Recontextualising inshore fisheries: The changing face of British inshore fisheries management     

Jeremy Phillipson  David Symes 《Marine Policy》2010

Inshore fisheries are coming under increasing pressure to account for wider environmental impacts and relations with other users of marine space. However approaches to inshore fisheries management across Britain’s devolved governments are becoming even more strikingly divergent. While in England the century old local Sea Fisheries Committees are to be replaced with modernised structures, and in Scotland there are efforts to move to a locally driven management system, in Wales there has been a retreat from local co-management. Not only do the reforms pose ongoing challenges for good governance, not least in the handling of cross-scale interactions and user group participation, but they may also fall short in providing for systematic and full integration of fisheries and marine environmental management.  相似文献   

Optimizing compaction calculation for improved probabilistic 2D mapping     

Olena Babak  Kun Liu  Jeremy Gallop 《Geophysical Prospecting》2019,67(3):595-608

Integration of all available data in reservoir characterization is critically important. 2D mapping is a reliable and robust technique that allows integration of multiple secondary data, including geological and geophysical surfaces and maps, to generate realistic summaries of reservoir quality at each location in an area of interest with an associated measure of uncertainty. This is achieved in 2D mapping with a more straightforward implementation, requiring significantly less time and fewer resources than three-dimensional modelling. In this paper, we propose an approach for the empirical calculation and optimization of differential compaction maps by leveraging existing well control for the use in 2D mapping. Success of the proposal is demonstrated through tests of accuracy, precision and fairness of the local uncertainty distributions for 100 new stratigraphical wells drilled in the Christina Lake and Kirby East area.  相似文献   

Coastal protection using building with nature concept: A case study from Chongming Dongtan Shoal,China     

Zhentao Chong  Min Zhang  Jiahong Wen  Luyang Wang  Jie Mi  Jeremy Bricker  Stanley Nmor  Zhijun Dai 《海洋学报(英文版)》2021,40(10):152-166

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Impact of model free parameters and sea-level rise uncertainties on 20-years shoreline hindcast: the case of Truc Vert beach (SW France)     

Maurizio D'Anna  Déborah Idier  Bruno Castelle  Gonéri Le Cozannet  Jeremy Rohmer  Arthur Robinet 《地球表面变化过程与地形》2020,45(8):1895-1907

Shoreline change is driven by various complex processes interacting at a large range of temporal and spatial scales, making shoreline reconstructions and predictions challenging and uncertain. Despite recent progress in addressing uncertainties related to the physics of sea-level rise, very little effort is made towards understanding and reducing the uncertainties related to wave-driven shoreline response. To fill this gap, the uncertainties associated with the long-term modelling of shoreline change are analysed at a high-energy cross-shore transport dominated site. Using the state-of-the-art LX-Shore shoreline change model, we produce a probabilistic shoreline reconstruction, based on 3000 simulations over the past 20 years at Truc Vert beach, southwest France, whereby sea-level rise rate, depth of closure and three model free parameters are considered uncertain variables. We further address the relative impact of each source of uncertainty on the model results performing a Global Sensitivity Analysis. This analysis shows that the shoreline changes are mainly sensitive to the three parameters of the wave-driven model, but also that the sensitivity to each of these parameters is strongly modulated seasonally and interannually, in relation with wave energy variability, and depends on the time scale of interest. These results have strong implications on the model skill sensitivity to the calibration period as well as for the predictive skill of the model in a context of future climate change affecting wave climate and extremes. © 2020 John Wiley & Sons, Ltd.  相似文献   

The intermingling of benthic macroinvertebrate communities during a period of shifting range: The “East of Nantucket” Atlantic Surfclam Survey and the existence of transient multiple stable states     

Eric N. Powell  Roger Mann  Kelsey M. Kuykendall  M. Chase Long  Jeremy R. Timbs 《Marine Ecology》2019,40(4)

