Fourteen species (twelve adult and two larval) of nematodes belonging to the Ascaridoidea, Camallanoidea, Cosmocercoidea, Habronematoidea, Oxyuroidea, Seuratoidea and Trichinelloidea were collected from fishes in the Sudan (River Nile and Atbara Dam Lake), whereas only four species (one adult and three larval) of the Ascaridoidea, Camallanoidea, Dioctophymatoidea and Trichinelloideafrom fishes in Ethiopia (Lake Tana). The Sudanese material also contained two previously unknown species, Cucullanus mormyri sp. n. from Mormyrus caschive Linnaeus (type host), Mormyrus sp. and Marcusenius cyprinoides (Linnaeus) (all Mormyridae), and Procamallanus (Spirocamallanus) pseudospiralis sp. n. from Synodontis schall (Bloch et Schneider) (type host), S. frontosus Vaillant and S. nigrita Valenciennes (all Mochokidae), which are described based on light and scanning electron microscopical studies. Cucullanus baylisi Campana-Rouget, 1961, a little-known parasite of Synodontis spp., is redescribed in detail. A key to Procamallanus (Spirocamallanus) spp. from African inland fishes is provided. Falcaustra guiersi Vassiliadès, 1973 is considered a junior synonym of F. hexapapillata (Khalil, 1962). The findings represent several new host and geographical records. Cucullanus baylisi Lakshmi, 2000 (= a homonym to C. baylisi Campana-Rouget, 1961) is re-named as C. dubius nom. n. and is considered a species inquirenda., František Moravec, Tomáš Scholz., and Obsahuje bibliografii
V článku je krátce popsán dopad výbuchu na přírodu a hlavně vegetaci a je charakterizována spontánní sukcese vegetace, která poté následovala. Zdůrazněny jsou rozdíly mezi primární a sekundární sukcesí a zmíněny jsou hlavní mechanismy a faktory, které sukcesi ovlivňují. Článek vychází z terénní zkušenosti autora s lokalitou a z výsledků dlouhodobého výzkumu sukcese vedeného americkými ekology., V článku je krátce popsán dopad výbuchu na přírodu a hlavně vegetaci a je charakterizována spontánní sukcese vegetace, která poté následovala. Zdůrazněny jsou rozdíly mezi primární a sekundární sukcesí a zmíněny jsou hlavní mechanismy a faktory, které sukcesi ovlivňují. Článek vychází z terénní zkušenosti autora s lokalitou a z výsledků dlouhodobého výzkumu sukcese vedeného americkými ekology., and Karel Prach.
Czech botanists have participated in research into the taxonomy, diversity and ecology of plants in the equatorial high Andes since the mid 90s. The results include a description of new species of vascular plants and lichens, a contribution to generic flora, one monography and publication of several dozen original papers. and Petr Sklenář.
The virgin forests of the Krkonoše Mts. have been transformed into less stable spruce monocultures due to economic activities in the past. The objective of the current management of forest ecosystems is to create a compact core area of a sufficient size capable of autoregulation processes. Surrounding areas should be managed in ways that protect and conserve native biodiversity. Conservation efforts should be coordinated between the Czech and Polish sides of the Krkonoše Mts. and Otakar Schwarz.
Korbikula asijská (Corbicula fluminea) je jedním z nepůvodních a zároveň invazních druhů mlžů, které postupně dobývají území Evropy včetně České republiky. Korbikula pochází z jihovýchodní Asie, odkud byla introdukována zřejmě asijskými přistěhovalci do Severní Ameriky a z té po několika desítkách let (kolem r. 1980) doputovala lodní dopravou (pravděpodobně s balastní vodou) do Evropy. Na naše území pronikla Labem z Německa a byla zde poprvé zjištěna v r. 1999. V současnosti je známa z Labe, prozatím po Týnec nad Labem. Byla však již zaznamenána také v dolním toku Vltavy (po Nelahozeves, včetně plavebního kanálu Vraňany – Hořín) a Ohře (po Terezín) a překvapivě pozorována v některých menších přítocích Labe, jakým je např. potok Vlkava u Kostomlat nad Labem. Od r. 2009 je sledována neobvyklá lokalita na rozhraní středních a severních Čech, kde korbikula dosahuje zatím největší známé koncentrace na našem území. Jde o betonový kanál vedoucí vodu z odkališť Elektrárny Mělník do Labe jižně od obce Horní Počaply. Byla měřena koncentrace korbikuly na této lokalitě na několika plochách o rozměrech 50 × 50 cm a v přepočtu na 1 m2 kolísala hustota v rozmezí 1 045–4 224 živých jedinců, tedy výrazně vyšší než na jiných místech České republiky a srovnatelná s nejvyššími hustotami tohoto mlže nalezenými v Evropě., The Asian Clam (Corbicula fluminea) is native to the south-eastern part of Asia and has been introduced to other continents including Europe. In the Czech Republic it was found in 1999 and is currently known from the Elbe River and lower parts of several tributaries (Ohře, Vltava). An unusual site with the occurrence of this invasive bivalve was found in 2009. A concrete canal conducting water from the sedimentation basin of the Mělník coal power station is inhabited by a large population. The density of its population was estimated to 1 045 – 4 224 living specimens/1 m2., and Luboš Beran.
