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101.
This article presents a GIS‐based methodology to integrate a measure of geographic attractiveness of localities in the process of allocating potential dwellings in the context of a large urban region. The methodology was developed for a study area in Brisbane‐South East Queensland (SEQ), known as the Sunbelt Region, a rapidly growing region and a popular tourist destination in Australia. In this article, we have used a multivariate technique to develop a set of parameterised linear equations to define underlying dimensions that drive residential location decision choices. Aesthetic and accessibility factors were identified in the factor analysis from data collected via a survey of Quality of Life. Spatial measures were based on a combination of network distance and kernel density estimation to calculate ‘aesthetic’ and ‘accessibility’ scenarios, which were then overlaid and multiplied by their subjective weights to create an ‘overall attractiveness scenario’. These development scenarios were integrated as a set of criteria to control the allocation of potential dwelling capacity over the next 25 years at a grid cell level.  相似文献   
102.
We identify and assess the relative importance of the principal factors influencing the release of dissolved organic carbon (DOC) and dissolved forms of nitrogen (N) from a small upland headwater dominated by podzolic soils during a sequence of autumn runoff events. We achieve this by subjecting high‐resolution hydrometeorological and hydrochemical data to an R‐mode principal component factor analysis and a stepwise multivariate regression analysis. We find that the release of DOC and N is influenced by four principal factors, namely event magnitude, soil water flow through the Bs horizon, the length of time since the soil profile was last flushed, and rewetting of the H horizon. The release of DOC and dissolved organic nitrogen (DON) is most strongly influenced by the combination of event magnitude and soil water flow through the Bs horizon, and to a lesser extent by the length of time since the soil profile was last flushed. Rewetting of the H horizon also influences the release of DOC, but this is not the case for DON. The release of nitrate (NO3‐N) is most strongly influenced by the combination of the length of time since the soil profile was last flushed and rewetting of the H horizon, and to a lesser extent by event magnitude. Soil water flow through the Bs horizon does not influence the release of NO3‐N. We argue that the mechanisms by which the above factors influence the release of DOC and N are probably strongly associated with moisture‐dependent biological activity, which governs the turnover of organic matter in the soil and limits the availability of NO3‐N in the soil for leaching. We conclude that the release of DOC and N from upland headwaters dominated by podzolic soils is largely controlled by the variable interaction of hydrometeorological factors and moisture‐dependent biological processes, and that a shift in climate towards drier summers and wetter winters may result in the release of DOC and N becoming increasingly variable and more episodic in the future. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
103.
Drifting sediment traps were deployed at 9 stations in May-June (ice-covered conditions) and July-August (ice-free conditions) 2004 in the Chukchi Sea to investigate the variability in export fluxes of biogenic matter in the presence and absence of sea ice cover. Measurements of chlorophyll-a (Chl-a), particulate organic carbon (POC), particulate nitrogen (PN), phytoplankton, zooplankton fecal pellets, and the stable carbon isotope composition (δ13C) of the sinking material were performed along Barrow Canyon (BC) and a parallel shelf-to-basin transect from East Hanna Shoal (EHS) to the Canada Basin. POC export fluxes were similarly high in the presence (378±106 mg C m−2 d−1) and in the absence of ice cover (442±203 mg C m−2 d−1) at the BC stations, while fluxes were significantly higher in the absence (129±98 mg C m−2 d−1) than in the presence of ice cover (44±29 mg C m−2 d−1) at the EHS stations. The C/N ratios and δ13C values of sinking organic particles indicated that POC export fluxes on the Chukchi continental shelf were mostly composed of freshly produced labile material, except at the EHS stations under ice cover where the exported matter was mostly composed of refractory material probably advected into the EHS region. Chl-a fluxes were higher under ice cover than in ice-free water, however, relatively low daily loss rates of Chl-a and similar phytoplankton carbon fluxes in ice-covered and ice-free water suggest the retention of phytoplankton in the upper water column. An increase in fecal pellet carbon fluxes in ice-free water reflected higher grazing pressure in the absence of ice cover. Elevated daily loss rates of POC at the BC stations confirmed other indications that Barrow Canyon is an important area of carbon export to the basin and/or benthos. These results support the conclusion that there are large spatial and temporal variations in export fluxes of biogenic matter on the Chukchi continental shelf, although export fluxes may be similar in the presence and in the absence of ice cover in highly productive regions.  相似文献   
104.
