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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Mechanics of forward flight in insects

Dudley, Theodore Robert January 1987 (has links)
No description available.
2

Taksonomska analiza vrsta iz podfamilije Syrphinae (Diptera: Syrphidae) u Srbiji / Taxonomic analyses of the species from subfamily Syrphinae (Diptera: Syrphidae) in Serbia

Nedeljković Zorica 16 December 2011 (has links)
<p>Redeterminacijom publikovanog i determinacijom novog materijala iz podfamilije Syrphinae na području Srbije su zabeležene 134 vrste iz 25 rodova. Sedam vrsta (<em>Chrysotoxum orthostylus </em>Vujić, in prep., <em>Chrysotoxum </em>aff.<em> festivum</em>, <em>Chrysotoxum </em>aff. <em>vernale, Dasysyrphus laskai</em> Doczkal &amp; St&aring;hls, in prep., <em>Melanostoma</em> aff.<em> mellinum, Paragus rarus</em> Vujić et al., in prep. i <em>Xanthogramma citrofasciatum </em>B Doczkal, in prep.) su nove za nauku i njihovi opisi se nalaze u pripremi. 14 vrsta su nove za faunu Balkanskog poluostrva, dok su 39 nove za faunu Srbije (uključujući i one koje su nove za Balkan).</p><p>Unutar vrste<em> Chrysotoxum festivum </em>uočena su dva fenotipa &bdquo;svetli&ldquo; i &bdquo;tamni&ldquo; koji se jasno razlikuju na osnovu niza morfolo&scaron;kih karaktera (&scaron;irina lica, &scaron;irina crne trake na licu, popra&scaron;enost čela, boja dlaka na mezonotumu i skutelumu, &scaron;irina oznaka na T2 i T3) kao i na osnovu veličine i oblika krila. Usled jasne divergencije pomenutih fenotipova kao i njihove simpatrije u pitanju su odvojene vrste.</p><p>Jasno izdvajanje fenotipova na osnovu morfolo&scaron;kih karaktera odraslih jedinki uključujući i parametre krila (veličinu i oblik) ustanovljeno je i unutar vrsta <em>Chrysotoxum vernale</em> i <em>Melanostoma mellinum.</em> Unutar vrste <em>Chrysotoxum vernale</em> se izdvajaju dva nezavisna taksona- <em>Chrysotoxum vernale</em> i <em>Chrysotoxum </em>aff. <em>vernale</em>, a unutar vrste <em>Melanostoma mellinum</em>- <em>Melanostoma mellinum </em>i<em> Melanostoma </em>aff. <em>mellinum</em>.</p><p>Zoogeografskom analizom je ustanovljeno da su najbrojnije vrste &scaron;irokog areala, koje čine čak 75,19% od ukupnog broja vrsta, 12 vrsta (9,02%) ima srednjeevropski, 10 severnoevropski (7,52%), a svega dve vrste (1,5%) južnoevropski tip areala. Dve vrste (1,5%) su ograničenog areala.</p><p>Dve vrste iz podfamilije <em>Syrphinae</em> spadaju u kategoriju strogo za&scaron;tićenih vrsta, dok pet spada u kategoriju za&scaron;tićenih vrsta na području Srbije (Uredbom Ministarstva za za&scaron;titu životne sredine i prostornog planiranja Republike Srbije od 2010. godine o za&scaron;titi strogo ugroženih i ugroženih divljih vrsta biljaka, životinja i gljiva). Razmatrajući status vrsta na evropskom nivou po Speight (2010) većina vrsta (118) pripada kategoriji neugroženih vrsta &bdquo;unthreatened&ldquo;, a po četiri kategoriji ugroženih vrsta &bdquo;threatened&ldquo; i vrsta čija se brojnost smanjuje &bdquo;decreasing&ldquo;.</p><p>Najvećim indeksom diverziteta (3,66) se odlikuje Duba&scaron;nica sa Malinikom, zatim slede Vr&scaron;ačke planine (H=3,62) i Kopaonik (H=3,59). Najniži indeks diverziteta imaju Bosilegrad (1,21) i dolina Tami&scaron;a (1,55) &scaron;to je i očekivano obzirom na broj sakupljenih primeraka i registrovanih vrsta.