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1.
We sampled 92 wetlands from four different basins in the United States to quantify observer repeatability in rapid wetland condition assessment using the Delaware Rapid Assessment Protocol (DERAP). In the Inland Bays basin of Delaware, 58 wetland sites were sampled by multiple observers with varying levels of experience (novice to expert) following a thorough training workshop. In the Nanticoke (Delaware/Maryland), Cuyahoga (Ohio), and John Day (Oregon) basins, 34 wetlands were sampled by two expert teams of observers with minimal protocol training. The variance in observer to observer scoring at each site was used to calculate pooled standard deviations (SDpool), coefficients of variation, and signal-to-noise ratios for each survey. The results showed that the experience level of the observer had little impact on the repeatability of the final rapid assessment score. Training, however, had a large impact on observer to observer repeatability. The SDpool in the Inland Bay survey with training (2.2 points out of a 0–30 score) was about half that observed in the other three basins where observers had minimal training (SDpool = 4.2 points). Using the results from the survey with training, we would expect that two sites assessed by different, trained observers who obtain DERAP scores differing by more than 4 points are highly likely to differ in ecological condition, and that sites with scores that differ by 2 or fewer points are within variability that can be attributed to observer differences.  相似文献   

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ABSTRACT

Women’s experiences of drought are often made invisible particularly in terms of their long-term effects. Drought differs from other “natural disasters” in that droughts are, by definition, experienced over an extended time. This means those experiencing drought do so as they age, with elderly cohorts particularly vulnerable. As such, there is a need to better understand the longitudinal needs and experiences of women living with drought. This study investigates the experiences of drought for 15 Australian women aged over 70, over a period of 12 years. Longitudinal qualitative free-text comments written by the oldest cohort of women in the Australian Longitudinal Study on Women’s Health were subject to a thematic analysis. Findings indicate that experiences of drought have a relationship to women’s ability to age in ways they may have hoped. Themes of Work and Physical activity, Connection to place, and, Service access were prominent in women’s comments. These results demonstrate that place is an important aspect in the experience of ageing, that work and physical activity often intensify during drought for elderly people who might otherwise be expecting to retire, and that drought presents particular challenges for older women in terms of access to services. This study highlights the complex interactions of living and ageing in drought for Australian women.  相似文献   

4.
The percentage of the cross-sectional area of two objects (e.g., vehicles, hikers, or animals) that can be seen from each of their locations in a forested area is generally not the same. There is a directionality to the visibility between them. This is due to the relative positions and sizes of the vegetation and other view-blocking features between the objects. An analytical technique has been developed to help understand bidirectional visibility. Its use entails the construction of a visibility diagram containing the basic visibility information between observers in a given setting. An example is presented showing the use of the visibility diagram to determine visibility between two moving observers in a forested environment. The diagram is also used to determine the differences in the percentage each observer has of the other's visible cross-sectional area (bidirectional visibility). A discussion of the application of the technique in the planning or development of new facilities, as well as in forest and wildlife management, is provided.  相似文献   

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Understanding interactions between large ships and large whales is important to estimate risks posed to whales by ships. The coastal waters of Alaska are a summer feeding area for humpback whales (Megaptera novaeangliae) as well as a prominent destination for large cruise ships. Lethal collisions between cruise ships and humpback whales have occurred throughout Alaska, including in Glacier Bay National Park (GBNP). Although the National Park Service (NPS) establishes quotas and operating requirements for cruise ships within GBNP in part to minimize ship–whale collisions, no study has quantified ship–whale interactions in the park or in state waters where ship traffic is unregulated. In 2008 and 2009, an observer was placed on ships during 49 different cruises that included entry into GBNP to record distance and bearing of whales that surfaced within 1 km of the ship’s bow. A relative coordinate system was developed in ArcGIS to model the frequency of whale surface events using kernel density. A total of 514 whale surface events were recorded. Although ship–whale interactions were common within GBNP, whales frequently surfaced in front of the bow in waters immediately adjacent to the park (west Icy Strait) where cruise ship traffic is not regulated by the NPS. When ships transited at speeds >13 knots, whales frequently surfaced closer to the ship’s midline and ship’s bow in contrast to speeds slower than 13 knots. Our findings confirm that ship speed is an effective mitigation measure for protecting whales and should be applied to other areas where ship–whale interactions are common.  相似文献   

