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1
Ober, Karen Ann. "The evolution of arboreal carabid beetles." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/289746.
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The diversity of many groups of organisms is related to the evolution of features that contribute to rapid radiations. This project reconstructed the phylogeny of carabid beetles in the subfamily Harpalinae, a speciose group of terrestrial predators. The phylogenetic inference focused on the sister group relationships, the monophyly of the subfamily and the tribal relationships within harpalines. Molecular sequence data, primarily from 28S ribosomal DNA and the wingless gene, were collected from more than 200 carabid beetles. Parsimony, minimum evolution distance, maximum likelihood, and Bayesian phylogenetic analysis methods were used to reconstruct the phylogeny of harpalines. Brachinine bombardier beetles and austral psydrines were found to be closely related to the harpaline clade. Within harpalines, zuphiites formed a clear clade as did pseudomorphines + graphipterines + orthogoniines. However the lebiomorph assemblage and the tribe Lebiini were not monophyletic. With the use of harpaline phylogenetic hypotheses, the evolution of the arboreal lifestyle was elucidated within the subfamily, including the rate and number of origins and losses of arboreality. Correlated evolution of several morphological characters and habitat was explored. Significant correlation of adhesive subtarsal setae and bilobed fourth tarsomeres on carabid legs were found with arboreality and may be arboreal adaptations, while long legs and long elytra are probably not associated with arboreality. The relationship of other morphological characters with arboreality is not clear. Harpalines may have been part of a rapid radiation of species diversity, where many lineages invaded new ecological niches and evolved novel morphological features to become adapted to their environment.
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Belaoussoff, Svenja. "Carabid beetles as indicators of tillage disturbance." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0023/NQ51029.pdf.
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Koivula, Matti. "Carabid beetles (Coleoptera, Carabidae) in boreal managed forests : meso-scale ecological patterns in relation to modern forestry." Helsinki : University of Helsinki, 2001. http://ethesis.helsinki.fi/julkaisut/mat/ekolo/vk/koivula/.
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Warner, Douglas James. "The potential of carabidae in the control of insect pests of winter oilseed rape." Thesis, University of Hertfordshire, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366035.
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Sutton, D. J. "Diversity and spatial distribution of carabid beetles in Bernwood forest." Thesis, Oxford Brookes University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379683.
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Tooley, Josephine Anne. "Weed seed predation by Carabid beetles in arable farming systems." Thesis, University of Reading, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408983.
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Lewis, David W. "Estimation of population densities of carabid beetles in cereal crops." Thesis, University of Leicester, 1988. http://hdl.handle.net/2381/34131.
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A model is presented which aims to predict population densities of carabid beetles from pitfall-trap data. This is not normally possible because of interspecific differences in activity patterns, resulting in differences in the rate at which individuals of different species encounter traps. Experiments carried out both in the laboratory and in the field on 10 species of Carabidae reveal that another factor, the rate of avoidance of traps following encounters, also differs interspecifically and should be taken into account before any predictions of abundance using pitfall-trap data are attempted. Data on the activity patterns of 5 of these species is used to simulate movement of individual beetles on a hypothetical grid of pitfall traps in the memory of a computer. Activity is simulated for a number of different durations and the proportion of individuals of each species encountering traps is determined for each duration. This parameter is regarded, for each species at each duration, as an estimate of the probability of an individual encountering a trap in the field. This parameter is combined with the avoidance rate to modify pitfall- trap data collected over an equivalent period. This gives a modified estimate (corrected for activity and avoidance) of the relative abundance of species in pitfall traps. This relative abundance is compared interspecifically with absolute abundance estimates from the field to determine the accuracy of the model. A discussion of the assumptions accompanying the model is followed by suggestions for further refinements so that it might be used in the future to predict the absolute abundance of carabids which are natural enemies of agricultural pests such as aphids.
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Mair, Jacqueline. "The role of Pterostichus madidus and Nebria brevicollis as predators of the slug Deroceras reticulatum." Thesis, University of Newcastle Upon Tyne, 2000. http://hdl.handle.net/10443/382.
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Slugs are important pests in many agricultural crops and potential biological control agents are being studied as an alternative to molluscicide application. The role of the carabids Pterostichus madidus (Fabricius) and Nebria brevicollis (Fabricius) as predators of the slug Deroceras reticulatum (MUller) was examined in the laboratory. These generalist beetle species were only capable of killing small, healthy slugs (<0.1 ig) as they were unable to overcome the defence mucus production of larger slugs. Dead slugs were scavenged in preference to killing healthy slugs. The relatively high proportion of positive serological results from field caught carabids may reflect a high scavenging rate rather than actual predation on live slugs. Slugs are difficult prey items for generalist beetles to overcome due to their defence mucus production. Results suggest that few slugs will be consumed in the presence of alternative prey which are less difficult for beetles to overcome. Slugs which could no longer produce defence mucus were readily attacked by both beetle species. Although beetles killed few healthy slugs the presence of beetles influenced slug behaviour with slugs of all sizes foraging for shorter periods of time. Any reduction in slug activity on the soil surface would in turn lead to a reduction in seedling damage. The results suggest that the role of potential predators in pest control can only be evaluated fully with a detailed understanding of their behaviour.
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Hawthorne, Amanda Jane. "Variation in the distribution of carabid beetles in cereal field headlands." Thesis, University of East Anglia, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262565.
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Okuzaki, Yutaka. "Coexistence of carabid beetles by trophic niche differences and premating isolation." 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/120695.
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Sasabe, Masataka. "The genetic architecture underlying species differences in genital morphology of carabid beetles." 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/120698.
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Chungu, Donald [Verfasser], and Roland [Akademischer Betreuer] Brandl. "Impact of land use on assemblages of carabid beetles (Coleoptera: Carabidae) in Zambia / Donald Chungu. Betreuer: Roland Brandl." Marburg : Philipps-Universität Marburg, 2014. http://d-nb.info/1064097707/34.
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Chen, Zhong-Zhao. "The effect of insecticides on dynamics of soil insect pests and carabid beetles (Coleoptera: Carabidae) in corn agroecosystems /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487944660929929.
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Bryan, K. M. "The responses of carabid and staphylinid beetles to patches of their cereal aphid prey." Thesis, University of Southampton, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.481551.
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Beaudry, Suzanne. "Effects of forest site preparation methods on carabid beetle (Coleoptera:Carabidae) diversity." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22718.
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The objective was to analyze the effects of logging and prescribed burning on carabid beetles (Coleoptera: Carabidae) at a jack pine stand and white spruce plantations in order to assess short-term impacts of these forestry practices on the diversity of this beetle group. In addition, soil scarification was also included at the jack pine stand. Based on previous reports on forest disturbance influences on carabids, it is hypothesized that short-term effects of studied forestry practices do not reduce carabids' diversity. Four carabid assemblage characteristics were compared: (a) number of catches; (b) dry mass; (c) species richness; and, (d) diversity index. Species responses and dry mass distributions were also investigated. Treatments either increased or maintained studied variables compared with control sites. Diversity indices were highest in burnt-over areas. Similar response patterns of species or groups of species were observed in both forest types. The presence of regenerating sites among the natural landscape increased carabid diversity.
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Baines, Danica Darlene Sonya. "Evaluation of adult carabid beetles (Coleoptera:Carabidae) as predators of the carrot weevil, Listronotus oregonensis (Coleoptera:Curculionidae)." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63753.
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Alexander, Keith N. A. "The population ecology of some woodland carabid beetles, with particular reference to their dispersive behaviour." Thesis, Royal Holloway, University of London, 1986. http://repository.royalholloway.ac.uk/items/ed4c46b0-bbb8-4f5e-8697-b9d09211b8d1/1/.
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The mobility of carabid beetles in the field has been studied by a number of researchers in recent years, but the small scale movements are still poorly understood. The populations of five species of carabid beetles living in a Surrey oakwood were therefore investigated using pitfall trapping and individual marking techniques over a period of three years. Five aspects of the complications associated with the interpretation of pitfall trapping and mark-release-recapture studies were investigated: (i) baiting of the traps by the catch itself, (ii) escape ability of captured beetles, (iii) changes in behaviour following overlong procedures between capture and release, (iv) density effects produced in trapping, and (v) effects of marking procedures on behaviour and survival. No effects could be demonstrated for (i), (iv) and (v). However, the escape rate in Nebria brevicollis was shown to be very high, and the behaviour of the same species affected by the length of time between capture and subsequent release. More than 3000 recaptures of marked beetles were made. Survival into a second breeding season was found to be commonplace in all five species; a few even entered a fourth. The distributions of the beetles within the study area were aggregated, particularly so in Nebria, where it was also shown that the beetles tend to remain in the areas where they are in the highest densities. Distributions changed little with season. Peak displacement rates were associated with the breeding seasonin Nebria but, whereas this fell off with the onset of winter in first season beetles, the level remained high in second season individuals. Pterostichus madidus exhibited a significant lack of displacement with time, except with males during the breeding season. Greatest activity and dispersal was found in August in first season males, but June and July with second season. Abax parallelepipedus beetles were found to be most active early in the season. Very few beetles of the species were found to disperse 100 metres or more within the study area. The concept of home range was examined in relation to ground beetles. Site attachment could not be demonstrated in any species, although other aspects of the trapping results indicated some form of home ranging behaviour.
