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722. Succession in ant communities (Hymenoptera: Formicidae) in deciduous forest clear-cuts - an Eastern European case study
- Creator:
- Tăuşan, Ioan, Dauber, Jens, Trică, Maria R., and Markó, Bálint
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, blanokřídlí, mravencovití, opadavé lesy, Hymenoptera, ants, deciduous forests, Formicidae, secondary succession, clear-cutting, community structure, pitfall traps, 2, and 59
- Language:
- English
- Description:
- Clear-cutting, the main method of harvesting in many forests in the world, causes a series of dramatic environmental changes to the forest habitat and removes habitat resources for arboreal and epigeal species. It results in considerable changes in the composition of both plant and animal communities. Ants have many critical roles in the maintenance and functioning of forest ecosystems. Therefore, the response of ants to clear-cutting and the time it takes for an ant community to recover after clear-cutting are important indicators of the effect of this harvesting technique on the forest ecosystem. We investigated ground-dwelling ant communities during secondary succession of deciduous forests in Transylvania, Romania. Using space-for-time substitution, we explored a chronosequence from clear-cuts to mature forests (> 120 years). The object was to determine if cutting has measurable effects on ant community structure, and if ant species richness differs between successional stages. We recorded a total of 24 species of ants, 11 characteristic of forests and seven of open landscape. Ant species richness was higher in clear-cuts compared to closed-canopy and old stands. Number of ant individuals was highest in young age classes and lowest in closed-canopy age classes. There was no drastic change in species richness during the succession, however differences in community composition at different stages were recorded. Open landscape species are able to rapidly colonize following disturbance but disappear when the forest sites mature and many forest ant species are capable of surviving clear cutting., Ioan Tăuşan, Jens Dauber, Maria R. Trică, Bálint Markó., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
723. Sucho na území České republiky
- Creator:
- Jaroslav Rožnovský
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, ekologie, ecology, životní prostředí, environment, Česko, 2, and 59
- Language:
- Czech
- Description:
- Průběh počasí a v dlouhodobém pohledu podnebí patří k limitujícím podmínkám pro výskyt organismů, dokladem je výskyt teplomilných a naopak i chladnomilných nebo suchomilných a mokřadních druhů na našem území. A nejde pouze o přirozená společenstva, rozdíly nacházíme i ve skladbě pěstovaných plodin. Plošnou proměnlivost ovlivňují rozdílné klimatické podmínky - kromě podnebí hrají roli také půdní vlastnosti, které i díky odlišným geologickým podmínkám jsou velmi různorodé. Podnebí je však nejdynamičtější složkou přírodního prostředí. A právě pro území České republiky je typická vysoká proměnlivost podnebí i počasí v čase. Sucho se v posledních letech vyskytuje stále častěji, což však není dáno pouze nedostatkem srážek, ale také schopností krajiny zadržet vodu. Označení „sucho“ je výraz v obecném pojetí dosti neurčitý a v různých vědních i hospodářských oborech odlišně definovaný. Sucho meteorologické je nejčastěji vyjádřené časovými a prostorovými deficity srážek, které představují prvotní příčiny výskytu tohoto jevu. Kromě množství a intenzity spadlých srážek vztažených k dlouhodobým srážkovým úhrnům pro dané místo a roční dobu stanovili mnozí autoři různé definice sucha, a to v závislosti i na dalších klimatologických prvcích (teplota vzduchu, výpar, rychlost větru, vlhkost vzduchu aj.). Sucho zemědělské (agronomické) je vyjádřeno nedostatkem vody v půdě pro zemědělské plodiny ovlivněným předchozím nebo stále trvajícím výskytem meteorologického sucha. Z hlediska vodních poměrů v krajině je pak důležité sucho hydrologické. Člověk svou činností ovlivňuje krajinu, což platí i pro území ČR, kde může časem nastat nedostatek vody, a proto bychom se při hospodaření v krajině měli zaměřit, Climate has a substantial influence on the occurrence of organisms and thanks to its high variability various communities are to be found on our territory. The last years have seen increasingly frequent extreme climatic events, including the occurrence of serious drought. To assess the occurrence of drought the moisture balance method (difference between total precipitation and potential evapotranspiration) is the most frequently used. The extent and intensity of drought also depend on water retention capacity of the landscape. In view of possible climate change (particularly increase in air temperature), more pronounced drought periods may occcur in the near future., and Jaroslav Rožnovský.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