A survey of the region eastward of Nantucket provided an opportunity to examine the cold temperate–boreal boundary along the high‐energy Great South Channel. Here described are the benthic macroinvertebrate community types encountered, with a focus on the influence of climate change on the range boundaries of the benthic biomass dominants and the potential existence of transient multiple stable states. The survey identified three primary community types. The shallowest sites were occupied by a surfclam‐dominated community, comprising an abundance of large (≥150 mm) surfclams, and a few common attached epibiota primarily attached to exposed surfclam shell. Two communities exist at intermediate depths, one dominated by submarket and small market‐size surfclams (<150 mm) and the other, created by mussel mats and their attendant epibiota, crabs, sea urchins, and other mobile epifauna. Mussels are a foundational species, establishing a hard‐bottom terrain conducive to these other denizens in soft‐bottom habitat. Cobbles were nearly ubiquitous, rocks were routinely recovered, and boulders were encountered occasionally. Slow growing attached epibionts were exceedingly rare and mobile epifauna were not obviously associated with these large sedimentary particles; nor were the surfclam or mussel communities. The frequency of barnacle scars suggests sediment scour under the high‐flow regime characteristic of the surveyed region, which voids the habitat potential of these sedimentary particles. The abundance of surfclam shell indicates that surfclams have inhabited the shoaler depths for an extended time; limited shell at deeper sites supports the inference from the absence of large animals that these sites are relatively newly colonized and represent further evidence of an offshore shift in range brought on by increasing bottom water temperatures. The dichotomous nature of the two primary community types at mid‐depths suggests that these two communities represent multiple stable states brought on by the interaction of an invading cold temperate species with the receding boreal fauna resulting in a transient intermingling of species, which, however, structure the habitat into exclusionary stable states rather than overlapping in a co‐occurrence ecotone.  相似文献   

VGTrust: measuring trust for volunteered geographic information     

Jeremy Severinsen  Femke Reitsma  Emir Hartato 《International journal of geographical information science》2019,33(8):1683-1701

Volunteered Geographic Information (VGI) has emerged as a large, up-to-date, and easily accessible data source. VGI can allow authoritative mapping agencies to undertake continuous improvement of their own data, adding a currency dimension previously unattainable due to high associated costs. VGI also benefits scientific and social research by facilitating quick and low-cost research data capture by the public. VGI, however, through its diversity of authorship, presents a quality assurance risk to the use of this data. This research presents a formulaic model that addresses VGI quality issues, by quantifying trust in VGI. Our ‘VGTrust’ model assesses information about a data author, and the spatial and temporal trust associated with the data they create, to produce an overall VGTrust rating metric. This metric is both easy to understand and interpret. A facilitated case study, ‘Building Our Footprints’ is presented which tests the feasibility of VGTrust model in a real-world data capture exercise run by Land Information New Zealand, New Zealand’s mapping organisation. By overcoming the trust issues in VGI, this research will allow the integration of VGI and authoritative data and potentially expand the application of VGI, thereby leveraging the power of the crowd for productive and innovative re-use.  相似文献   

A preliminary study of habitat and resource partitioning among co-occurring tropical dolphins around Mayotte, southwest Indian Ocean     

Alexandra Gross  Jeremy Kiszka  Olivier Van Canneyt  Pierre Richard  Vincent Ridoux   《Estuarine, Coastal and Shelf Science》2009,84(3):367