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Marrec, Ronan. "Étude multi-échelle des déterminants des patrons de structuration et de dynamique spatiale de populations de coléoptères carabiques dans les agroécosystèmes." Thesis, Poitiers, 2014. http://www.theses.fr/2014POIT2302/document.
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Dans ce travail de thèse nous avons cherché à déterminer (i) les facteurs structurants des populations des carabiques dominants dans les paysages agricoles et (ii) leur(s) échelle(s) spatiale(s) et temporelle(s) d'influence, afin d'inférer des processus individuels et populationnels impliqués dans le maintien des espèces, en réponse à l'hétérogénéité spatiotemporelle des agroécosystèmes. Notre étude a été réalisée dans trois régions agricoles de l'ouest de la France, contrastées selon leur degré d'intensification agricole, en utilisant des échantillonnages basés sur des pots-pièges et des tentes à émergence et réalisés à plusieurs périodes de l'année.Une des principales originalités de ce travail est d'avoir caractérisé les agroécosystèmes à différentes échelles, tant (i) spatiales : le patch d'habitat, le paysage, la région ; que (ii) temporelles, en considérant à la fois l'environnement présent et celui de l'année précédente. De plus, nous avons essentiellement caractérisé l'influence de la dynamique des habitats sur les dynamiques de distribution et d'abondance et la dispersion des populations de carabiques.Notre étude a abouti à trois résultats majeurs. (1) La dynamique spatiale des espèces de carabiques étudiées est fortement influencée par les types d'habitats et leur instabilité temporelle à différentes échelles spatiales. Nous avons en effet mis en avant l'importance de l'hétérogénéité temporelle des paysages agricoles sur la dynamique spatiale des populations carabiques utilisant la matrice agricole. (2) La dispersion et les mouvements entre parcelles sont une condition importante du succès de ces espèces dans les paysages agricoles et semblent être principalement induits par les rotations de cultures. (3) Du fait de grandes tailles de populations et d'une dispersion efficace importante, la structuration spatiale et génétique des populations reste faible à l'échelle des paysages agricolesCarabid beetles (Coleoptera: Carabidae) play an important role in agriculture as natural enemies of pests. The development and application of practical techniques for managing their populations is a central challenge for sustainable agriculture and depends on detailed knowledge of the ecology of individual species. However, this information is relatively scant for even the most common species of interest in agricultural landscapes. Both agricultural practices and landscape structure have been shown to affect carabid distribution and abundance. In particular, crop rotation and associated mechanical practices affect arthropod abundance either directly, through mortality and emigration, or indirectly, by affecting local microhabitat conditions. Consequently, distribution shifts are expected to occur in response to the temporal instability of annual crops.The aim of this study was to determine (i) factors which structure populations of dominant carabid beetles over agricultural landscapes and (ii) their spatial and temporal scales of influence, in order to infer individual and population processes involved in species maintain, in response to agroecosystems' spatiotemporal heterogeneity. Surveys were conducted in three agricultural areas of western France contrasted in their degree of agricultural intensification, using both pitfall and emergence traps located within fields of the dominant crops and their immediate environment (field margins). At the field scale, we found that: (i) the studied carabid species used crop and non-crop habitats differently during the reproductive period and while overwintering and exhibited different strategies of habitat use; (ii) carabids were more active-abundant within oilseed rape fields than in other types of habitats; (iii) important distribution shifts were observed among habitat patches depending on habitat type and season.At the landscape scale, we found that: (i) landscape composition in both the current and previous years influenced carabid activity-density and distribution at different spatial scales; (ii) non-monotonous landscape effects on carabids were observed, which indicate the importance of considering contrasted landscapes to correctly explore the effect of landscape variables; (iii) Poecilus cupreus populations were structured spatially and genetically at very large spatial scales; (iv) male-biased dispersal was suggested in this species.Overall, results suggest that inter-field movements and active habitat selection rather than differences in survival rates determine distribution and abundance dynamics of dominant carabid species in agricultural landscapes. In addition, data suggest that redistributions mainly occur before overwintering likely in response to autumn cultural practices. High dispersal abilities are key traits for species maintain in highly instable environments, such as agricultural landscapes, and are highly selected in carabid species communities
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Clergué, Boris. "Évaluation de l'impact des pratiques agricoles sur les fonctions de la biodiversité à l'aide d'indicateurs agri-environnementaux : approche globale et développement d'un indicateur de "résistance aux stress biotiques"." Thesis, Vandoeuvre-les-Nancy, INPL, 2008. http://www.theses.fr/2008INPL048N/document.
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Des outils d’évaluation pertinents sont nécessaires pour évaluer l’impact des pratiques agricoles sur les fonctions assurées par la biodiversité de l’échelle de la parcelle à l’échelle du territoire. L’objectif et l’innovation du présent travail a été d’explorer une nouvelle méthode de création d’un outil d’évaluation des fonctions de la biodiversité. Nous avons choisi comme méthode d’évaluation les indicateurs agri-environnementaux, qui permettent d’évaluer l’impact des pratiques agricoles sur les compartiments de l’environnement (eau, sol, air, faune et flore) et aident à la prise de décisions. Nous proposons donc une architecture générale d’un indicateur de biodiversité fonctionnelle et le détail d’un indicateur de fonction agronomique d’importance: la résistance aux stress biotiques. Au sein de cet indicateur se trouve un sous-indicateur : le « rôle des auxiliaires terrestre ». Les carabes seront utilisés comme auxiliaire modèle pour la construction de ce sous-indicateur. Deux méthodes de construction d’indicateurs sont comparées: une méthode à dire d’expert et une méthode par fouille de données, cette deuxième méthode représentant une innovation de la thèse. Les résultats de ces méthodes sont ensuite comparés à des mesures de terrain conduit sur le territoire de Vittel. Les mesures de terrain ont concerné le suivi des populations de carabes, et l’organisation du territoire agricole. Un traitement par un système d’information géographique a permis la validation des indicateurs obtenusRelevant tools for assessment are necessary to evaluate the impact of agricultural pratices on the functions provided by biodiversity at the plot scale to the landscape scale. The goal and the innovation of this work has been to explore a new method of creation of an assessment tool of the biodiversity functions. We have chosen like assessment method the agri-environmental indicators, which make it possible to evaluate the impact of agricultural practices on environment compartments (water, soil, air, fauna and flora) and help to decision-making. We thus propose a general architecture of an indicator of functional biodiversity and the detail of an agronomic function indicator of importance: resistance to the biotic stresses. Within this indicator, an under-indicator is: the « role of the terrestrial auxiliaries ». Carabids will be used as model auxiliary for the construction of this under-indicator. Two building methods of indicators are compared: a method with expert saying and a method with data mining, this second method representing an innovation of the thesis. The results of these methods are then compared with field datas leads on the Vittel territory. Field datas related to the follow-up of the carabid populations and the organization of the agricultural landscape. A treatment by a geographical information system allowed the validation of the indicators obtained
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Wytrykush, Carla M. "Implications of spruce budworm (Lepidoptera: Tortricidae: Choristoneura fumiferana Clem.) management for the species diversity of moths, Lepidoptera, and carabid beetles (Coleoptera: Carabidae) in the Manitoba boreal forest." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ62874.pdf.
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Charalabidis, Alice. "Effect of inter-individual variabilities and intraguild interferences on the foraging stratégies of seed-eating carabid species." Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCK035/document.
