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261.
Fail-to-hatch kestrel (Falco tinnunculus) eggs collected at the end of the 1999 and 2005 breeding seasons from nest boxes in and around the city of Rome, Italy, were analyzed by gas chromatography with electron capture detection for their PCB content and for the presence of DDT derivatives and other organochlorines. Among the various PCBs, congeners 153 and 180 were detected in all the eggs and showed the highest concentrations. Eggs collected from the same nest from a polluted location in Rome during 2 different years showed similar type and number of PCB congeners. These data and the fact that eggs from another nest near a sulphate mine had, atypically, low-chlorinated congeners support the conclusion that eggs of this species, whose adults in the Mediterranean and continental Europe perform only short or no migration movements, might be indicative of local pollution. When multiple eggs in the same clutch were analyzed, the PCBs were similar in type but their concentration decreased within clutch, likely in parallel to the laying order. 相似文献
262.
Natural disasters are inevitably the outcome of cultural agonisms. The cultural politics of natural disasters are shaped by competing claims and conceptions of ‘nature’. Recent disasters in Indonesia are directly linked to these contending conceptions and the ways in which different social groups imagine risk and reward. The Sidoarjo volcanic mudflow of 2006 represents a volatile and violent exemplar of contending cultural and economic claims. Like other disasters in Indonesia and elsewhere in the developing world, this ‘natural’ disaster is characterised by differing conceptions of ‘nature’ as cultural tradition, divine force, and natural resource. A new extractive project in East Java is exhibiting similar economic and cultural agonisms, particularly around the notion of development, environment, self‐determination, and tradition. This paper examines the ‘disputes over meaning’ associated with natural disasters in contemporary societies, and the ways in which they are related to human culture, social organisation, and hierarchical systems of violence. 相似文献
263.
T. J. Wright V. W. Greene H. J. Paulus 《Journal of the Air & Waste Management Association (1995)》2013,63(5):337-341
The microbial population (types and numbers) of a vertical profile of air in an industrial area of the Twin Cities was determined between May and November 1967. No consistent relationships could be shown to exist between the microbial contamination and the meteorological parameters concurrently measured. The mean viable counts ranged from 58/ft3 at grade level to 22/ft3 at 500 ft. Regardless of altitude, molds constituted approximately 70% of the total airborne microflora, bacteria between 19 and 26%, and yeasts and actinomycetes the remainder. The particle size with which the viable population was associated showed a consistent peak in the 3 – 5 μ range. 相似文献
264.
Robert S. Wright Richard M. Kamens Joseph E. Sickles II Harvey E. Jeffries W. Cary Eaton 《Journal of the Air & Waste Management Association (1995)》2013,63(3):248-250
Solid growth is seen for the air pollution control industry for the rest of the century. Over the next twelve years purchases of particulate control equipment in the U.S. will grow at a rate considerably better than the GNP; growth rates in developing countries will be even higher. The portion of air pollution control expenditures represented by FGD systems is predicted to rise from its current level of 12 percent to 62 percent in 1991 if acid rain legislation is passed as predicted. A significant market is seen also for municipal, industrial and agricultural waste incinerators. Geography plays an important role in the strength of the industry; in the future, industrialized countries will be the sites of new designs and applications, while developing countries will be the life extension of the tried and proven designs. Industrywide, new product development is seen as an underused route to success. 相似文献
265.
Robert S. Wright Emery J. Kong Mark A. Bahner C. Andrew Clayton Carlos M. Nuñez Geddes H. Ramsey 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1110-1115
ABSTRACT Research Triangle Institute and the U.S. Environmental Protection Agency conducted several projects to measure hydrocarbon emissions associated with the manufacture of fiberglass-reinforced plastics. The purpose of these projects was to evaluate pollution prevention techniques to reduce emissions by altering raw materials, application equipment, and operator technique. Analytical techniques were developed to reduce the cost of these emission measurements. Emissions from a small test mold in a temporary total enclosure (TTE) correlated with emissions from full-size production molds in a separate TTE. Gravimetric mass balance measurements inside the TTE generally agreed to within ± 30 % with total hydrocarbon (THC) measurements in the TTE exhaust duct. Pure styrene evaporation tests served as quality control checks for THC measurements and generally agreed to within ± 5 %. 相似文献
266.
Decades of acid deposition have caused acidification of lakes in Sweden. Here we use data for 3000 lakes to run the acidification model MAGIC and estimate historical and future acidification. The results indicate that beginning in about 1920 a progressively larger number of lakes in Sweden fell into the category of “not naturally acidified” (∆pH > 0.4). The peak in acidification was reached about 1985; since then many lakes have recovered in response to lower levels of acid deposition. Further recovery from acidification will occur by the year 2030 given implementation of agreed legislation for emissions of sulphur (S) and nitrogen (N) in Europe. But the number of catchments with soils being depleted in base cations will increase slightly. MAGIC-reconstructed history of acidification of lakes in Sweden agrees well with information on fish populations. Future acidification of Swedish lakes can be influenced by climate change as well as changes in forest harvest practices. 相似文献
267.
268.
