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1532. Vzácní brouci na ostravských haldách - mají rekultivace odvalů vůbec smysl?
- Creator:
- Hodeček, Jiří and Tomáš Kuras
- Format:
- bez média and svazek
- Type:
- article, text, články, journal articles, model:article, and TEXT
- Subject:
- Životní prostředí a jeho ochrana, krajinná ekologie, odvaly, rekultivace, hornická krajina, ekologická sukcese, bezobratlí, brouci, soil remediation, landscape ecology, mine dumps, mining landscape, ecological succession, beetles, invertebrates, ostravsko-karvinská pánev (Česko), Ostrava-Karviná coal basin (Czechia), spontánní sukcese, spontaneous succession, spoil heaps, 2, and 502
- Language:
- Czech
- Description:
- Haldy (odvaly), které na Ostravsku vznikaly jako průvodní jev dolování černého uhlí v první polovině 20.stol, se již staly typickým krajinným prvkem této oblasti. Později zde byly snahy dolováním pozměněnou krajinu „uzdravit“ finančně nákladnými technickými rekultivacemi. Výstupy z našich studií prokázaly, že spontánní sukcese na nerekultivovaných haldách probíhá rychleji a společenstva bezobratlých jsou zde lépe strukturovaná. Navíc nerekultivované haldy podporují populace ochranářsky cenných druhů bezobratlých. Jednoznačně proto doporučujeme haldy ponechat spontánní sukcesi, před finančně náročnými technicky vedenými rekultivacemi., The spoil heaps in Ostrava were created during mining of black coal in the first half of the 20th century. Later, there were efforts to “heal” the landscape by technical reclamations, which are rather expensive. Our studies showed that spontaneous succession on non-reclaimed spoil heaps is faster then succession on their reclaimed counterparts. The communities of invertebrates on non-reclaimed spoil heaps are also more mature and contain rare species in comparison with the reclaimed ones., and Jiří Hodeček, Tomáš Kuras.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1533. Vzpomenutí na odkaz Jaroslava Slípky
- Creator:
- Petr Šíma
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, Slípka, Jaroslav, 1926-2013, zoologie, 2, and 59
- Language:
- Czech
- Description:
- Petr Šíma.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1534. Vzpomínka na Evžena Balona
- Creator:
- Vladimír Hanák
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, Balon, Eugene, 1930-2013, zoologie, 2, and 59
- Language:
- Czech
- Description:
- Vladimír Hanák.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1535. Vzpomínka na Otu Olivu
- Creator:
- Miroslav Švátora
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, Oliva, Ota, 1926-1994, zoologie, 2, and 59
- Language:
- Czech
- Description:
- Miroslav Švátora.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1536. Vztahy rostlin a opylovačů na louce aneb nejen botanici určují rostliny
- Creator:
- Janovský, Zdeněk
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, rostliny, opylovači, rostlinná společenstva, 2, and 59
- Language:
- Czech
- Description:
- The honey bee is usually thought of as a key pollinator in cultural landscapes. Our results evidence that although it may be the most abundant, its importance is lower compared to hoverflies and bumblebees both in terms of the pollinated plant species number and the spectrum of vegetation types covered. The broad spectrum of hoverfly diets suggests the cause of their high importance as pollinators. and Zdeněk Janovský.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1537. Warp-speed adaptation to novel hosts after 300 generations of enforced dietary specialisation in the seed beetle Callosobruchus maculatus (Coleoptera: Chrysomelidae: Bruchinae)
- Creator:
- Price, Thomas N., Leonard, Aoife, and Lancaster, Lesley T.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, mandelinkovití, beetles, Chrysomelidae, Coleoptera, Bruchinae, Callosobruchus maculatus, emerging crop pests, host shifts, genetic variation, adaptation trajectory, evolvability, experimental evolution, quasi-natural selection, heritability, 2, and 59
- Language:
- English
- Description:
- Herbivorous insects are often highly specialised, likely due to trade-offs in fitness on alternative host species. However, some pest insects are extremely adaptable and readily adopt novel hosts, sometimes causing rapid expansion of their host range as they spread from their original host and geographic origin. The genetic basis of this phenomenon is poorly understood, limiting our ability to predict or mitigate global insect pest outbreaks. We investigated the trajectory of early adaptation to novel hosts in a regionally-specialised global crop pest species (the cowpea seed beetle Callosobruchus maculatus). After experimentally-enforced dietary specialisation for nearly 300 generations, we measured changes in fitness over the first 5 generations of adaptation to 6 novel hosts. Of these, C. maculatus reproduced successfully on all but one, with reduced fitness observed on three hosts in the first generation. Loss of fitness was followed by very rapid, decelerating increases in fitness over the first 1-5 generations, resulting in comparable levels of population fitness to that observed on the original host after 5 generations. Heritability of fitness on novel hosts was high. Adaptation occurred primarily via changes in behavioural and phenological traits, and never via changes in offspring survival to adulthood, despite high heritability for this trait. These results suggest that C. maculatus possesses ample additive genetic variation for very rapid host shifts, despite a prolonged period of enforced specialization, and also suggest that some previously-inferred environmental maternal effects on host use may in part actually represent (rapidly) evolved changes. We highlight the need to examine in more detail the genetic architecture facilitating retention of high additive genetic variation for host shifts in extremely adaptable global crop pests., Thomas N. Price, Aoife Leonard, Lesley T. Lancaster., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1538. Water relations and gas exchange in Coespeletia moritziana (Sch. Bip) Cuatrec., a giant rosette species of the high tropical Andes