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Faire un choix n’est pas juste un évènement spontané. La recherche d’une ressource alimentaire, par exemple, implique un investissement temporel et est donc en conflit avec d’autres activités essentielles telles que la vigilance pour les prédateurs. Ainsi être sélectif augmente le risque de se faire attaquer par un prédateur. Par ailleurs, être sélectif implique aussi de rejeter beaucoup de potentielles options avant de finalement en accepter une et donc accepter une perte non négligeable d’opportunités en présence de potentiels compétiteurs. Pour ces raisons, une réduction du niveau de sélectivité est attendue chez un individu exposé à une situation de forte compétition ou à un fort risque de prédation. Les carabes évoluent au sein de communautés composées, pour la plupart, d’un nombre important de potentiels compétiteurs et prédateurs. Les connaissances actuelles en écologie comportementale et en écologie prévoient que le comportement d’approvisionnement alimentaire des coléoptères carabiques devrait varier en fonction des niveaux de risques de compétition et de prédation qu’ils rencontrent et donc de la composition des communautés dans lesquelles ils se trouvent. Dans cette thèse, nous avons mesuré les changements de sélectivité alimentaire de deux espèces de carabes en présence de signaux de prédateurs ou de compétiteurs. A l’aide d’expériences de laboratoire effectuées à différentes échelles spatio-temporelle, nous avons réussi à montrer que la sélectivité alimentaire d’un carabe granivore Harpalus affinis peut varier en fonction du contexte dans lequel il cherche sa nourriture et être diminuée en présence de prédateurs. Par ailleurs le sexe des individus, l’espèce de graine qui leur est proposée et l’intensité du risque auquel ils sont confrontés semblent aussi avoir un effet sur la variation de sélectivité des individus. Aucun lien n’a cependant été trouvé entre le statut immunitaire ou la personnalité des individus et leur niveau de sélectivité alimentaire. Testé dans des conditions similaires, le carabe omnivore Poecilus cupreus, quant à lui, ne fait pas varier sa sélectivité pour les ressources testées. S’ils sont extrapolables ces résultats pourraient servir à expliquer la grande variabilité des taux de prédation de graines au champ par les carabes rapportés dans les différentes études. Ces résultats pourraient permettre aussi d’expliquer la difficulté d’extrapolation existante entre les taux de prédation de graines mesurés en laboratoire et les résultats obtenus au champ. Globalement, cette thèse confirme qu’une meilleure compréhension du processus de prise de décision chez les carabes est essentielle pour évaluer leur efficacité en tant que potentiels auxiliaires de culturesMaking a choice requires, implicitly, an investment of time in one behaviour at the expense of an investment in another. Being choosy would increase the risk of losing many food item opportunities to competitors, and is directly in conflict with other essential tasks such as predator avoidance. Individuals are thus expected to adjust their level of choosiness in response to the competition and predation context. The available behavioural ecological theory and the empirical ecology of carabids would suggest that competition and predation interference induces changes in the foraging behaviour of carabid individuals. Carabids typically operate within communities in which competition and predatory interference interactions occur and are ever present; there are high levels of intraguild interference. A better understanding of how risks of these two interference interactions modify individual decision making for prey would therefore help to improve the biocontrol of weeds by communities of carabids. This thesis focused on how changes in level of choosiness occur when individual carabids forage under intraguild interference. Using laboratory experiments, done at different spatio-temporal scales, we demonstrate that the decision-making processes of foraging carabids might differ between contexts, between species and between individuals. Our focal species, the granivore Harpalus affinis, was found to reduce its level of choosiness while foraging under intraguild interference. In doing so H. affinis individuals increased their overall rate of seed acceptance. This change in choosiness was dependant on the intensity of the risk, the seed species offered in test and the sex of individuals. We found no link between individual levels of choosiness and either immunity or personality traits. When tested under similar conditions, individuals of the omnivorous carabid Poecilus cupreus did not change their level of choosiness for seeds. These findings would help explain the high variability in seed predation rates observed between studies conducted in-field, and the differences observed between laboratory studies and fields measurements in carabids. Globally, this thesis has confirmed that a deeper understanding of the decision making process of carabids seed-eating species is requires to evaluate their choice of prey and assess their relevance as biological control agents in the wild
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Puech, Camille. "Hétérogénéité des pratiques agricoles biologiques et conventionnelles dans les paysages bretons : effets sur les communautés d'insectes auxiliaires à différentes échelles." Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1S117/document.
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En réponse aux pertes de biodiversité et à une insécurité alimentaire croissante, l’agriculture moderne doit se tourner vers une gestion plus durable des paysages agricoles. L’Agriculture Biologique (AB) est considérée comme une solution prometteuse à ces enjeux. En effet, ses pratiques agricoles étant globalement plus favorables aux ennemis naturels de ravageurs que celles de l’Agriculture Conventionnelle (AC), elle pourrait permettre de remplacer l'utilisation des pesticides par celle du contrôle biologique. Cependant, les études évaluant ces effets restent contradictoires, probablement car elles ne tiennent pas compte de la diversité des pratiques réalisées en AB et en AC. A plus large échelle, les pratiques ont par ailleurs rarement été considérées dans la description de l’hétérogénéité paysagère, bien que la nature et l’organisation spatiale de la matrice agricole soit susceptible d’affecter les espèces qui y vivent. L’objectif de ce travail de thèse est d’évaluer les effets de la diversité et de l’organisation spatiale des pratiques en AB et en AC sur les insectes auxiliaires, à l’échelle de la parcelle et du paysage. Un travail de terrain a été réalisé en 2012 et 2013 en Ille et Vilaine. Quarante paires de parcelles de blé d’hiver en AB et en AC ont été sélectionnées, réparties le long d’un gradient paysager de surfaces en AB. Dans chaque parcelle, les communautés d'ennemis naturels de pucerons (coccinelles, carabes, parasitoïdes) ont été échantillonnées. Des enquêtes ont permis de caractériser les pratiques agricoles réalisées par les agriculteurs dans les parcelles suivies et dans leur environnement paysager. Nous avons mis en évidence l’existence d’une large diversité de pratiques agricoles dans les systèmes en AB et en AC. A l’échelle parcellaire, les effets des pratiques sur la diversité des insectes auxiliaires sont forts, les systèmes en AB leur étant globalement plus favorables. Considérer un niveau plus fin de description des pratiques nous a permis d’identifier celles qui affectent réellement les insectes et de montrer qu’il est possible de favoriser leur présence, quel que soit le mode de production. A l’échelle du paysage, nous n’avons mis en évidence aucun effet de l’étendue et de l’organisation de l’AB sur les ennemis naturels. Une description plus fine des pratiques nous a malgré tout permis de souligner l’importance de certaines stratégies de pratiques, à certaines échelles. A partir de ces résultats, nous proposons des pistes pour l’aménagement des paysages agricoles. Les problèmes méthodologiques liés à la description des pratiques agricoles à l’échelle du paysage sont également discutésDue to the loss of biodiversity and increasing food insecurity, modern agriculture must evolve toward a more sustainable management of agricultural landscapes. Organic Farming (OF) is considered as a promising solution to meet this challenge. Organic practices are indeed generally more favorable to pest natural enemies than Conventional Farming (CF), suggesting that pesticides could be replaced by biological control. However, studies evaluating these effects are contradictory, probably because they do not consider the diversity of practices implemented in OF and CF. On a broader scale, practices have rarely been considered in the description of landscape heterogeneity, although the nature and configuration of farmland must affect species. The target of this PhD work is to evaluate the effects of the diversity and spatial organization of organic and conventional farming practices on insect natural enemies, at field and landscape scales. A fieldwork was conducted in 2012 and 2013 in Brittany. Forty pairs of organic and conventional winter wheat fields were selected, distributed along a landscape gradient of OF area. In each field, aphid natural enemies (ladybirds, carabid beetles, parasitoids) were sampled. We interviewed farmers to characterize farming practices implemented in fields and their surrounding landscape. We observed a wide diversity of farming practices in OF and CF. At field scale, effects of practices on the diversity of natural enemies were strong, OF being overall more favorable. Considering a finer description of practices allowed us identifying those really affecting insects, and showing they can be enhanced regardless of the farming type. At landscape scale, we found no effect of the OF area and configuration on natural enemies. With a more detailed description of practices, we however highlighted the importance of some farming strategies, at some scales. Based on these results, we open up avenues to manage agricultural landscapes. Methodological issues related to the description of farming practices on large areas are also discussed
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Mulerčikas, Povilas. "Epigėjinių žygių rūšinė sudėtis ir pasiskirstymas Pašilės girininkijos lapuočių medynuose." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2009. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20090114_155043-61361.
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Darbo tikslas: nustatyti žygių rūšinę sudėtį ir pasiskirstymą Pašilės girininkijos lapuočių medynuose.
Darbo objektas: Žygiai ( Coleoptera, Carabidae ) Pašilės girininkijos lapuočių medynuose.
Darbo metodai: Stebėjimai buvo vykdomi 2007 metais Pašilės girininkijos lapuočių medynuose. Buvo išskirti penki miško tipai (jie skyrėsi augavietės sąlygomis), kuriuose buvo įtaisyta 50 Barberio žeminės gaudyklių. Kiekviename miško tipe nustatoma dominuojanti rūšis, rūšių individų skaičius, dominantų sezoninis aktyvumas, rūšinės įvairovės rodiklis, ekologinė ir zoogeografinė žygių charakteristika.
Darbo uždaviniai: vykdyti žygių rinkimą Pašilės girininkijos lapuočių medynuose 2007m.,
apdoroti gautus duomenis, išanalizuoti žygių rūšinės sudėties ypatumus atskiruose miško tipuose.
