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1.
Regions and sustainable development: regional planning matters 总被引:1,自引:0,他引:1
This paper looks at how the term 'sustainable development' has been used in the process of regional plan making over the past decade. It emphasizes the differing geographies of these debates within England, in terms of how sustainable development has been used to justify different types of approach in different parts of the country. Both drawing on and challenging recent work on state theory, the paper argues the need to see regional planning as a part of a multi-scalar governance system, whose importance should not be underestimated. 相似文献
2.
Sea-level rise is likely to cause significant changes in the morphodynamic state of beaches in the higher latitudes, resulting in steeper beaches with larger particle sizes. These physical changes have implications for beach invertebrate communities, which are determined largely by sediment particle size, and hence for ecosystem function. Previous studies have explored the relationships between invertebrate communities and environmental variables such as particle size, beach slope and exposure to wave action, and often these physical variables can be integrated in various indices of morphodynamic state. Most of these studies incorporated a full range of beach types that included wave-dominated surf beaches, where the wave action is harsh enough to enable reliable estimates of breaker height, a parameter included in several of the indices, and concluded that more dissipative beaches with gentler slopes and finer particle sizes often support a higher number of species and greater abundance than more reflective beaches. Whether these predictions remain valid for less wave-dominated beaches, where breaker height is more difficult to determine, is uncertain. In the present study, the abundance of meio- and macrofauna was quantified across a range of beaches in the UK, which are generally towards the lower energy end of the morphodynamic gradient, and their relationships with beach physical properties explored. No significant relationships were found between abundance and the standard morphodynamic indices, but significant relationships were found for both macro- and meiofaunal abundance when these indices were combined with an exposure index (derived from velocity, direction, duration and the effective fetch). All the relationships identified between abundance and combined morphodynamic indices indicated a higher abundance of both macro- and meiofauna on the more dissipative beaches. The reverse was however found for species richness. If predictions that accelerated sea-level rise will move beaches towards a more reflective morphodynamic state are correct, this could lead to declines in the abundance of meio- and macrofauna, with potential adverse consequences for ecosystem functioning. 相似文献
3.
Dave Lazarus 《Mathematical Geology》1994,26(7):817-832
Marine micropaleontology must in the future provide more precise chronologic and paleoenvironmental information, which in turn must be based on better, more consistent taxonomic and distributional data. Better tools for synthesis and standardization of this data are needed, as the ever expanding published literature is rapidly becoming unmanageable by purely manual compilation methods. The micropaleontology group at the ETH has developed a large relational database of marine microfossil data to partially meet this need. It currently contains biogeographic data on the distribution in Deep Sea Drilling Project (DSDP) and Ocean Drilling Program (ODP) holes of nearly 8,000 species of Cenozoic planktonic foraminifera, radiolaria, diatoms and calcareous nannofossils. The database also includes full stratigraphic occurrence (range chart) data for these fossil groups from more than 100 selected Neogene holes. A particular feature of the database is that all sample information and species names in the original reports are linked to newly created, updatable, comprehensive age models and synonymy lists which reflect modern chronology and taxonomic usage. Searches of the database automatically make use of this information in producing reports. Species ' occurrences, including first and last occurrence information, can be further analyzed using external spreadsheet and statistics packages; plotted by mapping programs; or displayed by a new program which creates composite age-range charts. 相似文献
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6.
Gold mineralisation in the White River area, 80 km south of the highly productive Klondike alluvial goldfield, is hosted in
amphibolite facies gneisses in the same Permian metamorphic pile as the basement for the Klondike goldfield. Hydrothermal
fluid which introduced the gold was controlled by fracture systems associated with middle Cretaceous to early Tertiary extensional
faults. Gold deposition occurred where highly fractured and chemically reactive rocks allowed intense water–rock interaction
and hydrothermal alteration, with only minor development of quartz veins. Felsic gneisses were sericitised with recrystallisation
of hematite and minor arsenic mobility, and extensively pyritised zones contain gold and minor arsenic (ca 10 ppm). Graphitic
quartzites (up to 5 wt.% carbon) caused chemical reduction of mineralising fluids, with associated recrystallisation of metamorphic
minerals (graphite, pyrrhotite, pyrite, chalcopyrite) in host rocks and veins, and introduction of arsenic (up to 1 wt.%)
to form arsenopyrite in veins and disseminated through host rock. Veins have little or no hydrothermal quartz, and up to 19 wt.%
carbon as graphite. Late-stage oxidation of arsenopyrite in some graphitic veins has formed pharmacosiderite. Gold is closely
associated with disseminated and vein sulphides in these two rock types, with grades of up to 3 ppm on the metre scale. Other
rock types in the White River basement rocks, including biotite gneiss, hornblende gneiss, pyroxenite, and serpentinite, have
not developed through-going fracture systems because of their individual mineralogical and rheological characteristics, and
hence have been little hydrothermally altered themselves, have little hydrothermal gold, and have restricted flow of fluids
through the rock mass. Some small post-metamorphic quartz veins (metre scale) have been intensely fractured and contain abundant
gold on fractures (up to 40 ppm), but these are volumetrically minor. The style of gold mineralisation in the White River
area is younger than, and distinctly different from, that of the Klondike area. Some of the mineralised zones in the White
River area resemble, mineralogically and geochemically, nearby coeval igneous-hosted gold deposits, but this resemblance is
superficial only. The White River mineralisation is an entirely new style of Yukon gold deposit, in which host rocks control
the mineralogy and geochemistry of disseminated gold, without quartz veins. 相似文献
7.
