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261.
Rachele S. Wilson Kerry Jones Sean Fleischfresser Bridgette Davis Genevieve Jones 《社会与自然资源》2018,31(3):335-350
This article examines roles, opportunities, and challenges for Indigenous land management in rapidly developing landscapes through a case study of Bunya Bunya Country Aboriginal Corporation, a not-for-profit organization on the Sunshine Coast, Queensland, Australia. An analysis of data collected through semistructured interviews, participant observation, and analysis of secondary sources reveals that Aboriginal land managers work in a variety of roles to manage issues affecting the local environment and cultural heritage sites. These efforts are challenged by the absence of Native Title and colonial land management policies, which restrict Aboriginal involvement in land management. We conclude that there is a need for alternative pathways to engage with Aboriginal land managers who cannot, or choose not to, proceed with Native Title. Decolonized decision-making tools and sustainable enterprises are viable opportunities that partially address these challenges and could deliver tangible socio-economic and cultural benefits to local Aboriginal and non-Aboriginal people. 相似文献
262.
Harvey Karen L. Jones Harrison P. Schrijver Carolus J. Penn Matthew J. 《Solar physics》1999,190(1-2):35-44
Simultaneous measurements of the magnetic fields in the photosphere and chromosphere were used to investigate if magnetic
flux is submerging at sites between adjacent opposite polarity magnetic network elements in which the flux is observed to
decrease or `cancel'. These data were compared with chromospheric and coronal intensity images to establish the timing of
the emission structures associated with these magnetic structures as a function of height. We found that most of the cancelation
sites show either that the bipole is observed longer in the photosphere than in the chromosphere and corona (44%) or that
the timing difference of the disappearance of the bipole between these levels of the atmosphere is unresolved. The magnetic
axis lengths of the structures associated with the cancelation sites are on average slightly smaller in the chromosphere than
the photosphere. These observations suggest that magnetic flux is retracting below the surface for most, if not all, of the
cancelation sites studied. 相似文献
263.
K.R. Briffa P.D. Jones R.B. Vogel F.H. Schweingruber M.G.L. Baillie S.G. Shiyatov E.A. Vaganov 《Climatic change》1999,43(1):151-168
We present a selective review of tree-ring variability and inferred climate changes in Europe during the 16th century. The dendroclimatological evidence is assessed within the context of the last 500 years and some interpretational problems are discussed. The tree-ring evidence is compared with various non-dendroclimatic evidence. The body of evidence shows that a large region of mid and northern Europe experienced a sharp cooling at around 1570/80 that, at least in the north, marked a shift towards a prolonged period of cool conditions. This region had its southern boundary in the Alps and there is little evidence for a major cooling in southern Europe. 相似文献
264.
Evaluation of the North Atlantic Oscillation as simulated by a coupled climate model 总被引:12,自引:1,他引:11
T. J. Osborn K. R. Briffa S. F. B. Tett P. D. Jones R. M. Trigo 《Climate Dynamics》1999,15(9):685-702
The realism of the Hadley Centre’s coupled climate model (HadCM2) is evaluated in terms of its simulation of the winter North
Atlantic Oscillation (NAO), a major natural mode of the Northern Hemisphere atmosphere that is currently the subject of considerable
scientific interest. During 1400 y of a control integration with present-day radiative forcing levels, HadCM2 exhibits a realistic
NAO associated with spatial patterns of sea level pressure, synoptic activity, temperature and precipitation anomalies that
are very similar to those observed. Spatially, the main model deficiency is that the simulated NAO has a teleconnection with
the North Pacific that is stronger than observed. In a temporal sense the simulation is compatible with the observations if
the recent observed trend (from low values in the 1960s to high values in the early 1990s) in the winter NAO index (the pressure
difference between Gibraltar and Iceland) is ignored. This recent trend is, however, outside the range of variability simulated
by the control integration of HadCM2, implying that either the model is deficient or that external forcing is responsible
for the variation. It is shown, by analysing two ensembles, each of four HadCM2 integrations that were forced with historic
and possible future changes in greenhouse gas and sulphate aerosol concentrations, that a small part of the recent observed
variation may be a result of anthropogenic forcing. If so, then the HadCM2 experiments indicate that the anthropogenic effect
should reverse early next century, weakening the winter pressure gradient between Gibraltar and Iceland. Even combining this
anthropogenic forcing and internal variability cannot explain all of the recent observed variations, indicating either some
model deficiency or that some other external forcing is partly responsible.