</p><p>Rad predstavlja sintezu faunističkih istraživanja vrsta iz podfamilije Syrphinae u Srbiji, taksonomsku analizu zabeleženih vrsta kao i razre&scaron;avanje taksonomskih problema unutar mnogih vrsta unutar kojih su oni bili prisutni.</p> / <p>This PhD thesis is about the taxonomic and faunistic revision of the Syrphinae hoverflies (Syrphidae) of Serbia. As a result of this study, 134 species of 25 genera were reported to Serbia. This account comprised seven species new to science: <em>Chrysotoxum orthostylus</em> Vujić, in prep.<em>Chryotoxum </em>aff. <em>festivum</em>, <em>Chrysotoxum</em> aff. <em>vernale</em>,&nbsp;<em> Dasysyrphus laskai</em> Doczkal &amp; St&aring;hls, in prep., <em>Melanostoma</em> aff. <em>mellinum</em>, <em>Paragus rarus</em>&nbsp;Vujić et al., in prep. and <em>Xanthogramma citrofasciatum</em> B Doczkal, in prep.. Additionally,&nbsp;&nbsp; 39 species were new to Serbia, 14 of them also new to the Balkan Peninsula.</p><p>A first approach to solve some taxonomic problems within three different hoverfly taxa is provided in this study. The examined material of <em>Chrysotoxum festivum</em> from Serbia exhibited two different phenotypes, &ldquo;light&rdquo; and &ldquo;dark&rdquo;. These phenotypes were defined by both landmark-based geometric morphometric characters of wings and other adult morphological characters (width of face, width of black stripe on face, frons pruinosity,colour of hairs on mesonotum and scutellum, width of stripes on terga 2 and 3, etc). The presented results together with the sympatry of the studied phenotypes suggested the&nbsp;&nbsp; existence of at least two different taxa within the species, currently known under the name <em>Chrysotoxum festivum</em>. Similarly, traditional characters in adult morphology and morphometric characters of wings (size and shape) showed the existence of two welldefined phenotypes both within the species <em>Chrysotoxum vernale</em> <em>(Chrysotoxum vernale</em> and <em>Chrysotoxum </em>aff. <em>vernale</em>) and the species <em>Melanostoma mellinum </em>(<em>Melanostoma mellinum </em>and <em>Melanostoma</em> aff. <em>mellinum</em>).</p><p>The zoogeographic analysis showed that most of the studied species are widespread in Europe (75,19%), and the rest of species are Central European (9,02%), Northern European (7,52%) or South European (1,5%).</p><p>At European level, 118 species are thought to be unthreatened, four threatened and four with decreasing populations according to the last version of Syrph the Net, the Database of European Syrphidae. In Serbia, two of the studied species are regarded as &ldquo;strictly protected&ldquo; and five as &ldquo;protected&ldquo; under the Regulation on the Promulgation and&nbsp;&nbsp; Protection of the Protected and Strictly Protected Wild Species of Plants, Animals and Fungi (Ministry of Environment and Spatial Planning, Serbia).</p><p>The localities of Duba&scaron;nica and Malinik have the highest values for the scored diversity index (H = 3.66), followed by Vr&scaron;ačke planine (H=3.62) and Kopaonik&nbsp; (H=3.59). Bosilegrad and Tami&scaron; have the lowest diversity values, 1.21 and 1.55 respectively, as it was expected by the low species richness and abundance of hoverflies recorded in these localities.</p>
3

