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131.
Crisis mapping is a legitimate component of both crisis informatics and disaster risk management. It has become an effective tool for humanitarian workers, especially after the earthquake in Haiti in 2010. Ushahidi is among the many mapping platforms on offer in the growing field of crisis mapping, and involves the application of crowdsourcing to create online and interactive maps of areas in turmoil. This paper presents the Crisis Map of the Czech Republic, which is the first such instrument to be deployed nationwide in Central Europe. It describes the methodologies used in the preparatory work phase and details some practices identified during the creation and actual employment of the map. In addition, the paper assesses its structure and technological architecture, as well as its potential possible development in the future. Lastly, it evaluates the utilisation of the Crisis Map during the floods in the Czech Republic in 2013.  相似文献   
132.
The concentrations of polybrominated diphenyl ethers (PBDEs) 17, 28, 47, 49, 66, 85, 99, 100, 153, 154, and 183 were determined in ringed seal blubber from central East Greenland collected in 1986, 1994, 1999 and during the period 2001 to 2004. The trend of PBDEs was compared with the trends of polychlorinated biphenyls (PCBs) 28, 31, 52, 101, 105, 118, 138, 153, 156, and 180 during the same period. The levels of sigmaPBDE in East Greenland ringed seals ranged from 21.8 ng g(-1) lipid weight (1w) in 1986 to 39.3 ng g(-1) lw in 2001 and are among the highest observed in ringed seal from the Arctic. The dominating congeners were BDE-47 (75.4%) and BDE-99 (9.7%). The concentrations of PBDEs and PCBs increased with the age of the seals, and therefore only young seals < or =4 years old) were included in the temporal trend analyses. No significant trend (p > 0.14) was observed in sigmaPBDE or the congeners BDE 28, 47 and, 99 during the period while sigmaPCB decreased significantly (p = 0.004) over the period from 1986 to 2004 with an estimated annual rate of 4.3%.  相似文献   
133.
The article describes a riverscape approach based on landscape ecology concepts, which aims at studying the multiscale relationships between the spatial pattern of stream fish habitat patches and processes depending on fish movements. A review of the literature shows that few operational methods are available to study this relationship due to multiple methodological and practical challenges inherent to underwater environments. We illustrated the approach with literature data on a cyprinid species (Barbus barbus) and an actual riverscape of the Seine River, France. We represented the underwater environment of fishes for different discharges using two-dimensional geographic information system-based maps of the resource habitat patches, defined according to activities (feeding, resting, and spawning). To quantify spatial patterns at nested levels (resource habitat patch, daily activities area, subpopulation area), we calculated their composition, configuration, complementation, and connectivity with multiple spatial analysis methods: patch metrics, moving-window analysis, and least cost modeling. The proximity index allowed us to evaluate habitat patches of relatively great value, depending on their spatial context, which contributes to the setting of preservation policies. The methods presented to delimit potential daily activities areas and subpopulation areas showed the potential gaps in the biological connectivity of the reach. These methods provided some space for action in restoration schemes.  相似文献   
134.
Road traffic emits a cocktail of pollutants that can influence the vegetation and plant diversity in neighboring areas. However, the recovery potential of bryophytes after traffic abandonment is still little explored. In addition, the effects of the main pollutants of road verges, such as metals and salinity, on moss flora need to be investigated. In our study, we compared the moss richness and diversity in two closely related veteran tree allees of high conservation importance. The allees in Gry?ów and Lubrza, Poland, were chosen because of their similarity in age, geographical location, type of surrounding areas, and tree species. The only difference was that the trees in Gry?ów had not been exposed to direct road pollution for almost 30 years. The moss richness and diversity differed significantly between the sites. Altogether, 20 moss species were recorded on 229 trees, 17 species in Gry?ów (abandoned road), and 13 in Lubrza (busy road). We found considerable differences between moss cover on the road-facing and opposite sides of tree trunks. In Lubrza, mosses on the road-facing side were very scarce. The moss cover in Gry?ów was highly balanced between trunk sides as well as among trunk heights. Typical epiphytic species such as Bryum moravicum, Dicranoweisia cirrata, Leskea polycarpa, and Orthodicranum tauricum preferred the Gry?ów tree stands, where they were present in numbers almost twice as high as that at Lubrza. The study shows that constructing a bypass road could be an effective conservation measure for veteran tree protection with their epiphytic moss flora.  相似文献   
135.
We studied landscape dynamics for three time periods (<1950, 1965, and 1997) along a gradient of agricultural intensity from highly intensive agriculture to forested areas in southern Québec. Air photos were analyzed to obtain long-term information on land cover (crop and habitat types) and linear habitats (hedgerows and riparian habitats) and landscape metrics were calculated to quantify changes in habitat configuration. Anthropogenic areas increased in all types of landscapes but mostly occurred in the highly disturbed cash crop dominated landscape. Perennial crops (pasture and hayfields) were largely converted into annual crops (corn and soybean) between 1965 and 1997. The coalescence of annual crop fields resulted in a more homogeneous agricultural landscape. Old fields and forest cover was consistently low and forest fragmentation remained stable through time in the intensive agriculture landscapes. However, forest cover increased and forest fragmentation receded in the forest-dominated landscapes following farm abandonment and the transition of old fields into forests. Tree-dominated hedgerows and riparian habitats increased in areas with intensive agriculture. Observed changes in land cover classes are related to proximate factors, such as surficial deposits and topography. Agriculture intensification occurred in areas highly suitable for agriculture whereas farm abandonment was observed in poor-quality agriculture terrains. Large-scale conversion of perennial crops into annual crops along with continued urbanization exerts strong pressures on residual natural habitats and their inhabiting wildlife. The afforestation process occurring in the more forested landscapes along with the addition of tree-dominated hedgerows and riparian habitats in the agriculture-dominated landscapes should improve landscape ecological value.  相似文献   
136.