6.
This paper examines the viability of the prefabricated detached dwelling, in France, as a home and shelter. It also considers its symbolic nature, and its role both as an investment and a form of inheritance. It is based on an exploratory survey in which 20 householders were interviewed in depth and their comments analysed by means of a specific method of content analysis. Consumer choices are investigated by establishing what prefabrication offers in relation to traditional housing, in terms of the construction process, acquisition procedures, architectural style and cost. Then the author examines ‘inhabiting’ and the feasibility of these houses as an inheritable property with reference to the cultural models of the purpose-built house.It was found that prefabricated housing is a solution suited to all professionally mobile people and to the retired. This adaptation makes home ownership compatible with residential mobility, quite the reverse of what is popularly believed.  相似文献   

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According to recent research findings photographs can be considered valid substitutes for real landscapes in studies on the correlation between observer reactions to a scene and photographs of that scene. These findings are partially supported in the present study. It was found that for some scenes and for some characteristics photographs can form a good substitute for reality: for instance, rather small-scale landscapes can be judged accurately on the characteristics ‘intensity of human use’ and ‘historical character’. For other scenes, such as large-scale landscapes with micro-relief, however, photographs formed a bad substitute.  相似文献   

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This paper explores how residents of Overtown, a low-income neighbourhood in Miami, Florida, view the positive and negative aspects of their neighbourhood “invironment” through photographs taken by residents. The “invironment” [Bell, M., 2004. An invitation to environmental sociology. Thousand Oaks, CA: Pine Forge Press] alludes to the interactions between environment/surroundings and the human body. Residents involved with a community social justice organisation were provided with a photographic workshop and cameras to visually document the positive and negative aspects of their neighbourhood. These participant photographers provided narratives paired with their photographs which were then exhibited at local community events. During the exhibits, community members’ comments on the photographs were recorded. This paper analyses community issues through both photographs and neighbourhood comments inspired by the photographs. The following themes of importance to residents were derived from the photographs and discussion with residents: Housing, Public Space, Neighbourhood Economy, History, Environmental/Invironmental Issues, Human Capital and Power. These themes were all connected by residents’ concerns about inequality in Overtown compared to other neighbourhoods in Miami.  相似文献   

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Abstract: Streamlined sampling procedures must be used to achieve a sufficient sample size with limited resources in studies undertaken to evaluate habitat status and potential management‐related habitat degradation at a regional scale. At the same time, these sampling procedures must achieve sufficient precision to answer science and policy‐relevant questions with an acceptable and statistically quantifiable level of uncertainty. In this paper, we examine precision and sources of error in streambed substrate characterization using data from the Environmental Monitoring and Assessment Program (EMAP) of the U.S. Environmental Protection Agency, which uses a modified “pebble count” method in which particle sizes are visually estimated rather than measured. While the coarse (2?) size classes used in EMAP have little effect on the precision of estimated geometric mean (Dgm) or median (D50) particle diameter, variable classification bias among observers can contribute as much as 0.3?, or about 15‐20%, to the root‐mean‐square error (RMSE) of Dgm or D50 estimates. Dgm and D50 estimates based on EMAP data are nearly equal when fine sediments (<2 mm) are excluded, but otherwise can differ by up to a factor of 2 or more, with Dgm < D50 for gravel‐bed streams. The RMSE of reach‐scale particle size estimates based on visually classified particle count data from EMAP surveys, including variability associated with reoccupying unmarked sample reaches during revisits, is up to five to seven times higher than that reported for traditional measured pebble counts by multiple observers at a plot scale. Nonetheless, a variance partitioning analysis shows that the ratio of among site to revisit variance for several EMAP substrate metrics exceeds 8 for many potential regions of interest, suggesting that the data have adequate precision to be useful in regional assessments of channel morphology, habitat quality, or ecological condition.  相似文献   

10.
This paper compares the role of environmental issues in negotiating Spanish membership of the European Union (EU) with the ongoing enlargement talks with Central and Eastern European countries. The paper first argues that the EU has recognized a need to change the way in which it has traditionally managed environmental issues in enlargement processes. Second, the paper provides evidence of learning processes at the Community level that could have effected a change in Community approaches to enlargement in the environmental field. However, the paper shows that the fundamental principles and procedures applied in preparing for eastern enlargement match those used in previous enlargement rounds, resembling a largely technical exercise with exclusive focus on the applicants' ability to align with the acquis communautaire and the length of transition periods. The lack of sufficient adaptation or reform suggests that path dependence and institutional inertia have constrained the scope for innovations at the level of policy strategy and institutions, for which the shadow of the past has reinforced established patterns of institutional behaviour and practices. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

