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851.
A unique collaborative, sociological study undertaken during 1995-7, explored the social construction of drought as a disaster, looking at farm families in two Australian states: Queensland (beef producers) and New South Wales (sheep/wheat producers). A decision was made to interview the women and men separately to test our hypothesis that there would be gender issues in any analysis of a disaster, but particularly one which has had so much long-term impact on individuals, families and communities, such as drought. Interviews were conducted with over 100 individuals male and female. We conclude that drought as a disaster is a gendered experience. The paper draws on the narratives of some women involved in the study to identify 'themes of difference' which confirm the necessity to maintain gender as a variable in all studies of the social impacts of disaster. 相似文献
852.
Asbestos cement (AC) pipes were commonly installed in the drinking water distribution systems from the mid 1920s to the late 1980s. In recent years, an increase in the number of water main breaks has occurred in the AC portions of some pipe networks, which can be partially attributed to the corrosion of the aged pipes. This study evaluated the potential role that microorganisms may have played in the degeneration and failure of AC pipes. In this study, a fresh AC pipe section was collected from the distribution network of the City of Regina, Canada and examined for microbiological activities and growth on inside surfaces of pipe sample. Black slime bacterial growths were found to be attached to inner pipe surfaces and a distinctively fibrous internal coating (patina) with iron oxides was formed over the time. The microbial populations inside the patina and the black slime were tested with BART(tm) testers. Heterotrophic aerobic bacteria (HAB) and slime forming bacteria (SLYM) dominated in both the black growths and inside the patina. Iron related bacteria, denitrification bacteria and sulfate reducing bacteria were also commonly present. Microbial challenge assays were conducted by submerging the cut segments of the AC pipe into selected bacterial cultures for a period of 10 days under both aerobic and anaerobic environments. Weight changes were determined and the surface morphology was examined for each of the assayed pipe segments. Results indicated that acid producing bacteria, SLYM and HAB could facilitate the pipe weight loss under anaerobic environments. 相似文献
853.
Sonia Akter Roy Brouwer Saria Choudhury Salina Aziz 《Mitigation and Adaptation Strategies for Global Change》2009,14(3):215-229
The study aims to assess the commercial viability of a potential crop insurance market in Bangladesh. In a large scale household
survey, agricultural farm households were asked for their preferences for a hypothetical crop insurance scheme using double
bounded (DB) contingent valuation (CV) method. Both revenue and production cost based indemnity payment approaches were applied
to assess the commercial viability of a crop insurance program assuming a partner-agent (PA) model of insurance supply. Crop
insurance is found marginally commercially viable in riverine flood plain areas. The expected indemnity payable consistently
exceeds the expected insurance premium receivable by the insurer for the households living in wetland basin and coastal floodplain.
We conclude that a uniform structure of crop insurance market does not exist in Bangladesh. The nature of the disaster risks
faced by the farm households and the socio-economic characteristics of the rural farm communities need to be taken into careful
consideration while designing such an insurance scheme.
相似文献
Sonia AkterEmail: |
854.
Since the announcement by Fleischmann and Pons that the excess enthalpy generated in the negatively polarized Pd–D-D2O system was attributable to nuclear reactions occurring inside the Pd lattice, there have been reports of other manifestations
of nuclear activities in this system. In particular, there have been reports of tritium and helium-4 production; emission
of energetic particles, gamma or X-rays, and neutrons; as well as the transmutation of elements. In this communication, the
results of Pd–D co-deposition experiments conducted with the cathode in close contact with CR-39, a solid-state nuclear etch
detector, are reported. Among the solitary tracks due to individual energetic particles, triple tracks are observed. Microscopic
examination of the bottom of the triple track pit shows that the three lobes of the track are splitting apart from a center
point. The presence of three α-particle tracks outgoing from a single point is diagnostic of the 12C(n,n′)3α carbon breakup reaction and suggests that DT reactions that produce ≥9.6 MeV neutrons are occurring inside the Pd
lattice. To our knowledge, this is the first report of the production of energetic (≥9.6 MeV) neutrons in the Pd–D system.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
855.
