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Functional Responses of Fish Communities to Environmental Gradients in the North Sea, Eastern English Channel, and Bay of Somme Matthew Mclean
Functional responses of fish communities to environmental gradients in the North Sea, Eastern English Channel, and Bay of Somme Matthew Mclean To cite this version: Matthew Mclean. Functional responses of fish communities to environmental gradients in the North Sea, Eastern English Channel, and Bay of Somme. Ecology, environment. Université du Littoral Côte d’Opale, 2019. English. NNT : 2019DUNK0532. tel-02384271 HAL Id: tel-02384271 https://tel.archives-ouvertes.fr/tel-02384271 Submitted on 28 Nov 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Thèse de doctorat de L’Université du Littoral Côte d’Opale Ecole doctorale – Sciences de la Matière, du Rayonnement et de l’Environnement Pour obtenir le grade de Docteur en sciences et technologies Spécialité : Géosciences, Écologie, Paléontologie, Océanographie Discipline : BIOLOGIE, MEDECINE ET SANTE – Physiologie, biologie des organismes, populations, interactions Functional responses of fish communities to environmental gradients in the North Sea, Eastern English Channel, and Bay of Somme Réponses fonctionnelles des communautés de poissons aux gradients environnementaux en mer du Nord, Manche orientale, et baie de Somme Présentée et soutenue par Matthew MCLEAN Le 13 septembre 2019 devant le jury composé de : Valeriano PARRAVICINI Maître de Conférences à l’EPHE Président Raul PRIMICERIO Professeur à l’Université de Tromsø Rapporteur Camille ALBOUY Cadre de Recherche à l’IFREMER Examinateur Maud MOUCHET Maître de Conférences au CESCO Examinateur Rita P. -
Dung Beetle Richness, Abundance, and Biomass Meghan Gabrielle Radtke Louisiana State University and Agricultural and Mechanical College, [email protected]
Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School 2006 Tropical Pyramids: Dung Beetle Richness, Abundance, and Biomass Meghan Gabrielle Radtke Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Recommended Citation Radtke, Meghan Gabrielle, "Tropical Pyramids: Dung Beetle Richness, Abundance, and Biomass" (2006). LSU Doctoral Dissertations. 364. https://digitalcommons.lsu.edu/gradschool_dissertations/364 This Dissertation 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 Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. TROPICAL PYRAMIDS: DUNG BEETLE RICHNESS, ABUNDANCE, AND BIOMASS A Dissertation 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 Doctor of Philosophy in The Department of Biological Sciences by Meghan Gabrielle Radtke B.S., Arizona State University, 2001 May 2007 ACKNOWLEDGEMENTS I would like to thank my advisor, Dr. G. Bruce Williamson, and my committee members, Dr. Chris Carlton, Dr. Jay Geaghan, Dr. Kyle Harms, and Dr. Dorothy Prowell for their help and guidance in my research project. Dr. Claudio Ruy opened his laboratory to me during my stay in Brazil and collaborated with me on my project. Thanks go to my field assistants, Joshua Dyke, Christena Gazave, Jeremy Gerald, Gabriela Lopez, and Fernando Pinto, and to Alejandro Lopera for assisting me with Ecuadorian specimen identifications. I am grateful to Victoria Mosely-Bayless and the Louisiana State Arthropod Museum for allowing me work space and access to specimens. -
A Quantitative Study of Advanced Encryption Standard Performance
United States Military Academy USMA Digital Commons West Point ETD 12-2018 A Quantitative Study of Advanced Encryption Standard Performance as it Relates to Cryptographic Attack Feasibility Daniel Hawthorne United States Military Academy, [email protected] Follow this and additional works at: https://digitalcommons.usmalibrary.org/faculty_etd Part of the Information Security Commons Recommended Citation Hawthorne, Daniel, "A Quantitative Study of Advanced Encryption Standard Performance as it Relates to Cryptographic Attack Feasibility" (2018). West Point ETD. 9. https://digitalcommons.usmalibrary.org/faculty_etd/9 This Doctoral Dissertation is brought to you for free and open access by USMA Digital Commons. It has been accepted for inclusion in West Point ETD by an authorized administrator of USMA Digital Commons. For more information, please contact [email protected]. A QUANTITATIVE STUDY OF ADVANCED ENCRYPTION STANDARD PERFORMANCE AS IT RELATES