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521.
Evaluating and implementing social–ecological systems: A comprehensive approach to sustainable fisheries 下载免费PDF全文
Robert L. Stephenson Stacey Paul Melanie Wiber Eric Angel Ashleen J. Benson Anthony Charles Omer Chouinard Marc Clemens Dan Edwards Paul Foley Lindsay Jennings Owen Jones Dan Lane Jim McIsaac Claire Mussells Barbara Neis Bethany Nordstrom Courtenay Parlee Evelyn Pinkerton Mark Saunders Kevin Squires U. Rashid Sumaila 《Fish and Fisheries》2018,19(5):853-873
Fisheries sustainability is recognized to have four pillars: ecological, economic, social (including cultural) and institutional (or governance). Although international agreements, and legislation in many jurisdictions, call for implementation of all four pillars of sustainability, the social, economic and institutional aspects (i.e., the “human dimensions”) have not been comprehensively and collectively addressed to date. This study describes a framework for comprehensive fisheries evaluation developed by the Canadian Fisheries Research Network (CFRN) that articulates the full spectrum of ecological, economic, social and institutional objectives required under international agreements, together with candidate performance indicators for sustainable fisheries. The CFRN framework is aimed at practical fisheries evaluation and management and has a relatively balanced distribution of elements across the four pillars of sustainability relative to 10 alternative management decision support tools and indicator scorecards, which are heavily focused on ecological and economic aspects. The CFRN framework has five immediate uses: (a) It can serve as a logic frame for defining management objectives; (b) it can be used to define alternate management options to achieve given objectives; (c) it can serve as a tool for comparing management scenarios/options in decision support frameworks; (d) it can be employed to create a report card for comprehensive fisheries management evaluation; and (e) it is a tool for practical implementation of an integrated social–ecological system approach. 相似文献
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Radius and ulna fracture repair with the IMEX miniature circular external skeletal fixation system in 37 small and toy breed dogs: A retrospective study 下载免费PDF全文
524.
Magnetic resonance imaging versus computed tomography to plan hemilaminectomies in chondrodystrophic dogs with intervertebral disc extrusion 下载免费PDF全文
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Heather L. Matthees Yangbo He Rachel K. Owen David Hopkins Bob Deutsch John Lee 《Communications in Soil Science and Plant Analysis》2017,48(18):2148-2154
Since 1954, the electrical conductivity of the saturated paste extract (ECe) has been the preferred index for soil salinity. Based on this value, remediation strategies were developed and widely used but this approach is time consuming and not routinely offered by many soil testing facilities. However, many laboratories determine the EC1:1 value of a 1:1 soil to solution ratio extract. The objective of this study was to identify the relationship between ECe and EC1:1 and determine if EC1:1 can be used as a proxy in the northern Great Plains for ECe. Samples were collected across five studies and from AGVISE Laboratory. The samples were analyzed for EC1:1 and ECe. The relationship between the ECe and EC1:1 showed that soil parent materials need to be considered in the conversion of EC1:1 values to ECe values. A failure to consider parent materials in this conversion may have short and long-term sustainability ramifications. 相似文献
527.
The metabolizable energy (ME) content, digestibility in vivo and chemical composition of fermented and urea-treated whole crop wheat (WCW) forage harvested were measured at different maturities. Over 2 years, twenty-four wheat forages (cv. Slepjner, Hussar and Cadenza) were harvested at 376, 516 and 632 g dry matter (DM) kg−1 in Year 1 and 341, 467 and 544 g DM kg−1 in Year 2 (Cuts 1, 2 and 3 respectively). Forages were conserved in 200−-ι barrels with or without a formic acid-based additive and with urea in Cuts 2 and 3 (20 or 40 g kg−1 DM). Chemical compositions, digestibility in vivo and energy losses in faeces, urine and methane were measured in wethers fed 12 g DM kg−1 live weight. Respective ranges in pH, crude protein, water-soluble carbohydrates, starch and neutral detergent fibre plus amylase (NDFA) contents were 3·8–8·5, 89–394, 2–43, 23–424 and 306–655 g kg−1 DM. ME content, digestible organic matter content (DOMD) and digestibilities of starch and NDFA ranged between 8·4 and 15·7 MJ kg−1 DM, 558 and 708 g kg−1 DM, 0·901 and 0·999 and 0·362 and 0·693 respectively. Predicted methane energy losses were poorly correlated with measured values ( r 2 < 0·45) in both years, but this accounted for less than 0.1 MJ ME kg−1 DM. Significant ( P < 0.05) effects of maturity on the ME/DOMD ratio were observed and ascribed to differences in the extent of fermentation. Therefore, treatment application and maturity exert considerable influence on the ME content of WCW. 相似文献
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Jessica Jamuna Buss Kathryn Helen Wiltshire James Owen Harris Jason Elliot Tanner Marty Robert Deveney 《Journal of fish diseases》2020,43(3):359-369
Bonamia spp. cause epizootics in oysters worldwide. In southern Australia, Bonamia exitiosa Hine, Cochennac and Berthe, 2001 threatens aquaculture of Ostrea angasi Sowerby, 1871. Bonamia spp. infections can display strong seasonality, but seasonal dynamics of B. exitiosa–O. angasi are unknown. Ostrea angasi naïve to B. exitiosa infection were stocked onto farms in three growing regions, and B. exitiosa was monitored seasonally for one year. Environmental parameters we measured did not correlate with B. exitiosa prevalence or infection intensities. Extreme temperatures suggest O. angasi culture systems need development. Bonamia exitiosa prevalence increased over time. After three months, O. angasi had B. exitiosa prevalence of 0.08–0.4, and after one year, the prevalence was 0.57–0.88. At some sites, O. angasi had >0.5 B. exitiosa prevalence in >6 months, but at other sites, >9 months passed before prevalence was >0.5. Bonamia exitiosa infection intensities were low with no seasonal pattern but were affected by the interaction of site, season and oyster meat:shell ratio. Understanding infection and initiating a breeding programme for resistance would provide benefits for O. angasi industry expansion. 相似文献
530.
Ryan C. Hamberg Ramawatar Yadav Philip M Dixon Mark A. Licht Micheal DK Owen 《Pest management science》2023,79(12):4819-4827