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41.
Characterizing Small Subbasins: A Case Study from Coastal Oregon 总被引:1,自引:0,他引:1
A fine-grained statisticaly robust probability sample of stream segments is used to compare two small (20,000 hectare) subbasins of the Tillamook watershed, north coastal Oregon. The two subbasins are matched with respect to several variables [size coastal climates], but vary in terms of geology and consequently land use. A total of 67 wadeable + non-wadeable sizes were identified for sampling in the two subbasins (combined) over two field seasons from a sampling universe consisting of the River Reach File 3 (blue lines on 1:100,000 maps). Target variables include an extensive array of physical habitat endpoints, selected water chemistry endpoints, species composition, and relative abundance of both benthic macroinvertebrates and fish. Field protocols generally followed those of the U.S. EPA's Environmental Monitoring and Assessment Program (EMAP).Eleven fish species were encountered, a typically low number for coastal Oregon streams. Exploratory analysis using nonmetric multidimensional scaling revealed that 92.4% of the variation in the fish assemblages could be explained with two ordination axes. Environmental factors related to stream size and substate were the most correlated to these axes. Further, stream segments for the two subbasins tended to map in different areas of species space. Therefore, we also give unweighted probability distributions for several of the factors that heavily on these two axes by subbasins, as well as probability distributions for chemical endpoints. Results from the subset of sites sampled during the first year (21 wadeable sites) reveal: 1) differences between samples from the two subbasins relates to dream size and substrate composition that are consistent with known differences in geology and land use, 2) unexpectedly minor differences between samples from the two subbasins for stream temperature, canopy cover, and dissolved oxygen, 3) differences between samples from the two subbasins for total P, and total N, possibly related to land use, and 4) unexpected differences in samples from the two subbasins for conductivity, probably related to geological factors. Sample size for each subbasin is low and therefore our samples cannot be taken to necessarily characterize either subbasin. However, our findings are consistent with a comprehensive assessment that had been previously produced for one of the two subbasins.All field work was completed in 8 weeks 3-person field crew. We conclude that rapid assessment protocols, based on probability samples at this level of resolution, can be a cost-effective approach to watershed analysis. This approach should be seen as a complement to, rather than a replacement for, systematic surveys that produced finer scale, reach specific information on factors such as channel complexity and cover relevant to in-stream restoration planning. 相似文献
42.
Michael J. Ford 《Conservation biology》2002,16(3):815-825
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Mrs J. A. Bell J. Pearn G. Cohen J. Ford J. Halliday N. Martin M. Mulcahy S. Purvis-Smith G. Sutherland 《黑龙江环境通报》1985,5(1):53-58
This paper reports the results of a complete national survey to measure utilization rates of prenatal cytogenetic diagnosis (P.C.D.) in women of advanced maternal age in Australia. P.C.D. has been available throughout Australia for the last decade. Every laboratory in Australia providing a P.C.D. service for the years 1979–1982 took part in this study. Utilization rates (both National and State rates) by ages of mothers, are presented. Big interstate differences exist. The 1982 National P.C.D. utilization rate for pregnant women who were 40 years of age and over was 38.8 per cent, and this rate has shown an average annual increase of 9 per cent. In those four States which offered P.C.D. to pregnant women of 35 years or over the median utilization rate was 20 per cent. These Australian rates indicate an under-utilization of P.C.D. services with (in 1982) 50–80 per cent of ‘at risk’ women not being tested. Factors which influence this are discussed. 相似文献
46.
Vulnerability of Inuit food systems to food insecurity as a consequence of climate change: a case study from Igloolik, Nunavut 总被引:1,自引:0,他引:1
James D. Ford 《Regional Environmental Change》2009,9(2):83-100
This paper develops a conceptual model to examine the vulnerability of Inuit food systems to food insecurity as a consequence
of climate change. The model illustrates that food system vulnerability is determined by the exposure and sensitivity of the
food system to climate-related risks and its adaptive capacity to deal with those risks. The model is empirically applied
using a case study from Igloolik, Nunavut. Specifically, the paper focuses on how extreme climate-related conditions in 2006
interacted with the food system to affect food security, using 2006 as a lens to identify and characterize some of the processes
and conditions shaping vulnerability, and establishing a baseline for identifying and characterizing processes that are likely
to shape future vulnerability. There is a high level of adaptive capacity among Igloolik Inuit, with food sharing mechanisms,
hunting flexibility, and store-food access moderating the impact of climatic-risks on food security. However, high fuel and
commodity prices, the increasing economic burden of adapting to back-to-back years with unfavorable climatic conditions, underlying
community vulnerabilities, and the nature to the climate extremes in 2006, overwhelmed the adaptive capacity of many community
members. Those dependent on traditional foods and having limited access to financial resources were particularly vulnerable. 相似文献
47.
