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Can We Distinguish Acoustically Between Vendace Stock and Stickleback Stock in Lake Pluszne?
CAN WE DISTINGUISH ACOUSTICALLY BETWEEN VENDACE STOCK AND STICKLEBACK STOCK IN LAKE PLUSZNE? LECH DOROSZCZYK1, BRONISŁAW DŁUGOSZEWSKI1, MAŁGORZATA 2 GODLEWSKA 1 Stanisław Sakowicz Inland Fisheries Institute Oczapowskiego 10, 10-719 Olsztyn, Poland [email protected] 2International Institute of the Polish Academy of Sciences, European Regional Centre for Ecohydrology under auspices of UNESCO Tylna 3, 90-364 Łódź, Poland [email protected] Hydroacoustical monitoring of vendace stocks in lake Pluszne is performed regularly since 90-ties. However, in 2009 the lack of oxygen below the thermocline prevented fish to occupy the hypolimnion, which is its natural habitat. This led to a mixture of vendace and other fish species above the thermocline. The trawl catches accompanying hydroacoustical studies have contained exclusively vendace and stickleback. Investigation of TS have shown two-pick distributions, one corresponding to the size of vendace and one smaller. The two fish species were separated by thresholding. The maps of fish spatial distributions confirmed that vendace was present only in the deepest part of the lake, which is typical for this part of a year, while the other fish were distributed over the whole lake area. The worsening of environmental conditions in Lake Pluszne (increase of eutrophication) leads to declining vendace population. INTRODUCTION Over the past few decades, hydroacoustics has become increasingly important to the assessment of fish populations [1]. Fish stock assessment in inland waters is necessary for both: fisheries management and ecological environmental assessments, as a result of EU Water Framework Directive (WFD) requirements [2]. A wide range of sampling techniques have been developed for the assessment of fish populations in lakes and reservoirs including trawling, gill nets, electrofishing, etc. -
On the Spatial and Temporal Variability of Upwelling in the Southern
University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School 1-1-2012 On the spatial and temporal variability of upwelling in the southern Caribbean Sea and its influence on the ecology of phytoplankton and of the Spanish sardine (Sardinella aurita) Digna Tibisay Rueda-Roa University of South Florida, [email protected] Follow this and additional works at: https://scholarcommons.usf.edu/etd Part of the American Studies Commons, Oceanography Commons, Other Earth Sciences Commons, and the Other Oceanography and Atmospheric Sciences and Meteorology Commons Scholar Commons Citation Rueda-Roa, Digna Tibisay, "On the spatial and temporal variability of upwelling in the southern Caribbean Sea and its influence on the ecology of phytoplankton and of the Spanish sardine (Sardinella aurita)" (2012). Graduate Theses and Dissertations. https://scholarcommons.usf.edu/etd/4217 This Dissertation is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. On the spatial and temporal variability of upwelling in the southern Caribbean Sea and its influence on the ecology of phytoplankton and of the Spanish sardine (Sardinella aurita) by Digna T. Rueda-Roa A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy College of Marine Science University of South Florida Major Professor: Frank E. Muller-Karger, Ph.D. Mark Luther, Ph.D. Ernst Peebles, Ph.D. David Hollander, Ph.D. Eduardo Klein, Ph.D. Jeremy Mendoza, Ph.D. -
Velocity Mapping in the Lower Congo River: a First Look at the Unique Bathymetry and Hydrodynamics of Bulu Reach, West Central Africa
Velocity Mapping in the Lower Congo River: A First Look at the Unique Bathymetry and Hydrodynamics of Bulu Reach, West Central Africa P.R. Jackson U.S. Geological Survey, Illinois Water Science Center, Urbana, IL, USA K.A. Oberg U.S. Geological Survey, Office of Surface Water, Urbana, IL, USA N. Gardiner American Museum of Natural History, New York, NY, USA J. Shelton U.S. Geological Survey, South Carolina Water Science Center, Columbia, SC, USA ABSTRACT: The lower Congo River is one of the deepest, most powerful, and most biologically diverse stretches of river on Earth. The river’s 270 m decent from Malebo Pool though the gorges of the Crystal Mountains