“I doubt if there's been another story quite like it”     

Derek Sears 《Meteoritics & planetary science》1993,28(3):259-259

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Place-based or sector-based adaptation? A case study of municipal and fishery policy integration     

Ahmed Khan  Anthony Charles  Derek Armitage 《Climate Policy》2018,18(1):14-23

Place-based adaptation planning is an approach to address cross-sectoral and multi-level governance concerns as well as to build local adaptive capacity in vulnerable resource-dependent communities facing the adverse impacts of climate change. In contrast, sector-based adaptation planning focuses on addressing climate change impacts on individual economic sectors (e.g. fisheries or forestry) or sub-sectors (such as lobsters or timber). Yet, linking sectoral approaches with local adaptation policies is challenging. More effort is needed to identify opportunities for complementary adaptation strategies and policy integration to foster multiple benefits. In this article, we use a case study of fishery sector resources and municipal adaptation planning in Nova Scotia to demonstrate how meaningful entry points could catalyse policy integration and lead to co-benefits across multiple levels and stakeholder groups. Drawing on a fisheries systems and fish chain framework, we identify and assess several entry points for policy integration across sector- and place-based adaptation domains within coastal habitats, as well as harvesting, processing, and marketing sectors. The analysis highlights the multiple benefits of integrating local municipal adaptation plans with multi-scale resource sectors especially towards monitoring ecosystem changes, protecting essential infrastructure, and securing local livelihoods.

POLICY RELEVANCE

Climate change is having a growing impact on coastal communities around the world, with consequences for sea-level rise, critical habitats, essential infrastructure, and multiple economic sectors and industries. This Canadian case study demonstrates how municipal adaptation initiatives can be complementary to sector-based adaptation at both local and regional levels through various entry points across commodity production chains. Policy integration across place-based and sector-based adaptation processes should lead to multiple benefits such as conserving marine biodiversity, protecting essential infrastructure, and securing livelihoods. Our analysis, which focuses specifically on the fishery sector and coastal communities, shows that these co-benefits may arise particularly in such coastal-marine systems and provide policy lessons to terrestrial systems and other sectors.  相似文献   

Comparison of methods for quantifying consumer spending on retail using publicly available data     

Derek T. Robinson  Andrei M. Balulescu 《International journal of geographical information science》2018,32(6):1061-1086

Data and estimates on the spatial distribution of consumer spending form the foundation of retail location analysis and location-allocation spatial interaction models. The presented research presents and compares four methods to estimate consumer spending that combine different levels of detail in household spending data across multiple levels of household aggregation (i.e. census units). Results demonstrate that these methods, which use publicly available census data, can capture a substantial amount of reported sales. Furthermore, comparison of the best method with the de facto industry standard for business data in Canada shows a strong correlation (R2 > 0.85) across space and is within 10% of aggregate industry-derived spending estimate. Analysis of the spending data across space finds that the majority of spending occurs in census metropolitan areas with high spending clusters that offer unique opportunities for retail location. We interrogate the socio-demographic characteristics of the population in these high spending clusters and find that only a few variables are required to explain a large proportion of the variance in consumer spending. The overarching outcome of the presented research is that small-to-medium businesses, planners, and municipalities do not need expensive proprietary data to estimate and predict consumer spending and market demand.  相似文献   

西天山达巴特A型花岗岩的形成时代与构造背景   总被引：14，自引：8，他引：6  

唐功建  陈海红  王强  赵振华  姜子琦  贾小辉 《岩石学报》2008,24(5)

达巴特花岗斑岩侵入体位于西天山北部的赛里木湖北部,构造上属于准葛尔板块与伊犁.中天山板块之间的造山带.达巴特花岗岩斑岩具有A型花岗岩的特征,如高硅(SiO2=75.38%～77.61%)、碱(Na2O K2O=8.26%～10.10%)和Fe/(Fe Mg)(0.91～0.98),但低Al2O3(12.04～12.9%)和CaO(0.03%～0.42%),富集Rb、Th、U等大离子亲石元素和Nb、Ta、zr、Hf等高场强元素,(Ga/Al)×104值变化于3.19～3.40之间,具有明显的负Eu、Ba和Sr异常,稀土配分显示"海鸥型"特征.达巴特花岗岩斑岩具有较高的Rb/Nb和Y/Nb比值,显示了A2型花岗岩的特征.LA-ICP-MS锆石U-Pb测年结果显示达巴特岩体的侵位年龄为288.9±2.3Ma,并且一些锆石具有老的核(319.0±4.7),暗示花岗岩斑的源岩中可能包含有石炭纪的岩浆岩.结合区域地质和岩浆岩资料,我们认为西天山早二叠世处于伸展的背景中,可能与造山带后碰撞阶段的演化有关.  相似文献   

Returns from a speculation     

Ron Johnston  Derek Gregory  Geraldine Pratt  Michael Watts  Sarah Whatmore 《Geoforum》2008,39(3):1105-1107

A reply to a recent paper by Setten.  相似文献   

Novel preparation of sensitized ZnS nanoparticles and its use in photocatalytic degradation of tetracycline     

M. Ahadi  M. Saber Tehrani  P. Aberoomand Azar  S. Waqif Husain 《International Journal of Environmental Science and Technology》2016,13(12):2797-2804

