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71.
Council Approaches to Implementing Sustainability: a case of rearranging deck chairs on the Titanic?
Carmel M. Dunn 《The Australian geographer》2010,41(3):351-366
Local government has a key role to play in implementing sustainability. Yet even councils attempting to address the issue of sustainability are often unacceptably slow and ineffective in their endeavours. This study investigates the approaches that councils currently take in implementing sustainability, as this may shed additional light on the slow progress of councils towards sustainability. The approaches of three New South Wales councils were examined and assessed using a model developed for the study that utilised the Ecological Footprint as the primary assessment tool. The model assessed three key aspects of council approaches to implementing sustainability: (1) the issues councils target for change; (2) the methods councils use to change behaviours; and (3) the clarity and holistic nature of their approaches. All three council approaches scored poorly against the model mainly as a result of the councils' failure to target the behaviours of their residents that are causing the greatest ecological harm. The major implication is that councils need to reconsider, and possibly overhaul, their approaches to implementing sustainability as these approaches are unlikely ever to achieve sustainability. 相似文献
72.
Matthew R. Dunn 《新西兰海洋与淡水研究杂志》2013,47(5):1103-1113
The diet of the squid Nototodarus sloanii was determined from examination of stomach contents of 388 specimens of 14.3–41.0 cm dorsal mantle length sampled at depths of 211–760 m on the Chatham Rise, New Zealand. Prey items were predominantly mesopelagic fishes, with some crustaceans and cephalopods. The most important prey species identified was Maurolicus australis, followed by Lampanyctodes hectoris, and unidentified squids (Teuthoidea). Multivariate analyses using distance‐based linear models, non‐parametric multi‐dimensional scaling, analysis of similarities, and similarity percentages, indicated crustaceans were more important in the diet of smaller squid (83–480 g), the fish component of the diet was dominated by L. hectoris on the east Chatham Rise and M. australis on the west Chatham Rise, and there may be a difference in diet with sex, with crustaceans and cephalopods more important for females. The results indicated that N. sloanii, similar to other ommastrephid squids, foraged primarily in the mesopelagic layers. 相似文献
73.
There is a large sociological literature on racial- class-, and economically- based segregation in the United States and there is some evidence that residential segregation by income may have deleterious health consequences for residents of large U.S. cities. The health consequences of segregation in Canadian metropolitan areas, however, remain unknown and the comparison with the U.S. is always compelling. In this paper, we investigate the hypothesis that residential segregation by income may be associated with mortality in Canadian and U.S. metropolitan areas. Given the strong relationship between individual level socioeconomic status and health, it follows that metropolitan areas which isolate individuals economically could produce conditions that severely limit the life chances and therefore the health chances of the most vulnerable. To investigate the association between residential segregation by income and population health, we examined the relationship between working-age mortality and Jargowsky's (1996) neighbourhood sorting index (NSI) for a large group of North American metropolitan areas. We found a relationship between increased segregation and increased mortality for U.S. metropolitan areas but no such relationship for Canadian metropolitan areas. We also determined that income segregation could not be considered in isolation from income inequality – that, in effect, income inequality provides the propensity for meaningful segregation to occur. We further demonstrated the importance of considering both income inequality and income segregation together, especially when the analysis is intended to compare metropolitan areas. We conclude with a discussion of the need for an improved measure of segregation to better reflect the theoretical arguments for the relationship between concentration of poverty and affluence and population health. 相似文献
74.
75.
The distance between two points on opposite sides of the San Andreas Fault is being derived from laser tracking of near-earth satellites as part of an experiment to estimate the motion along the plate boundary. The two sites, at Otay Mountain near San Diego and at Quincy in northern California, are nearly 900 km apart and approximately 150 and 270 km, respectively, away from the main strike of the San Andreas Fault. The angle between the fault and the intersite vector is approximately 25°. In the fall of 1972 satellite laser tracking systems occupied these two sites, and from the data collected the relative location of the two sites was determined. The two sites were reoccupied in the fall of 1974 and again in the fall of 1976, and provided two further estimates of the relative positions of the two sites.The results of these first three measurements indicate a shortening of the intersite baseline between San Diego and Quincy at an average rate of 9 ± 3 cm/year, suggesting a much larger possible present-day motion across the fault system than expected. The main source of error in this analysis is the motion of the spacecraft which is significantly affected by unmodeled anomalies in the earth's gravity field. However, major advances in our knowledge of the gravity field are expected over the next few years and as these occur the accuracy of the present results will improve. 相似文献
76.