The UK is committed to meeting a series of ‘high-level marine objectives’ which are required to satisfy national obligations and to meet international commitments for the marine environment. There are more than 16 such international high-level policy driven obligations and commitments, together with more than 18 European and more than 12 of national origin. In the UK, there is an assumption that the current and planned monitoring will provide evidence to demonstrate achievement against these high-level objectives. 相似文献
8.
Anna Zacharioudaki Shunqi Pan Dave Simmonds Vanesa Magar Dominic E. Reeve 《Ocean Dynamics》2011,61(6):807-827
In this paper, we investigate changes in the wave climate of the west-European shelf seas under global warming scenarios.
In particular, climate change wind fields corresponding to the present (control) time-slice 1961–2000 and the future (scenario)
time-slice 2061–2100 are used to drive a wave generation model to produce equivalent control and scenario wave climate. Yearly
and seasonal statistics of the scenario wave climates are compared individually to the corresponding control wave climate
to identify relative changes of statistical significance between present and future extreme and prevailing wave heights. Using
global, regional and linked global–regional wind forcing over a set of nested computational domains, this paper further demonstrates
the sensitivity of the results to the resolution and coverage of the forcing. It suggests that the use of combined forcing
from linked global and regional climate models of typical resolution and coverage is a good option for the investigation of
relative wave changes in the region of interest of this study. Coarse resolution global forcing alone leads to very similar
results over regions that are highly exposed to the Atlantic Ocean. In contrast, fine resolution regional forcing alone is
shown to be insufficient for exploring wave climate changes over the western European waters because of its limited coverage.
Results obtained with the combined global–regional wind forcing showed some consistency between scenarios. In general, it
was shown that mean and extreme wave heights will increase in the future only in winter and only in the southwest of UK and
west of France, north of about 44–45° N. Otherwise, wave heights are projected to decrease, especially in summer. Nevertheless,
this decrease is dominated by local wind waves whilst swell is found to increase. Only in spring do both swell and local wind
waves decrease in average height. 相似文献
9.
We present a case study of the organizational framework of the Gulf of Mexico Alliance (GOMA), which was implemented to promote the use of ecosystem-based management (EBM) at a regional level. GOMA is a state-led initiative formed to protect and restore coastal and marine resources of the Gulf of Mexico. Representatives of the US Gulf States, together with their federal partners, clearly defined ecological, social, and economic short- and long-term objectives to be reached through regional collaborations. The aim of this paper is to show how GOMA, and particularly the Ecosystem Integration and Assessment Priority Issue Team, in its attempt to apply ecosystem approaches to manage marine resources, modified the common organizational scheme by implementing partnerships at various governmental (federal, state, local) and nongovernmental levels. We address the following major points considered to be of importance for EBM implementation: (1) multilevel cooperation, (2) stakeholders’ involvement, (3) sharing of information, (4) bridging science and policy, and (5) consensus-based decision making. 相似文献
10.
We consider the scenario in which the presence of ammonia in the bulk composition of Enceladus plays a pivotal role in its thermochemical evolution. Because ammonia reduces the melting temperature of the ice shell by 100 K below that of pure water ice, small amounts of tidal dissipation can power an “ammonia feedback” mechanism that leads to secondary differentiation of Enceladus within the ice shell. This leads to compositionally distinct zones at the base of the ice shell arranged such that a layer of lower density (and compositionally buoyant) pure water ice underlies the undifferentiated ammonia-dihydrate ice layer above. We then consider a large scale instability arising from the pure water ice layer, and use a numerical model to explore the dynamics of compositional convection within the ice shell of Enceladus. The instability of the layer can easily account for a diapir that is hemispherical in scale. As it rises to the surface, it co-advects the warm internal temperatures towards the outer layers of the satellite. This advected heat facilitates the generation of a subsurface ocean within the ice shell of Enceladus. This scenario can simultaneously account for the origin of asymmetry in surface deformation observed on Enceladus as well as two global features inferred to exist: a large density anomaly within the interior and a subsurface ocean underneath the south polar region. 相似文献