Levels and temporal trends of the hexachlorocyclohexane isomers alpha-, beta- and gamma-HCH were analysed in blubber of juvenile ringed seals from West Greenland (1994 to 2006) and juvenile and adult ringed seals from East Greenland (1986 to 2006). No significant differences in the concentration levels in the juvenile seals were found between East and West Greenland for any of the three isomers. alpha-HCH concentrations were not significantly different between juvenile and adult ringed seals from East Greenland, whereas beta- and gamma-HCH concentrations were significantly higher in adult ringed seals. alpha- and beta-HCH in Greenland ringed seals were approximately a factor two lower than in the Canadian Arctic, and alpha-HCH was a factor 2-3 higher than in ringed seals from an area east of Svalbard, Norway. Annual decreases in ringed seals from Greenland during the study periods were detected to be 9.1-11.7%, 1.4-3.9% and 6.0-6.4% for alpha-, beta- and gamma-HCH, respectively, being quite similar in both East and West Greenland. Similar levels and trends in East and West Greenland support the general understanding of the pathways of HCH isomers to and in the Arctic.  相似文献   
137.
The paper presents the analysis of anthropogenical modifications of the landscape in relation to the course and consequences of floods. The research was conducted in the Otava river basin which represents the core zone of the extreme flood in August 2002 in Central Europe. The analysis was focused on the key indicators of landscape modification potentially affecting the runoff process - the long-term changes of land-use, changes of land cover structure, land drainage, historical shortening of the river network and the modifications of streams and floodplains. The information on intensity and spatial distribution of modifications was derived from different data sources - historical maps, available GIS data, remote sensing and field mapping. The results revealed a high level of spatial diversity of anthropogenical modifications in different parts of the river basin. The intensive modifications in most of indicators were concentrated in the lowland region of the river basin due to its agricultural use; however important changes were also recorded in the headwater region of the basin. The high spatial diversity of the modifications may result in their varying effect on the course and consequences of floods in different parts of the river basin. This effect is demonstrated by the cluster analysis based on the matrix of indicators of stream and floodplain modification, physiogeographical characteristics and geomorphological evidences of the flood in August 2002, derived from the individual thematic layers using GIS.  相似文献   
138.
We analyzed the management, resource use and conservation of the Ankarafantsika National Park (Madagascar) to develop a management plan, which provides a sustainable development strategy of the area while empowering the local residents. Using qualitative methodology we performed interviews with villagers and local organizations to assess the park’s successes and failures from local stakeholders’ perspectives. People living in a village with a permanent Madagascar National Parks (MNP) agent are more favorable to and supportive of the park conservation. People living in the park are supportive but are more divided. On the other hand, people living on the periphery of the park see conservation as more of a burden. Strategies like more equitable distribution of wealth, environment improvement and decentralization of power are discussed to achieve a more sustainable management plan based on community natural resources management. Short-term, medium, and long-term interventions from park authorities are needed to ensure the cooperation of local people in conservation endeavors.  相似文献   
139.
There is a lack of information regarding persistent organic pollutants (POPs) in soil from Slovakia. This paper reports the concentrations of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), 12 dioxin-like polychlorinated biphenyls (dl-PCBs) and 6 indicator PCBs associated with 32 soil samples collected in 2007 from areas in the vicinity up to several kilometres from four selected industrial PCDD/F sources in Slovakia and one background area.The results show that the total WHO1998-PCDD/F/dl-PCB-TEQ concentrations varied from 0.34 to 18.05 pg g−1 dry weight (dw) and the average total TEQ concentrations in samples collected at the Šala, Košice, Krompachy and Dubová areas were 3.18, 2.64, 7.80, and 3.19 pg g−1 dw respectively. The average of the total WHO1998-TEQ values in three soil samples representing the background Starina area was 0.66 pg g−1 dw. The predominant contaminants among 2,3,7,8-substituted PCDD/Fs, dl-PCB, and indicator PCBs was OCDD, PCB 118, and PCB 153 respectively. The major contributors to the TEQ were 2,3,4,7,8-PeCDF, PCB 126, 1,2,3,7,8-PeCDD, PCB 156 and 1,2,3,4,7,8-HxCDF + 1,2,3,4,7,9-HxCDF in descending order.  相似文献   
140.
The effect of soil properties on trace element (TE) extraction by the Fish Creek willow cultivar was assessed in a 4-month greenhouse experiment with two contrasted soils and two mycorrhizal treatments (Rhizophagus irregularis and natives). Aboveground tissues represented more than 82 % of the willow biomass and were the major sink for TE. Cadmium and Zn were concentrated in leaves, while As, Cu, Ni, and Pb were mostly found in roots. Willow bioconcentration ratios were below 0.20 for As, Cu, Ni, and Pb and reached 10.0 for Cd and 1.97 for Zn. More significant differences in willow biomass, TE concentrations, and contents were recorded between soil types than between mycorrhizal treatments. A slight significant increase in Cu extraction by willow in symbiosis with Rhizophagus irregularis was observed and was linked to increased shoot biomass. Significant regression models between TE in willow and soil properties were found in leaves (As, Ni), shoots (As, Cd, Cu, Ni), and roots (As, Cu, Pb). Most of the explanation was shared between soil water-soluble TE and fertility variables, indicating that TE phytoextraction is related to soil properties. Managing interactions between TE and major nutrients in soil appeared as a key to improve TE phytoextraction by willows.  相似文献   
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