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71.
72.
The Kimberley coast in Australia's far north-west is the traditional country and home of a number of Indigenous groups and hosts some of the country's richest cultural heritage, most spectacular rock art, scenery and wildlife, making it an attractive tourism destination. A growing expedition cruise industry provides the main means of visitor access to remote coastal sites and offers excursions to shore-based attractions in what are mostly Aboriginal Reserve lands. In light of concerns about environmental and cultural site impacts resulting from increasing visitor numbers, this study examined biophysical site impacts along access trails to shore-based attractions and used qualitative methods to ascertain cultural impacts. The synthesis of the findings highlights that cultural concerns arising from visitor access without having sought traditional owner consent for such access, combined with a lack of traditional owner involvement in the planning, management or running of visitor activities, overshadow currently low environmental impacts of onshore expedition cruise activities. To overcome the continuing impasse regarding the issue of unsanctioned visitor access, the Kimberley urgently needs a coordinated approach by key stakeholders and the traditional owners which recognises and acknowledges the historical context. Such a process would facilitate tourism activities to become culturally sustainable.  相似文献   
73.
Ultraviolet disk-integrated solar phase curves of the icy galilean satellites Europa, Ganymede, and Callisto are presented, using combined data sets from the International Ultraviolet Explorer (IUE), Hubble Space Telescope (HST), and the Galileo Ultraviolet Spectrometer. Global, disk-integrated solar phase curves for all three satellites, in addition to disk-integrated solar phase curves for Europa's leading, trailing, jovian, and anti-jovian hemispheres, are modeled using Hapke's equations for 7 broadband UV wavelengths between 260 and 320 nm. The sparse coverage in solar phase angle, particularly for Ganymede and Callisto, and the noise in the data sets poorly constrain some of the photometric parameter values in the model. However, the results are sufficient for forming a preliminary relationship between the effects of particle bombardment on icy surfaces and photometric scattering properties at ultraviolet wavelengths. Callisto exhibits a large UV opposition surge and a surface comprised of relatively low-backward scattering particles. Europa's surface displays a dichotomy between the jovian and anti-jovian hemispheres (the anti-jovian hemisphere is more backward scattering), while a less pronounced hemispherical variation was detected between the leading and trailing hemispheres. Europa's surface, with the exception of the trailing hemisphere region, appears to have become less backscattering between the late-1970s-early-1980s and the mid-1990s. These results are commensurate with the bombardment history of these surfaces by magnetospheric charged particles.  相似文献   
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Spectra of asteroid 4 Vesta obtained in October 1990 with the International Ultraviolet Explorer are reanalyzed and reinterpreted. A large portion of the eastern hemisphere (based on the prime meridian definition of Thomas et al., 1997a) is darker at UV wavelengths than much of the western hemisphere. The UV lightcurve is in contrast with the visible lightcurve, which shows that the eastern hemisphere is brighter than the western. These IUE spectra of Vesta thus may be evidence for the “spectral reversal,” first seen on the Moon by Apollo 17, where the visibly brighter lunar highlands are darker than the maria at far-UV wavelengths. This effect was linked to space weathering when it was noted (Wagner et al., 1987) that the spectral reversal appears in the laboratory spectra of lunar soils but not powdered lunar rocks.We investigate Vesta’s UV lightcurve and spectral reversal, and its possible connection with space weathering. The addition to grain coatings of small amounts of submicroscopic iron (SMFe) through vapor deposition causes drastic spectral changes at UV-visible wavelengths (Hapke, 2001), while the longer wavelength spectrum remains largely unaffected. Other laboratory results (e.g., Hiroi and Pieters, 1998) indicate that the UV-visible wavelength range is affected by simulated weathering processes in a manner similar to what is seen on Vesta. It is likely that Vesta has experienced relatively minor amounts of space weathering, as indicated by the spectral reversal, along with the subtle visible-near infrared weathering effects (e.g., Binzel et al., 1997).  相似文献   
76.
We present a far ultraviolet (FUV) spectrum of Saturn’s moon Enceladus from the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST). We have put upper limits on emission from C, N, and O lines in Enceladus’ atmosphere and column densities for the C lines assuming solar resonance scattering. We find these upper limits to be relatively low—on the order of tens to thousands of Rayleighs and with C column densities on the order of 108–1015 cm?2, depending on the assumed source size. We also present a segment of a reflectance spectrum in the FUV from ~1900–2130 Å. This region was sensitive to the different ice mixtures in the model spectra reported by Hendrix et al. (Hendrix, A.R., Hansen, C.J., Holsclaw, G.M. [2010]. Icarus, 206, 608). We find the spectrum brightens quickly longward of ~1900 Å, constraining the absorption band observed by Hendrix et al. from ~170 to 190 nm. We find our data is consistent with the suggestion of Hendrix et al. of the presence of ammonia ice (or ammonia hydrate) to darken that region, and also possibly tholins to darken the mid-UV, as reported by Verbiscer et al. (Verbiscer, A.J., French, R.G., McGhee, C.A. [2005]. Icarus, 173, 66).  相似文献   
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Development and societal changes in the twentieth century have transformed the nature of fishing in Fiji. This paper attempts to consolidate a large amount of decentralized work on the development of Fijian fisheries to address the long-term sustainability and economic viability of Fiji's marine resources. Taking a broad perspective, this paper provides an overview that connects the historic context of Fiji's fisheries development with economic policy to address overfishing. The analysis highlights the need for an overarching management approach that encompasses the integration of Fiji's offshore and inshore fisheries to ensure the achievement of long-term economic benefits.  相似文献   
79.
The Greenhouse Gas Inventory for the United Kingdom currently uses a simple carbon-flow model, CFLOW, to calculate the emissions and removals associated with forest planting since 1920. Here, we aim to determine whether a more complex process-based model, the BASic FORest (BASFOR) simulator, could be used instead of CFLOW. The use of a more complex approach allows spatial heterogeneity in soils and weather to be accounted for, but places extra demands on uncertainty quantification. We show how Bayesian methods can be used to address this problem.  相似文献   
80.
South Africa has a high prevalence of non-communicable diseases (NCDs) compared to other African countries. Government has predicted that NCDs will be a major threat of health in the country in the next 20–30 years and recommended a significant reduction in NCDs. This research studies spatial patterns of deaths resulting from chronic lower respiratory diseases (CLRD), malignant neoplasms of digestive organs (MNDO), diabetes mellitus (DM) and cerebrovascular diseases (CVD) among adults aged 15–69 years in 2011 at municipality level. The study uses secondary data from the civil registration system; population census; and supplementary information from the Business Register and a database of public health facilities. Moran’s Index, hot spot analysis and geographically weighted regression were applied to measure spatial autocorrelation of age-standardised death rates; to identify municipalities of high risk of deaths due to selected NCDs; and associated socio-economic and demographic factors. Clusters of high risk of deaths from selected NCDs were identified, with those for CLRD and MNDO mainly in the urban municipalities around the mid and western parts of the country while for DM and CVD they occurred mostly in the urban and rural north-eastern part, as well as in the urban municipalities of Northern Cape for CVD. Hot spots showed differential socio-economic and demographic risk factors in NCDs, which included sex, urbanisation, density of public hospitals; death occurrence in health facilities; smoking; asbestos roofing; mining and quarrying businesses. Findings highlight the importance of community-specific interventions and the need for a neighbourhood-based approach in tackling NCDs.  相似文献   
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