Received: 20 August 1998 / Accepted: 12 May 1999 相似文献
265.
266.
Synthesis of Environmental Impacts of Deep Seabed Mining 总被引:1,自引:0,他引:1
267.
A single Upper Carboniferous fluvio-deltaic cycle (Namurian, R2b5) in the south part of the Pennine Basin of northern England has been reinterpreted using a sequence stratigraphic approach. In upward succession the deposits comprise basinal mudstones, localized thick density current deposits, delta slope deposits and delta-top sandstones, followed abruptly by basinal mudstones. Earlier interpretations linked these elements with a single, mainly regressive, cycle, referred to as a turbidite-fronted delta. Recent evidence for strong glacio-eustatic sea-level fluctuations in the Namurian suggests that it is unlikely that the previous simple model can explain the spatial arrangement of all the lithological units. This paper attempts to identify elements of the Exxon sequence stratigraphic model, in which changes of sea level are an essential part. The basinal mudstones represent deep-water deposition and imply a highstand of sea level. Thick density current deposits are now known to be localized close to the basinward limit of delta progradation, so cannot be seen as a ubiquitous component of the depositional system. They may form a detached fan, or a fan located at the foot of the delta slope. Slope siltstones include turbidite-like sandstones, but these are interbedded with tractional sandstones and Pelecypodichnus trace fossils, giving no clear indication of water depth. The delta-top sandstones, some coarse and pebbly, can in places be shown to consist of two parts separated by a significant erosion surface now regarded as a type 1 sequence boundary. The erosion surface is locally incised about 80 m into the delta deposits, forming a major palaeovalley. Giant cross-beds (foresets 20 m thick) forming part of the palaeovalley fill are restricted to the basinward end of this feature. A curve of relative sea level inferred for the R2b5 interval suggests a fourth-order cycle in which two sharp rises are separated by a gradual fall. Possible minor (fifth-order) rises and falls may be superimposed. © 1997 John Wiley & Sons, Ltd. 相似文献
268.
269.
270.
Matthew J. Genge Luke Alesbrook Natasha V. Almeida Helena C. Bates Phil A. Bland Mark R. Boyd Mark J. Burchell Gareth S. Collins Luke T. Cornwell Luke Daly Hadrien A. R. Devillepoix Matthias van Ginneken Ansgar Greshake Daniel Hallatt Christopher Hamann Lutz Hecht Laura E. Jenkins Diane Johnson Rosie Jones Ashley J. King Haithem Mansour Sarah McMullan Jennifer T. Mitchell Gavyn Rollinson Sara S. Russell Christian Schröder Natasha R. Stephen Martin D. Suttle Jon D. Tandy Patrick Trimby Eleanor K. Sansom Vassilia Spathis Francesca M. Willcocks Penelope J. Wozniakiewicz 《Meteoritics & planetary science》2024,59(5):948-972
Fusion crusts form during the atmospheric entry heating of meteorites and preserve a record of the conditions that occurred during deceleration in the atmosphere. The fusion crust of the Winchcombe meteorite closely resembles that of other stony meteorites, and in particular CM2 chondrites, since it is dominated by olivine phenocrysts set in a glassy mesostasis with magnetite, and is highly vesicular. Dehydration cracks are unusually abundant in Winchcombe. Failure of this weak layer is an additional ablation mechanism to produce large numbers of particles during deceleration, consistent with the observation of pulses of plasma in videos of the Winchcombe fireball. Calving events might provide an observable phenomenon related to meteorites that are particularly susceptible to dehydration. Oscillatory zoning is observed within olivine phenocrysts in the fusion crust, in contrast to other meteorites, perhaps owing to temperature fluctuations resulting from calving events. Magnetite monolayers are found in the crust, and have also not been previously reported, and form discontinuous strata. These features grade into magnetite rims formed on the external surface of the crust and suggest the trapping of surface magnetite by collapse of melt. Magnetite monolayers may be a feature of meteorites that undergo significant degassing. Silicate warts with dendritic textures were observed and are suggested to be droplets ablated from another stone in the shower. They, therefore, represent the first evidence for intershower transfer of ablation materials and are consistent with the other evidence in the Winchcombe meteorite for unusually intense gas loss and ablation, despite its low entry velocity. 相似文献