Taksonomska analiza vrsta iz podfamilije Syrphinae (Diptera: Syrphidae) u Srbiji / Taxonomic analyses of the species from subfamily Syrphinae (Diptera: Syrphidae) from Serbia

Nedeljković Zorica 16 December 2011 (has links)
<p>Redeterminacijom publikovanog i determinacijom novog materijala iz podfamilije Syrphinae na području Srbije su zabeleţene 134 vrste iz 25 rodova. Sedam vrsta (Chrysotoxum orthostylus Vujić, in prep., Chrysotoxum aff. festivum, Chrysotoxum aff. vernale, Dasysyrphus laskai Doczkal &amp; St&aring;hls, in prep., Melanostoma aff. mellinum, Paragus rarus Vujić et al., in prep. i Xanthogramma citrofasciatum B Doczkal, in prep.) su nove za nauku i njihovi opisi se nalaze u pripremi. 14 vrsta su nove za faunu Balkanskog poluostrva, dok su 39 nove za faunu Srbije (uključujući i one koje su nove za Balkan). Unutar vrste Chrysotoxum festivum uočena su dva fenotipa &bdquo;svetli&ldquo; i &bdquo;tamni&ldquo; koji se jasno razlikuju na osnovu niza morfolo&scaron;kih karaktera (&scaron;irina lica, &scaron;irina crne trake na licu, popra&scaron;enost čela, boja dlaka na mezonotumu i skutelumu, &scaron;irina oznaka na T2 i T3) kao i na osnovu veličine i oblika krila. Usled jasne divergencije pomenutih fenotipova kao i njihove simpatrije u pitanju su odvojene vrste. Jasno izdvajanje fenotipova na osnovu morfolo&scaron;kih karaktera odraslih jedinki uključujući i parametre krila (veličinu i oblik) ustanovljeno je i unutar vrsta Chrysotoxum vernale i Melanostoma mellinum. Unutar vrste Chrysotoxum vernale se izdvajaju dva nezavisna taksona- Chrysotoxum vernale i Chrysotoxum aff. vernale, a unutar vrste Melanostoma mellinum- Melanostoma mellinum i Melanostoma aff. mellinum. Zoogeografskom analizom je ustanovljeno da su najbrojnije vrste &scaron;irokog areala, koje čine čak 75,19% od ukupnog broja vrsta, 12 vrsta (9,02%) ima srednjeevropski, 10 severnoevropski (7,52%), a svega dve vrste (1,5%) juţnoevropski tip areala. Dve vrste (1,5%) su ograničenog areala. Dve vrste iz podfamilije Syrphinae spadaju u kategoriju strogo za&scaron;tićenih vrsta, dok pet spada u kategoriju za&scaron;tićenih vrsta na području Srbije (Uredbom Ministarstva za za&scaron;titu ţivotne sredine i prostornog planiranja Republike Srbije od 2010. godine o za&scaron;titi strogo ugroţenih i ugroţenih divljih vrsta biljaka, ţivotinja i gljiva). Razmatrajući status vrsta na evropskom nivou po Speight (2010) većina vrsta (118) pripada kategoriji neugroţenih vrsta &bdquo;unthreatened&ldquo;, a po četiri kategoriji ugroţenih vrsta &bdquo;threatened&ldquo; i vrsta čija se brojnost smanjuje &bdquo;decreasing&ldquo;. Najvećim indeksom diverziteta (3,66) se odlikuje Duba&scaron;nica sa Malinikom, zatim slede Vr&scaron;ačke planine (H=3,62) i Kopaonik (H=3,59). Najniţi indeks diverziteta imaju Bosilegrad (1,21) i dolina Tami&scaron;a (1,55) &scaron;to je i očekivano obzirom na broj sakupljenih primeraka i registrovanih vrsta. Rad predstavlja sintezu faunističkih istraţivanja vrsta iz podfamilije Syrphinae u Srbiji, taksonomsku analizu zabeleţenih vrsta kao i razre&scaron;avanje taksonomskih problema unutar mnogih vrsta unutar kojih su oni bili prisutni.</p> / <p> This PhD thesis is about the taxonomic and faunistic revision of the Syrphinae hoverflies (Syrphidae) of Serbia. As a result of this study, 134 species of 25 genera were reported to Serbia. This account comprised seven species new to science: Chrysotoxum orthostylus Vujić, in prep., Chrysotoxum aff. festivum, Chrysotoxum aff. vernale, Dasysyrphus laskai Doczkal &amp; St&aring;hls, in prep., Melanostoma aff. mellinum, Paragus rarus Vujić et al., in prep. and Xanthogramma citrofasciatum B Doczkal, in prep.. Additionally, 39 species were new to Serbia, 14 of them also new to the Balkan Peninsula. A first approach to solve some taxonomic problems within three different hoverfly taxa is provided in this study. The examined material of Chrysotoxum festivum from Serbia exhibited two different phenotypes, &ldquo;light&rdquo; and &ldquo;dark&rdquo;. These phenotypes were defined by both landmark-based geometric morphometric characters of wings and other adult morphological characters (width of face, width of black stripe on face, frons pruinosity, colour of hairs on mesonotum and scutellum, width of stripes on terga 2 and 3, etc). The presented results together with the sympatry of the studied phenotypes suggested the existence of at least two different taxa within the species, currently known under the name Chrysotoxum festivum. Similarly, traditional characters in adult morphology and morphometric characters of wings (size and shape) showed the existence of two well-defined phenotypes both within the species Chrysotoxum vernale (Chrysotoxum vernale and Chrysotoxum aff. vernale) and the species Melanostoma mellinum (Melanostoma mellinum and Melanostoma aff. mellinum). The zoogeographic analysis showed that most of the studied species are widespread in Europe (75,19%), and the rest of species are Central European (9,02%), Northern European (7,52%) or South European (1,5%). At European level, 118 species are thought to be unthreatened, four threatened and four with decreasing populations according to the last version of Syrph the Net, the Database of European Syrphidae. In Serbia, two of the studied species are regarded as &ldquo;strictly protected&ldquo; and five as &ldquo;protected&ldquo; under the Regulation on the Promulgation and Protection of the Protected and Strictly Protected Wild Species of Plants, Animals and Fungi (Ministry of Environment and Spatial Planning, Serbia). The localities of Duba&scaron;nica and Malinik have the highest values for the scored diversity index (H = 3.66), followed by Vr&scaron;ačke planine (H=3.62) and Kopaonik (H=3.59). Bosilegrad and Tami&scaron; have the lowest diversity values, 1.21 and 1.55 respectively, as it was expected by the low species richness and abundance of hoverflies recorded in these localities.</p>
4