Peter Dunn 《Journal of Geodesy》1981,55(2):143-158
When the orbit of the Landsat I spacecraft was liberated to natural forces, the loss of observations to the remote sensing
community was balanced by a modest gain for geodesy. The orbit’s long ground-track repeat period of eighteen days gives rise
to a shallow resonance with fourteenth, twenty-eighth and forty-second order terms in the geopotential. A single continuous
span of twenty-four days of Unified S-Band tracking data, collected at a single station in 1976, has been analyzed to define
constraints on the dominant resonance terms of these orders and of fourteenth-order fringe resonance effects depending on
the eccentricitye≈.002. Tracking observations from other stations collected during 1974 and 1975 gave essentially the same results, which provided
error estimates for the lumped resonance coefficients. The application of the resonance model can considerably improve the
definition and prediction of the Landsat 1 orbit. Direct numerical estimates of the influence coefficients in the resonance
constraint equations were made to confirm the accuracy of analytical expressions which allow the equations to be applied to
geopotential fields of arbitrarily high degree and order. Several recently derived gravity fields were tested against the
Landsat resonance constraints and their comparative agreement is discussed. 相似文献
77.
Summary Is it possible to make appropriate use of GIS for 'development' (here defined as change desirable for the poor) in countries where human and financial resources may be limited? We argue that it is, and should be taught, but that there are no quick fixes. 相似文献
78.
All platinum-group metals (PGM) in ashed plant tissues, from an area of platinum mineralization in Saskatchewan, have been measured by neutron activation analysis of a NiS fire assay bead. Concentrations of up to 1350 ppb (ng/g) Pd, 880 ppb Pt, 49 ppb Rh, 37 ppb Ru, 24 ppb Ir, and 15 ppb Os occur in ashed twigs of black spruce (Picea mariana), indicating that the ratios of PGM uptake are about the same as those occurring in the bedrock. Plants growing on drift-covered diabase, known to have about 100 ppb PGM, contain up to 77 ppb Pt in ash, demonstrating the potential value of biogeochemical methods in helping to delineate platiniferous zones. Twigs of black spruce, jack pine, and labrador tea appear to be the optimum sample media in this environment.A rapid multi-element neutron activation analysis by direct irradiation of tissue permits measurement of 0.05 ppb Ir in dry material, or 2 ppb Ir in ashed samples. In view of the normally very low concentrations of Ir in plants, any detectable Ir probably indicates enrichment of PGM in the substrate.Comparison of several wet-chemical analytical methods indicates that the optimum (cost-effective) technique for detecting 1–2 ppb Pt, Pd, or Rh in 2-g samples of ash is by Te co-precipitation (following fusion and dissolution), and analysis by ICP-MS with sample introduction by electrothermal vaporization. However, care must be taken to ensure complete dissolution of all PGMs in the ash. 相似文献
79.
A stochastic model of particle dispersion in the atmosphere 总被引:2,自引:0,他引:2
Stochastic models of turbulent atmospheric dispersion treat either the particle displacement or particle velocity as a continuous time Markov process. An analysis of these processes using stochastic differential equation theory shows that previous particle displacement models have not correctly simulated cases in which the diffusivity is a function of vertical position. A properly formulated Markov displacement model which includes a time-dependent settling velocity, deposition and a method to simulate boundary conditions in which the flux is proportional to the concentration is presented. An estimator to calculate the mean concentration from the particle positions is also introduced. In addition, we demonstrate that for constant coefficients both the velocity and displacement models describe the same random process, but on two different time scales. The stochastic model was verified by comparison with analytical solutions of the atmospheric dispersion problem. The Monte Carlo results are in close agreement with these solutions.This work partially performed at Sandia National Laboratories supported by the U.S. Department of Energy under contract number DE-AC04-76DP00789. 相似文献
80.
Graphical diagnostics for logistic oil exploration models 总被引:1,自引:0,他引:1
This paper demonstrates how some recently developed graphical diagnostic techniques can be used to explore and improve the specification of logistic oil exploration models. Techniques are applied to information on 124 hydrocarbon exploration wells drilled between 1948 and 1963 into the B Division of the Mississippian (Osage Series) in a 13 by 13 square mile area of Stafford County, south-central Kansas. 相似文献