11.
Despite consensus on the need to adapt to climate change, who should adapt, and how, remain open questions. While local-level actions are essential to adaptation, state and federal governments can play a substantial role in adaptation. In this paper, we investigate local perspectives on state-level flood mitigation policies in Vermont as a means of analysing what leads top-down adaptations to be effective in mobilizing local action. Drawing on interviews with town officials, we delineate local-level perspectives on Vermont's top-down policies and use those perspectives to develop a conceptual framework that presents the ‘fit’ between top-down policies and the local-level context as comprised of three components: Receptivity, Ease of Participation, and Design. We explain how these components and their interactions influence local-level action. This analysis points to how careful consideration of the components of ‘fit’ may lead to greater local-level uptake of top-down adaptation policies.  相似文献   

12.
This paper is aimed to identify the factors that influence peoples' preference for adaptation against the impacts of sea level rise (SLR). A total of 285 respondents from three coastal villages in Bangladesh are randomly interviewed using a semi-structured questionnaire. First, employing the principal component analysis various factors that influence adaptation preferences of people are identified. These factors are related to “demographic and social aspects”, “wealth and economic standing”, “past coping and adaptive behaviour”, “climate knowledge and information” and “spatial aspect” of life. What is common in these factors is their ability to influence peoples' vulnerability. Finally, the binomial logistic regression model is employed to compute the explanatory power of these factors to predict the respondents' preference for adaptation in situ over retreat or vice versa. Model findings are robust for two scenarios of SLR, i.e. 2050–2075 (LR χ 2?=?133.65, pseudo-R 2?=?0.53, p?<?0.001) and 2080–2100 (LR χ 2?=?282.61, pseudo-R 2?=?0.85, p?<?0.001). Therefore, it is concluded that to avoid relocation of substantial number of people initiative for encouraging adaptation in situ must be taken along side establishment of safe shelter, community radio service and campaign for raising climate awareness.  相似文献   

13.
Past research on restorativeness has emphasized mainly the potential of natural environments. In our hypothesis, built environments are also likely to be recognized as restorative places. In this study, focusing on restorative experiences more than on environments alone, attention is drawn on the relative importance of the four restorative components proposed by “attention restoration theory”—being-away, extent, fascination, compatibility—in leisure experiences of people at different stages of the lifespan, and on the characterization of these experiences in terms of relaxation and excitement. We also take account of the time available for restoration and the context in which the need for restoration may emerge, according to three models of the relationships between work and leisure: spill-over, compensation and segmentation. Results show that natural and built environments can have different restorative potentials in relation to the stage of the lifespan and to the time available for restoration; moreover, in people's perception, the four restorative components differ from each other in their relative importance. The social and affective dimensions came out as important features of restorative experiences. Finally, relaxation and excitement in leisure patterns were shown to be differentially related to work characteristics. Briefly, restorativeness emerged as the result of a global “place experience”.  相似文献   

14.
The study deals with the problem of evaluating management strategies for pure stands of Norway spruce (Picea abies Karst) to balance adaptation to and mitigation of climate change, taking into account multiple objectives of a forest owner. A simulation and optimization approach was used to evaluate the management of a 1000 ha model Age-Class forest, representing the age-class distribution of an area of 66,000 ha of pure Norway spruce forests in the Black Forest region of Southwest Germany. Eight silvicultural scenarios comprising five forest conversion schemes which were interpreted as “adaptation” strategies which aims at increasing the proportion of Beech, that is expected to better cope with climate change than the existing Norway spruce, and three conventional strategies including a “Do-nothing” alternative classified as “mitigation”, trying to keep rather higher levels of growing stock of spruce, were simulated using the empirical growth simulator BWINPro-S. A linear programming approach was adapted to simultaneously maximize the net present values of carbon sequestration and timber production subject to the two constraints of wood even flow and partial protection of the oldest (nature protection). The optimized plan, with the global utility of 11,687 €/ha in forty years, allocated a combination of silvicultural scenarios to the entire forest area. Overall, strategies classified as “mitigation” were favored, while strategies falling into the “adaptation”-category were limited to the youngest age-classes in the optimal solution. Carbon sequestration of the “Do-nothing” alternative was between 1.72 and 1.85 million tons higher than the other alternatives for the entire forest area while the differences between the adaptation and mitigation approaches were approximately 133,000 tons. Sensitivity analysis showed that a carbon price of 21 €/t is the threshold at which carbon sequestration is promoted, while an interest rate of above 2% would decrease the amount of carbon.  相似文献   