Cocheo C Sacco P Ballesta PP Donato E Garcia S Gerboles M Gombert D McManus B Patier RF Roth C de Saeger E Wright E 《Journal of environmental monitoring : JEM》2008,10(8):941-950
The need to collect data representative of overall urban pollution is all-important in order to monitor the population exposure. High spatial resolution monitoring using diffusive samplers allows studying of the urban pollutant distribution, thus enabling deeper investigation of their generation and diffusion mechanisms. Nevertheless, such a monitoring campaign has a certain cost. In this study we point out how to find the best compromise between the number of necessary measurements and the affordable costs for monitoring campaigns. We also describe an innovative method for the proper design of a fixed urban monitoring network by means of preliminary high spatial resolution campaigns using diffusive samplers. Four European capital cities (Dublin, Madrid, Paris and Rome) were monitored six times, each time for seven days. Benzene, toluene, ethylbenzene, xylenes (BTEX) and NO(2) concentrations were measured at 146 sites in Dublin, 293 in Madrid, 339 in Paris and 290 in Rome. Multiscale grids have been drawn which ranged in mesh size from 500 m to 2 km. The statistical processing of data produced a twofold result: the creation of isoconcentration maps with geostatistical procedures, and an algorithm aimed at locating the minimum number of sampling sites where the fixed monitoring stations should be placed. Average urban levels estimated on the basis of these selected sites differ by less than 8% from those calculated on the whole populations of the sampled points. The aim of this work is to investigate how far the resolution of a monitoring campaign of urban pollution by diffusive sampling can be reduced, thus making the monitoring less expensive in terms of human and financial resources, while preserving the same quality of the results that could be achieved with a higher resolution. We found that there is no significant loss of information when the resolution of the monitoring grid for BTEX is lowered to a mesh size of 1.85 km, that is a sampling site each 3.4 km(2), and that the minimum number of sampling sites to be used is N = 0.29 A, where A is the urban surface to be monitored (in km(2)). As the spatial distribution of NO(2) is less sensitive to the distance from the emission source than that of BTEX, this relationship could be retained as a valid lower limit for the mesh grid size also for NO(2) monitoring. 相似文献
269.
We used random amplified polymorphic DNA (RAPDs) to examine small-scale spatial genetic structure in the red alga Delisea pulchra (Greville) Montagne at two locations near Sydney, Australia. We examined genetic structure among plants at four spatial scales
ranging from 2 km apart down to <50 cm apart between locations, among sites within locations, among quadrats within sites,
and among plants within quadrats. Haploid stages of D. pulchra were absent from the populations studied, suggesting that they are maintained through asexual reproduction of diploid plants.
Consistent with this, we found that 19 RAPD phenotypes scored in this study had multiple individuals, indicating the presence
of clones in these populations. However, there were no RAPD phenotypes common to two locations separated by only 2 km. Analysis
of molecular variance revealed that strong genetic differences occurred between plants from these two locations, with 46.3%
of the total genetic variation occurring at this scale, most probably reflecting limited gene flow. Within each location,
<25% of the genetic variation was attributable to differences among sites or quadrats, indicating gene flow at those smaller
scales. Most of the variation within each location occurred at the smallest spatial scale, among plants within 0.25 m2 quadrats. Nonetheless, some pairwise genetic distances (φST) between sites or quadrats within locations were large, indicating some genetic divergence on smaller scales. Genetic distance
was independent of spatial distance within both locations, suggesting that fine-scale differences within locations were most
probably caused by variation in fine-scale patterns of water movement or fine-scale natural selection. We assessed the impact
of one potential selective agent, grazing sea urchins, on the fine-scale genetic structure of D. pulchra. There was no evidence that grazing by sea urchins affected the genetic structure of D. pulchra. In combination with demographic data, our results indicated that local populations of D. pulchra within locations were relatively open and that fine-scale genetic structure was probably constrained by gene flow. At the
larger scale however, strong genetic differentiation indicated little gene flow between locations and restricted dispersal
of spores.
Received: 22 April 1999 / Accepted: 29 November 1999 相似文献
270.
Edwin Sabuhoro Brett A. Wright Robert B. Powell Jeffrey C. Hallo Patricia A. Layton Ian E. Munanura 《Environmental management》2020,65(3):410-419
Illegal activities and use of park resources are the main challenges facing mountain gorilla (Gorilla beringei beringei) conservation and the protection of their habitats in the East Africa’s Greater Virunga Transboundary Landscape (GVTL). Indigenous residents around GVTL are considered the primary illegal users of park resources. Despite this, there is limited understanding of the current and past perceptions of indigenous residents living in communities adjacent to two GVTL parks; Volcanoes National Park in Rwanda and Mgahinga Gorilla National Park in Uganda. Equally, there is also limited understanding regarding the actual incidences of illegal activities inside both parks. This paper addresses these gaps. Perception data were collected from indigenous residents living adjacent to both parks. Further, Ranger-based Monitoring (RbM) data from both parks were analyzed to determine actual numbers and types of illegal activities over the 9-year period. Interestingly, findings indicated that residents perceived the prevalence of illegal activities to be decreasing across GVTL. To the contrary, RbM findings indicated that the number of actual illegal activities was increasing significantly, particularly in Volcanoes National Park. The discrepancy found between the two perspectives provides for a discussion of the social biases potentially present in these data, and their implications for management. Results also illuminated the subsistence-related nature of most illegal behaviors and suggest that to reduce illegal activities and local dependency on park resources, park management must work with communities and support them in tapping into alternative livelihoods and finding ways to address community household subsistence needs. 相似文献