- Creator:
- Rada, F., Azócar, A., and Rojas-Altuve, A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, net photosynthetic rate, osmotic adjustment, plant growth stages, stomatal conductance, tropical mountains, 2, and 58
- Language:
- Multiple languages
- Description:
- Giant rosettes are ones of the most striking features of the vegetation in the high tropical Andes, with Coespeletia moritziana reaching the highest altitudes up to 4,600 m a.s.l. Different from other giant rosettes, this species grows on rock outcrops with poorly developed soils and where water availability may be limited. Two questions are addressed in this study: How does this species respond in terms of water relations to maintain favorable gas-exchange conditions? Considering that adult plants rely on a water-reserving central pith, how do early stages respond to this environment’s extreme conditions? Water relations and gas-exchange studies were carried out on juveniles, intermediate and adult C. moritziana plants during wet and dry seasons in Páramo de Piedras Blancas at 4,200 m a.s.l. Adult plants maintained higher leaf water potentials (ΨL) during the wet season, however, no differences between stages were found for the dry season. Minimum dry season ΨL were never near the turgor loss point in any of the stages. Juveniles show a more strict stomatal control during the dry season to maintain a favorable water status. Net photosynthesis significantly decreased in intermediate and juvenile stages from wet to dry seasons. Our results suggest that C. moritziana resists more extreme conditions compared to other Andean giant rosettes., F. Rada, A. Azócar, A. Rojas-Altuve., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1539. Water stress and abscisic acid treatments induce the CAM pathway in the epiphytic fern Vittaria lineata (L.) Smith
- Creator:
- Minardi, B. D., Voytena, A. P. L., Santos, M., and Randi, Á. M.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, pigmenty, photosynthesis, pigments, Brazílie, Brasil, chlorophyll fluorescence, malate, morphoanatomy, photosynthetic pathway, Vittaria lineata, 2, and 581
- Language:
- Multiple languages
- Description:
- Among various epiphytic ferns found in the Brazilian Atlantic Forest, we studied Vittaria lineata (L.) Smith (Polypodiopsida, Pteridaceae). Anatomical characterization of the leaf was carried out by light microscopy, fluorescence microscopy, and scanning electron microscopy. V. lineata possesses succulent leaves with two longitudinal furrows on the abaxial surface. We observed abundant stomata inside the furrows, glandular trichomes, paraphises, and sporangia. We examined malate concentrations in leaves, relative water content (RWC), photosynthetic pigments, and chlorophyll (Chl) a fluorescence in control, water-deficient, and abscisic acid (ABA)-treated plants. Plants subjected to drought stress (DS) and treated by exogenous ABA showed significant increase in the malate concentration, demonstrating nocturnal acidification. These findings suggest that V. lineata could change its mode of carbon fixation from C3 to the CAM pathway in response to drought. No significant changes in RWC were observed among treatments. Moreover, although plants subjected to stress treatments showed a significant decline in the contents of Chl a and b, the concentrations of carotenoids were stable. Photosynthetic parameters obtained from rapid light curves showed a significant decrease after DS and ABA treatments., B. D. Minardi, A. P. L. Voytena, M. Santos, Á. M. Randi., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1540. Water-deficiency effects on single leaf gas exchange and on C4 pathway enzymes of maize genotypes with differing abiotic stress tolerance
- Creator:
- Sicher, Richard, Bunce, J., Barnaby, J., and Bailey, B.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, sucha, kukuřice, photosynthesis, C4 photosynthesis, drought, enzyme activities, gene expression, phosphoenolpyruvate carboxylase, maize, abiotic stress, 2, and 581
- Language:
- Multiple languages
- Description:
- Responses to drought were studied using two maize inbred lines (B76 and B106) and a commercial maize hybrid (Zea mays L. cv. Silver Queen) with differing resistance to abiotic stress. Maize seedlings were grown in pots in controlled environment chambers for 17 days and watering was withheld from one half the plants for an additional 11 days. On the final treatment date, leaf water potentials did not differ among genotypes and were -0.84 and -1.49 MPa in the water sufficient and insufficient treatments, respectively. Greater rates of CO2 assimilation were retained by the stress tolerant maize inbred line, B76, in comparison to the other two genotypes 11 days after watering was withheld. Rates of CO2 assimilation for all three genotypes were unaffected by decreasing the measurement O2 concentration from 21 to 2% (v/v). Activities of phosphoenolpyruvate carboxylase (PEPC), NADP-malic enzyme (NADP-ME), and NADP malate dehydrogenase were inhibited from 25 to 49% by the water deficiency treatment. Genotypic differences also were detected for the activities of NADP-ME and for PEPC. Changes of transcript abundance for the three C4 pathway enzymes also varied among watering treatments and genotypes. However, examples where transcripts decreased due to drought were associated with the two stress susceptible genotypes. The above results showed that enzymes in the C4 photosynthetic pathway were less inhibited by drought in stress tolerant compared to stress susceptible maize genotypes., R. Sicher, J. Bunce, J. Barnaby, B. Bailey., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public