to the Atlantic Ocean (498 km downstream) is riddled with rapids, cataracts, and deep pools. Much of the lower Congo is a mystery from a hydraulics perspective. However, this stretch of the river is a hotbed for biologists who are documenting evolution in action within the diverse, but isolated, fish popula- tions. Biologists theorize that isolation of fish populations within the lower Congo is due to barriers pre- sented by flow structure and bathymetry. To investigate this theory, scientists from the U.S. Geological Sur- vey and American Museum of Natural History teamed up with an expedition crew from National Geographic in 2008 to map flow velocity and bathymetry within target reaches in the lower Congo River using acoustic Doppler current profilers (ADCPs) and echo sounders. Simultaneous biological and water quality sampling was also completed. This paper presents some preliminary results from this expedition, specifically with re- gard to the velocity structure and bathymetry. -
Implementation of Hydroacoustic for a Rapid Assessment of Fish Spatial
Acta Limnologica Brasiliensia, 2013, vol. 25, no. 1, p. 91-98 http://dx.doi.org/10.1590/S2179-975X2013000100010 Implementation of hydroacoustic for a rapid assessment of fish spatial distribution at a Brazilian Lake - Lagoa Santa, MG Aplicação do método hidroacústico na avaliação rápida da distribuição espacial de peixes em um Lago Brasileiro – Lagoa Santa, Minas Gerais José Fernandes Bezerra-Neto1, Ludmila Silva Brighenti 2 and Ricardo Motta Pinto-Coelho3 1Laboratório de Ecologia e Conservação, Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais – UFMG, CEP 31270-901, Belo Horizonte, MG, Brazil e-mail: [email protected] 2Programa de Pós-graduação em Ecologia, Conservação e Manejo da Vida Silvestre, Universidade Federal de Minas Gerais – UFMG, CEP 31270-901, Belo Horizonte, MG, Brazil e-mail: [email protected] 3Laboratório de Gestão Ambiental de Reservatórios Tropicais, Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais – UFMG, CP 486, CEP 31270-901, Belo Horizonte, MG, Brazil e-mail: [email protected] Abstract: Aim: To study the distribution, structure, size and density of fish in the karst lake: Lagoa Central (Lagoa Santa, MG - surface area: 1.7 km2; mean depth: 4.0 m; and maximum depth: 7.3 m). Methods: The hydroacoustic method with vertical beaming was applied, using the echosounder Biosonics DT-X with a split-beam transducer of 200 kHz. The analysis of the acoustic data was performed with the software Visual Analyzer (Biosonics Inc.). Thematic maps of density echoes associated with fish, estimated by the technique of echo-integration, were made using the kriging interpolation. -
A Parametric Analysis and Sensitivity Study of the Acoustic Propagation for Renewable Energy
OCS Study BOEM 2020-011 A Parametric Analysis and Sensitivity Study of the Acoustic Propagation for Renewable Energy US Department of the Interior Bureau of Ocean Energy Management Office of Renewable Energy Programs OCS Study BOEM 2020-011 A Parametric Analysis and Sensitivity Study of the Acoustic Propagation for Renewable Energy Sources 10 February 2020 Authors: Kevin D. Heaney, Michael A. Ainslie, Michele B. Halvorsen, Kerri D. Seger, Roel A.J. Müller, Marten J.J. Nijhof, Tristan Lippert Prepared under BOEM Award M17PD00003 Submitted by: CSA Ocean Sciences Inc. 8502 SW Kansas Avenue Stuart, Florida 34997 Telephone: 772-219-3000 US Department of the Interior Bureau of Ocean Energy Management Office of Renewable Energy Programs DISCLAIMER Study concept, oversight, and funding were provided by the U.S. Department of the Interior, Bureau of Ocean Energy Management (BOEM), Environmental Studies Program, Washington, D.C., under Contract Number M15PC00011. This report has been technically reviewed by BOEM, and it has been approved for publication. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the opinions or policies of the U.S. Government, nor does mention of trade names or commercial products constitute endorsement or recommendation for use. REPORT AVAILABILITY To download a PDF file of this report, go to the U.S. Department of the Interior, Bureau of Ocean Energy Management Data and Information Systems webpage (http://www.boem.gov/Environmental-Studies- EnvData/), click on the link for the Environmental Studies Program Information System (ESPIS), and search on 2020-011. The report is also available at the National Technical Reports Library at https://ntrl.ntis.gov/NTRL/. -