Darbo rezultatai: Tyrimo metu penkiuose miško tipuose buvo sugauta 11801 žygių, atpažintos 53 žygių rūšys, priklausančios 26 gentims. Tiriant žygių rūšis buvo nustatyta, kad viena jų (Calosoma inquisitor) įrašyta į Lietuvos Raudonąją knygą. Tiriant žygių gausumo sezoninę dinamiką išskirti du pakilimai: gegužės - birželio mėn. ir rugpjūčio mėn.. Žygių rūšinės įvairovės rodiklis atskiruose miško tipuose svyravo nuo 1,411 kiškiakopūstiniame ąžuolyne, iki 2,549 žibuokliniame – kiškiakopūstiniame uosyne. Atliekant tyrimo analizę išryškėjo tendencija, kad rūšinė įvairovė daugiausiai priklauso nuo dirvožemio drėgnumo ir derlingumo. Kuo derlingesnis ir drėgnesnis dirvožemis tuo didesnė žygių rūšinė įvairovė.
Remiantis... [toliau žr. visą tekstą]Object: to define specific composition and distribution of carabid beetles at different forest types at Aukštasis tyras Mire Reserve. Subject: Pašilės Methods: Observations were performed in 2007. At 5 forest types 50 Barber's ground traps were equipped. Dominating species, number of species individuals, seasonal activity of dominating species, index of species variety, ecological and zoographical characteristics of carabid beetles were ascertained at each forest type. Tasks: 1. To set the link between forest type and existing species composition of carabid beetles. 2. To study the subordination between richness of carabid beetles and forest type. Results: During the study at 5 forest types 11801 carabid beetles were caught, 53 species of carabid beetles which belong to 26 genera were recognized. During the study of carabid beetle species it was established that one of them (Calosoma inquisitor) was included into the Red Book of Lithuania. Studying the seasonal dynamics of carabid beetle richness two peaks were set: in may ¬June and August. Carabid beetle species variety at different forest types fluctuated from 1,411 at Oksalido – Quercetum to 2,549 at Hepatico-oksalido Fraxinetum. Making an evaluation of the study a tendency emphasised that species variety mostly depends on soil humidity and productivity. The more productive and humid the soil is, the bigger species variety of carrabid beetles is. Evaluating all collected carabid beetle species according to zoogeographical... [to full text]
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Boursault, Aline. "Caractérisation des relations trophiques entre composantes d'un agroécosystème : le cas de la prédation des graines d'adventices par les Carabidae." Thesis, Dijon, 2012. http://www.theses.fr/2012DIJOS119/document.
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L’agroécologie offre de nouvelles perspectives à l’agriculture et ainsi une voie vers une gestion alternative des adventices à travers différents mécanismes écosystémiques de régulation. La prédation des graines est l’un d’entre eux et son étude fait depuis peu l’objet de recherches visant à approfondir les connaissances relatives à ce processus. Ce travail de thèse cherche (i) à caractériser la prédation des graines d’adventices, les principaux prédateurs Carabidæ et la ressource en graines disponible à l’échelle locale dans une culture courante (blé d’hiver); (ii) à étudier précisément les profils de prédation des principaux prédateurs et les interactions entre les composantes biologiques impliquées; (iii) à introduire des éléments de réponse relatifs au potentiel de régulation des communautés d’adventices via la prédation des graines par les Carabidæ. Des approches complémentaires ont été utilisées afin de répondre à ces problématiques : un suivi à long terme de terrain, des tests de préférences en laboratoire, une simulation des taux de prédation à long terme à partir des données ponctuelles ainsi qu’une étude à grande échelle des prédateurs et du stock de graines.L’étude des variations spatio-temporelles de la prédation via un dispositif de terrain durant la période d’activité des prédateurs a mis en évidence trois pics de prédation dont un seul correspond au pic de prédateurs (avant la moisson). La ressource en graines disponible au sol est quant à elle présente majoritairement lors du premier et du dernier pic de prédation, et aucune augmentation de ressource n’a été observée après moisson. Ces dynamiques semblent stables, restant valables indépendamment de l’échelle spatiale (intra ou interchamp) et des espèces carabiques et adventices étudiées.Toutes les espèces adventices ne font pas l’objet de la même intensité de prédation, et de manière générale, les graines de petites tailles ont été préférentiellement prédatées, au champ comme en test de cafétéria au laboratoire. Cependant, les espèces carabiques semblent avoir des profils de prédation différents entre guildes trophiques, ainsi qu’au sein d’une même guilde. De ce fait, la prise en compte des préférences de consommation dans l’étude des relations prédation-prédateurs tout comme la combinaison des données prédateurs et graines disponibles permet parfois d’améliorer les corrélations, notamment pour les espèces les plus prédatées.Une simulation de la prédation annuelle suggère des pertes en graines dues à la prédation non négligeables, pouvant atteindre pour l’espèce la plus prédatée, ici Viola arvensis, jusqu’à près de 80% des graines disponibles. En parallèle, une étude à grande échelle de l’évolution du stock de graines montre une corrélation négative entre prédateurs et évolution de la banque de graines, suggérant une régulation de la banque de graines via les prédateurs carabiques.L’ensemble de ces résultats suggère que prendre en compte la diversité fonctionnelle des communautés de prédateurs et d’adventices est un point important dans la compréhension de la prédation compte tenu des préférences de consommation des prédateurs et des dynamiques temporelles des différents acteursAgroecology gives evidence of new perspectives in agriculture, and open doors for alternative weed management approaches through different regulation mechanisms. Seed predation is one of them, and the interest is growing to deepen knowledge, relative to this process. This Phd work aims (i) to describe weed seed predation, the dominant carabid predators and the available resource at a local scale in a common crop (winter wheat); (ii) to study predation profiles of main predators, and the pair-wise correlations between the biological components of the system; (iii) to bring new insights regarding potential regulation of weed communities, through seed predation by carabid beetles. Complementary approaches have been used to tackle these aspects: a long-term field study, some cafeteria tests, a simulation of annual predation rates from point-to-point estimates, as well as a large-scale field study of predators and seed resource. Study of spatio-temporal variations of predation, via field experiment during the main activity period of carabids, has shown a three-peak pattern, one of them corresponding to predators’ peak, just before harvest. Weed resource available on soil surface is high in the first and last peaks of predation, and no increase of resource has been observed after harvest. These dynamics are independent of the spatial scale (intra or inter-field) and carabid species. The different weed species do not show the same levels of predation, and, as a whole, small-seeded species are more eaten, in both lab and field conditions. However, carabids have different preferences among trophic guilds, but also within a same guild. Therefore, in order to study predation, it is essential to combine predators and seed data, as well as considering preferences of predators. A simulation of annual seed predation shows important rates of seed loss, reaching up to 80% for the most predated species, V.arvensis. A large scale study of seed bank shows a negative correlation between predators’ activity density and seed bank change, assuming that there is a seed bank regulation by carabid predators. All together, these results show that functional diversity of predators’ and weeds’ communities is a key factor in understanding predation
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Asteraki, Elizabeth J. "Factors affecting the reproduction and development of two contrasting species of carabid beetle (Coleoptera, Carabidae)." Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297497.
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Newell, Simon C. "Dispersal in carabids." Thesis, University of Plymouth, 1986. http://hdl.handle.net/10026.1/2725.
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The study consisted primarily of a number of surveys in brassica fields, using pitfall and gutter traps. At all sites a number of different species of carabids were marked and released. From the pitfall trapping it was found that different carabid species inhabitated different parts of the field, particularly in relation to the field boundaries. Two common species, Nebria brevicollis and Bembidion lampros, over-wintered in the hedgebanks, moving out into the fields in the spring. Two other common species, Pterostichus melanarius and Harpalus rufipes, were primarily associated with the field, but activity in the field boundaries continued later into the year. Marking concentrated on four species; P. cupreus, P. melanarius, H. rufipes and N. brevicollis. At all sites the recapture rate of rufipes was much lower than that of P. melanarius, though they are of similar size. Using this data, mean displacement/day was calculated for each species. To identify the causes for the differences in recapture rate between the species, two species were individually tracked at night, in the field. Positions every two minutes were recorded and the distance and turn between each point measured. The results showed that H. rufipes had a higher turn rate and moved less than melanarius. The data from tracking was incorporated into a computer simulation model which recreated the beetles' tracks, using the same time interval. Traps were added and the model used to simulate the recapture experiments in the field. Changes in dispersal patterns were used to create differences in the catch in different patches. It was found that changes in turning behaviour could not produce changes in density, because of behaviour at the boundaries. Delaying the change in behaviour produces differences in numbers, but orientation is the most likely mechanism. The relationship between step length, turn and catch was also evaluated.