15.
The Fort Cobb Watershed in Oklahoma has diverse biogeophysical settings and provides an opportunity to explore the association of water quality with a diverse set of landscapes during both wet (April 2007‐December 2009) and dry (January 2005‐March 2007) periods. The objective of this work was to identify spatial patterns in phosphorus (P) (soluble reactive P [SRP] and bioavailable P [BAP]) associated with landscape metrics for two distinct streamflow regimes. Spatial autocorrelation of P was evaluated using contiguous (side‐by‐side) and upstream (upstream:downstream) connectivity matrices. Biogeophysical metrics were compiled for each contributing area, and were partitioned based on association to P concentrations. Results for both SRP and BAP indicated that spatial autocorrelation was present (< 0.05). There was more spatial autocorrelation and stream P concentrations were three to five times higher in the Wet phase than in the Dry phase (< 0.05). Analysis with recursive partitioning resulted in higher R2 with spatial autocorrelation than without spatial autocorrelation and indicated that lateral metrics (topography, soil, geology, management) were better predictors for SRP than instream metrics. During Wet phase, lateral metrics indicative of rapid surface and subsurface water movement were associated with higher P stream concentrations. This research demonstrated that we can detect landscapes more vulnerable to P losses and/or contaminations in either drought or very wet periods.  相似文献   

16.
Before implementing CO2 storage on a large scale its viability regarding injectivity, containment and long-term safety for both humans and environment is crucial. Assessing CO2–rock interactions is an important part of that as these potentially affect physical properties through highly coupled processes. Increased understanding of the physical impact of injected CO2 during recent years including buoyancy driven two-phase flow and convective mixing elucidated potential CO2 pathways and indicated where and when CO2–rock interactions are potentially occurring. Several areas of interactions can be defined: (1) interactions during the injection phase and in the near well environment, (2) long-term reservoir and cap rock interactions, (3) CO2–rock interactions along leakage pathways (well, cap rock and fault), (4) CO2–rock interactions causing potable aquifer contamination as a consequence of leakage, (5) water–rock interactions caused by aquifer contamination through the CO2 induced displacement of brines and finally engineered CO2–rock interactions (6). The driving processes of CO2–rock interactions are discussed as well as their potential impact in terms of changing physical parameters. This includes dissolution of CO2 in brines, acid induced reactions, reactions due to brine concentration, clay desiccation, pure CO2–rock interactions and reactions induced by other gases than CO2. Based on each interaction environment the main aspects that are possibly affecting the safety and/or feasibility of the CO2 storage scheme are reviewed and identified. Then the methodologies for assessing CO2–rock interactions are discussed. High priority research topics include the impact of other gaseous compounds in the CO2 stream on rock and cement materials, the reactivity of dry CO2 in the absence of water, how CO2 induced precipitation reactions affect the pore space evolution and thus the physical properties and the need for the development of coupled flow, geochemical and geomechanical models.  相似文献   

17.
ABSTRACT: Human behavior and response towards storm hazard are examined in this study. One-hundred and twenty flood victims in West Vancouver, British Columbia, were administered a sentence completion test to ascertain how these victims behaved and responded to the flash flood of July 12, 1972. The sentence completion test consisted of 11 sentence stems. Seven of these dealt with the respondent's behavior toward the storm experience, and four with the issue of internal vs. external locus of control. Completions of the seven sentence stems at three time situations showed that West Vancouverites expressed the normal reactions of fear and anxiety before the storm; showed negative emotions during the storm; and displayed a feeling of mutual cooperation after the storm. Completions of the remaining four sentence stems revealed that West Vancouverites emphasized the importance of internal factors, viz., autonomy, drive and hard work, in controlling their lives. They recognized God as a benevolent - protective and almighty - powerful figure. Forty percent of the respondents did not believe in luck, while 8 percent regarded it as important in their lives. One might conclude that West Vancouverites could cope with natural hazardous threats better than those who rely on external factors in directing their lives.  相似文献   

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Previous research has shown that designers' and architects' evaluations of visual stimuli, and of urban and rural environments are not necessarily shared by non-designers and non-architects. Such conclusions may be biased by instrumentation and methodological problems, namely, previous instruments often require verbal responses about stimuli. Hence, non-designers and non-architects may be less capable in expressing themselves, but perceive the same things as the professionals. Another problem stems from professionals who have a narrow range of traits being compared with a general population that has a broader range of traits and therefore has greater within-group variance. This study presents an instrument and a methodology for dealing with these problems in addition to examining the perceptual orientations of architects in comparison to three other professions. Results indicate that architects varied from the other professional groups in their quantitative judgments of the habitats studied but not from all groups in their qualitative judgments. Hence, architects may be a distinct professional culture for some design variables only.  相似文献   

20.
Please send me your comments and questions on TQEM. Address it to me: TQEM Questions & Answers Editor, 22 West 21st Street, New York, NY 10010. I will credit you with the question and send out an extra copy of TQEM. My thanks to James, Jack, and Sheila for sharing in the quality revolution this issue.  相似文献   

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