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101.
The measurement of place attachment: Personal,community, and environmental connections 总被引:3,自引:0,他引:3
Place attachment has been researched extensively in the social and behavioural sciences over the past two decades. However, it is challenging for researchers to assimilate the mixed messages presented in the place attachment literature and to understand the multiple place attachment terms. In this study, a four-dimensional model of rural landholder attachments to their natural resource management region was conceptually and empirically developed with the aim of developing an integrated approach to the measurement of place attachment that clearly distinguishes between different elements of place scholarship. A 29-item place attachment scale with the dimensions of place identity, place dependence, nature bonding, and social bonding was tested on a random sample of rural landholders in the Adelaide and Mount Lofty Ranges in South Australia (N = 320). The majority of respondents were male (69.3%) and the average age was 59 years. The scale was reduced to 20-items and then administered simultaneously and in the same response format to rural landholders in two other areas of South Australia: the Northern and Yorke region (N = 664) and South Australian Murray-Darling Basin region (N = 659). In both studies, the majority of respondents were male (85%) and the average age was 55 years. Exploratory factor and reliability analyses of Adelaide and Mount Lofty Ranges and Northern and Yorke datasets produced a five-dimensional model of place attachment with high reliabilities. Social bonding divided into the constructs of family bonding and friend bonding. The refined five-dimensional model was then examined for convergent validity, with moderate but significant correlations found between individual attachment constructs and dependent variables expected to be related to the construct, such as place identity and length of residence, and nature bonding and time currently spent in nature. We used confirmatory factor analysis to test the goodness-of-fit of the South Australian Murray-Darling Basin (SAMDB) dataset to the proposed five-dimensional model and then compared its fit to the traditional two-dimensional model of place identity and place dependence. The five-dimensional model provided moderate fit for the SAMDB data. We conclude with a discussion of the validity and reliability of the five-dimensional model and its future role in place attachment research. 相似文献
102.
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104.
Wölz J Engwall M Maletz S Olsman Takner H van Bavel B Kammann U Klempt M Weber R Braunbeck T Hollert H 《Environmental science and pollution research international》2008,15(7):536-553
Background, aim, and scope
As a consequence of flood events, runoff and remobilized sediments may cause an increase of ecotoxicologically relevant effects from contaminant reservoirs. Aquatic and terrestrial organisms as well as cattle and areas of settlement are exposed to dislocated contaminants during and after flood events. In this study, the impacts of two flood events triggered by intense rain at the rivers Neckar and Rhine (Southern Germany) were studied. Effects in correlation to flood flow were assessed at the river Neckar using samples collected at frequent intervals. River Rhine suspended particulate matter (SPM) was sampled over a longer period at normal flow and during a flood event. Three cell lines (H4L1.1c4, GPC.2D.Luc, RTL-W1) were used to compare Ah receptor agonist activity in different biotest systems. Multilayer fractionation was performed to identify causative compounds, focusing on persistent organic contaminants. 相似文献105.
Field Validation of a Conservation Network on the Eastern Shore of Maryland,USA, Using Breeding Birds as Bio-Indicators 总被引:1,自引:0,他引:1
Maryland’s Green Infrastructure (GI) is a network of large, intact natural areas (hubs), interconnected by linear swaths of
riparian or upland vegetation (corridors). The GI serves significant ecological functions and provides the bulk of the state’s
natural support system. This study examined whether the GI as mapped does, in fact, identify Maryland’s most ecologically
valuable forested lands, using forest interior dwelling birds (hereafter called “forest birds”) as bio-indicators. We conducted
bird point counts within forest both inside and outside of hubs on Maryland’s Eastern Shore. We also collected a wide variety
of habitat data. We found that both the condition of a forest and its surrounding landscape influenced the bird communities.
On average, forest bird richness was significantly higher within hubs; furthermore, almost all sites with at least five forest
bird species present were in hubs. Forest bird richness and abundance were highest in undisturbed, mature broadleaf forest
with wetlands and streams nearby. We detected a significant relationship between forest bird richness and the ecological score
of a finer-scale landscape assessment, focused on “cells” of about 0.1 ha in size. This field study also validated the Rapid
Field Assessment (RFA) protocol developed in 2001 to assess, on the ground, the relative condition of individual sites or
properties within the GI. Forest bird richness and abundance were positively correlated with the RFA community scores. Our
results underscore the importance of maintaining regional biological diversity by retaining large blocks of forest, especially
mature forest containing streams and wetlands. 相似文献
106.