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Carrington, Terry R. "Factors influencing habitat selection and activity of ground beetles (Coleoptera: Carabidae) in central Appalachia Part I : The influence of soil and soil surface characteristics on habitat selection by Carabidae ; Part II : Precipitation and temperature fluctuations : effects on Carabidae activity ; Part III : The effects of two microbial insecticides for gypsy moth control on Carabidae populations /." Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2368.
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Thesis (M.S.)--West Virginia University, 2002.Title from document title page. Document formatted into pages; contains viii, 114 p. : ill., maps. Vita. Includes abstract. Includes bibliographical references.
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Gosney, Louise Mary. "Phylogeography and population structure of carabid beetle Pterostichus melanarius." Thesis, University of East Anglia, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247110.
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Tripathi, Hemant Gangaprasad. "Biodiversity of the African savanna woodlands : how does it change with land use?" Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/28965.
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The savanna woodlands of Southern Africa, colloquially termed the miombo, are poorly described in terms of biodiversity compared to other biomes. They have therefore been underrepresented in the wider understanding of how land use intensification is shaping global biodiversity. Land use change is known to reduce biodiversity and disrupt intactness of ecological communities with consequences for ecosystem functioning, resilience, and services. Miombo woodlands are described as biodiversity hotspots due to a high endemism of species and the presence of megafauna. At the same time, they are also considered dynamic socio-ecological systems shaped by disturbances and the land use activities of people. The patterns of biodiversity change in these tropical ecosystems may, therefore, have their own unique contexts, understanding of which will be essential for biodiversity and land use management in these ecosystems. In this thesis, I identified the patterns of biodiversity change in response to the two major land use practices in the two dominant woodland types in southern African woodlands: the selective logging due to charcoal production in the mopane woodlands, and agricultural expansion in the miombo. I also examined the impact of two main disturbance agents, humans and elephants, on habitat structure and biodiversity in mopane woodlands. Across all chapters in this thesis, I investigated the effects of land use change and habitat modification on biodiversity empirically using chronosequences. To understand biodiversity change, I employed a hierarchical multilevel modelling approach making inferences at the three levels of ecological communities: species, community, and meta-community (set of ecological communities at different sites). I selected six villages in the charcoal production hotspot of southern Mozambique and carried out field surveys for three taxonomic groups: trees, mammals and ground beetles. I modelled the counts of trees and beetles and incidence of mammals using meta-community occurrence models in a Bayesian framework with the intensity class of the villages, above-ground biomass and land cover type as predictors. The results suggested that the species richness of trees and mammals declined by 12 and 8.5 % respectively while that of beetles increased by 3.5%, albeit non-significantly. In addition, the beta diversity of trees decreased while that of mammals increased. The results show that while both trees and mammals reduced in richness, they responded differently to charcoal production in terms of community organisation. The trees underwent subtractive homogenisation (decrease in alpha and beta diversities) primarily because of deterministic processes induced by selective harvesting of tree stems for charcoal. Mammal communities, on the other hand, showed subtractive heterogenization (decrease in alpha, but increase in beta diversity) mainly due to random extinctions. In the agriculture frontier of miombo-dominated northern Mozambique, I investigated the effects of fragmentation and habitat loss caused by agricultural expansion on diversity and composition of trees and mammals. I modelled the occurrences of trees and mammals using occupancy models with the fragmentation and quantity of woodland cover as predictors. The model showed that most tree species (n=10), mainly the timber and firewood species, linearly declined in population size as fragmentation increased. Mammals, on the other hand, showed a nonlinear response. Seven mammal species increased at the lower levels of fragmentation. However, at the higher levels, none of the mammal species increased while two declined. Similarly, the species richness of trees linearly declined, while that of mammals increased up to a fragmentation level of 55-65% and declined above this limit. The beta diversity of trees increased with fragmentation while that of mammals decreased. The results suggest that, although fragmentation reduces species richness of both trees and mammals, it affects their species compositions in different ways. Trees undergo subtractive heterogenization due to random species losses while mammals experience subtractive homogenisation mainly due to the combined effects of fragmentation-led habitat loss and intensified hunting. Finally, this study concludes that, above 75% fragmentation or below 26% habitat quantity, both taxonomic groups endure biodiversity loss. The threshold results here corroborate similar habitat quantity thresholds (20-30%) observed elsewhere in different ecosystems. However, they differ with the widespread notion that above 30% habitat quantity, the effect of fragmentation is non-existent. The results here emphasize that taxonomic groups respond differently, the diversity and population size of mammals reduced only after the habitat threshold, whereas, those of trees showed linear decrease with fragmentation most likely due to fragmentation-led habitat loss. Lastly, I examined the effects of disturbance by humans and elephants on habitat structure and bird diversity by conducting a space for time substitution comparison in the mopane woodlands of Zambia. To examine the woodland structure, I modelled the structural attributes of habitat (stem diameter, stand density, and basal area) using mixed models with the proportion of affected stems by humans and elephants as explanatory variables. I found that elephant disturbance was associated with higher stem diameters, low stand densities, but no change in basal area. Human disturbance, on the other hand, was related to reductions in stand density and basal area, but no change in the stem diameter. Further, I tested species and functional diversity of birds against the covariates of habitat structure and disturbance. I found that bird communities reduced in species richness in both, human as well as elephant disturbed areas. However, the functional diversity did not change with elephant disturbance. I concluded that human disturbance reduces woody biomass (basal area is correlated with woody biomass) of mopane woodlands and functional diversity of birds whilst elephants do not. In this thesis, I conclude that human driven land use change in the miombo woodlands erodes alpha diversity of all taxonomic groups. However, increases in beta diversity of mammals with charcoal land use and trees in agricultural land use may maintain their diversities at the meta-community level.
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Downie, Iain Stuart. "Aspects of habitat selection and the influence of boundaries on some upland invertebrate communities." Thesis, Durham University, 1995. http://etheses.dur.ac.uk/5281/.
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Aspects of the distribution and ecology of some surface-dwelling invertebrates were examined on different high-altitude vegetation types in the north Pennines, England. The influence of the boundary between habitats on the invertebrate community was also investigated, and the effects of habitat heterogeneity on invertebrate distribution were discussed. Spiders and carabids were sampled from the dominant vegetation types on the plateaux of three mountain summits (Cross Fell, Littie Dun Fell and Great Dun Fell) in 1991 using pitfall traps. Multivariate methods were used to classify and ordinate the sites based on their fauna and to assess the influence of the local environmental variation on the species distribution. Three spider assemblages were recognised based on their common species composition; two short Festuca grassland assemblages and a Nardus/Eriophorum assemblage associated with greater vegetation density. The results suggest that variation in the vegetation structure is the major factor influencing spider distribution on the summit plateaux, with slope and soil depth also contributing. The carabids appeared too widely distributed to assign to any specific vegetation types. The influence of the interface between different vegetation types on the spider and carabid fauna was sampled using pitfall traps in 1992-3. At the boundary between two highly contrasting habitats (sheep pastures and conifer plantations) an edge effect was found in both groups, where species richness was elevated. The major contribution to this increase was the mixing of both pasture and plantation species, species specific to the interface were few. The edge effect at this interface was narrower but larger in spiders than in carabids. At the boundary between two more similar habitats (grazed and ungrazed upland grassland) the edge effect was much reduced, species richness was not elevated, and the level of overlap between habitats was much wider. Edge permeability, structural similarity and altitude were considered the most important factors for the differences between boundaries studied. It is inferred that in the high altitude invertebrate community most species are widespread crossing boundaries between vegetation types regularly, though some species may have affinities to particular habitats for different aspects of their ecology. The implications that this study has for understanding the effects and impacts of habitat heterogeneity at the landscape level are discussed, such as invertebrate movement patterns, population dynamics and management aspects.
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Hamilton, J. Graeme. "The foraging behaviour of the carabid beetle Pterostichus madidus (F.)." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/38027.
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Hawes, Catherine. "Factors influencing communities of ground beetles (Coleoptera: Carabidae) in plantation forests." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302256.
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Armsworth, Clare Gillian. "Influence of a carabid beetle predator on the behaviour and dispersal of slug pests." Thesis, Cardiff University, 2005. http://orca.cf.ac.uk/55967/.