724. Survey and DNA barcoding of flat bugs (Hemiptera: Aradidae) in the Tanzanian Forest Archipelago reveal a phylogeographically structured fauna largely unknown at the species level
- Creator:
- Grebennikov, Vasily V and Heiss, Ernst
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- ploštice, fylogeografie, Heteroptera, phylogeography, Tanzanie, Tanzania, Aradidae, Mezirinae, microptery, barcoding, Eastern Arc Mountains, 2, and 59
- Language:
- English
- Description:
- We report results of a faunal survey of Aradidae flat bugs sampled by sifting litter in 14 wet and discrete Tanzanian primary forests (= Tanzanian Forest Archipelago, TFA) of different geological origins and ages. Images, locality data and, when available, DNA barcoding sequences of 300 Aradidae adults and nymphs forming the core of the herein analyzed data are publicly available online at dx.doi.org/10.5883/DS-ARADTZ. Three Aradidae subfamilies and seven genera were recorded: Aneurinae (Paraneurus), Carventinae (Dundocoris) and Mezirinae (Afropictinus, Embuana, Linnavuoriessa, Neochelonoderus, Usumbaraia); the two latter subfamilies were also represented by specimens not assignable to nominal genera. Barring the six nominal species of Neochelonoderus and Afropictinus described earlier by us from these samples and representing 11 of the herein defined Operational Taxonomic Units (OTU), only one of the remaining 52 OTUs could be assigned to a named species; the remaining 51 OTUs (81%) represent unnamed species. Average diversity of Aradidae is 4.64 species per locality; diversity on the three geologically young volcanoes (Mts Hanang, Meru, Kilimanjaro) is significantly lower (1.33) than on the nine Eastern Arc Mountains (5.67) and in two lowland forests (5). Observed phylogeographic structure of Aradidae in TFA can be attributed to vicariance, while the depauperate fauna of Aradidae on geologically young Tanzanian volcanoes was likely formed anew by colonisation from nearby and geologically older forests., Vasily V. Grebennikov, Ernst Heiss., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
725. Surveying abundance and stand type associations of Formica aquilonia and F. lugubris (Hymenoptera: Formicidae) nest mounds over an extensive area: trialing a novel method
- Creator:
- Borkin, Kerry M., Summers, Ron W., and Thomas, Len
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Formicidae, distance sampling, Formica, line transect, old-growth, Pinus sylvestris, Scotland, 2, and 59
- Language:
- English
- Description:
- 1_Red wood ants are ecologically important members of woodland communities, and some species are of conservation concern. They occur commonly only in certain habitats in Britain, but there is limited knowledge of their numbers and distribution. This study provided baseline information at a key locality (Abernethy Forest, 37 km2) in the central Highlands of Scotland and trialed a new method of surveying red wood ant density and stand type associations: a distance sampling line transect survey of nests. This method is efficient because it allows an observer to quickly survey a large area either side of transect lines, without having to assume that all nests are detected. Instead, data collected on the distance of nests from the line are used to estimate probability of detection and the effective transect width, using the free software "Distance". Surveys took place in August and September 2003 along a total of 71.2 km of parallel, equally-spaced transects. One hundred and forty-four red wood ant nests were located, comprising 89 F. aquilonia (Yarrow, 1955) and 55 F. lugubris (Zetterstedt, 1838) nests. Estimated densities were 1.13 nests per hectare (95% CI 0.74–1.73) for F. aquilonia and 0.83 nests per hectare (95% CI 0.32–2.17) for F. lugubris. These translated to total estimated nest numbers of 4,200 (95% CI 2,700–6,400) and 3,100 (95% CI 1,200–8,100), respectively, for the whole forest. Indices of stand selection indicated that F. aquilonia had some positive association with old-growth and F. lugubris with younger stands (stem exclusion stage). No nests were found in areas that had been clear-felled, and ploughed and planted in the 1970s–1990s. The pattern of stand type association and hence distribution of F. aquilonia and F. lugubris may be due to the differing ability to disperse (F. lugubris is the faster disperser) and compete (F. aquilonia is competitively superior)., 2_We recommend using line transect sampling for extensive surveys of ants that construct nest mounds to estimate abundance and stand type association., Kerry M. Borkin, Ron W. Summers, Len Thomas., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