A Review on Deep Learning-Based Approaches for Automatic Sonar Target Recognition
electronics Review A Review on Deep Learning-Based Approaches for Automatic Sonar Target Recognition Dhiraj Neupane and Jongwon Seok * Department of Information and Communication Engineering, Changwon National University, Changwon-si, Gyeongsangnam-do 51140, Korea; [email protected] * Correspondence: [email protected] Received: 13 October 2020; Accepted: 19 November 2020; Published: 22 November 2020 Abstract: Underwater acoustics has been implemented mostly in the field of sound navigation and ranging (SONAR) procedures for submarine communication, the examination of maritime assets and environment surveying, target and object recognition, and measurement and study of acoustic sources in the underwater atmosphere. With the rapid development in science and technology, the advancement in sonar systems has increased, resulting in a decrement in underwater casualties. The sonar signal processing and automatic target recognition using sonar signals or imagery is itself a challenging process. Meanwhile, highly advanced data-driven machine-learning and deep learning-based methods are being implemented for acquiring several types of information from underwater sound data. This paper reviews the recent sonar automatic target recognition, tracking, or detection works using deep learning algorithms. A thorough study of the available works is done, and the operating procedure, results, and other necessary details regarding the data acquisition process, the dataset used, and the information regarding hyper-parameters is presented in -
The Effects of Fall Coldfront Passages on the Nekton Community in a Tidal Creek in Port Fourchon, LA, As Monitored by Hydroacoustics David J
Louisiana State University LSU Digital Commons LSU Master's Theses Graduate School 2002 The effects of fall coldfront passages on the nekton community in a tidal creek in Port Fourchon, LA, as monitored by hydroacoustics David J. Harmon Louisiana State University and Agricultural and Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_theses Part of the Oceanography and Atmospheric Sciences and Meteorology Commons Recommended Citation Harmon, David J., "The effects of fall coldfront passages on the nekton community in a tidal creek in Port Fourchon, LA, as monitored by hydroacoustics" (2002). LSU Master's Theses. 2890. https://digitalcommons.lsu.edu/gradschool_theses/2890 This Thesis is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Master's Theses by an authorized graduate school editor of LSU Digital Commons. For more information, please contact [email protected]. THE EFFECTS OF FALL COLDFRONT PASSAGES ON THE NEKTON COMMUNITY IN A TIDAL CREEK IN PORT FOURCHON, LA, AS MONITORED BY HYDROACOUSTICS A Thesis Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Master of Science in The Department of Oceanography and Coastal Studies by David J. Harmon B.S., University of South Carolina, 1999 August, 2002 Acknowledgements I wish to thank Dr. Charles Wilson for his endless help and guidance as my major professor, Drs. Conrad Lamon and Richard Shaw for being excellent committee members. Mark Miller for helping design and implement the new deployment system, Wilton Delaune for field assistance, Jim Dawson and John Hedgepeth for hydroacoustic expertise and all the faculty, graduates students and friends who helped along the way. -
Implementation of Adaptive and Synthetic-Aperture Processing Schemes in Integrated Active–Passive Sonar Systems