Passive vapor monitoring of underground storage tanks (USTs) containing volatile hydrocarbons at locations external to the tank (an external system) is touted as a fast and effective method of leak detection. However, major gaps remain in our knowledge of the physical processes that relate a measured vapor concentration to the leak rate, thus making network design according to a quantitative design criterion nearly impossible, and differentiation between surface spills and a leaking UST requires certain levels of sophistication in the leak detection system and in the analysis that are not usually available. Heavier-than-air vapors from the constituents of stored hydrocarbons could result in a density-driven convective propagation component that complicates the design of leak detection systems, and finally, detection times are highly sensitive to concentration detection threshold levels set by the system. The use of inadequate systems and analyses can lead to either wasted efforts or excessive subsurface contamination. This paper discusses the physical processes involved, explores the above aspects of external passive vapor leak detection design, and suggests some alternatives as they pertain to gasoline service stations. 相似文献
107.
Tsakovski S Puxbaum H Simeonov V Kalina M Löffler H Heimburger G Biebl P Weber A Damm A 《Journal of environmental monitoring : JEM》2000,2(5):424-431
The aim of the present study was to analyse the data structure of a large data set from rainwater samples collected during a long-term interval (1990-1997) by the Austrian Precipitation Monitoring Network. Eleven sampling sites from the network were chosen as data sources (chemical concentrations of major ions only) covering various location characteristics (height above sea level, rural and urban sampling positions, Alpine rim and Alpine valley disposition, etc.). The analytical results were treated by the application of already classical environmetric approaches, such as linear regression analysis, time-series analysis and principal components analysis (PCA). For most of the sampling sites, a distinct trend of acidity decrease of the wet precipitation was observed. An overall decrease in sulfate concentration for the whole period and all sites of 3.9% year(-1) (2.0 muequiv. L(-1) year(-1)) was found. The free acidity decrease for most of the sites was between 3.5 and 10.9% year(-1). No significant linear trends were found for nitrate. Base cations either decreased (mean percentage decrease for calcium was 5.4% year(-1) and for magnesium 4.4% year(-1)) or did not show any significant change (sodium, potassium). The overall decrease in ammonium concentration was 2.3% year(-1). Further, some typical "rural" (summer minima and winter maxima) and "urban" (winter minima and spring maxima) seasonal behaviour for the majority of the sites in consideration could be defined, indicating the influence of local emission sources. Several latent factors, named "anthropogenic", "crustal" and "mixed salt", were revealed by the multivariate modelling procedure (PCA) possessing a similar structure for most of the sites. The unavoidable exceptions observed were indications of the influence of sporadic local events (construction and agricultural activities, secondary emission sources, etc.), and an effort was made to explain these exceptions. 相似文献
108.
H. H. Weber 《Die Naturwissenschaften》1955,42(10):270-275
109.
Average radial growth rates of the hemispherical aragonite colonies deposited by the Indo-Pacific scleractinian reef coral Platygyra spp. were determined by measuring the thickness of density variations in the skeleton that are revealed by X-radiography. Ninety-one specimens from 21 localities were examined, but only 54 of these exhibited well-defined growth-banding. The apparent temperature dependence of growth rate is linear over the range 23.9° to 29.3°C, averaging 5.4±0.94 mm/year at 24°C, 8.0±0.42 mm/year at 27°C, and 9.7 ±0.58 mm/year at 29°C (90% confidence limits). Expression of the influence of temperature on growth rate in terms of the Arrhenius equation yields an activation energy of 20,680 cal/mole, which is comparable to values for typical biological reactions, but is only half that reported for skeletogenesis in another reef coral, Pocillopora damicornis, on the basis of controlled incubation studies involving 45Ca uptake. 相似文献
110.
Some coelenterates of the class Hydrozoa and some anthozoan coelenterates from the subclass Octocorallia secrete skeletons of calcium carbonate. Skeletal carbonates of three hydrozoans and of two octocorals were analyzed for the stable isotopes of carbon and oxygen. The results suggest that each of these coelenterates deposits CaCO3 in oxygen isotopic equilibrium with seawater, and that at least one octocoral, Heliopora, has skeletal carbon in apparent isotopic equilibrium with atmospheric CO2. Two of these coelenterates, Millepora and Helipora, are significant contributors to the construction of coral reefs. Whereas 18O of these corals is temperature dependent, 13C is not obviously related to temperature. The 18O-temperature relationship is not significantly different from the oxygen isotope paleotemperature scale developed by Epstein et al. (1953). These findings contrast with numerous analyses of the carbonate in scleractinian coelenterates, which have long been reported to deposit CaCO3 skeletons whose carbon and oxygen isotopic compositions are not in equilibrium with the external sea-water environment. 相似文献