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121.
Giancarlo Biotto Lucia Gobbo Elisa Furlan Sonia Valenti Roberto Rosselli 《International journal of geographical information science》2013,27(10):1233-1244
This work deals with the identification of potentially contaminated areas using remote sensing, geographic information systems (GIS) and multi‐criteria spatial analysis. The identification of unknown illegal landfills is a crucial environmental problem in all developed and developing countries, where a large number of illegal waste deposits exist as a result of fast, and relatively unregulated, industrial growth over the past century. The criteria used to perform the spatial analysis are here selected by considering the characteristics which are ‘desirable’ for an illegal waste disposal site, chiefly related to the existence of roads for easy access and to a low population density which facilitates unnoticed dumping of illegal waste materials. A large dataset describing known legal and illegal landfills and the context of their location (population, road network, etc.) was used to perform a spatial statistical analysis to select factors and criteria allowing for the identification of the known waste deposits. The final result is a map describing the likelihood of an illegal waste deposit to be located at any arbitrary location. Such a probability map is then used together with remote sensing techniques to narrow down the set of possibly contaminated sites (Silvestri and Omri, 2008), which are candidates for further analyses and field investigations. The importance of the integration of GIS and remote sensing is highlighted and represents a key instrument for environmental management and for the spatially‐distributed characterization of possible uncontrolled landfill sites. 相似文献
122.
Lucia Maria Seebach Peter Strobl Jesus San Miguel-Ayanz Annemarie Bastrup-Birk 《International journal of geographical information science》2013,27(11):1865-1884
Detailed and harmonized information on spatial forest distribution is an essential input for forest-related environmental assessments, in particular, for biomass and growing stock modeling. In the last years, several mapping approaches have been developed in order to provide such information for Europe in a harmonized way. Each of these maps exhibits particular properties and varies in accuracy. Yet, they are often used in parallel for different modeling purposes. A detailed spatial comparison seemed necessary in order to provide information on the advantages and limitations of each of these forest cover maps in order to facilitate their selection for modeling purposes. This article confronts the high-resolution forest cover map recently developed by the Joint Research Centre for the year 2000 (FMAP2000) with previously existing maps for the same time period: the CORINE Land Cover 2000 (CLC2000) and the Calibrated European Forest Map 1996 (CEFM1996). The spatial comparison of these three maps was carried out based on forest proportion maps of 1 km derived from the original maps. To characterize differences according to biogeographic regions, two criteria were used: detail of thematic content within each map and local spatial agreement. Concerning thematic content, CLC2000 displayed a surfeit of non-forested areas at the cost of low forest proportions, while FMAP2000 showed a more balanced distribution likely to preserve more detail in forest spatial pattern. Good spatial agreement was found for CLC2000 and FMAP2000 within about 70% of the study area, while only 50% agreement was found when compared with CEFM1996. The largest spatial differences between all maps were found in the Alpine and Mediterranean regions. Reasons for these might be different input data and classification techniques and, in particular, the calibration of CEFM1996 to reported national statistics. 相似文献
123.
Constantin Cosma Alexandra Cucoş Botond Papp Robert Begy Tiberiu Dicu Mircea Moldovan Lucia Adina Truţă Dan Constantin Niţă Bety-Denissa Burghele Liviu Suciu Carlos Sainz 《Acta Geophysica》2013,61(4):859-875
B?i?a-?tei mine is an open pit mine in NW Romania (West Carpathian Mountains). It was the largest surface uranium deposit in the world. Two means of uranium transport and dissemination were used over time. The first was the natural way, represented by transportation of geological sediments by Cri?ul-B?i?a River that crosses the B?i?a surface deposit. These sediments were used as building materials (stone, gravel, sand). The second way was related to the people living in this valley, who used also the uranium waste as building material. The preliminary indoor radon concentrations measured in the buildings ranged from 40 to 4000 Bq m?3 with a mean value of 241 Bq m?3. A focused radon survey facilitated the selection of 20 houses with the highest indoor radon that were therefore proposed for remediation. To find the radon sources of these houses, systematic investigations on radon were performed. The remedial measures for these 20 houses were tested on a chosen pilot house. 相似文献
124.