Mayotte in the southwest Indian Ocean is characterized by high dolphin diversity. They may coexist within a fairly small area around the island because they exploit neither the same preferential habitats nor the same resources. This preliminary study aimed to investigate ecological niche segregation among these delphinid communities: the Indo-Pacific bottlenose dolphin, Tursiops aduncus, the pantropical spotted dolphin, Stenella attenuata, the spinner dolphin, Stenella longirostris, and the melon-headed whale, Peponocephala electra. Two approaches were used. Habitat preferences were investigated by analysing dolphin sighting data and associated physiographical characteristics. Resource partitioning was explored by analysing C and N stable isotopes in skin and blubber biopsies. Only T. aduncus, which showed clear association with coastal habitats in the lagoon, differed from the others in terms of habitat preferences, characterised by shallow depth and slope, and proximity to the coast. All other species shared similar oceanic habitats immediately outside the lagoon, these being of higher depth and slope, greater distance from the coast and were not discernable by discriminant analysis. The two Stenella species and the melon-headed whale displayed very high overlap in habitat physiographic variables. The analysis of stable isotopes confirmed the ecological isolation of T. aduncus and revealed a clear segregation of P. electra compared to the two Stenella that was not apparent in the habitat analysis. This may reflect ecological differences that were not observable from diurnal surface observations.  相似文献   

Aquifer Characterization and Uncertainty in Multi-Frequency Oscillatory Flow Tests: Approach and Insights     

Jeremy R. Patterson  Michael Cardiff 《Ground water》2022,60(2):180-191

Characterizing aquifer properties and their associated uncertainty remains a fundamental challenge in hydrogeology. Recent studies demonstrate the use of oscillatory flow interference testing to characterize effective aquifer flow properties. These characterization efforts relate the relative amplitude and phase of an observation signal with a single frequency component to aquifer diffusivity and transmissivity. Here, we present a generalized workflow that relates extracted Fourier coefficients for observation signals with single and multiple frequency components to aquifer flow properties and their associated uncertainty. Through synthetic analytical modeling we show that multi-frequency oscillatory flow interference testing adds information that improves inversion performance and decreases parameter uncertainty. We show increased observation signal length, sampling frequency, and pressure sensor accuracy all produce decreased parameter uncertainty. This work represents the first attempt we are aware of to quantify effective aquifer parameters and their associated uncertainty using multi-frequency oscillatory flow interference testing.  相似文献   

Heterogeneous distribution of H2O in the Martian interior: Implications for the abundance of H2O in depleted and enriched mantle sources          下载免费PDF全文

Francis M. McCubbin  Jeremy W. Boyce  Poorna Srinivasan  Alison R. Santos  Stephen M. Elardo  Justin Filiberto  Andrew Steele  Charles K. Shearer 《Meteoritics & planetary science》2016,51(11):2036-2060

We conducted a petrologic study of apatite within 12 Martian meteorites, including 11 shergottites and one basaltic regolith breccia. These data were combined with previously published data to gain a better understanding of the abundance and distribution of volatiles in the Martian interior. Apatites in individual Martian meteorites span a wide range of compositions, indicating they did not form by equilibrium crystallization. In fact, the intrasample variation in apatite is best described by either fractional crystallization or crustal contamination with a Cl‐rich crustal component. We determined that most Martian meteorites investigated here have been affected by crustal contamination and hence cannot be used to estimate volatile abundances of the Martian mantle. Using the subset of samples that did not exhibit crustal contamination, we determined that the enriched shergottite source has 36–73 ppm H₂O and the depleted source has 14–23 ppm H₂O. This result is consistent with other observed geochemical differences between enriched and depleted shergottites and supports the idea that there are at least two geochemically distinct reservoirs in the Martian mantle. We also estimated the H₂O, Cl, and F content of the Martian crust using known crust‐mantle distributions for incompatible lithophile elements. We determined that the bulk Martian crust has ~1410 ppm H₂O, 450 ppm Cl, and 106 ppm F, and Cl and H₂O are preferentially distributed toward the Martian surface. The estimate of crustal H₂O results in a global equivalent surface layer (GEL) of ~229 m, which can account for at least some of the surface features on Mars attributed to flowing water and may be sufficient to support the past presence of a shallow sea on Mars' surface.  相似文献   

The late Oligocene Cevizlidere Cu-Au-Mo deposit,Tunceli Province,eastern Turkey     

Ali İmer  Jeremy P. Richards  Robert A. Creaser  Terry L. Spell 《Mineralium Deposita》2015,50(2):245-263

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