Johanna J. Vollenweider Ron A. Heintz Lawrence Schaufler Robert Bradshaw 《Marine Biology》2011,158(2):413-427
Quantifying the nutritional quality of forage fish is integral for understanding upper trophic levels as forage fish are the
dominant prey for top predator fish, marine mammals, and sea birds. Many existing reports documenting body composition of
forage species are not comparable due to confounding effects. This study systematically assessed the variability in proximate
composition and energy content of 16 forage species in southeastern Alaska (57.2626 N/133.7394 W) between 2001 and 2004. Variation
in energy and lipid contents was related to habitat, epipelagic planktivores varying most, mesopelagics intermediate, and
demersal species relatively invariable. Season was the greatest source of variation as a result of short growing seasons at
high latitude and energy allocation strategies for reproduction and growth. Among species that varied seasonally, energy and
lipid increased over summer and declined during winter. Annual differences in body composition occurred during periods of
peak energy content. Sampling recommendations and guidance for bioenergetics models are provided. 相似文献
856.
Srivastava R Roy BK 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(5):629-634
The isolation procedure of the seed proteins of Amaranthus blitum have been analyzed at different pH conditions. Qualitative studies were carried out by using electrophoretic technique sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Mainly four protein fractions i.e. albumin, globulin, prolamin and glutelin were obtained. Protein isolates were prepared by (a) extraction at different alkaline pH (9, 10, 11 and 12) and precipitation atpH 5 and (b) extraction at pH 9 and precipitation atdifferentpH (4, 5, 6 and 7). The composition of isolates, prepared by method (a), depended on extraction pH. The isolate extracted at pH 8 was mainly composed of albumin and globulin, whereas at pH 9, 10 and 11 showed the presence of prolamin and glutelin. Electrophoretic pattern of different isolates had five major bands with molecular weight of 30, 45, 72, 84 and 90 kDt respectively. The increase of the extraction pH led to the increase in protein yield. With method (b) isolates obtained were variable in composition. At pH 7 albumin and prolamine were present, whereas at pH 4, 5 and 6 all 4 protein fractions were precipitated. According to the quantitative estimation of the albumin, globulin, prolamin and glutelin in the seed flour the contents were 26.4, 25, 5.81 and 42.7%, respectively. The results suggest that composition of protein isolates could be controlled by different extraction and precipitation pH. 相似文献
857.
The northern Great Plains of Saskatchewan is one of the most significantly modified landscapes in Canada. While the majority of anthropogenic disturbances to Saskatchewan’s grasslands are the result of agricultural practices, development of petroleum and natural gas (PNG) resources is of increasing concern for grassland conservation. Although PNG developments require formal assessment and regulatory approval, follow-up and monitoring of the effects of PNG development on grasslands is not common practice. Consequently, the effects of PNG activity on grasslands and the spatial and temporal extent of such impacts are largely unknown. This paper examines the spatial and temporal extent of PNG development infrastructure from 1955 to 2006 in a grassland ecosystem in southwest Saskatchewan. The effects of PNG development on grassland ecology were assessed from measurements of ground cover characteristics, soil properties, and plant community composition at 31sites in the study area. PNG lease sites were found to have low cover of herbaceous plants, club moss (Lycopodiaceae), litter, and shallow organic (Ah) horizons. Lease sites were also characterized by low diversity of desirable grassland plants and low range health values compared to off-lease reference sites. These impacts were amplified at active and highly productive lease sites. Impacts of PNG development persisted for more than 50 years following well site construction, and extended outward 20 m–25 m beyond the direct physical footprint of PNG well infrastructure. These results have significant implications with regard to the current state of monitoring and follow-up of PNG development, and the cumulative effective of PNG activity on grassland ecosystems over space and time. 相似文献
858.