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It is becoming increasingly recognised that natural enemies in arable land, particularly polyphagous predators such as carabid beetles, may help to suppress populations of pests, and that appropriate management of such predators may lead to a satisfactory level of pest control. Previous work has shown that a polyphagous carabid predator, Pterostichus melanarius, is capable of affecting the spatial and temporal dynamics of slug pest populations. This project is an examination of how P. melanarius affects the survival, behaviour and dispersion of two important slug pests, Deroceras reticulatum and Arion intermedins, and how this information applies to spatial and temporal data previously obtained from the field. Deroceras reticulatum, but not Arion intermedius, elicited a variety of anti-predator behaviour in the presence of substrates previously exposed to the predator. The movements of slugs in arenas, incorporating a zone containing paper upon which the predatory beetles had previously been maintained and a control zone, were recorded at intervals. Significantly more slugs of all the size classes tested accumulated on the control half of arenas after 24 hours, with small slugs being quickest to respond. Slugs avoided paper exposed to both male and female beetles. Slugs also avoided paper exposed to another predatory carabid, Pterostichus madidus, but not to Harpalus affinis, a phytophagous carabid. Slugs did not respond to paper that had been exposed to beetles and then stored for five days prior to the test. Changes in parameters of movement of slugs when in the presence of P. melanarius chemicals were detected using a video-tracking system. These changes are consistent with a kinesis that would enable slugs to rapidly escape from areas where beetles were recently present. Despite this no changes in the rate of dispersion of D. reticulatum juveniles was detected in mini-plots previously exposed to P. melanarius. However, adult D. reticulatum reduced feeding and egg-laying and increased refuge on soil previously exposed to P. melanarius. Chemicals on the exterior of P. melanarius were isolated and two compounds were found to reduce feeding by D. reticulatum on leaf discs compared to control discs. One of these chemicals is currently being analysed using mass spectroscopy and NMR to determine it's structure and identity. It was concluded that D. reticulatum have evolved behavioural responses to chemical cues from either this generalist carabid predator in particular, or carabid beetles generally, many species of which include molluscs in their diets. During a video-tracking study of beetle movements, some evidence was found for the detection and response of beetles to slug mucus, and amputation work suggested that the palps may be important in slug detection. Previous feeding experience was found not to influence prey choice in P. melanarius during a food choice experiment, with beetles always selecting a mixed diet when offered. Analysis of spatial data showed that slug size, but not beetle sex, was important in the spatial relationship between the predator and the prey, and this agrees with results from the laboratory experiments of slug behaviour. This work has added to the evidence provided by other studies that some generalist predators can have significant effects on the dynamics of pest populations and therefore may become useful biocontrol agents for pests if effectively managed. The implications of this work in the field of predator-prey ecology and for the efficacy of P. melanarius as a biological control agent of slugs are discussed.
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Brown, Nicola Jane. "Carabid ecology in organic and conventional farming systems : population density, diversity and high resolution spatial dynamics." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340435.
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Bertrand, Colette. "L'hétérogénéité spatiale et temporelle des paysages agricoles influence les auxiliaires généralistes des cultures et le potentiel de contrôle biologique des ravageurs." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S161/document.
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Les carabes et les araignées sont des auxiliaires généralistes susceptibles d'exercer un contrôle efficace des ravageurs des cultures. La structure et composition de leurs communautés, ainsi que l'efficacité du contrôle biologique, dépendent de l'hétérogénéité des paysages, et en particulier de la présence d'habitats semi-naturels. Mais le rôle de la mosaïque agricole, susceptible de présenter une forte hétérogénéité dans l'espace et dans le temps, reste aujourd'hui peu connu. L'objectif de ce travail a été d'évaluer les effets de l'hétérogénéité spatiale et temporelle des paysages agricoles sur des auxiliaires généralistes et sur le potentiel de contrôle biologique. Nous avons échantillonné les communautés de carabes et d'araignées dans des parcelles de céréales, et estimé le potentiel de prédation par des pucerons sentinelles collés sur des cartes de prédation. Nous avons caractérisé l'hétérogénéité spatiale des paysages autour des parcelles de céréales par le pourcentage d'éléments boisés et la longueur du réseau de haies, la taille moyenne des parcelles agricoles, et la diversité des cultures. Nous avons également mis au point quatre nouvelles métriques qui synthétisent différents aspects de l'hétérogénéité temporelle interannuelle des surfaces cultivées. Nos résultats montrent qu'au printemps les araignées sont plus abondantes dans les parcelles de céréales situées dans des paysages composés de petites parcelles. Au début de l'été, ces paysages favorisent également les taux de prédation de pucerons mesurés par les cartes de prédation, et l'abondance des carabes qui se reproduisent au printemps et qui hivernent en tant qu'adultes dans des habitats semi-naturels. Les carabes qui hivernent dans le sol des parcelles au stade larvaire et se reproduisent à l'automne sont quant à eux favorisés par la diversité des cultures dans le paysage. Nos résultats montrent enfin que l'hétérogénéité temporelle de la mosaïque agricole - caractérisée par les changements de la diversité de cultures au cours des cinq dernières années - favorise elle aussi certaines espèces de carabes communément rencontrées dans les parcelles agricoles (Poecilus cupreus ou Pterostichus melanarius) et susceptibles de jouer un rôle important en tant qu'auxiliaires. Ces résultats mettent en avant le rôle complémentaire des bordures de champs non cultivées et de la mosaïque des cultures pour différents groupes d'auxiliaires, et soulignent l'importance de prendre en compte l'hétérogénéité spatiale et temporelle des surfaces cultivées dans l'étude de la biodiversité des paysages agricoles. Dans le contexte de réduction des produits phytosanitaires, nos résultats suggèrent que des paysages présentant une diversité de cultures importante variable dans le temps, et des petites parcelles qui favorisent l'intrication entre les habitats semi-naturels et les cultures, sont susceptibles de favoriser les auxiliaires généralistes ainsi que le potentiel de contrôle biologique des ravageursIn the context of reducing pesticide use, the potential role of some arthropod groups as pest natural enemies provides them an ecological and economic interest. In particular, ground beetles and spiders are generalist predators likely to be effective biocontrol agents. Previous studies have shown that the structure and composition of their communities, as well as the effectiveness of biological control, are influenced by landscape heterogeneity, and in particular by the presence of semi-natural habitats. However, the role of the crop mosaic, which can be highly heterogeneous in space and time, have been little considered. The main objective of our study was to determine the influences of spatial and temporal heterogeneity of agricultural landscapes on generalist natural enemies and the potential for biological pest control. We sampled carabid and spider communities in winter cereal fields, and estimated biological control potential using sentinel aphids glued on predation cards. We characterized the spatial heterogeneity of the landscapes around each cereal field by 1) the amount of wooded habitats and the length of the hedgerow network, 2) the average size of the agricultural fields, and 3) crop diversity. We also proposed four new metrics that synthesize different aspects of the multi-year temporal heterogeneity of cropped areas. Our results show that in spring, landscapes characterized by small fields, and therefore by a high density of non-cropped field margins, promote spiders abundance in cereal fields. In early summer, landscapes with small fields also promote aphid predation rates and the abundance of carabid spring breeders, which overwinter as adults in semi-natural habitats. Crop diversity promotes the abundance of carabids overwintering in soils of arable fields and breeding in autumn. Our results also show that the temporal heterogeneity of the crop mosaic - characterized among other things by the changes in crop diversity over a five year period - benefits some carabid species commonly found in agricultural landscapes (such as Poecilus cupreus and Pterostichus melanarius) which are likely to play an important role as pest natural enemies. These results highlight the complementary role of the crop mosaic and the non-cropped field borders for generalist natural enemies, and show the importance of taking into account the spatial and temporal heterogeneity of the cultivated area in further ecological studies on biodiversity in agricultural landscapes. In the context of reducing pesticide use, our results suggest that landscapes with 1) a high crop diversity that change over time, and 2) small fields that promote the interspersion between crops and semi-natural habitats, are likely to promote generalist natural enemies and biological pest control
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Lin, Ying-Chi. "Spatio-temporal dynamics of ground beetles (Coleoptera: Carabidae) in a mosaic forested landscape." Thesis, University of East Anglia, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427087.
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Small, Emma Clare. "The biodiversity and population of carbid beetles (coleoptera, carabidae) in fragmented urban habitats." Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289261.
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Moore, Wendy. "Molecular Phylogenetics, Systematics, and Natural History of the Flanged Bombardier Beetles (Coleoptera: Adephaga: Carabidae: Paussinae)." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/194110.
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This dissertation focuses on the systematics of the Paussinae, a lineage of approximately 775 beetle species all of which produce explosive defensive chemicals and many which are obligate associates of ants (myrmecophiles). This dissertation includes six discrete studies, which taken together span the spectrum of systematic research. It includes taxonomic projects on both larval and adult paussines. It also includes phylogenetic investigations, based on DNA sequence data and morphological data, that address the evolutionary relationships among the major lineages within Paussinae as well as the evolutionary position of the Paussinae within the beetle suborder Adephaga. The inferred trees are used to study character evolution of physiological and behavioral traits of these organisms in a phylogenetic framework. This work sets the stage for a lifetime of work on this fascinating group.