Farming system and landscape complexity affects pollinators and predatory insect communities differently

Håkansson, Michaela January 2014 (has links)
It has been argued that organic farming sustains a higher biodiversity than conventional farming. This might promote the ecosystem services that exist in agricultural landscapes such as pollination and pest control. Here, I examined the effect of farming system (organic vs. conventional) with respect to the time since farming system transition, landscape heterogeneity and plant richness on pollinating and predatory insects. In total, data from 30 farms were used, of which 20 were organic and 10 were conventional. The data were analyzed using general linear models and model averaging. The results show that insect groups responded differently to various factors. Pollinators were more sensitive to landscape complexity, showing an increase of abundance and species richness with an increased heterogeneity. Predators on the other hand reacted to farming system, where there was an increase in abundance and species richness on organic farms.
5

Motion Vision Processing in Fly Lobula Plate Tangential Cells

Lee, Yu-Jen January 2014 (has links)
Flies are highly visually guided animals. In this thesis, I have used hoverflies as a model for studying motion vision. Flies process motion vision in three visual ganglia: the lamina, the medulla, and the lobula complex. In the posterior part of lobula complex, there are around 60 lobula plate tangential cells (LPTCs). Most of LPTCs have large receptive fields where the local direction sensitivity suggests that they function as matched filters to specific types of optic flow. LPTCs connect to descending or neck motor neurons that control wing and head movements, respectively. Therefore, in this thesis I have focused on the electrophysiological responses of LPTCs to gain understanding of visual behaviors in flies. The elementary motion detector (EMD) is a model that can explain the formation of local motion sensitivity. However, responses to higher order motion, where the direction of luminance change is uncorrelated with the direction of movement, cannot be predicted by classic EMDs. Nevertheless, behavior shows that flies can see and track bars with higher order motion cues. I showed (Paper I) that several LPTCs also respond to higher order motion. Many insects, including flies, release octopamine during flight. Therefore, adding octopamine receptor agonists can mimic physical activity. Our study (Paper II) investigated the effect of octopamine on three adaptation components. We found that the contrast gain reduction showed a frequency dependent increase after octopamine stimulation. Since the contrast gain is non-directional, it is likely presynaptic to the LPTC. We therefore believe that octopamine acts on the delay filter in the EMD. In the third paper we describe a novel LPTC. The centrifugal stationary inhibited flicker excited (cSIFE) is excited by flicker and inhibited by stationary patterns. Neither of these responses can be predicted by EMD models. Therefore, we provide a new type of motion detector that can explain cSIFE’s responses (Paper III). During bar tracking, self-generated optic flow may counteract the steering effect by inducing a contradictory optomotor response. Behavior shows that during bar fixation, flies ignore background optic flow. Our study (Paper IV) focus on the different receptive fields of two LPTCs, and relate these to the bar fixation behavior. In the neuron with a small and fronto-dorsal receptive field, we find a higher correlation with bar motion than with background motion. In contrast, the neuron with a larger receptive field shows a higher correlation with background motion.
6