Implementation of Adaptive and Synthetic-Aperture Processing Schemes in Integrated Active–Passive Sonar Systems STERGIOS STERGIOPOULOS, SENIOR MEMBER, IEEE Progress in the implementation of state-of-the-art signal- NOMENCLATURE processing schemes in sonar systems is limited mainly by the moderate advancements made in sonar computing architectures Complex conjugate transpose operator. and the lack of operational evaluation of the advanced processing Power spectral density of signal . schemes. Until recently, matrix-based processing techniques, such as adaptive and synthetic-aperture processing, could not AG Array gain. be efficiently implemented in the current type of sonar systems, Small positive number designed to main- even though it is widely believed that they have advantages that can address the requirements associated with the difficult tain stability in normalized least mean operational problems that next-generation sonars will have to square adaptive algorithm. solve. Interestingly, adaptive and synthetic-aperture techniques Narrow-band beam-power pattern of may be viewed by other disciplines as conventional schemes. For a line array expressed by the sonar technology discipline, however, they are considered as advanced schemes because of the very limited progress that has . been made in their implementation in sonar systems. Broad-band beam-power pattern of a line This paper is intended to address issues of implementation of array steered at direction . advanced processing schemes in sonar systems and also to serve as a brief overview to the principles and applications of advanced Beams for conventional or adaptive sonar signal processing. The main development reported in beam formers or plane wave this paper deals with the definition of a generic beam-forming response of a line array steered structure that allows the implementation of nonconventional at direction and expressed by signal-processing techniques in integrated active–passive sonar . -
Effects of Sound on Fish
Effects of Sound on Fish by Mardi C. Hastings,1 Ph.D. & Arthur N. Popper,1 Ph.D. Subconsultants to Jones & Stokes Under California Department of Transportation Contract No. 43A0139, Task Order 1 Funding Provided by the California Department of Transportation Prime Contractor: Jones & Stokes 2600 V Street Sacramento, CA 95818 January 28, 2005 August 23, 2005 (Revised Appendix B) 1 Any opinions or positions expressed in this report are those of the authors' and do not necessarily represent the opinions or positions of their employers, the State of California, the State of Maryland, or the United States Government 1 Table of Contents Summary____________________________________________________________________ 4 A. Effects of Pile-Driving Sound on Fish____________________________________________ 4 B. Areas of Uncertainty and Studies Needed ________________________________________ 5 Table 1: Outline of studies to investigate pile driving and its effects on fishes._______________________6 C. Terminology ________________________________________________________________ 7 I. Introduction _______________________________________________________________ 8 II. Characterization of Pile Driving Sound and Its Effect on Fishes ___________________ 10 A. Overview of Pile Driving Sound _______________________________________________ 10 B. Comparison of Pile Driving Sound Waveforms with an Ideal Impulse Wave __________ 12 C. Overview of Results from Recent Pile Driving Studies_____________________________ 13 1. Caltrans (2001)______________________________________________________________________13 -
Compressive Underwater Sonar Imaging with Synthetic Aperture Processing
remote sensing Article Compressive Underwater Sonar Imaging with Synthetic Aperture Processing Ha-min Choi 1 , Hae-sang Yang 1 and Woo-jae Seong 1,2,* 1 Department of Naval Architecture and Ocean Engineering, Seoul National University, Seoul 08826, Korea; [email protected] (H.-m.C.); [email protected] (H.-s.Y.) 2 Research Institute of Marine Systems Engineering, Seoul National University, Seoul 08826, Korea * Correspondence: [email protected]; Tel.: +82-2-880-7332 Abstract: Synthetic aperture sonar (SAS) is a technique that acquires an underwater image by synthesizing the signal received by the sonar as it moves. By forming a synthetic aperture, the sonar overcomes physical limitations and shows superior resolution when compared with use of a side-scan sonar, which is another technique for obtaining underwater images. Conventional SAS algorithms require a high concentration of sampling in the time and space domains according to Nyquist theory. Because conventional SAS algorithms go through matched filtering, side lobes are generated, resulting in deterioration of imaging performance. To overcome the shortcomings of conventional SAS algorithms, such as the low imaging performance and the requirement for high-level sampling, this paper proposes SAS algorithms applying compressive sensing (CS). SAS imaging algorithms applying CS were formulated for a single sensor and uniform line array and were verified through simulation and experimental data. The simulation showed better resolution than the !-k algorithms, one of the representative conventional SAS algorithms, with minimal performance degradation by side lobes. The experimental data confirmed that the proposed method is superior and robust with respect to sensor loss. -