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Duflot, Rémi. "Hétérogénéité fonctionnelle et biodiversité : quel est le rôle des interfaces ou lisières dans les paysages agricoles ?" Phd thesis, Université Rennes 1, 2013. http://tel.archives-ouvertes.fr/tel-01019974.
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L'hétérogénéité du paysage, définie par la composition en habitats et leur configuration spatiale, est considérée comme un facteur majeur affectant la biodiversité. Cependant, les effets de la composition et de la configuration sont souvent confondus du fait de corrélations entre les descripteurs de ces deux composantes. Il est crucial de déterminer leurs effets indépendants pour comprendre les processus qui contrôlent la biodiversité, et allouer les ressources dédiées à la conservation des espèces aux actions de gestion les plus pertinentes. L'objectif de cette thèse est, grâce à la mise en place de protocoles pseudo-expérimentaux dans l'ouest de la France, d'étudier les effets indépendant de la composition et de la configuration paysagère sur la richesse spécifique, la composition spécifique et la composition en traits fonctionnels des coléoptères carabiques et plantes vasculaires. Ces indices de diversité ont été mesurés au niveau du paysage (diversité gamma), et différentes représentations paysagères ont été testées pour comprendre le rôle de l'hétérogénéité de l'espace cultivé, au-delà de la seule prise en compte des habitats semi-naturels. Les résultats indiquent que l'hétérogénéité paysagère joue un rôle de filtre écologique sur les espèces de carabes et de plantes en fonction de leurs traits fonctionnels. La composition paysagère affecte la composition spécifique de ces groupes, les divers habitats hébergeant des communautés différentes. La configuration affecte la diversité des carabes en lien avec des processus possibles de complémentation entre habitats, tandis qu'elle n'a pas d'effet sur la diversité des plantes, qui ne semble donc pas déterminée par les processus de dispersion. Enfin, nos résultats soulignent que l'hétérogénéité liée aux habitats agricoles contribue à la diversité gamma.
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Blake, Shona. "Effects of management practices on the ground beetle assemblages of grassland and related habitats (Coleoptera: Carabidae)." Thesis, Connect to e-thesis, 1996. http://theses.gla.ac.uk/702/.
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Thesis (Ph.D.) - University of Glasgow, 1996.Ph.D. thesis submitted to the Environmental Sciences Department, Scottish Agricultural College, 1996. Includes bibliographical references. Print version also available.
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Ouisse, Tiphaine. "Phenotypic and genetic characterisation of the carabid beetle Merizodus soledadinus along its invasion gradient at the subantartic Kerguelen Islands." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1B017/document.
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Le commerce mondial et les mouvements humains accroissent les probabilités de transport à longue distance de propagules, et leur introduction dans de nouvelles aires géographiques. Dans certains cas, des espèces récemment établies peuvent devenir dominantes dans la communauté envahie. Malgré les menaces sur les communautés natives et le fonctionnement des écosystèmes, les invasions biologiques constituent des expériences naturelles qui permettent d’étudier les processus éco-évolutifs en temps réel, notamment l’impact de nouvelles interactions biotiques sur la composition et la dynamique des communautés, l’adaptation rapide à de nouvelles conditions environnementales, ou la dispersion en limite de répartition. Les îles océaniques sont particulièrement sensibles aux invasions biologiques en raison de la faible diversité de leurs communautés natives. Dans les terres australes françaises, le carabique marcheur Merizodus soledadinus, natif de Patagonie, a été accidentellement introduit à Kerguelen en 1913. La présente étude vise à comprendre les principaux mécanismes à l’origine du succès invasif de cet insecte aux Iles Kerguelen. Un large ensemble de méthodes ont été utilisée pour explorer les traits écologiques de M. soledadinus, des populations à la molécule. Les analyses génétiques confortent l’hypothèse historique d’un unique évènement d’introduction dans un seul site des Iles Kerguelen. Les populations échantillonnées le long du gradient d’invasion ne montrent pas de structuration génétique. Les traits phénotypiques mesurés montrent une forte différentiation entre les individus selon le temps de résidence des populations, confirmant l’hypothèse de tri spatial des populations au cours de l’expansion géographique. Nous avons démontré que l’expansion géographique et la sélection d’habitats par M. soledadinus est principalement gouvernée par la disponibilité en eau, comme le suggère par la forte sensibilité des adultes au stress hydrique. En parallèle, la colonisation d’habitats en altitude dépend des conditions thermiques, qui semblent être contraignantes pour cet insecte à partir de 200m d’altitude. La colonisation d’habitats d’altitude progresse pourtant, probablement assistée par le changement climatique. Pour finir, les adultes M. soledadinus sont longévifs et actifs toute l’année. Les connaissances apportées sur l’écologie de M. soledadinus et sur la dynamique de son expansion géographique suggèrent la poursuite de la colonisation de l’archipel par ce prédateur. L’ensemble de ces connaissances pourraient être utiles à la paramétrisation d’un modèle d’expansion géographique, qui permettrait de définir les routes de dispersion et les taux d’expansion, dans l’objectif d’assister les mesures de gestion par les agents de la Réserve naturelle des Terres Australes et Antarctiques FrançaisesGlobal trade and human movements increase the likelihood of long-distance transportation of propagules and their subsequent introduction into new geographic regions. In some instances, newly established species can become dominant in invaded communities, at the expense of native species. Besides threatening invaded communities and ecosystem functions, biological invasions constitute natural experiments that allow to study eco-evolutionary processes in real time, including the occurrence of new biotic interactions affecting community composition, rapid adaptation to novel environmental conditions, or dispersal evolution at range margins. Because of their impoverished native communities, oceanic islands’ ecosystems are particularly sensitive to biological invasions, and the French subantarctic islands are no exception. For instance, the flightless predatory carabid beetle Merizodus soledadinus is native from the southern tip of South America, and has been accidentally introduced to the Kerguelen Islands in 1913. In the present work, we aimed at understanding the main mechanisms underlying the invasive success of this insect at the Kerguelen Islands. Using a vast array of methodologies, ecological features of M. soledadinus were investigated with analytical procedures scaling from population to molecule through the individual level. Genetic investigations support the historically-based hypothesis of a single introduction event at a unique location of the Kerguelen Islands. No genetic structure was observed among individuals sampled from different populations along the invasion gradient. We tested the hypothesis of spatial sorting of populations during range expansion, by exploring phenotypic changes among individuals sampled along the invasion gradient. The measured phenotypic traits revealed major differentiation of adults according to the residence time of their populations, confirming the occurrence of spatial sorting of populations during geographic expansion. We also demonstrated that the geographic expansion of M. soledadinus, and microhabitat selection, are primarily governed by the availability of water resources, as suggested by the high sensitivity to water stress of adults of this ground beetle. In parallel, colonisation of altitudinal habitats is governed by thermal conditions, which seem to be physiologically constraining from 200m asl onwards. As the altitudinal distribution of M. soledadinus still extends, we concluded that ongoing climatic changes play a pivotal role in this expansion. Finally, adults of this ground beetle are long-lived and active year-round. The ecological knowledge of M. soledadinus characteristics and spatial expansion dynamics suggest that the colonisation process of the Kerguelen archipelago by this species will continue. Altogether, these data could be used for parametrising range expansion models that would delineate dispersal pathways and expansion rates, in the objective to assist stakeholders’ management decisions
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Humble, Shauna Marie. "Weeds and ground beetles (Coleoptera: Carabidae) as influenced by crop rotation type and crop input management." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ62758.pdf.
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Paling, N. J. "Studies on activity and population density of Pterostichus madidus (F.) (Coleoptera: Carabidae) using video recordings." Thesis, Cranfield University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305247.
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Timm, Anika Verfasser], and Thorsten [Akademischer Betreuer] [Aßmann. "Diversity of Ground Beetles and Saproxylic Beetles (Coleoptera: Carabidae + div. Saproxylic) in East Mediterranean Ecosystems (Israel) : Dispersal, Habitat, Activity and Reproduction / Anika Timm. Betreuer: Thorsten Assmann." Lüneburg : Universitätsbibliothek der Leuphana Universität Lüneburg, 2010. http://d-nb.info/1034147358/34.
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Priesnitz, Kai Uwe [Verfasser]. "Potential impact of Diabrotica resistant Bt-maize expressing Cry3Bb1 on ground beetles (Coleoptera: Carabidae) / Kai Uwe Priesnitz." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2011. http://d-nb.info/1016243863/34.
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Kennedy, Peter John. "The effects of molluscicides on the abundance and distribution of ground beetles (Coleoptera, Carabidae) and other invertebrates." Thesis, University of Bristol, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.481794.
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Myrick-Bragg, Kennesha. "Effects of Olfactory Cues on the Movement Behavior of the Predatory Beetle Calosoma wilcoxi." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4437.