The processing of natural images in the visual system

Dyakova, Olga January 2017 (has links)
Any image can be described in terms of its statistics (i.e. quantitative parameters calculated from the image, for example RMS-contrast, the skewness of image brightness distribution, and slope constant of an average amplitude spectrum). It was previously shown that insect and vertebrate visual systems are optimised to the statistics common among natural scenes. However, the exact mechanisms of this process are still unclear and need further investigation. This thesis presents the results of examining links between some image statistics and visual responses in humans and hoverflies. It was found that while image statistics do not play the main role when hoverflies (Eristalis tenax and Episyrphus balteatus) chose what flowers to feed on, there is a link between hoverfly (Episyrphus balteatus) active behaviours and image statistics. There is a significant difference in the slope constant of the average amplitude spectrum, RMS contrast and skewness of brightness distribution between photos of areas where hoverflies were hovering or flying. These photos were also used to create a prediction model of hoverfly behaviour. After model validation, it was concluded that photos of both the ground and the surround should be used for best prediction of behaviour. The best predictor was skewness of image brightness distribution. By using a trackball setup, the optomotor response in walking hoverflies (Eristalis tenax) was found to be influenced by the slope constant of an average amplitude spectrum.  Intracellular recording showed that the higher-order neuron cSIFE (The centrifugal stationary inhibited flicker excited) in the hoverfly (Eristalis tenax) lobula plate was inhibited by a range of natural scenes and that this inhibition was strongest in a response to visual stimuli with the slope constant of an average amplitude spectrum of 1, which is the typical value for natural environments.  Based on the results of psychophysics study in human subjects it was found that sleep deprivation affects human perception of naturalistic slope constants differently for different image categories (“food” and “real world scenes”). These results help provide a better understanding of the link between visual processes and the spatial statistics of natural scenes.
7

Fauna insekata polinatora u Vojvodini: diverzitet, brojnost i procena vrednosti ekosistemske usluge polinacije / Fauna of insect pollinators in Vojvodina: diversity, abundance and valuation of ecosystem service of pollination