TO CRYPTOGRAPHIC ATTACK FEASIBILITY A Dissertation Presented in Partial Fulfillment of the Requirements for the Degree of Doctor of Computer Science By Daniel Stephen Hawthorne Colorado Technical University December, 2018 Committee Dr. Richard Livingood, Ph.D., Chair Dr. Kelly Hughes, DCS, Committee Member Dr. James O. Webb, Ph.D., Committee Member December 17, 2018 © Daniel Stephen Hawthorne, 2018 1 Abstract The advanced encryption standard (AES) is the premier symmetric key cryptosystem in use today. Given its prevalence, the security provided by AES is of utmost importance. Technology is advancing at an incredible rate, in both capability and popularity, much faster than its rate of advancement in the late 1990s when AES was selected as the replacement standard for DES. Although the literature surrounding AES is robust, most studies fall into either theoretical or practical yet infeasible. -
Exploring Seagrass Ecosystems Distance Learning Module Grades 3-8
Exploring Seagrass Ecosystems Distance Learning Module Grades 3-8 Smithsonian Marine Ecosystems Exhibit Word Search: Seagrass Just like finding animals in an actual seagrass bed, finding words in this word search will be a little tricky! See if you can search and find all the words! Snapping Shrimp: A small species of burrowing shrimp. When they open and close their specialized claws, it sounds like a human's snap! Nursery: Many juvenile fish and invertebrates utilize this habitat as they grow. Seagrass provides complex protection from predators and many food sources. Turtle Grass: A thick bladed species of seagrass that is the preferred snack of Green Sea Turtles! Seagrasses are related to land plants. Nutrients: Many nutrients are important for seagrass habitats. The two most important are Nitrogen and Phosphorous. Mullet: An herbivorous fish that you can often see jumping or swimming in schools near the surface of the water in tidal estuaries. Brackish: Brackish water is a combination of both fresh water from rivers and salt water from the ocean. When these bodies of water meet and mix, we call it an estuary. Manatee Grass: A thin, and round bladed species of seagrass. Manatees can often be found grazing on this species. Oxygen: Did you know that as a byproduct of photosynthesis, seagrass is a huge producer of the oxygen we breath? Boxfish: These unique box-shaped fish are one of the juvenile species you can find in the seagrass beds. Sunlight: Sunlight is required for photosynthesis, the process where plants convert sunlight to food. Aerobic Zone: Depth to which oxygen diffuses down into the substrate. -
Consumption Impacts by Marine Mammals, Fish, and Seabirds on The
83 Consumption impacts by marine mammals, fish, and seabirds on the Gulf of Maine–Georges Bank Atlantic herring (Clupea harengus) complex during the years 1977–2002 W. J. Overholtz and J. S. Link Overholtz, W. J. and Link, J. S. 2007. Consumption impacts by marine mammals, fish, and seabirds on the Gulf of Maine–Georges Bank Atlantic herring (Clupea harengus) complex during the years 1977–2002. ICES Journal of Marine Science, 64: 83–96. A comprehensive study of the impact of predation during the years 1977–2002 on the Gulf of Maine–Georges Bank herring complex is presented. An uncertainty approach was used to model input variables such as predator stock size, daily ration, and diet composition. Statistical distributions were constructed on the basis of available data, producing informative and uninformative inputs for estimating herring consumption within an uncertainty framework. Consumption of herring by predators tracked herring abundance closely during the study period, as this important prey species recovered following an almost complete collapse during the late 1960s and 1970s. Annual consumption of Atlantic herring by four groups of predators, demersal fish, marine mammals, large pelagic fish, and seabirds, averaged just 58 000 t in the late 1970s, increased to 123 000 t between 1986 and 1989, 290 000 t between 1990 and 1994, and 310 000 t during the years 1998–2002. Demersal fish consumed the largest proportion of this total, followed by marine mammals, large pelagic fish, and seabirds. Sensitivity analyses suggest that future emphasis should be placed on collecting time-series of diet composition data for marine mammals, large pelagic fish, and seabirds, with additional monitoring focused on the abundance of seabirds and daily rations of all groups. -