Laura?SandriEmail author Warner?Marzocchi Lucia?Zaccarelli 《Bulletin of Volcanology》2004,66(3):263-275
The complexity of the processes responsible for volcanic eruptions makes a theoretical approach to forecasting the evolution of volcanic unrest rather difficult. A feasible strategy for this purpose appears to be the identification of possible repetitive schemes (patterns) in the pre-eruptive unrest of volcanoes. Nevertheless, the limited availability and the heterogeneity of pre-eruptive data, and the objective difficulty in quantitatively recognizing complex pre-eruptive patterns, make this task very difficult. In this work we address this issue by using a pattern recognition approach applied to the seismicity recorded during 217 volcanic episodes of unrest around the world. In particular, we use two non-parametric algorithms that have proven to give satisfactory results in dealing with a small amount of data, even if not normally distributed and/or characterized by discrete or categorical values. The results show evidence of a longer period of instability in the unrest preceding an eruption, compared to isolated unrest. This might indicate, even if not necessarily, a difference in the energy of processes responsible for the two types of unrest. However, if the unrest is followed by an eruption, it seems that the seismic energy released during the unrest (parameterized by the duration of the swarm and the maximum magnitude recorded) is not indicative of the magnitude of the impending eruption. We also found that, in general, unrest followed by the largest explosive eruptions have a longer repose time than those related to moderate eruptions. This evidence supports the fact that the occurrence of a large eruption needs a sufficient amount of time after the last event in order to re-charge the feeding system and to achieve a closed-conduit regime so that a sufficiently large amount of gas can be accumulated.Editorial responsibility: T. Druitt 相似文献
125.
Lucia Wick Jacqueline F.N. van Leeuwen Willem O. van der Knaap André F. Lotter 《Journal of Paleolimnology》2003,30(3):261-272
Pollen and plant macrofossils were analysed at Sägistalsee (1935 m asl), a small lake near timber-line in the Swiss Northern Alps. Open forests with Pinus cembra and Abies alba covered the catchment during the early Holocene (9000–6300 cal. BP), suggesting subcontinental climate conditions. After the expansion of Picea abies between 6300 and 6000 cal. BP the subalpine forest became denser and the tree-line reached its maximum elevation at around 2260 m asl. Charcoal fragments in the macrofossil record indicate the beginning of Late-Neolithic human impact at ca. 4400 cal. BP, followed by a extensive deforestation and lowering of the forest-limit in the catchment of Sägistalsee at 3700 cal. BP (Bronze Age). Continuous human activity, combined with a more oceanic climate during the later Holocene, led to the local extinction of Pinus cembra and Abies alba and favoured the mass expansion of Picea and Alnus viridis in the subalpine area of the Northern Alps. The periods before 6300 and after 3700 cal. BP are characterised by high erosion activity in the lake's catchment, whereas during the phase of dense Picea-Pinus cembra-Abies forests (6300–3700 cal. BP) soils were stable and sediment-accumulation rates in the lake were low. Due to decreasing land-use at higher altitudes during the Roman occupation and the Migration period, forests spread beween ca. 2000 and 1500 cal. BP, before human impact increased again in the early Middle Ages. Recent reforestation due to land-use changes in the 20th century is recorded in the top sediments. Pollen-inferred July temperature and annual precipitation suggest a trend to cooler and more oceanic climate starting at about 5500 cal. BP. 相似文献
126.