Markov Zlata 15 May 2017 (has links)
<p>Istraživanje faune insekata opra&scaron;ivača(Hymenoptera: Apoidea i Diptera: Syrphidae) u<br />Vojvodini je rezultiralo registrovanjem 238 vrsta iz 7 familija na četiri tipa zemlji&scaron;nog<br />pokrivača klasifikovanih po CORINE nomenklaturi&nbsp; (2.1.1.&nbsp; -&nbsp; Nenavodnjavan oobradivo zemlji&scaron;te, 2.4.3.&nbsp; -&nbsp; Pretežno poljoprivredna zemlji&scaron;ta sa većim područjima prirodne vegetacije,&nbsp; 3.1.1.&nbsp; -&nbsp; Listopadne &scaron;ume&nbsp; i 3.2.1. - Prirodni travnjaci). Po broju&nbsp; zabeleženih vrsta izdvaja se pokrivač&nbsp; Listopadne &scaron;ume (158).&nbsp; Na prirdonim&nbsp; travnjacima nađeno je 124 vrste, na poluprirodnim stani&scaron;tima 62 i najmanji broj vrsta registrovan je na poljoprivrednim područjima (8).&nbsp; Nova&nbsp; vrsta&nbsp; za&nbsp; nauku&nbsp;<em> Eumerus pannonicus</em>&nbsp; sp.&nbsp; nov.&nbsp; Ricarte,&nbsp; Vujić&nbsp; i Radenković,&nbsp; zabeležena&nbsp; je&nbsp; na&nbsp; lokalitetu Pa&scaron;njaci velike droplje u okviru klase 3.2.1.</p><p>Shannon-ov indeks diverziteta je najveći za Listopadne &scaron;ume (3,385). Za Prirodne travnjake indeks diverziteta je 3,022. Vrednost indeksa za poluprirdona stani&scaron;ta je 2.431, dok je za poljoprivredna područja najmanji (0.765). Shannon-ov indeks diverziteta je računat i za svaki lokalitet&nbsp;&nbsp; posebno.</p><p>Prema&nbsp; Jaccard-ovom&nbsp; koeficijentu&nbsp; sličnosti,najsličnije&nbsp; su&nbsp; faune&nbsp; Slanog&nbsp; Kopova&nbsp; i&nbsp; Pa&scaron;njaka velike&nbsp; droplje&nbsp; (32,7%). Najmanju sličnost pokazala je fauna lokaliteta Đurđevo u kombinaciji sa faunama Fru&scaron;ke gore, Vr&scaron;ačkih planina I, Okanj bare i Vr&scaron;ačkih planina II, gde su svi koeficijenti imali vrednost ispod 4%.</p><p>Na&nbsp; području&nbsp; Vojvodine&nbsp; tri&nbsp; nađene&nbsp; vrste&nbsp; iz&nbsp; reda Hymenoptera&nbsp; uvr&scaron;tene&nbsp; su&nbsp; na&nbsp; IUCN-ovu&nbsp; crvenu listu. Prema nacionalnom Pravilniku o progla&scaron;enju i za&scaron;titi strogo za&scaron;tićenih i za&scaron;tićenih divljih vrsta biljaka, životinja i gljiva, iz kategorije strogo za&scaron;tićenih vrsta nađena je jedna, a od za&scaron;tićenih vrsta nađene su dve osolike muve.</p><p>RDA&nbsp; analizom&nbsp; pokazano&nbsp; je&nbsp; da&nbsp; su&nbsp;&nbsp; statistički značajne&nbsp; sve&nbsp; ispitivane&nbsp; varijable:&nbsp; ko&scaron;enje,&nbsp; UOP(udaljenost&nbsp; od&nbsp; poljoprivrednih&nbsp; područja),nadmorska visina i ispa&scaron;a.</p><p>Ekonomska vrednost ekosistemske usluge polinacije procenjena za period od 2009-2014.godine pokazuje rastući trend. Vrednost polinacije tokom&nbsp; godina rasla je sa 110,5miliona EUR u 2009. godini do 203,7 miliona EUR u 2014.</p> / <p>Research of pollinators fauna&nbsp; (Hymenoptera: Apoidea i Diptera: Syrphidae) in&nbsp; Vojvodina results in a finding of 238 species within 7 families on 4 CORINE land&nbsp; cover habitat types (2.1.1.&nbsp; -&nbsp; Non-irrigated arable&nbsp; land, 2.4.3.&nbsp; -&nbsp; Land principally occupied by agriculture, with significant areas of natural vegetation, 3.1.1. &nbsp;- Broad- leaved forest and 3.2.1.&nbsp; -&nbsp; Natural grasslands). The highest number of species has been recorded on class Broad-leaved forest (158). On class Natural grasslands were found 124 species, on the seminatural habitats 62 species and the lowest&nbsp; number was registered on arable&nbsp; land (8). New species for science Eumerus&nbsp; pannonicus&nbsp; sp.nov.&nbsp; Ricarte,&nbsp; Vujić&nbsp; i Radenković has been recorded in locality Pa&scaron;njaci velike droplje within the class 3.2.1.</p><p>Broad-leaved forest class have&nbsp; the highest values for the scored&nbsp; diversity index (3,385), followed by&nbsp; Natural grasslands (3,022) and saminatural habitats (2,431). Arable land class have&nbsp; the lowest diversity values, only 0,765. The Shannon diversity index is calculated for each locality.</p><p>According to Jaccard similarity coefficient, Slano Kopovo and Pa&scaron;njaci Velike Droplje have shown to be most similar faunistically (32,7%). The fauna of Djurdjevo had the lowest similarity value comparing to faunas of Fruska gora, Vrsacke planine I, Okanj bara and Vrsacke planine II, where all the coefficients were below 4%.</p><p>Two of the 238&nbsp; recorded bee species in Vojvodina are included in the IUCN red list. Acording to Serbian&nbsp; regulatory&nbsp; act&nbsp; &bdquo;Regulation on the promulgation and protection of the protected and strictly protected wild species of plants,&nbsp; animals and fungi&ldquo; one&nbsp; Syrphidae species&nbsp; is catalogued as a Strictly Protected,while two found hoverflie species are Protected. RDA analysis has demonstrated that all the environmental variables used for the analysis are of statistical significance: mowing, UOP(distance from the agricultural area), elevation and grazing intensity.</p><p>Economic value of insect pollination was estimated for&nbsp; a length of&nbsp; time 2009.-2014., and displays&nbsp; an&nbsp; increasing&nbsp; trend.The value of pollination&nbsp; has increased&nbsp; over these years, starting with 110,5 millions of EUR in 2009., up to 203,7 millions of EUR in 2014.</p>
8