Effects of Human Disturbance on Terrestrial Apex Predators
diversity Review Effects of Human Disturbance on Terrestrial Apex Predators Andrés Ordiz 1,2,* , Malin Aronsson 1,3, Jens Persson 1 , Ole-Gunnar Støen 4, Jon E. Swenson 2 and Jonas Kindberg 4,5 1 Grimsö Wildlife Research Station, Department of Ecology, Swedish University of Agricultural Sciences, SE-730 91 Riddarhyttan, Sweden; [email protected] (M.A.); [email protected] (J.P.) 2 Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Postbox 5003, NO-1432 Ås, Norway; [email protected] 3 Department of Zoology, Stockholm University, SE-10691 Stockholm, Sweden 4 Norwegian Institute for Nature Research, NO-7485 Trondheim, Norway; [email protected] (O.-G.S.); [email protected] (J.K.) 5 Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden * Correspondence: [email protected] Abstract: The effects of human disturbance spread over virtually all ecosystems and ecological communities on Earth. In this review, we focus on the effects of human disturbance on terrestrial apex predators. We summarize their ecological role in nature and how they respond to different sources of human disturbance. Apex predators control their prey and smaller predators numerically and via behavioral changes to avoid predation risk, which in turn can affect lower trophic levels. Crucially, reducing population numbers and triggering behavioral responses are also the effects that human disturbance causes to apex predators, which may in turn influence their ecological role. Some populations continue to be at the brink of extinction, but others are partially recovering former ranges, via natural recolonization and through reintroductions. -
Experimental Study of the Zooplankton Impact on the Trophic Structure of Phytoplankton and the Microbial Assemblages in a Temper
ARTICLE IN PRESS Limnologica 37 (2007) 88–99 www.elsevier.de/limno Experimental study of the zooplankton impact on the trophic structure of phytoplankton and the microbial assemblages in a temperate wetland (Argentina) Rodrigo Sinistroa,Ã, Marı´ a Laura Sa´ ncheza, Marı´ a Cristina Marinoneb, Irina Izaguirrea,c aDepartamento de Ecologı´a, Gene´tica y Evolucio´n, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, C1428EHA Buenos Aires, Argentina bDepartamento de Biodiversidad y Biologı´a Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, C1428EHA Buenos Aires, Argentina cConsejo Nacional de Investigaciones Cientı´ficas y Te´cnicas (CONICET), Argentina Received 7 July 2006; received in revised form 23 August 2006; accepted 1 September 2006 Abstract An experimental study using mesocosms was conducted in the main shallow lake of a temperate wetland (Otamendi Natural Reserve, Argentina) to analyse the impact of zooplankton on phytoplankton and the microbial assemblages. The lake is characterised by the presence of a fluctuating cover of floating macrophytes, whose shading effects shape the phytoplakton community and the ecosystem functioning, which was absent during the study period. The experiment was run in situ using polyethylene bags, comparing treatments with and without zooplankton. The cascade effect of zooplankton on phytoplankton and the lower levels of the microbial food web (ciliates, heterotrophic nanoflagellates (HNF) and picoplankton) were analysed. A significant zooplankton grazing on the nano-phytoplankton fraction (3–30 mm) was observed. Conversely, large algae (filamentous cyanobacteria, colonial chlorophytes and large diatoms) increased in all mesocosms until day 10, suggesting that they were not actively grazed by zooplankton during this period. -
Assessing Habitat Quality for Conservation Using an Integrated
