHRAME coalition: to create a new resident-driven, progressive redevelopment process for the city. This process aims to build consensus among city policymakers and many tenants that redevelopment of the city's highly concentrated public housing units for the sake of improving opportunities and living conditions for residents is a moral imperative. Recognizing and articulating the history of segregation, mismanagement, and deep distrust between residents and public authorities, this process takes seriously the deep-seated and legitimate concerns of tenants with the aim of assuring much more positive outcomes in future redevelopment processes.
Data Types:
  • Geospatial Data
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