Fisheries mismanagement     

O'Leary BC  Smart JC  Neale FC  Hawkins JP  Newman S  Milman AC  Roberts CM 《Marine pollution bulletin》2011,62(12):2642-2648

We analysed the extent to which European politicians have adhered to scientific recommendations on annual total allowable catches (TACs) from 1987 to 2011, covering most of the period of the Common Fisheries Policy (CFP). For the 11 stocks examined, TACs were set higher than scientific recommendations in 68% of decisions. Politically-adjusted TACs averaged 33% above scientifically recommended levels. There was no evidence that the 2002 reform of the CFP improved decision-making, as was claimed at the time. We modelled the effects of such politically-driven decision-making on stock sustainability. Our results suggest that political adjustment of scientific recommendations dramatically increases the probability of a stock collapsing within 40 years.In 2012 European fisheries policy will undergo a once-a-decade reform. Ten years ago radical reforms were promised but the changes failed to improve sustainability. It is likely that the 2012 reform will be similarly ineffective unless decision-making is changed so that catch allocations are based on science rather than politics.  相似文献   

Comparison of nitrate attenuation characterization methods at the Uranium mill tailing site in Monument Valley, Arizona     

Kenneth C. Carroll  Fiona L. Jordan  Edward P. Glenn  W. Jody Waugh  Mark L. Brusseau   《Journal of Hydrology》2009,378(1-2):72-81

Several methods for characterizing the occurrence and rate of nitrate attenuation were tested at a field site near Monument Valley, Arizona. Spatial and temporal nitrate concentration data collected from a transect of monitoring wells located along the plume centerline were analyzed to evaluate the overall rates of natural attenuation. The occurrence and rate of denitrification was evaluated through microcosm experiments, nitrogen isotopic fractionation analysis, and solute-transport modeling. First-order denitrification-rate coefficients calculated with each method were comparable. In addition, the composite natural attenuation rate coefficient was similar to the denitrification-rate coefficients, which suggests that microbially induced decay primarily controls nitrate attenuation at the site. This research highlights the benefits associated with a multiple-method approach for the characterization of natural attenuation.  相似文献   

Higher order clustering in the Durham/UKST and Stromlo–APM Galaxy Redshift Surveys     

Fiona Hoyle  Istvan Szapudi†  Carlton M. Baugh 《Monthly notices of the Royal Astronomical Society》2000,317(3):L51-L56

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Origin and transportation history of lunar breccia 14311          下载免费PDF全文

Renaud E. Merle  Alexander A. Nemchin  Martin J. Whitehouse  Robert T. Pidgeon  Marion L. Grange  Joshua F. Snape  Fiona Thiessen 《Meteoritics & planetary science》2017,52(5):842-858

In this paper, we compare the U‐Pb zircon age distribution pattern of sample 14311 from the Apollo 14 landing site with those from other breccias collected at the same landing site. Zircons in breccia 14311 show major age peaks at 4340 and 4240 Ma and small peaks at 4110, 4030, and 3960 Ma. The zircon age patterns of breccia 14311 and other Apollo 14 breccias are statistically different suggesting a separate provenance and transportation history for these breccias. This interpretation is supported by different U‐Pb Ca‐phosphate and exposure ages for breccia 14311 (Ca‐phosphate age: 3938 ± 4 Ma, exposure age: ~550–660 Ma) from the other Apollo 14 breccias (Ca‐phosphate age: 3927 ± 2 Ma, compatible with the Imbrium impact, exposure age: ~25–30 Ma). Based on these observations, we consider two hypotheses for the origin and transportation history of sample 14311. (1) Breccia 14311 was formed in the Procellarum KREEP terrane by a 3938 Ma‐old impact and deposited near the future site of the Imbrium basin. The breccia was integrated into the Fra Mauro Formation during the deposition of the Imbrium impact ejecta at 3927 Ma. The zircons were annealed by mare basalt flooding at 3400 Ma at Apollo 14 landing site. Eventually, at approximately 660 Ma, a small and local impact event excavated this sample and it has been at the surface of the Moon since this time. (2) Breccia 14311 was formed by a 3938 Ma‐old impact. The location of the sample is not known at that time but at 3400 Ma, it was located nearby or buried by hot basaltic flows. It was transported from where it was deposited to the Apollo 14 landing site by an impact at approximately 660 Ma, possibly related to the formation of the Copernicus crater and has remained at the surface of the Moon since this event. This latter hypothesis is the simplest scenario for the formation and transportation history of the 14311 breccia.  相似文献   

Influence of environmental and prey variables on low tide shorebird habitat use within the Robbins Passage wetlands,Northwest Tasmania   总被引：1，自引：0，他引：1  

Fiona L. Spruzen  Alastair M.M. RichardsonEric J. Woehler 《Estuarine, Coastal and Shelf Science》2008