726. Survival and developmental characteristics of the predatory bug Orius similis (Hemiptera: Anthocoridae) fed on Tetranychus cinnabarinus (Acari: Tetranychidae) at three constant temperatures
- Creator:
- Zhang, Shi-Chang, Zhu, Fen, Zheng, Xia-Lin, Lei, Chao-Liang, and Zhou, Xing-Miao
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hemiptera, Anthocoridae, Orius similis, Acari, Tetranychidae, Tetranychus cinnabarinus, biological control, development characteristics, functional response, 2, and 59
- Language:
- English
- Description:
- Developmental characteristics of the predatory bug Orius similis fed on Tetranychus cinnabarinus were investigated at three constant temperatures (25, 28, and 31°C) under laboratory conditions (75±5% relative humidity and a 14L : 10D photoperiod). The survival of nymphs was highest at 28°C (75.57%) and at this temperature female adults O. similis had the longest oviposition period (21.1 d), the greatest fecundity (40.3 eggs) and the highest potential intrinsic rate of increase (rm: 0.108 d–1). These results suggest that O. similis can maintain greater population densities at 28°C than at the other temperatures tested. In addition, the functional response indicates that the attack rate of O. similis (1.04) and the maximum prey capacity (30.7 spider mites per bug in 24h) are greatest at 28°C. The results of this study provide useful information on the biology and time when to release O. similis in order to reduce the abundance of T. cinnabarinus in cotton fields., Shi-Chang Zhang ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
727. Survival of ground beetles (Coleoptera: Carabidae) submerged during floods: Field and laboratory studies
- Creator:
- Kolesnikov, Felix N., Karamyan, Arevik N., and Hoback, W. Wyatt
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Carabidae, survival time, submergence, flooding, hypoxic conditions, 2, and 59
- Language:
- English
- Description:
- Field and laboratory experiments were conducted to assess the time ground beetles (Coleoptera: Carabidae) survive during actual and simulated flood conditions. The effects of three variants of potential flood conditions were tested: (1) beetles trapped on the surface of flood water; (2) beetles trapped in air pockets; (3) submersion of beetles in flood water without access to air. Ground beetles trapped on the surface of water survived more than two weeks (Carabus granulatus – up to 16 days; Oxypselaphus obscurus – up to 22 days). Carabus granulatus in simulated hibernation chambers that had air-pockets also survived for 15 days. The time for which ground beetles submerged without access to air survived differed significantly among species and was affected by season. They survived longest in mid-spring and late-autumn when water temperature is low. In mid-spring, survival times for C. granulatus and Platynus assimilis were 12 days and 9 days, respectively. During late summer and early autumn all species survived for a shorter period of time. In August, at least half of the individuals tested were dead after three days of immersion (water temperature 16–18°C). Removal of both of the elytra of adult of C. granulatus resulted in them surviving immersion for a shorter period, which indicates that air stored in the sub-elytral cavity is used to prolong the period they can survive immersion. The results of these experiments broaden the knowledge of how adult beetles survive seasonal flooding and are able to persist in floodplain habitats., Felix N. Kolesnikov, Arevik N. Karamyan, W. Wyatt Hoback., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
728. Survival, body mass and potential fecundity of the invasive moth Cameraria ohridella (Lepidoptera: Gracillariidae) on its original host plant Aesculus hippocastanum and Aesculus glabra
- Creator:
- Walczak, Urszula, Baraniak, Edward, and Zduniak, Piotr
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, motýli, vzpřímenkovití, klíněnka jírovcová, butterflies, Gracillariidae, Cameraria ohridella, Lepidoptera, invasive species, leaf miner, herbivore performance, Aesculus hippocastanum, Aesculus glabra, 2, and 59