Maurizio Gaetani Lucia Angiolini Alda Nicora Dario Sciunnach Patrick Le Fort Seifnullah Tanoli Asif Khan 《International Journal of Earth Sciences》1996,85(4):683-704
During the summer of 1992 a geological expedition crossed the northern Karakorum range in northern Pakistan, from the Chitral
to Karambar valleys, from the villages of Mastuj to Imit. Some of the areas visited were geologically unknown. A number of
structural units were crossed, belonging to the Karakorum block or to other crustal blocks north of it. They are: (a) the
axial batholith, in which three plutonic bodies have been identified, and (b) the northern sedimentary belt (NSB), in which
three major tectonostratigraphic units form thrust stacks dipping to the north. Their internal stratigraphy and structural
style are partly different. The most complete contains a crystalline basement, transgressed by a marine succession during
the Early Ordovician. The youngest strata are represented by the Reshun conglomerate, of inferred Cretaceous age. The northernmost
unit of the NSB is tightly folded, whereas the central one forms a monocline. Vertical faults, mainly strike-slip, dissect
the thrusted slabs. Metamorphic deformation is absent or reaches only the anchizone in the studied sector of the Karakorum
NSB. To the north of the Karakorum proper there are several other tectonic units, separated by vertical faults. They are,
from south to north: (a) the Taš Kupruk zone, with metavolcanics of basaltic to latibasaltic composition; (b) the Atark unit,
mostly consisting of massive carbonate rocks of Mesozoic age; and (c) the Wakhan slates which consist of a thick widespread
succession of dark slates, metasiltites and sandstones. The fine-grained elastic rocks are supposed to be Palaeozoic to Early
Triassic in age. The Wakhan slates are intruded by plutons belonging to the East Hindu Kush batholith, from which a single
K/Ar age on muscovite gave a Jurassic age. 相似文献
127.
128.
In this paper, we explore migration aspects of the 1995 Quebec Sovereignty Referendum with data from a survey administered to non-francophones in Montreal two weeks prior to the Referendum. While the Quebec sovereignty issue has been around for some time and earlier exodus from the province, particularly among anglophones, is largely regarded as “forced” in some way, this study neither confirms the 1995 Sovereignty Referendum as a paramount factor in explaining outmigration from Quebec nor points to a real reluctance to leave Montreal. The decision to move is influenced by the interplay of a multitude of factors. The political influence is only an added factor to longstanding economic decline and cultural clash. Moreover, if there is any impulsion, the degree varies among different cultural and socioeconomic groups. 相似文献
129.
Lucia Fanning Robin Mahon Patrick McConney Jorge Angulo Felicity Burrows Bisessar Chakalall Diego Gil Milton Haughton Sherry Heileman Sergio Martínez L’ouverture Ostine Adrian Oviedo Scott Parsons Terrence Phillips Claudia Santizo Arroya Bertha Simmons Cesar Toro 《Marine Policy》2007
A large marine ecosystem (LME) governance framework, developed from a need to effectively address the sustainable management of the shared living marine resources of the Caribbean, is proposed. The framework is based on four propositions and focuses on a linked examination of two well-known components of LME-level governance: the policy cycle process by which decisions are made and the multi-level nature of LMEs. It accommodates the diversity of policy cycles at multiple levels and the linkages among them required for effective governance of LMEs. The framework takes into account of factors such as context, purpose, jurisdictional scale, capacity and complexity and provides a means to identify critical areas for intervention. 相似文献
130.
Benthic Community and Sediment Types: A Structural Analysis 总被引:2,自引:0,他引:2
Eugenio Fresi Maria Cristina Gambi Silvano Focardi Roberto Bargagli Franco Baldi Lucia Falciai 《Marine Ecology》1983,4(2):101-121
Abstract. The distribution of the macrobenthic community, in relation to various physical and chemical characteristics of the sediment, was studied along the coast of Southern Tuscany (Central Tyrrhenian) in an area under the influence of the Ombrone River outflow.
The zonation of the benthos was found to be primarily under the control of a gradient of water movement, as is reflected by variations in the sediment structure from the coast to the open sea. This correlation is somehow influenced by secondary gradients such as the degree of mixing of the sediment and the deposition of terrigenous materials along the river plume. 相似文献
The zonation of the benthos was found to be primarily under the control of a gradient of water movement, as is reflected by variations in the sediment structure from the coast to the open sea. This correlation is somehow influenced by secondary gradients such as the degree of mixing of the sediment and the deposition of terrigenous materials along the river plume. 相似文献