Patterns of social interaction influence how knowledge is generated, communicated, and applied. Theories of social capital and organizational learning suggest that interactions within disciplinary or functional groups foster communication of knowledge, whereas interactions across groups foster generation of new knowledge. We used social network analysis to examine patterns of social interaction reported in survey data from scientists and managers who work on fish and fire issues. We found that few fish and fire scientists and managers interact with one another, suggesting low bridging social capital and thus, limited opportunity for generation of new knowledge. We also found that although interaction occurs among scientists—suggesting modest bonding social capital—few managers interact with other managers, indicating limited opportunity for communication of scientific knowledge for the purposes of application. We discuss constraints and opportunities for organizational learning evident in these patterns of social interaction among fish and fire scientists and managers.  相似文献   
105.
The late Cretaceous A-type Karaçay?r pluton in Central Anatolia, Turkey, intrudes and entrains xenoliths of Palaeozoic limestone. Carbonatitic magmatic rocks within the syenite have been previously interpreted (Schuiling in Nature, 192:1280, 1961) to result from metasomatic alteration and syntectic melting of marble. Carbonatites and associated calcite-syenites exhibit mineralogical characteristics (Ab-rich plagioclase, Ba-rich K-feldspar, low-Mg# biotite) that are petrogenetically more evolved than the host syenitic suite. Geochemically, carbonate-rich magmatic rocks are greatly enriched in Sr, Ba, Th, and REE and have higher LREE/HREE ratios than either syenites or marbles. In terms of O-C-Sr-Pb isotope ratios, the carbonatite/calcite-syenite suite form a consistent and geochemically coherent group that is distinct from the marble country rock and xenolith population, but similar to some of the syenitic, and particularly the nepheline syenite components of the Karaçay?r pluton. Other silicate magmatic rocks are geochemically, isotopically, and geochronologically different, suggesting the pluton is composite. Overall, the mineralogical and geochemical characteristics of the carbonatites are incompatible with binary mixing of syenite and marble but are consistent with derivation of carbonatite from petrogenetically evolved foid syenite. Carbonate–silicate rock types have modal variations compatible with an origin by fractional crystallisation, rather than by liquid immiscibility.  相似文献   
106.
The behaviour of offshore‐directed winds over coastal dune and beach morphology was examined using a combination of modelling (3‐D computational fluid dynamics (CFD)) and field measurement. Both model simulations and field measurements showed reversal of offshore flows at the back beach and creation of an onshore sediment transport potential. The influence of flow reversals on the beach‐dune transport system and foredune growth patterns has previously received little attention. Detailed wind flow measurements were made using an extensive array of mast‐mounted, 3‐D ultrasonic anemometers (50 Hz), arranged parallel to the dominant incident wind direction. Large eddy simulation (LES) of the offshore wind flow over the dune was conducted using the open‐source CFD tool openFOAM. The computational domain included a terrain model obtained by airborne LiDAR and detailed ground DGPS measurements. The computational grid (~22 million cells) included localized mesh refinement near the complex foredune terrain to capture finer details of the dune morphology that might affect wind flows on the adjacent beach. Measured and simulated wind flow are presented and discussed. The CFD simulations offer new insights into the flow mechanics associated with offshore winds and how the terrain steering of wind flow impacts on the geomorphological behaviour of the dune system. Simulation of 3‐D wind flows over complex terrain such as dune systems, presents a valuable new tool for geomorphological research, as it enables new insights into the relationship between the wind field and the underlying topography. The results show that offshore and obliquely offshore winds result in flow reversal and onshore directed winds at distances of up to 20 m from the embryo dune toe. The potential geomorphological significance of the findings are discussed and simple calculations show that incoming offshore and obliquely offshore winds with mean velocities over 13 m s?1 and 7 m s?1, respectively, have the potential to create onshore‐directed winds at the back beach with mean velocities above 3.3 m s?1. These are above the threshold of movement for dry sand and support previous conclusions about the significance of offshore winds in dune and beach budget calculations. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
107.
