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Marcin Becher, Dorota Kalembasa, Krzysztof Pakuła and Elżbieta Malinowska

Abstract

Pedological studies were carried out in the upper course of the Liviec River involving laboratory analyses of three profiles of hemic muck organic soil. The objective was to evaluate the basic properties (pH, crude ash content and carbon and nitrogen content) and to determine the speciation of carbon and nitrogen based on the sequential extraction with a neutral reagent (0.25M KCl) and two-stage acid hydrolysis at different concentrations of hydrogen ions (0.25M H2SO4 and 2.5M H2SO4).

The muck horizons, in relation to the peat horizons, had a higher content of ash and a lower concentration of carbon and lower carbontonitrogen ratios. The reduction of acidity in the examined soil had a significant impact on a higher proportion of mineral nitrogen forms. The moorshing process caused by desiccation of the examined soil contributed to an increase in the proportion of soluble organic matter forms (extracted with 0.25M KCl) and easily hydrolysing organic forms (extracted with hydrolysis in 0.25M H2SO4).

Open access

Manuel Ortiz and Ignacio Winfield

Abstract

The description of a new species of amphipod crustacean (Gammaridea) of the genus Leucothoe found in a sponge, collected during the 3rd Joint Cuban-Spanish Expedition to the waters of Guanahacabibes Peninsula, at the Western Cuban Platform, in July 2008, is given. The main differences among L. luquei n. sp., and the other species known in the region, are also presented.

Open access

Adrian Mestecăneanu and Florin Mestecăneanu

Observations regarding the flight biology and behaviour of the Common buzzard (Buteo Buteo) in the Râul Doamnei hydrographical basin (Romania)

In this paper, the authors analyse the flight biology and behaviour of the Common buzzard (Buteo buteo) observed in the Râul Doamnei hydrographical basin, depending on the environmental conditions and ecological seasons. Along three years, during the 3031 observations, 4549 individuals were observed.

Open access

Norma Rentería, Ramón Silva-Vázquez, Guadalupe Morrillón, Cristóbal Aguilar and Raúl Herrera

Genetic Diversity of Mexican Oregano Lippia berlandieri Schauer, from the Chihuahuan Desert Area

The Mexican oregano Lippia berlandieri Schauer is widespread in Mexico. Several studies have involved the characterization of its essential oil in order to use it as food additive and for medical aims, as well as its antimicrobial and antioxidant capacity, although there is a lack of information about genetic diversity of this species. In order to increase Lippia berlandieri Schauer application, knowledge of the genetic characteristics of the species and creation of a program for germplasm conservation seem to be essential. This study was carrying out in order to understand the population genetics of Lippia berlandieri Schauer. Oregano seeds were collected from 8 locations of the Chihuahua Southeastern desert area. The results showed high genetic variability among oregano populations suggesting that this species is mainly allogamous, pollinated mainly by insects because of the attractive flower color; AMOVA showed genetic differences within and among populations, the last one was found approximately 5 times higher than the genetic differences within populations. The analysis of the Wright's statistics, especifically FIS, supported the hypothesis that plants are not self-pollinating. On the other hand, it was found that the number of plants per a sample recommended for further genetic analysis of this specie is 13 or more.

Open access

Katarína Holcová

Abstract

The reactions of foraminiferal and calcareous nannoplankton assemblages to global warming and cooling events in the time intervals of ca. 27 to 19 Ma and 13.5 to 15 Ma (Oligocene and Miocene) were studied in subtropical epicontinental seas influenced by local tectonic and palaeogeographic events (the Central Paratethys). Regardless of these local events, global climatic processes significantly influenced the palaeoenvironment within the marine basin. Warm intervals are characterized by a stable, humid climate and a high-nutrient regime, due primarily to increased continental input of phytodetritus and also locally due to seasonal upwelling. Coarse clastics deposited in a hyposaline environment characterize the marginal part of the basin. Aridification events causing decreased riverine input and consequent nutrient decreases, characterized cold intervals. Apparent seasonality, as well as catastrophic climatic events, induced stress conditions and the expansion of opportunistic taxa. Carbonate production and hypersaline facies characterize the marginal part of the basins. Hypersaline surface water triggered downwelling circulation and mixing of water masses. Decreased abundance or extinction of K-specialists during each cold interval accelerated their speciation in the subsequent warm interval. Local tectonic events led to discordances between local and global sea-level changes (tectonically triggered uplift or subsidence) or to local salt formation (in the rain shadows of newly-created mountains).