Journal of Applied Ecology 2009, 46, 600–609 doi: 10.1111/j.1365-2664.2009.01634.x AssessingBlackwell Publishing Ltd habitat quality for conservation using an integrated occurrence-mortality model Alessandra Falcucci1*, Paolo Ciucci1, Luigi Maiorano1, Leonardo Gentile2 and Luigi Boitani1 1Department of Animal and Human Biology, Sapienza Università di Roma, Viale dell’Università 32, 00185 Rome, Italy and 2Servizio Veterinario, Ente Parco Nazionale d’Abruzzo Lazio e Molise, Viale S. Lucia, 67032 Pescasseroli (l’Aquila), Italy Summary 1. Habitat suitability models are usually produced using species presence or habitat selection, with- out taking into account the demographic performance of the population considered. These models cannot distinguish between sink and source habitats, causing problems especially for species with low reproductive rates and high susceptibility to low levels of mortality as in the case of the critically endangered Apennine brown bear Ursus arctos marsicanus. 2. We developed a spatial model based on bear presence (2544 locations) and mortality data (37 locations) used as proxies for demographic performance. We integrated an occurrence and a mortality-risk Ecological Niche Factor Analysis model into a final two-dimensional model that can be used to distinguish between attractive sink-like and source-like habitat. 3. Our integrated model indicates that a traditional habitat suitability model can provide misleading management and conservation indications, as 43% of the area suitable for the occurrence model is associated with high mortality risk. Areas of source-like habitat for the Apennine bears (highly elevated areas rich in beech forests, far from roads, and with low human density and cultivated fields) are still present, including outside the currently occupied range. -
Calculation and Use of Selectivity Coefficients of Feeding: Zooplankton Grazing *
Ecological Modelling, 7 (1979) 135--149 135 © Elsevier Scientific Publishing Company, Amsterdam -- Printed in The Netherlands CALCULATION AND USE OF SELECTIVITY COEFFICIENTS OF FEEDING: ZOOPLANKTON GRAZING * HENRY A. VANDERPLOEG and DONALD SCAVIA National Oceanic and Atmospheric Administration, Environmental Research Laboratories, Great Lakes Environmental Research Laboratory, Ann Arbor, Mich. 48104 (U.S.A.) (Received 8 June 1978; revised 27 September 1978) ABSTRACT Vanderploeg, H.A. and Scavia, D., 1979. Calculation and use of selectivity coefficients of feeding: zooplankton grazing. Ecol. Modelling, 7: 135--149. A straightforward method of calculating selectivity coefficients (Wii) of predation from raw data, mortality rates of prey, filtering rates, feeding rates and electivity indices is derived. Results from a comparison of selectivity coefficients for the copepod Diaptomus oregonensis grazing under a number of experimental conditions suggest that Wij's for size- selective feeding are invariant, a conclusion also supported by the leaky-sieve model. Recommendations are made on how to use Wij's in linear and nonlinear feeding constructs for zooplankton and other animals. INTRODUCTION Many recent aquatic ecosystem models have been designed to simulate seasonal succession of phytoplankton and zooplankton. In order to accom- plish this, the models have included several phytoplankton and zooplankton groups (Bloomfield et al., 1973; Park et al., 1974; Canale et al., 1976; Scavia et al., 1976a and b; Bierman, 1976). A main factor controlling successional change in both phytoplankton and zooplankton is zooplankton selective feeding (cf. Porter, 1977). Many field and laboratory studies have been carried out to quantify the selection process; however, the forms in which the data are reported are not immediately applicable to models. -
"Species Richness: Small Scale". In: Encyclopedia of Life Sciences (ELS)
Species Richness: Small Advanced article Scale Article Contents . Introduction Rebecca L Brown, Eastern Washington University, Cheney, Washington, USA . Factors that Affect Species Richness . Factors Affected by Species Richness Lee Anne Jacobs, University of North Carolina, Chapel Hill, North Carolina, USA . Conclusion Robert K Peet, University of North Carolina, Chapel Hill, North Carolina, USA doi: 10.1002/9780470015902.a0020488 Species richness, defined as the number of species per unit area, is perhaps the simplest measure of biodiversity. Understanding the factors that affect and are affected by small- scale species richness is fundamental to community ecology. Introduction diversity indices of Simpson and Shannon incorporate species abundances in addition to species richness and are The ability to measure biodiversity is critically important, intended to reflect the likelihood that two individuals taken given the soaring rates of species extinction and human at random are of the same species. However, they tend to alteration of natural habitats. Perhaps the simplest and de-emphasize uncommon species. most frequently used measure of biological diversity is Species richness measures are typically separated into species richness, the number of species per unit area. A vast measures of a, b and g diversity (Whittaker, 1972). a Di- amount of ecological research has been undertaken using versity (also referred to as local or site diversity) is nearly species richness as a measure to understand what affects, synonymous with small-scale species richness; it is meas- and what is affected by, biodiversity. At the small scale, ured at the local scale and consists of a count of species species richness is generally used as a measure of diversity within a relatively homogeneous area. -