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Arthropod predators often use prey and conspecific cues to make foraging decisions. Calosoma wilcoxi (Leconte) is a voracious predatory beetle that specializes on lepidopteran larvae often found in the forest canopy, including the fall cankerworm. This study tested the hypothesis that C. wilcoxi uses olfactory cues to detect prey and conspecifics. A Y-tube olfactometer was used to test attractiveness to larvae, larval frass, conspecific cues, and volatiles from herbivore-damaged white oak leaves. C. wilcoxi did not preferentially choose the treatment in any of the experiments. There was no difference in mean time spent in the treatment or control arm for any of the cues assayed. The time to choose the treatment was significantly shorter in the female conspecific experiment only. I found no evidence that C. wilcoxi uses olfaction to locate prey; however, C. wilcoxi is attracted to conspecifics. C. wilcoxi may use conspecific cues to make informed foraging decisions.
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Deroulers, Paul. "Étude des interactions trophiques entre les communautés de carabes et de graines adventices sous l'angle d'un système proie-prédateur." Thesis, La Rochelle, 2017. http://www.theses.fr/2017LAROS030/document.
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La flore adventice est à la base des chaînes trophiques dans les agroécosystèmes. Leur diminution dans les parcelles cultivées est une des causes de la baisse de la biodiversité. Par conséquent, des alternatives sont étudiées pour diminuer l’utilisation des herbicides dans le cadre du plan ECOPHYTO. Par exemple, la gestion de la flore adventice via les consommateurs de graines. En effet, les agroécosystèmes sont des milieux où des espèces granivores ont les capacités de consommer les graines d’adventices. Parmi les vertébrés, nous pouvons y trouver des oiseaux (alouette des champs) ainsi que des micromammifères (mulot). Parmi les invertébrés, les carabes sont identifiés comme principaux granivores dans les agroécosystèmes tempérés. L’objectif général de cette thèse est d’étudier les interactions entre carabes et graines d’adventices afin d’apporter des connaissances sur les interactions interspécifiques et d’identifier les traits physiologiques des espèces influençant la force des interactions entre les espèces. Un protocole a été établi afin de standardiser toutes les expériences et de garder comme variables uniquement l’espèce de graines et celle du carabe. Ensuite, nous avons étudié les interactions entre les graines d’adventices et les carabes selon deux axes de recherche. Le premier a permis de comparer les niveaux de consommation de la communauté de carabes sur une même espèce de graines. Nous avons pu ainsi observer que la masse corporelle des carabes n’était pas en relation avec la variation des niveaux de consommation. Mais le ratio entre la longueur des mandibules et la largeur du labrum (force mandibulaire) a un effet significatif lorsque seules les espèces consommant plus de cinq graines sont prises en compte. Pour le deuxième axe, nous avons mesuré la consommation des carabes sur 42 espèces de graines pour identifier les capacités de consommation et explorer la stratégie d’alimentation selon deux caractéristiques : la masse des graines (taille) et leur concentration lipidique. Les graines de faibles masses avec un taux lipidique élevé sont mangées en plus grand nombre. Enfin, nous avons déterminé les types de réponse fonctionnelle pour évaluer le potentiel de régulation de 4 espèces de carabes sur deux espèces de graines d’adventices. Pour chaque espèce (mâle et femelle) nous avons trouvé une réponse fonctionnelle de type II, sauf pour les femelles de P.rufipes. Cependant nos résultats doivent être interprétés avec précaution car en milieu naturel d’autres facteurs interviennent dans les interactions, telle que la présence de proies alternatives ou d’autres prédateurs. En conclusion, nous montrons que les interactions entre les graines d’adventices et les carabes sont nombreuses et complexes. Les caractéristiques physiologiques intervenant dans les interactions sont très nombreuses et très variables selon les espèces. Des études supplémentaires sont nécessaires pour évaluer l’intérêt agronomique des carabes dans la gestion des adventicesWeed flora limits crop yields therefore herbicides inputs are important in order to manage weeds. Weeds are at the bottom of the trophic pyramid in agroecosystems, and this explains partly the decrease of biodiversity. Alternatives to manage weeds are studied to reduce negative effect of herbicides on the environment in order to preserve biodiversity. For example, weeds could be managed with granivorous species. Indeed, weed seeds are the origin of the weed community, thus seed consumption could limit weed abundance in cultivated fields. In agroecosystems, several taxa are known to be granivorous such as vertebrates (birds and rodents) and invertebrates (ground beetles). Ground beetles are considered as the main granivorous taxa in agroecosystems and are abundant in temperate agroecosystems. The main goal of this PhD was to study trophic interactions between communities, weed seed and ground beetles, with a prey-predator system in order to estimate the role of ground beetles through their seed consumption in weed seeds management. First, we established a protocol with standardize steps in order to restrain variables to weed seed species at ground beetles’ species. A similar protocol has been adapted to replicate experimentation with the same individuals to measure consumption at different weed seed densities. We then studied interactions between weed seeds and ground beetles with two research axes. We first explored interspecific variation of consumption on the same weed seeds species, Viola arvensis, by ground beetles. Body mass and ratios between mandible length and labrum width had no relation with seed consumption by ground beetles. Thus, other factors were suggested to explain consumption variation such as gut symbionts of ground beetles or preferences for specific weed seed species. Secondly, we measured consumption of 42 weed seed species by four ground beetles to identify abilities in weed seed consumption for these beetles and to explore feeding strategy according to two seed characteristics, seed mass (size) and seed lipid content. Generalism degrees are different according to ground beetles’ species and seem affected by physiological characteristics in both communities. Finally, to assess the potential in weed seed management of ground beetles we determined functional response to four ground beetles on two weed seeds species. We determined type II response for all species (male and female) tested, except for females of P.rufipes. Our results should be interpreted cautiously as, under natural conditions, generalist predators meet many alternatives prey and it could influence functional response type. We showed that there are many complex interactions between weed seed and ground beetles communities, especially due to a wide range of diversity in physiological characteristics in both communities. The potential of ground beetles to regulate seeds must be more precisely explored to evaluate their agronomic interest in weed management
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Lai, Changquan. "Potential applications of the natural design of internal explosion chambers in the bombardier beetle (Carabidae, Brachinus)." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62606.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2010.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student submitted PDF version of thesis.
Includes bibliographical references (p. 118-122).
The Bombardier Beetle (Carabidae, Brachinus) has a unique form of defense mechanism which involves the explosive mixing of hydroquinones and hydrogen peroxide in its internal explosion chambers and using the resultant high pressure to spray out a heated corrosive fluid containing p-benzoquinones in a controlled direction [1][2]. Three salient features of the internal explosion chambers were found to be instrumental in withstanding the high pressures generated from the explosive mixing and protecting the Bombardier Beetle's internal organs [3]. Using simulations performed with finite element analysis, it was discovered that such design features employed by the Bombardier Beetle are suitable for incorporation into helmet designs. An in-depth analysis of the market potential of such a design with respect to the motorcycle helmet market is presented along with implementation strategies and proposed business plans.
by Changquan Lai.
M.Eng.
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Bertoncelj, Irena. "Spatial dynamics of ground beetle (Coleoptera: Carabidae) assemblage in a forest and open habitat mosaic landscape." Thesis, University of East Anglia, 2009. https://ueaeprints.uea.ac.uk/10591/.
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This thesis explores the relative importance of within-patch habitat quality, the temporal persistence and spatial connectivity of habitat patches, for heathland ground beetle assemblages in a forested and open habitat landscape mosaic of Breckland, Eastern England. Comparison of the carabid fauna of two distinct landscape elements: remnants of once extensive lowland heathland and the pine plantations of Thetford Forest managed by rotational clear-felling, showed the high value of the forest landscape for carabid species restricted to grassland, heathland and sandy habitats (GHS). Within the forest landscape, temporal changes in carabid community in planted stands are determined by management and succession, with conditions suitable for GHS species persisting for just seven years after replanting. For persistence of GHS species within Thetford Forest permanent open space, representing approximately ten percent of the area, is essential. Habitat quality, particularly greater cover of bare sand, lower sward and shallow soil litter, were more important predictors of patch suitability for GHS species than patch size. Suitability of linear trackway elements within the plantation was determined by the surrounding matrix, with high GHS species richness in trackways surrounded by younger plantations (<20 years) and very few GHS in those surrounded by older plantations. Behaviour of the model arenicolous species Harpalus rufipalpis differed between these two types of trackways, with greater levels of activity and more leakage in poor quality trackways surrounded by older trees; thus only a subset of trackway elements will serve as corridors for conduit. Despite the interrupted nature of this network, colonisation of newly created clear-fells by GHS species was not affected by their isolation, at least at the current scale of management. Almost all GHS species recorded in permanent open habitats were shown to successfully colonise ephemeral open patches: colonists did not represent a subset of GHS species and were not filtered by dispersal ability.