Cistus salvifolius L. is the most widely spread Cistus species around the Mediterranean basin. It colonizes a wide range of habitats growing from sea level to 1,800 m a.s.l., on silicolous and calcicolous soils, in sun areas as well as in the understory of wooded areas. Nevertheless, this species has been mainly investigated in term of its responsiveness to drought. Our aim was to understand which leaf traits allow C. salvifolius to cope with low-light environments. We questioned if biochemical and physiological leaf trait variations in response to a reduced photosynthetic photon flux density were related to leaf morphological plasticity, expressed by variations of specific leaf area (SLA) and its anatomical components (leaf tissue density and thickness). C. salvifolius shrubs growing along the Latium coast (41°43'N,12°18'E, 14 m a.s.l., Italy) in the open and in the understory of a Pinus pinea forest, were selected and the relationships between anatomical, gas exchange, chlorophyll (Chl) fluorescence, and biochemical parameters with SLA and PPFD variations were tested. The obtained results suggested long-term acclimation of the selected shrubs to contrasting light environments. In high-light conditions, leaf nitrogen and Chl contents per leaf area unit, leaf thickness, and Chl a/b ratio increased, thus maximizing net photosynthesis, while in shade photosynthesis, it was downregulated by a significant reduction in the electron transport rate. Nevertheless, the increased pigment-protein complexes and the decreased Chl a/b in shade drove to an increased light-harvesting capacity (i.e. higher actual quantum efficiency of PSII). Moreover, the measured vitality index highlighted the photosynthetic acclimation of C. salvifolius to contrasting light environments. Overall, our results demonstrated the morphological, anatomical, and physiological acclimation of C. salvifolius to a reduced light environment., G. Puglielli, L. Varone, L. Gratani, R. Catoni., and Obsahuje bibliografii
Gloiopeltis furcata (Postels & Ruprecht) J. Agardh, a macroalga, which grows in an upper, intertidal zone, can withstand drastic environmental changes caused by the periodic tides. In this study, the photosynthetic and morphological characteristics of G. furcata were investigated. The photosynthetic performance and electron flows of the thalli showed significant variations in response to desiccation and salinity compared with the control group. Both PSII and PSI activities declined gradually when the thalli were under stress. However, the electron transport rate of PSI showed still a low value during severe conditions, while the rate of PSII approached zero. Furthermore, PSI activity of the treated thalli recovered faster than PSII after being submerged in seawater. Even though the linear electron flow was inhibited by DCMU [3-(3, 4-dichlorophenyl)-1,1-dimethylurea], the cyclic electron flow could still be restored. The rate of cyclic electron flow recovery declined with the increasing time of dark treatment, which suggested that stromal reductants from starch degradation played an important role in the donation of electrons to PSI. This study demonstrated that PSII was more sensitive than PSI to desiccation and salinity in G. furcata and that the cyclic electron flow around PSI played a significant physiological role. In addition, G. furcata had branches, which were hollow inside and contained considerable quantities of funoran. These might be the most important factors in allowing G. furcata to adapt to adverse intertidal environments., L. Huan, S. Gao, X. J. Xie, W. R. Tao, G. H. Pan, B. Y. Zhang, J. F. Niu, A. P. Lin, L. W. He, G. C. Wang., and Obsahuje bibliografii