The history of development of Integrated Coastal Zone Management (ICZM) in Northern Ireland is described here in the context of European and UK initiatives. The current structures for ICZM in Northern Ireland involve a formal strategy. This involves a number of specific actions in the environmental, social, and economic spheres with specific goals pertaining to integration. The strategy has been agreed by all responsible organisations (both governmental and NGOs), and each action is time-bound and has an identified responsible agency. The Northern Ireland Coastal and Marine Forum (NICMF) which consists of non-governmental members, has the task of monitoring the implementation of the strategy and acting as a catalyst for integration. The strengths of the current structure lie in the presence of an integrating ICZM strategy and the fact that the initiative is government-led in response to the EU Recommendation on ICZM. These provide better levels of sustainability and links to the statutory system of governance compared to the partnership model in Great Britain. Its main weaknesses are: (i) that the NICMF relies on voluntary participation; (ii) linkages between government departments have not been substantially improved; and (iii) weak mechanisms for ensuring goals are achieved.  相似文献   
108.
We present an annually resolved reconstruction of spring-summer precipitation variability in East Anglia, UK (52–53°N, 0–2°E) for the period AD 900–2009. A continuous regional network of 723 living (AD 1590–2009) and historical (AD 781–1790) oak (Quercus sp.) ring-width series has been constructed and shown to display significant sensitivity to precipitation variability during the March-July season. The existence of a coherent common growth signal is demonstrated in oaks growing across East Anglia, containing evidence of near-decadal aperiodic variability in precipitation throughout the last millennium. Positive correlations are established between oak growth and precipitation variability across a large region of northwest Europe, although climate-growth relationships appear time transgressive with correlations significantly weakening during the early twentieth century. Examination of the relationship between oak growth, precipitation, and the North Atlantic Oscillation (NAO), reveals no evidence that the NAO plays any significant role in the control of precipitation or tree growth in this region. Using Regional Curve Standardisation to preserve evidence of low-frequency growth variability in the East Anglian oak chronology, we produce a millennial length reconstruction that is capable of explaining 32–35% of annual-to-decadal regional-scale precipitation variance during 1901–2009. The full length reconstruction indicates statistically significant anomalous dry conditions during AD 900–1100 and circa-1800. An apparent prolonged wetter phase is estimated for the twelfth and thirteen centuries, whilst precipitation fluctuates between wetter and drier phases at near centennial timescales throughout the fourteenth to seventeenth centuries. Above average precipitation reconstructed for the twenty-first century is comparable with that reproduced for the 1600s. The main estimated wet and dry phases reconstructed here appear largely coherent with an independent tree-ring reconstruction for southern-central England.  相似文献   
109.
An experimental study of water fluxes from roofs in a residential area has quantified water fluxes from different types of roof and identified the major controls on the process. Roofs with pitches of 0°, 22° and 50° and orientations of 15° (from true north) (NNE) and 103° (ESE) were selected. A novel automatic system for monitoring has been developed. Noticeable differences in rainfall, runoff and evaporation were found for different roof slopes, aspects and heights. Depending on height, flat roofs collected 90 to 99% of rainfall recorded at ground level. Roofs with a 22° slope; facing south‐south‐west (i.e. facing the prevailing wind) captured most rain, whereas east‐south‐east facing roofs with slopes of 50° received the least. Depending on the roof slope, the average rainfall captured ranged from 62 to 93% of that at ground level. For the same slope, the results indicated that from roofs orientated normal to the prevailing wind; (i) captured rainfall was higher, (ii) evaporation was higher and (iii) runoff was less than that from roofs having other aspects. Monthly variations in the runoff–rainfall ratio followed the rainfall distribution, being lowest in summer and highest in winter. The highest mean ratio (0·91) was associated with the steeper roof slope; the lowest ratio (0·61) was for roofs facing the prevailing wind direction. For the same amount of rainfall, the runoff generated from a steeper roof was significantly higher than that generated by a moderate roof slope, but the lowest runoff was from roofs facing the prevailing wind. The results have also shown that the amount of runoff collected (under UK climatic condition) was sufficient to supply an average household in the studied area with the major part of its annual water requirements. The use of this water not only represents a financial gain for house owners but also will help protect the environment by reducing demand on water resources through the reduction of groundwater abstraction, construction of new reservoirs, and a reduction of the flood risk as its in situ use is considered a preventive measure known as a source control. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
110.
A low-voltage (≤3.3 V) imaging technology has been developed to enable scientific-grade imagers with low-power complex functions on chip. A 128 × 128 CCD imager with on-chip clocking and charge-domain analog-to-digital conversion, as well as an exploratory active pixel sensor have been demonstrated. A 640 × 960 CCD imager with optimized 12 bit charge-domain conversion and an improved active pixel sensor are presently in fabrication. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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