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Predator-Prey Simulation in JavaScript
Méry, Jozef ; Janoušek, Vladimír (referee) ; Peringer, Petr (advisor)
Študovanie populácie organizmov je veľmi užitočná oblasť výskumu. Dokáže pomôcť s predpovedaním, porozumením a možným zachovaním populácií. Táto bakalárska práca sa zameriava na modelovanie a simulovanie modelu dravec-korisť založeného na agentoch. Medzi najpodstatnejšie vlastnosti agentov patrí schopnosť zhlukovania založená na modeli boids vytvorený C. Reynoldsom, reprodukcia a mutácia. Výsledok tejto práce je konfigurovateľná prehliadačová aplikácia, ktorú možno použiť na simulovanie rôzných situácií a získanie štatistických údajov. Aplikácia obsahuje šablóny nastavení, ktoré boli simulované. Výsledky simulácií sú krátko zhodnotené.
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Development of soil nematode communities during primary and secondary succession
Benetková, Petra ; Frouz, Jan (advisor) ; Hendrychová, Markéta (referee) ; Renčo, Marek (referee)
Biodiversity loss is one of the biggest threats of our era. Habitats with all the unique species linked with them disappear due to the landscape changes and various mankind activities, namely obtaining of resources. Open-cast mining and intensive agriculture are an example of human activities that vastly degrades soil and diversity of its fauna. Therefore, ecosystem restoration is a way how to mitigate those losses and conserve or even bring back unique habitats. Despite the fact that most of restoration projects aim at plant communities, interest of soil fauna communities restoration increased amongst scientists lately. Nematodes serve as a very useful tool for a soil food web quality assessment. Their characteristics, such as various body length or different feeding habits makes them fit into almost all important ecological niches within the soil fauna group. This together with the fact that they are amongst first to colonize new habitats allows us to track changes in soil food web during primary or secondary succession. Moreover, using similar methodology and specific nematode indices developed over years enable comparison between different habitats and stages of succession. Restoration of soils and soil processes represent serious challenge in many restoration projects. Various restoration...
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Natural enemies of the European spruce bark beetle \kur{Ips typographus}
BÁRTA, Jiří
Bark beetles (Scolitynae) are among the most important pests of forest stands, where they cause extensive damage, especially in spruce monocultures. Their negative effect is to attack the host tree, which is its source of food and at the same time provides them with space for reproduction. The bark beetle is able to have several generations per year under suitable temperature conditions. One of the most widespread is consi-dered to be the European spruce bark beetle Ips typographus. This species is able to search for weakened and abiotically damaged trees. Integrated Pest Management of forests includes several effective methods against bark beetles. The most used met-hods include the installation of feromone traps, traps trees and poisoned tripods. The European spruce bark beetle is in their population regulated by many natural enemies. From parasitoids such as Coeloides bostrichorum and Rhopalicus tutela and predators Thanasimus formicarius and Medetera spp. to pathogenic microorganisms such as entomopathogenic viruses, bacteria, protozoa, microsporidia and especially entomo-pathogenic fungi belonging to the order Hypocreales. The most important species is the fungus Beauveria bassiana, which has the greatest potential in the biological pro-tection of spruce stands.
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Use of macroorganisms and microorganisms in biological control of aphids
BOŠKA, David
Aphids are one of the most important species of pests, occurring on all continents except Antarctica. Aphids are harmful mainly by sucking, honeydew production and transmitting hundreds of viral diseases. The most important greenhouse aphids occurring in the Czech Republic are the green peach aphid (Myzus persicae) and the cotton aphid (Aphis gossypii). Their danger lies in the rapid development cycle, when there is a rapid increase in populations. Despite the great damage they cause, aphids are very defenceless and small insect with a large number of naturally occurring enemies. The most important natural enemies are predators, parasitoids and entomopathogenic fungi. In the biological control of plants against aphids, the predator ladybeetles (Coccinellidae), lacewings (Chrysopidae) and the aphidophagous gall midge (Aphidoletes aphidimyza) are mainly used. In the nature, aphids are also regulated by hoverflies (Syrphidae). The most important aphid parasitoids are mainly the parasitic wasps Aphidius colemani, Aphidius ervi and Aphelinus abdominalis. From the microorganisms, the polyphagous entomopathogenic fungi are used, they cause primary infections in several species of pests. From the microorganisms, entomopathogenic fungi are mainly entomopathogenic fungi that can attack polyphagous more species of harmful organisms. The bioproducts based on entomopathogenic fungi Lecanicillium lecanii, Beauveria bassiana and Isaria fumosorosea are available on the foreign market. They were developed for biological control against aphids and other pests.
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PREDATION PRESSURE ON ARTIFICIAL CATERPILLARS INDICATES ENEMY-REDUCED TIME AND SPACE
SEIFERT, Carlo Lutz
This thesis explores patterns of predation on artificial caterpillars in two neotropical lowland rainforest ecosystems. The specific aim was to test if enemy-reduced time and space does exist for physical undefended caterpillars. Our results indicated that larval Lepidoptera are capable to lower predation risk by nocturnal foraging and by avoiding habitats of high light irradiance. Thus, habitat-specific host plant choice by adult females and a timely scheduled foraging behaviour of the caterpillars could remarkably increase the survival rate of immature stages.