Sensitized ZnS nanoparticles were synthesized by chemical precipitation method using anthocyanin as the capping agent and sensitizer. X-ray diffractometer, field-emission scanning electron microscope, transmission electron microscopy, UV visible spectrophotometer, Fourier transform infrared spectroscopy and photoluminescence spectrometry methods were used for the characterization of nanoparticles. The electron microscopy studies of nanoparticles showed that the size of crystallites is in the range of 35–80 nm and optical studies showed a blue shift in the absorption edge by adding capping agent. The effective band gap energy was increased with decrease in the particle size. Photocatalytic activities of sensitized ZnS and pure ZnS were evaluated by degradation of tetracycline in aqueous solution under visible light irradiation, and progress of the reaction was monitored spectrophotometrically. The different parameters affecting degradation such as the pH of solution, amount of semiconductor and reusability of catalyst for three cycles and the photocatalytic degradation kinetics of tetracycline were studied. More than 80% degradation was achieved within 5 h under visible light.  相似文献   

Grain contacts in crystalline rocks     

Derek Flinn 《Lithos》1969,2(4):361-370

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Hydrologic metrics for status‐and‐trends monitoring in urban and urbanizing watersheds          下载免费PDF全文

Derek B. Booth  Christopher P. Konrad 《水文研究》2017,31(25):4507-4519

Local governmental agencies are increasingly undertaking potentially costly “status‐and‐trends” monitoring to evaluate the effectiveness of stormwater control measures and land‐use planning strategies or to satisfy regulatory requirements. Little guidance is presently available for such efforts, and so we have explored the application, interpretation, and temporal limitations of well‐established hydrologic metrics of runoff changes from urbanization, making use of an unusually long‐duration, high‐quality data set from the Pacific Northwest (USA) with direct applicability to urban and urbanizing watersheds. Three metrics previously identified for their utility in identifying hydrologic conditions with biological importance that respond to watershed urbanization—T_Qmean (the fraction of time that flows exceed the mean annual discharge), the Richards‐Baker Index (characterizing flashiness relative to the mean discharge), and the annual tally of wet‐season day‐to‐day flow reversals (the total number of days that reverse the prior days' increasing or decreasing trend)—are all successful in stratifying watersheds across a range of urbanization, as measured by total contributing area of urban development. All metrics respond with statistical significance to multidecadal trends in urbanization, but none detect trends in watershed‐scale urbanization over the course of a single decade. This suggests a minimum period over which dependable trends in hydrologic alteration (or improvement) can be detected with confidence. The metrics also prove less well suited to urbanizing watersheds in a semi‐arid climate, with only flow reversals showing a response consistent with prior findings from more humid regions. We also explore the use of stage as a surrogate for discharge in calculating these metrics, recognizing potentially significant agency cost savings in data collection with minimal loss of information. This approach is feasible but cannot be implemented under current data‐reporting practices, requiring measurement of water‐depth values and preservation of the full precision of the original recorded data. With these caveats, however, hydrologic metrics based on stage should prove as or more useful, at least in the context of status‐and‐trends monitoring, as those based on subsequent calculations of discharge.  相似文献   

The effects of thermal stress and fluid pressure on induced seismicity during stimulation to production within fractured reservoirs     

Ghazal Izadi  Derek Elsworth 《地学学报》2013,25(5):374-380

We use a continuum model of reservoir evolution to explore the interaction of coupled thermal, hydraulic and chemical processes that influence the evolution of seismicity within a fractured reservoir from stimulation to production. Events occur from energy release on seeded fractures enabling moment magnitude, frequency and spatial distribution to be determined with time. Event magnitudes vary in the range ?2 to +2 with the largest event size (~2) corresponding to the largest fracture size (~500 m) and a prescribed stress drop of 9 MPa. Modelled b‐values (~0.6–0.7) also correspond to observations (~0.7–0.8) for response in the Cooper Basin (Australia). We track the hydrodynamic and thermal fronts to define causality in the triggering of seismicity. The hydrodynamic front moves twice as fast as the thermal front and envelops the triggered seismicity at early time (days to month) – with higher flow rates correlating with larger magnitude events. For later time (month to years), thermal drawdown and potentially chemical influences principally trigger the seismicity, but result in a reduction in both the number of events and their magnitudes.  相似文献   

Re‐orientation of the extension direction and pure extensional faulting at oblique rift margins: comparison between the Main Ethiopian Rift and laboratory experiments     

Giacomo Corti  Melody Philippon  Federico Sani  Derek Keir  Tesfaye Kidane 《地学学报》2013,25(5):396-404

In this study, we draw on a unique combination of well‐resolved fault‐slip data and earthquake focal mechanisms to constrain spatial variations in style of faulting in the obliquely extending Main Ethiopian Rift, East Africa. These data show that both boundary and internal faults – oblique and orthogonal to the plate divergence (PD) respectively – exhibit almost pure dip‐slip motion, and indicate significant local deflection in orientation of the extension direction at rift margins. Scaled analogue models closely replicate the multidisciplinary observations from the rift and suggest that the process is controlled by the presence of a deep‐seated, pre‐existing weakness – oblique to the direction of PD – that is able to cause a local rotation in the orientation of the extension direction at rift margins. Minor counterclockwise block rotations are required to accommodate the difference in slip direction along the different fault systems, as supported by existing and new palaeomagnetic data from the rift.  相似文献