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排序方式: 共有421条查询结果,搜索用时 191 毫秒
341.
Marine current energy converters such as tidal and riverine turbines have the potential to provide reliable, clean power. The risk of collision of fishes with marine energy turbines is not yet well understood, in part due to the challenges associated with observing fish at turbine sites. Turbidity and light availability can limit the effectiveness of optical sensors like video cameras, motivating the use of acoustic cameras for this task. However, challenges persist in collecting and interpreting data acquired from acoustic cameras. Given the limited number of turbine deployments to date, it is prudent to draw on the application of acoustic cameras to monitor fish in other scenarios. This article synthesizes their use for other fisheries applications to inform best practices and set realistic expectations for the results of acoustic camera monitoring at turbine sites. We discuss six key tasks performed with acoustic cameras: detecting objects, identifying objects as fish, counting fish, measuring fish, classifying fish taxonomically and analysing fish behavior. Specific challenges to monitoring fish at turbine sites are discussed. This article is intended to serve as a reference for researchers, regulators and marine energy developers on effective use of acoustic cameras to monitor fish at turbine sites. The studies detailed in this article provide evidence that, in some scenarios, acoustic cameras can be used to inform the risk of fish collision with marine energy turbines but doing so requires careful study design and data processing. 相似文献
342.
Rowan Trebilco Rosemary Gales Emma Lawrence Rachael Alderman Graham Robertson G. Barry Baker 《水产资源保护:海洋与淡水生态系统》2010,20(5):531-542
- 1. Seabirds killed incidentally in Australia's eastern tuna and billfish (ETBF) longline fishery between September 2001 and June 2006 were examined to evaluate species composition and to relate, where possible, capture events to operational and environmental factors.
- 2. During this period 2.129 million hooks on 2202 shots were observed, and 369 birds were reported killed. The majority (78%) of these were flesh‐footed shearwaters (Puffinus carniepes), 53% of which were male and 44% female. Smaller numbers of medium to large sized albatrosses (Diomedeidae, predominantly female) and other shearwaters (Puffinus spp.) and petrels (Pterodroma spp.) dominated the remainder of the bycatch.
- 3. Of the 369 birds reported taken as bycatch, 280 were available for necropsy, and species identifications performed in situ by observers were assessed. While observer identifications were generally correct for common species, performance was poor for less common ones.
- 4. The geographical location (latitude) of shots, season, time of day at which shots were set, and bait type and life status (dead or alive) influenced the seabird bycatch rate. The majority of captures (87% overall) occurred between 30 and 35°S, with bycatch being lowest in winter, and remaining at similar levels across the other seasons.
- 5. The use of live fish bait was generally associated with increased captures of both seabirds overall, and flesh‐footed shearwaters in particular. Copyright © 2010 John Wiley & Sons, Ltd.
343.
344.
Truchy Amélie Göthe Emma Angeler David G. Ecke Frauke Sponseller Ryan A. Bundschuh Mirco Johnson Richard K. McKie Brendan G. 《Landscape Ecology》2019,34(10):2371-2384
Landscape Ecology - Community composition, environmental variation, and spatial structuring can influence ecosystem functioning, and ecosystem service delivery. While the role of space in... 相似文献
345.
Laurent Philippot Cristina Abbate Antonio Bispo Thierry Chesnot Sara Hallin Philippe Lemanceau Kristina Lindström Pascal Pandard Esperanza Romero Michael Schloter Pascal Simonet Kornelia Smalla Berndt-Michael Wilke Imes Petric Fabrice Martin-Laurent 《Journal of Soils and Sediments》2010,10(7):1344-1345
346.
The direct, by-product-free conversion of basic feedstocks to products of medicinal and agricultural relevance is a broad goal of chemical research. Butadiene is a product of petroleum cracking and is produced on an enormous scale (about 12 × 10(6) metric tons annually). Here, with the use of a ruthenium catalyst modified by a chiral phosphate counterion, we report the direct redox-triggered carbon-carbon coupling of alcohols and butadiene to form products of carbonyl crotylation with high levels of anti-diastereoselectivity and enantioselectivity in the absence of stoichiometric by-products. 相似文献
347.
Nicolas P Mäder U Dervyn E Rochat T Leduc A Pigeonneau N Bidnenko E Marchadier E Hoebeke M Aymerich S Becher D Bisicchia P Botella E Delumeau O Doherty G Denham EL Fogg MJ Fromion V Goelzer A Hansen A Härtig E Harwood CR Homuth G Jarmer H Jules M Klipp E Le Chat L Lecointe F Lewis P Liebermeister W March A Mars RA Nannapaneni P Noone D Pohl S Rinn B Rügheimer F Sappa PK Samson F Schaffer M Schwikowski B Steil L Stülke J Wiegert T Devine KM Wilkinson AJ van Dijl JM Hecker M Völker U Bessières P 《Science (New York, N.Y.)》2012,335(6072):1103-1106
348.
This randomised, blinded, cross-over study investigated the ease of oral transmucosal administration of two formulations of buprenorphine using glucose as a control in 12 cats. The cats received three treatments: buprenorphine multi-dose, buprenorphine and the equivalent volume of glucose 5%. Ease of treatment administration, observation of swallowing, changes in pupil size, sedation, salivation, vomiting, behaviour and food intake were assessed. The data were analysed using MLwiN and multi-level modelling. Ease of administration of buprenorphine multi-dose was statistically different from glucose (P <0.001), and the administration of all treatments became easier over the study periods. Swallowing was not statistically different between groups (P >0.05). Mydriasis was evident after the administration of both formulations of buprenorphine. Sedation, salivation, vomiting, behavioural changes or in-appetence were not observed after any treatment. Cats tolerated oral transmucosal administration of glucose better than buprenorphine multi-dose, while buprenorphine administration was tolerated as well as glucose. 相似文献
349.
Bortolami E Love EJ Harcourt-Brown TR Higgs P Robinson K 《Veterinary anaesthesia and analgesia》2012,39(4):446-447
350.
Jo Hockenhull Emma Creighton 《Journal of Veterinary Behavior: Clinical Applications and Research》2012,7(5):305-310
The inability of owners to recognize patterns behind the seemingly disparate or random behavior problems expressed by their horse has major welfare implications. Principal components analysis has been successfully used to explore relationships between individual behavior problems in dogs, and it may be a valuable tool in recognizing relationships between problem behaviors in horses. Here, we report how principal components analysis has been used to identify relationships underlying individual behavior problems in horses using data generated from a large-scale Internet survey of United Kingdom leisure horses. Horse-level data on the performance of 44 individual behavior problems, encompassing stable-related and handling behavior problems, prefeeding behavior problems, and ridden behavior problems, were reduced to 12 behavior problem components. Each component was composed of groups of behavior problems that may share a common underlying etiology. These findings demonstrate the value of statistical techniques in identifying associations between apparently random behavior problems. Recognizing relationships between individual problems may prompt owners to take earlier action to resolve them, thereby improving their horse’s welfare. 相似文献