Underwater Acoustics and Its Applications: a Historical Review
Proceedings of the 2nd EAA International Symposium on Hydroacoustics 24-27 May 1999, Gdańsk-Jurata POLAND Underwater Acoustics and its Applications. A Historical Review. Leif Bjerna, Irina Bjerne Department of Industrial Acoustics, Technical University of Denmark, Building 425, DK-2800 Lyngby, Denmark. l. Introduction 2. Studies of underwater acoustics before World War! Underwater acoustics is one of the fastest grow- ing fields of research in acoustics. The number of The Greek philosopher,. Aristotle (384 - 322 publications per year in underwater acoustics is still B.C.) may have been one of the first to note that increasing. The relationship to other fields of im- sound could be heard in water as well as in air. In portance for science and technology like oceanogra- 1490 the Italian, Leonardo da Vinci (1452 - 1519) phy, seismology and fishery is becoming more close. wrote in his notebook: "if you cause your ship to Every year billions of dollars are spent on the use of stop, and place the head of a long tube in the water underwater acoustics by the mineral industry (oil and place the other extremity to your ear, you will and solid mineral exploration in the sea), by the food hear ships at great distances". Of course, the back- industry (fishing), by the transportation and recrea- ground noise of lakes and seas was much lower in tion industries (navigation and safety devices) and his days than now, when all kinds of ships pollute by the worlds navies (undersea warfare). A great the seas with noise. About one hundred years later, number of industrial companies are developing and Francis Bacon in Narural History supported the manufacturing instrurnents and devices for under- idea, that water is the principal medium by which water acoustics, including for instance instruments sounds originating therein reach a human observer for inspection and mapping of the seabed, for un- standing nearby. -
Ocean Acoustic Tomography
Radiating Wideband Sonar Pulses with Resonant Sandwich Transducers by Designing the Driving Voltage Waveform P. Cobo, C. Ranz, and M. Siguero Instituto de Acústica, CSIC. Serrano 144. 28006 Madrid. SPAIN A technique to radiate short length, high resolution, pulses with conventional piezoelectric transducers is described. It consists on designing the driving voltage waveform so that the radiated pulse has a zero-phase cosine-magnitude spectrum compatible with the natural frequency response of the transducer. According to Berkhout [1], zero-phase cosine-magnitude pulses have the minimum length, maximum resolution, within a prescribed frequency band. When applied to a 9 kHz sandwich transducer, this technique decreases the pulse length from 1 ms to 0.13 ms, increases the bandwidth from 1.4 kHz to 11.25 kHz, and lowers the Q factor from 6.2 to 1.23, at the cost of 33% of amplitude loss. INTRODUCTION H *( f ) X e ( f ) Ye ( f ) , (2) H( f ) 2 p 2 An underwater transducer is driven usually by a tone-burst. However, Winter et al. [2] and Mazzola 2 and Raff [3] showed that is possible to use Fourier where p is a regularisation constant, and * denotes techniques to find the electrical driving function so conjugate complex. Therefore, the electrical function that the transducer radiates a prescribed acoustic which must be synthesized is waveform. Holly et al. [4] reported that a transducer driven with a shaped function responded in two '$ '4 ]1 ]1 H *( f ) octaves, with an amplitude loss of 15 dB. xe (t) X e ( f ) %Ye ( f ) 5 (3) 2 2 Cobo [5] applied this technique to synthesize zero- &' H( f ) p 6' phase cosine-magnitude, gaussian, and bionic pulses, with a conventional sandwich transducer.