Molecular phylogeny and evolution of predatory Syrphidae (Insecta: Diptera)

Mengual Sanchis, Ximo 12 June 2008 (has links)
No description available.
9

Genetička karakterizacija kompleksa Merodon avidus (Diptea: Syrphidae) / Genetic characterisation of Merodon avidus species complex (Diptera: Syrphidae)

Popović Dunja 15 October 2019 (has links)
<p>U&nbsp; radu&nbsp; je&nbsp; izvr&scaron;en&nbsp; integrativno-taksonomski&nbsp; pristup analize&nbsp; kompleksa&nbsp; vrsta&nbsp; <em>Merodon</em>&nbsp; <em>avidus&nbsp; </em>(Diptera: Syrphidae),&nbsp; na&nbsp; geografski&nbsp; i&nbsp; vemenski&nbsp; obimnom materijalu.&nbsp; U&nbsp; okviru&nbsp; genetičke&nbsp; karakterizacije&nbsp; kriptičnih vrsta&nbsp; navedenog&nbsp; kompleksa,&nbsp; bazirane&nbsp; na&nbsp; 3&#39;&nbsp; i&nbsp; 5&#39;<br />fragmentima&nbsp; mitohondrijalnog&nbsp; COI&nbsp; gena,&nbsp; određeni&nbsp; su parametri&nbsp; genetičke&nbsp; varijabilnosti&nbsp; i&nbsp; utvrđeni&nbsp; jedinstveni&nbsp; i deljeni&nbsp; haplotipovi&nbsp; u&nbsp; okviru&nbsp; i&nbsp; između&nbsp; pretpostavljenih vrsta.&nbsp; Rezultati&nbsp; genetičke&nbsp; varijabilnosti&nbsp; COI&nbsp; DNK&nbsp; sekvenci pokazali&nbsp; su&nbsp; da&nbsp; jedinke&nbsp; sa&nbsp; ostrva&nbsp; Krf&nbsp; i&nbsp; Evia&nbsp; i&nbsp; poluostrva Peloponez,&nbsp; preliminarno&nbsp; identifikovane&nbsp; kao M. moenium, predstavljaju&nbsp; novu,&nbsp; endemsku&nbsp; vrstu&nbsp; proučavanog<br />kompleksa.&nbsp; Dijagnostički&nbsp; enzimski&nbsp; lokusi&nbsp; pokazali&nbsp; su&nbsp; da M.&nbsp; avidus&nbsp; i&nbsp; M.&nbsp; moenium&nbsp; predstavljaju&nbsp; sestrinske&nbsp; vrste, koje&nbsp; su&nbsp; se,&nbsp; u&nbsp; okviru&nbsp; kompleksa&nbsp; vrsta&nbsp;<em> M.&nbsp; avidus,&nbsp; </em>poslednje razdvojile.&nbsp; Zaključeno&nbsp; je&nbsp; da&nbsp; se&nbsp; kompleks&nbsp; vrsta&nbsp; M.&nbsp; avidus sastoji od 5 vrsta: <em>M. avidus, M. moenium, M. megavidus, M.&nbsp; ibericus&nbsp; i&nbsp; M.&nbsp; aff.&nbsp; moenium</em>.&nbsp; U&nbsp; nastavku,&nbsp; oslanjajući&nbsp; se na&nbsp; moderne&nbsp; tehnike&nbsp; ve&scaron;tačke&nbsp; inteligencije,&nbsp; izvr&scaron;eno&nbsp; je modelovanje&nbsp; distribucije&nbsp; vrsta&nbsp; i&nbsp; poređenje&nbsp; sličnosti utvrđenih&nbsp; ekolo&scaron;kih&nbsp; ni&scaron;a.&nbsp; U&nbsp; poslednjem&nbsp; segmentu istraživanja,&nbsp; prednosti&nbsp; ve&scaron;tačke&nbsp; inteligencije&nbsp; iskori&scaron;ćene su&nbsp; u&nbsp; modelovanju&nbsp; sistema&nbsp; za&nbsp; determinaciju&nbsp; jedinki sestrinskih vrsta u uzorku, na osnovu adekvatne varijable.Ovo&nbsp; istraživanje&nbsp; doprinelo&nbsp; je&nbsp; karakterizaciji&nbsp; biodiverziteta osolikih&nbsp; muva,&nbsp; rasvetljavanju&nbsp; taksonomskog&nbsp; statusa&nbsp; vrsta i&nbsp; kreiranju&nbsp; smernica&nbsp; za&nbsp; definisanje&nbsp; budućih konzervacionih&nbsp; programa&nbsp; za&scaron;tite&nbsp; biodiverziteta&nbsp; vrsta <em>Merodon avidus </em>kompleksa.