Single Gene Locus Changes Perturb Complex Microbial Communities As Much As Apex Predator Loss
ARTICLE Received 5 Dec 2014 | Accepted 30 Jul 2015 | Published 10 Sep 2015 DOI: 10.1038/ncomms9235 OPEN Single gene locus changes perturb complex microbial communities as much as apex predator loss Deirdre McClean1,2, Luke McNally3,4, Letal I. Salzberg5, Kevin M. Devine5, Sam P. Brown6 & Ian Donohue1,2 Many bacterial species are highly social, adaptively shaping their local environment through the production of secreted molecules. This can, in turn, alter interaction strengths among species and modify community composition. However, the relative importance of such behaviours in determining the structure of complex communities is unknown. Here we show that single-locus changes affecting biofilm formation phenotypes in Bacillus subtilis modify community structure to the same extent as loss of an apex predator and even to a greater extent than loss of B. subtilis itself. These results, from experimentally manipulated multi- trophic microcosm assemblages, demonstrate that bacterial social traits are key modulators of the structure of their communities. Moreover, they show that intraspecific genetic varia- bility can be as important as strong trophic interactions in determining community dynamics. Microevolution may therefore be as important as species extinctions in shaping the response of microbial communities to environmental change. 1 Department of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin D2, Ireland. 2 Trinity Centre for Biodiversity Research, Trinity College Dublin, Dublin D2, Ireland. 3 Centre for Immunity, Infection and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK. 4 Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK. 5 Smurfit Institute of Genetics, School of Genetics and Microbiology, Trinity College Dublin, Dublin D2, Ireland. -
Master Thesis Development and Characteristics of Applied Ecology
1 Faculty of Applied Ecology and Agricultural Sciences Farina Sooth Master thesis Development and characteristics of applied ecology Master in Applied Ecology 2014 2 __________ _________________ _____________________ Date Place Signature I agree that this thesis is for loan in the library YES ☐ NO ☐ I agree that this thesis is open accessible in Brage YES ☐ NO ☐ 3 Abstract The science of applied ecology is lacking a general theory and a commonly acknowledged definition. Additionally, information about the development of applied ecology over the past years, the relation to other disciplines and the importance of applied ecology in different continents are scarce. This is problematic because applied ecology is confronted with growing problems and the society demands more and more that it fulfils its promise of solving practical problems related to the environment. In the past applied ecology regularly failed to keep this promise and is faced with the future challenge of eliminating this problem. Based on communication theory I assume that for a fruitful discussion about the future of applied ecology, the development and the understanding of ecology have to be clarified first to avoid to talk at cross. Therefore, I conducted different qualitative and quantitative content analyses based on material from books and papers dealing with the subject of applied ecology or related disciplines to find out how applied ecology developed over time and what is understood under the term applied ecology. I found out that applied ecology is a young and interdisciplinary oriented science. Its origin lays in the science of ecology and since the 1960s applied ecology developed from a discipline focussed on productivity and utilisation over conservation related topics to a stronger focus on social aspects today.