Henriette?I.?JagerEmail author Mark?S.?Bevelhimer Roy?L.?King Katy?A.?Smith 《Environmental management》2011,48(4):795-807
Military landscapes represent a mixture of undisturbed natural ecosystems, developed areas, and lands that support different
types and intensities of military training. Research to understand water-quality influences of military landscapes usually
involves intensive sampling in a few watersheds. In this study, we developed a survey design of accessible headwater watersheds
intended to improve our ability to distinguish land–water relationships in general, and training influences, in particular,
on Fort Stewart, GA. We sampled and analyzed water from watershed outlets. We successfully developed correlative models for
total suspended solids (TSS), total nitrogen (TN), organic carbon (OC), and organic nitrogen (ON), which dominated in this
blackwater ecosystem. TSS tended to be greater in samples after rainfall and during the growing season, and models that included
%Wetland suggested a “build-and-flush” relationship. We also detected a positive association between TSS and tank-training, which
suggests a need to intercept sediment-laden runoff from training areas. Models for OC showed a negative association with %Grassland. TN and ON both showed negative associations with %Grassland, %Wetland, and %Forest. Unexpected positive associations were observed between OC and equipment-training activity and between ON and %Bare ground + Roads. Future studies that combine our survey-based approach with more intensive monitoring of the timing and intensity of training
would be needed to better understand the mechanisms for these empirical relationships involving military training. Looking
beyond local effects on Fort Stewart streams, we explore questions about how exports of OC and nitrogen from coastal military
installations ultimately influence estuaries downstream. 相似文献
859.
After nearly a century of height suppression, willows (Salix spp.) in the northern range of Yellowstone National Park, U.S.A., are increasing in height growth as a possible consequence of wolf (Canis lupus) restoration, climate change, or other factors. Regardless of the drivers, the recent release of this rare but important habitat type could have significant implications for associated songbirds that are exhibiting declines in the region. Our objective was to evaluate bird response to releasing willows by comparing willow structure and bird community composition across three willow growth conditions: height suppressed, recently released, and previously tall (i.e., tall prior to the height increase of released willows). Released and previously tall willows exhibited high and similar vertical structure, but released willows were significantly lower in horizontal structure. Suppressed willows were significantly shorter and lower in horizontal cover than released or previously tall willows. Bird richness increased along a gradient from lowest in suppressed to highest in previously tall willows, but abundance and diversity were similar between released and previously tall willows, despite lower horizontal cover in the released condition. Common Yellowthroat (Geothlypis trichas) and Lincoln's Sparrow (Melospiza lincolnii) were found in all three growth conditions; however, Yellow Warbler (Dendroica petechia), Warbling Vireo (Vireo gilvus), Willow Flycatcher (Empidonax traillii), and Song Sparrow (Melospiza melodii) were present in released and previously tall willows only. Wilson's Warbler (Wilsonia pusilla) was found in previously tall willows only, appearing to specialize on tall, dense willows. The results of our a priori habitat models indicated that foliage height diversity was the primary driver of bird richness, abundance, and diversity. These results indicate that vertical structure was a more important driver of bird community variables than horizontal structure and that riparian and willow-dependent bird species have responded positively to increased willow growth in the region. 相似文献
860.
Mackechnie C Maskell L Norton L Roy D 《Journal of environmental monitoring : JEM》2011,13(10):2687-2691
Environmental monitoring is essential for assessing the current state of the environment, measuring impacts of environmental pressures and providing evidence to government. Recent UK government announcements have indicated an increased role for 'Big Society' in monitoring. In this paper, we review available literature concerning the use of citizen science for monitoring, present examples of successful volunteer monitoring work and highlight important issues surrounding the use of volunteers. We argue that in order to ensure that environmental monitoring continues to be effective it is important to learn from examples where volunteers are currently used, acknowledging constraints and identifying potential approaches which will help to maximise both their engagement and data quality. Effective partnerships between environmental monitoring organisations and volunteers may thus aid the UK in developing robust coordinated monitoring systems that will be less vulnerable to funding variances. 相似文献