</p> / <p>During this research, an integrative-taxonomic&nbsp; analysis of M. avidus species complex was performed. The study was based on geographically and temporally extensive material. Genetic characterisation of cryptic species, based on 5&rsquo; and 3&rsquo; regions of COI gene, defined parameters of genetic variability. Shared and unique haplotypes between and within of cryptic species were detected. The results of genetic variability analysis based on COI gene showed that specimens from the islands Corfu, Evia and half-island Peloponnese, which were preliminarily identified as M. moenium, represent a new, endemic species of the selected complex. Diagnostic enzyme loci showed that M. avidus and M. moenium represent sibling species, which were the last one who separated within M. avidus complex. According to current information, it was concluded that M. avidus complex consists of 5 species: M. avidus, M. moenium, M. megavidus, M. ibericus and M. aff. moenium. In the next&nbsp; chapter, relying on modern techniques of artificial&nbsp; intelligence, the species distribution modelling and the comparison of ecological niches were performed. In the last part of the research, the advantages of artificial intelligence were used in order to model a system that was able to determinate one of two sibling species, based on appropriate predictor. This research has generally contributed to a characterization of hoverfly diversity and helped resolving a taxonomic status of species in one of the most challenging groups in Syrphidae family. Genetic differentiation data represent directions for defining future conservation strategies for biodiversity protection of defined cryptic species of Merodon avidus complex</p>
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Reprodukční biologie \kur{Achillea millefolium} agg. a \kur{Achillea ptarmica} v lučních a lemových společenstvech / Reproduction of \kur{Achillea millefolium} agg. and \kur{Achillea ptarmica} in meadows and verges

TOMŠOVÁ, Pavla January 2013 (has links)
Several changes in land use during the last 50 years of 20th century had a significant impact on the composition of traditional meadows. The abundance of many plant species typical for traditionally managed meadows has declined. But some of these species have found a refuge in habitats such as field margins and road verges. The aim of this study was to describe how the reproduction success of two related Achillea species A. millefolium agg. and A. ptarmica depends on (i) the particular habitat in which they grow (meadow/verge); (ii) the abundance of pollinators in the study site; and (iii) timing of flowering within the season. Moreover, the longevity of individual flowers of the two taxa has been studied in order assess the width of the time frame the reproduction takes place in. These objectives were achieved by means of measuring plant total seed production and germination as proxies of reproductive success both in meadow and verge populations at the beginning, peak and end of the flowering season of the two species in 2012. The plants were chosen at plots, where concurrently a pollinator survey has been conducted as the part of the broader project. The durations of the male and female phases of individual flowers have been studied in separate experiments.

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