Shorebirds feed primarily on tidal flats, and their distribution over these flats is influenced by their prey and abiotic factors. These factors act by influencing the distribution and abundance of the prey, or the shorebirds ability to exploit it. The aims of this study were to investigate the low tide foraging distribution of shorebirds at four sites within the Robbins Passage wetlands, and the environmental and invertebrate factors that may influence their distribution. The greatest densities and number of shorebirds were found at Shipwreck Point and East Inlet. The shorebirds within-site distribution was also non-random, with the shorebirds present in greatest densities at the water's edge and low intertidal stratum, although this varied among species. Generally, on a small spatial scale, invertebrate diversity was positively correlated, and seagrass leaf mass was negatively correlated, with shorebird feeding density. On a large spatial scale, invertebrate biomass and seagrass root mass were positively correlated with shorebird feeding density. Invertebrate biomass and seagrass root mass explained 71% of the variance in total shorebird feeding density on the tidal flats. The variation in shorebird feeding density and diversity was therefore partly explained by invertebrate diversity and biomass, as well as the environmental factors seagrass roots and leaf mass and tidal flat area, although the strength of these relationships was influenced by the two different spatial scales of the study. The strength of the relationships between shorebird feeding density and the invertebrate and environmental variables was stronger on a large spatial scale. The presence of seagrass may have influenced shorebird-feeding density by affecting the invertebrate abundance and composition or the shorebirds ability to detect and capture their prey. The area of the tidal flat had opposing effects on the shorebird species. These results can be used to assist in the development of management plans for the Robbins Passage wetlands and the conservation of important shorebird areas.  相似文献   

Can a photometric redshift code reliably determine dust extinction?     

T. S. R. Babbedge  R. Whitaker  S. Morris † 《Monthly notices of the Royal Astronomical Society》2005,361(2):437-450

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Galaxy groups at 0.3 ≤z≤ 0.55 – II. Evolution to z∼ 0     

D. J. Wilman †  M. L. Balogh ‡  R. G. Bower  J. S. Mulchaey  A. Oemler  Jr    R. G. Carlberg  V. R. Eke  I. Lewis  S. L. Morris  R. J. Whitaker 《Monthly notices of the Royal Astronomical Society》2005,358(1):88-100

We compare deep Magellan spectroscopy of 26 groups at  0.3 ≤ z ≤ 0.55  , selected from the Canadian Network for Observational Cosmology 2 field survey, with a large sample of nearby groups from the 2PIGG catalogue. We find that the fraction of group galaxies with significant [O  ii ]λ3727 emission (≥5 Å) increases strongly with redshift, from ∼29 per cent in 2dFGRS to ∼58 per cent in CNOC2, for all galaxies brighter than  ∼ M _*+ 1.75  . This trend is parallel to the evolution of field galaxies, where the equivalent fraction of emission-line galaxies increases from ∼53 to ∼75 per cent. The fraction of emission-line galaxies in groups is lower than in the field, across the full redshift range, indicating that the history of star formation in groups is influenced by their environment. We show that the evolution required to explain the data is inconsistent with a quiescent model of galaxy evolution; instead, discrete events in which galaxies cease forming stars (truncation events) are required. We constrain the probability of truncation ( P _trunc) and find that a high value is required in a simple evolutionary scenario neglecting galaxy mergers  ( P _trunc≳ 0.3 Gyr⁻¹)  . However, without assuming significant density evolution, P _trunc is not required to be larger in groups than in the field, suggesting that the environmental dependence of star formation was embedded at redshifts   z ≳ 0.45  .  相似文献   

Excursion to Upnor: Saturday,May 8th, 1880     

William Whitaker 《Proceedings of the Geologists' Association. Geologists' Association》1880,6(7):336-337

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Collating Historic Weather Observations for the East Asian Region:Challenges,Solutions,and Reanalyses     

Fiona WILLIAMSON  Rob ALLAN  Guoyu REN  Tsz-cheung LEE  Wing-hong LUI  Hisayuki KUBOTA  Jun MATSUMOTO  Jürg LUTERBACHER  Clive WILKINSON  Kevin WOOD 《大气科学进展》2018,35(8):899-904

正1.Introduction Historic instrumental weather observations,made on land or at sea from as early as the 17th century(e.g.,Camuffo et al.,2010),are integral to extending our understanding of the decadal and centennial variations of Earth’s climate and for comparison with paleo-proxy data.The potential of such data is shown to best effect when used in dynamical 4D global  相似文献   

Contested geographical imaginings of reunification: A case study of urban change in Leipzig     

Fiona M. Smith 《Applied geography (Sevenoaks, England)》1997,17(4):355-369

Geopolitics and city restructuring are typically regarded as separate scales and processes: the international and national versus the local. The local politics of urban change in an east German city in the period after reunification question this divide. The ‘pathways’ approach to post-socialist transitions is utilized to illustrate how reunification is contested as much in neighbourhood restructuring and actions in response to incoming capital and the dominance of western legalpolitical norms as it is in national or international discourses and practices. Assumed divisions between East and West, professional and lay, and local and national are questioned.  相似文献