- Language:
- English
- Description:
- Performance of the invasive horse-chestnut leaf miner, Cameraria ohridella Deschka & Dimic, 1986 (Lepidoptera: Gracillariidae), was studied on two host plants: the white-flowering horse-chestnut Aesculus hippocastanum L. and the Ohio buckeye Aesculus glabra Willd. C. ohridella developed successfully on both host plants; however, mine density and survival were much higher on A. hippocastanum than on A. glabra. The pupal mass and potential fecundity were strongly affected by the host plant on which the larvae fed. On A. hippocastanum pupae were significantly heavier and females more fecund than those on A. glabra. Furthermore, on both host plants there was a significant positive correlation between the number of oocytes in ovaries and pupal body mass, and as a consequence, heavier females produced more eggs. Our study demonstrates that the mine density, survival, pupal mass and potential fecundity were significantly lower on A. glabra than on A. hippocastanum. The observed lower performance of C. ohridella on the exotic host plant was assumed to be due to its poor food quality (nutritional and chemical composition)., Urszula Walczak, Edward Baraniak, Piotr Zduniak., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
729. Svět očima zvířat aneb jak ptáci vnímají barvy
- Creator:
- Šulc, Michal and Marcel Honza
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, ptáci, molekulární biologie, fyziologie, zrak, birds, molecular biophysics, physiology, vision, 2, and 59
- Language:
- Czech
- Description:
- Zbarvení hraje v životě zvířat zásadní roli a je často pod přísným dohledem přírodního a/nebo pohlavního výběru. Abychom mohli objektivně zhodnotit jeho vliv na životní strategie zvířat, je zaprvé důležité barvu správně měřit a zadruhé nahlížet na ni zrakovým aparátem zainteresovaného pozorovatele. Obě tyto metody popisujeme na příkladu ptáků, konkrétně hodnocení mimeze parazitických vajec., Colouration plays a very important role in the life of animals and its evolution is often under natural and/or sexual selection. For objective assessment of the influence of colouration on animal life strategies the colour should be measured properly and evaluated from the perspective of the studied species. These methods are briefly described based on the example of birds, specifically on the mimicry of parasitic eggs., and Michal Šulc, Marcel Honza.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
730. Symbiotic bacteria (Erwinia sp.) in the gut of Frankliniella occidentalis (Thysanoptera: Thripidae) do not affect its ability to transmit tospovirus
- Creator:
- De Vries, Egbert, Van de Wetering, Fennet, Van der Hoek, Marieke M., Jacobs, Gerrit, and Breeuwer, Johannes A.J.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Erwinia, TSWV, virus-bacteria interaction, Frankliniella occidentalis, Thripidae, 2, and 59
- Language:
- English
- Description:
- Tomato spotted wilt virus (TSWV) is one of the most harmful plant viruses and one of its most important vectors is the western flower thrips [Frankliniella occidentalis Pergande (Thysanoptera: Thripidae)]. Recently, we reported the close association of Erwinia sp. gut bacteria with this species of thrips. The first instar larvae acquire these bacteria from their food source. A high proportion of adult western flower thrips transmit TSWV after acquiring the virus during the first larval stage when there are no bacteria in their gut. A considerably lower proportion of adults that acquire the virus early in the second instar transmit virus and none of those exposed to virus late on in the second instar do so. The highest prevalence and total number of symbiotic bacteria are recorded in the guts of second instar thrips. This leads to the hypothesis that the build up of bacteria in the gut reduces the acquisition of TSWV, resulting in a lower capacity to transmit the virus. To test this hypothesis, the transmission of this virus by symbiotic and aposymbiotic adult thrips of the NL3 population was studied. Comparison of virus transmission by adult thrips, the larvae of which either had or lacked gut bacteria and were exposed to virus in either the first or second instar, revealed no difference in the ability of symbiotic and aposymbiotic adults to transmit this virus. We conclude that virus transmission is not affected by the number of the symbiotic bacteria Erwinia sp. present in the gut of thrips larvae., Egbert J De Vries ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public