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Jsou parmy obecné v době výtěru "jedovaté" pro ostatní vodní organismy?
ŠVEJDA, Pavel
This bachelor thesis deals with fish toxicity with the emphasis on the barbel (Barbus barbus Linnaeus, 1758). Its tissues and especially roe cause poisoning to human known as a "barbel cholera". Possible lethal effects of barbel the killer shrimp Dikerogammarus villosus (Sowinsky, 1894), the marbled crayfish Procambarus virginalis Lyko, 2017 and the round goby Neogobius melanostomus (Pallas, 1814) were examined in this thesis. Different types of tissues and early life stages of barbel were used due to the indistinct distribution of possible toxin in fish body. In addition, using a behavior test, where marbled crayfish were used as an experimental organism, we monitored possibilities of toxin detection by consumer. Our results suggest that there is no evidence of barbel lethal toxicity on chosen consumers. We also did not find evidence that crayfish are able to recognize flesh of ready and unready to reproduce barbel. To sum up, we did not find evidence that toxin which is present in barbel body affect given consumers. It can be given either their co-evolution (arms race) or their ancestors had never been susceptible on this toxin. Thus, there can only be a spontaneous effect of mentioned toxin on mammals or humans.
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Predator-Prey Simulation in JavaScript
Méry, Jozef ; Janoušek, Vladimír (referee) ; Peringer, Petr (advisor)
Študovanie populácie organizmov je veľmi užitočná oblasť výskumu. Dokáže pomôcť s predpovedaním, porozumením a možným zachovaním populácií. Táto bakalárska práca sa zameriava na modelovanie a simulovanie modelu dravec-korisť založeného na agentoch. Medzi najpodstatnejšie vlastnosti agentov patrí schopnosť zhlukovania založená na modeli boids vytvorený C. Reynoldsom, reprodukcia a mutácia. Výsledok tejto práce je konfigurovateľná prehliadačová aplikácia, ktorú možno použiť na simulovanie rôzných situácií a získanie štatistických údajov. Aplikácia obsahuje šablóny nastavení, ktoré boli simulované. Výsledky simulácií sú krátko zhodnotené.
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Semiaquatic bugs as predators and prey and their use in natural history teaching
JANDA, Václav
The aim of this thesis is to create an overview of scientific findings about the prey and the predators of the representatives of infraorder Gerromorpha, their feeding habits and defence strategies against predators. Gerromorphans are adapted for life on the surface of various water bodies ranging from puddles to open ocean. Majority of water striders feed on insect fallen upon water surface, hatching larvae of aquatic insect or micro-crustacean. Gerromorphans locate their prey by sight and by sensory detection of ripples at water surface caused by prey. Gathering in schools turned out to be an efficient defence strategy against predators. Some species have compound eyes with specialized ommatidia which enable them to see prey on the surface as well as predator under surface. A proposal of the use of Gerromorpha in natural history teaching is part of this thesis. Gerromorphans are convenient for teaching of natural history thanks to the possibility of observation of piercing and sucking mouthparts and various food relations such as predation, cannibalism or kleptobiotic relation. Undemanding rearing of gerromorphans enables easy realization of experiments and observations under school conditions.
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Challenges of Bengal tiger (Panthera tigris tigris) conservation in the tropics: lessons learned from the Chitwan National Park of Nepal
BHATTARAI, Bishnu Prasad
This research deals with the challenges of the conservation of tiger (Panthera tigris tigris) in the Chitwan National Park of Nepal and aims to be a model for tiger conservation in the tropical areas of other tiger range countries. Despite the high level of public concern and major investments during the last few decades for conservation, wild tigers continue to be under grave threat, and their preservation now requires, more than ever before, using reliable ecological knowledge for their conservation interventions. In this dissertation, I investigated various factors that affect on tiger conservation in this park: population status of prey, dietary patterns of tiger and its impact on sympatric carnivores (e.g., leopard) and increasing human-wildlife conflicts, effects of habitat structures and human disturbances on prey and predator species abundance and distribution.
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Natural enemies of bark beertle Ips typographus
Zelený, Jiří ; Lozan, Aurel
Totally 49 species of predators and 22 species of parasitoids are contributing to the population regulation of bark beetles, namely Ips typohraphus, in spruce forest of the Czech republic. The most encountered predators of bark beetles in our samples during 1998-2003 were: Thanasimus formicarius (Coleoptera), Medetera signaticornis and Lonchaea bruggueri (Diptera): hymenopteran parasitoids: Coeloides bostrichorum, Dendrosoter middendorfii, Cosmophorus klugii (Braconidae): Rhopalicus tutela, Roptrocerus xylophagorum, Tomicobia seitneri a Dinotiscus eupterus (Pteromalidae). The siricid wasp Ibalia leucospoides (Cynipoidea, Ibaliidae) is recorded too.
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