Founded on the assumption that communicator style is situationally and contextually influenced, this study investigates the effects of job-related stress on communicator style. It was specifically designed to measure the effects of job-related stress factors on employee communicator style within the context of a medical center organization. Three central research questions are posed: (1) what, if any, meaningful differences in communicator style can be found from general work conditions to stress-specific conditions; (2) do different stress conditions give rise to meaningful differences in communicator style; (3) what communicator style differences exist among three major medical center employee hierarchies in response to stress-specific situations. The results indicate that communicator style in the stress-specific sample was significantly more dominant, open, attentive but less dramatic and friendly. Multivariate analysis revealed that communicator style accounted for the greatest differences between employees who were experiencing stress due to being unprepared to perform their work role. All role-related stress variables were more powerfully discriminated by the communicator style variables than department/unit stress (stress at the work group level). Finally, communicator style variables provided statistically significant discrimination of three occupational groups: physicians, administrators/managers, and line employees. Physicians appeared to be more assertive and less supportive in their communication; administrators/managers were assertive but also supportive while line employees were both submissive and supportive in their communicator style. These three employee groups were also discriminated using the job-related stress variables. Although statistically significant findings were obtained, the discriminant functions were less powerful than the communicator style discriminant functions. 相似文献
48.
ABSTRACT: The accurate and reliable determination of floodplains, floodway boundaries, and flood water elevations are integral requirements of Flood Insurance Studies. These studies are intended to be used for determining the flood insurance rates. Therefore, the accuracy of the water surface profiles are important. To ensure the high degree of accuracy, the HUD Flood Insurance Administration has developed standards which must be met in the analysis of water surface profiles. A somewhat less accurate study is required for the preparation of Flood Emergency Plans. As part of the flood insurance studies of eight locations in the State of North Dakota, various flood hazard and floodplain information reports were reviewed. The hydrologic and hydraulic analyses, especially the computation of the 100-year water surface profiles, were completed using both simplified and complex hydraulic computation methods. Significant differences were found (1 to 3 feet) between the profiles computed by the SCS simplified method and those computed by HEC-2 computer program. However, the floodplain boundaries determined by both methods were found to be similar. Approximate methods are recommended for rapid determination of the floodplain, floodway boundaries, and inundation area mapping, while sophisticated computer programs (HEC-2) are recommended to be used for developing areas where the 100-year flood elevation has a significant impact on the cost of land development. 相似文献
49.
Perceptions of climate change risks in primary resource use industries: a survey of the Canadian mining sector 总被引:2,自引:0,他引:2
James D. Ford Tristan Pearce Jason Prno Frank Duerden Lea Berrang Ford Maude Beaumier Tanya Smith 《Regional Environmental Change》2010,10(1):65-81
A survey documenting how climate change is perceived, experienced, and responded to in the Canadian mining sector was administered
to industry practitioners at the Prospectors & Developers Association of Canada annual meeting. Nine key findings from the
survey are discussed: (1) The Canadian mining sector is sensitive to climate-related conditions. (2) Climate change is perceived
to be having a negative impact on mining operations. (3) Companies are taking action to manage the current impacts. (4) Cost
and uncertainty are commonly identified barriers to adapting to current climate change. (5) Future climate change is expected
to have impacts for the industry. (6) Climate change projections are perceived as threats by the majority of respondents.
(7) Despite the perceived threat, companies are not currently taking action to plan for future impacts. (8) Cost and uncertainty
are commonly identified barriers to adapting to future climate change impacts. (9) The mining sector is currently making efforts
to reduce greenhouse gas emissions. The survey is exploratory in nature, establishing a baseline for targeted research to
assess in greater detail the vulnerability of mining to climate change. 相似文献
50.
Ford CI Walter M Northcott GL Di HJ Cameron KC Trower T 《Journal of environmental quality》2007,36(6):1599-1608
This study was conducted to improve the pentachlorophenol (PCP) bioremediation ability of white-rot fungi in highly contaminated field soils by manipulating bioaugmentation variables. These were the dry weight percentage of fungal inoculum addition (31-175 g kg(-1)), PCP concentration (100-2137 mg kg(-1) PCP), fungal inoculum formulation, and time (1-7 wk). Five fungal isolates were used: the New Zealand isolates Trametes versicolor (L.: Fr.) HR131 and Trametes sp. HR577; the North American isolates Phanerochaete chrysosporium Burds. (two isolates) and Phanerochaete sordida (Karst.) Erikss. & Ryv. Pentachlorophenol removal, manganese peroxidase, and laccase activity, and the formation of chloroanisoles in the contaminated field soils were measured. The majority of PCP removed by the Trametes isolates was in the first week after bioaugmentation. The maximum PCP removal by the fungi varied from 50 to 65% from a 1065 mg kg(-1) PCP contaminated field soil. Pentachlorophenol was preferentially converted to pentachloroanisole (PCA) by the Phanerochaete isolates (>60%), while 2 to 9% of the PCP removed by two Trametes isolates was converted to PCA. A pH increase was measured following bioaugmentation that was dependent on PCP concentration, fungal inoculum addition, and formulation. This, together with rapid initial PCP removal, possibly changed the bioavailability of the remaining PCP to the fungi and significantly decreased the sequestering of PCP in the contaminated field soils. The research supports the conclusion that New Zealand Trametes spp. can rapidly remove PCP in contaminated field soils. Bioavailability and extractability of PCP in the contaminated field soil may significantly increase after bioaugmentation. 相似文献