Open access

Matt von Konrat, Peter de Lange, Juan Larraín, Jörn Hentschel, Benjamin Carter, Jon Shaw and Blanka Shaw

Abstract

Frullania is a large and taxonomically complex genus. Here a new Frullania, F. toropuku von Konrat, de Lange & Larraín, sp. nov. is described from New Zealand. Frullania toropuku is placed in F. subg. Microfrullania. The new species is readily recognised by a combination of morphological characters associated with branching, the perianth, sexuality, and sporophyte, which distinguish it from all other New Zealand and regional species of Frullania. However, morphologically F. toropuku most closely resembles the widespread F. rostrata, which might well be regarded as a Southern Hemisphere equivalent of the Holarctic F. tamarisci species-complex in terms of its cryptic diversity. A combination of morphological characters associated with branching, the perianth, sexuality, and sporophyte distinguish F. toropuku from all other New Zealand and regional species of Frullania. A comparison is made between F. toropuku and morphologically allied species of botanical regions outside the New Zealand region and an artificial key is provided. In a prior investigation, maximum parsimony and maximum likelihood analyses of nuclear ribosomal ITS2 and plastidic trnL-trnF sequences from purported related species confirms its independent taxonomic status and corroborates its placement within F. subg. Microfrullania. The ongoing studies of Frullania species-complexes reveal the urgent need for more species-level phylogenies with extensive population sampling to approximate the actual diversity of Frullania, and to elucidate speciation processes and distribution range formation.

Open access

Agnieszka Jeske and Barbara Gworek

the Total Environment   312 : 195-219. KABATA-PENDIAS A., PENDIAS H. 1993. Biogeochemia pierwiastków śladowych Wyd. Nauk, PWN, Warszawa: 225-227. OSTROWSKA A., GAWLIŃSKI S., SZCZUBIAŁKA Z. 1991. Metody analizy i oceny właściwości gleb i roślin. Instytut Ochrony Środowiska: 47-48. ÓVÁRI M., CSUKÁS M., ZÁRAY Gy. 2001. Speciation of beryllium, nickel, and vanadium in soil samples from Csepel Island, Hungary. Fresenius J. Anal. Chem.   370 : 768-775. PANICHEV N

Open access

Piotr Z. Białooki, Christoph Germann and Jean Pelletier

-228. MAGNANO L. 1998. Notes on the Otiorhynchus GERMAR, 1824 complex (Coleoptera: Curculionidae). [in:] E. COLONNELLI, S. LOUW, G. OSELLA (eds.). Taxonomy, ecology and distribution of Curculionoidea (Coleoptera: Polyphaga). Proceedings of a Symposium (22 August, 1996, Florence, Italy). XX International Congress of Entomology. Museo Regionale di Storia Naturale, Torino, 51-80. MAGNANO L. 2003. Un nuovo genere e una nuova specie di Cipro [sic!] appartenenti alla tribu Otiorhynchini (Coleoptera: Curculionidae). Snudebiller 4: 228-230. MAGNANO L

Open access

Erika Schneider-Binder

Abstract

The European species of the genus Marsilea are presented, with special regard to Four leaf water clover Marsilea quadrifolia L., the single species occurring in Central Europe. Based on field research on the Upper Rhine in Germany and the Lower Danube in Romania the ecological requirements of the species and the plant communities in which the species lives are analysed and compared with data from other European countries. Due to the decline of the species populations as a consequence of human activities, all European Marsilea species are rare, vulnerable, endangered by extinction or extinct in the wild and included in the Red data books of most European countries. Also all the European water clovers Marsilea strigosa, Marsilea batardae and Marsilea quadrifolia have been included in the Appendix I of the Bern Convention (1979) as strictly protected species and in the Annexe II of the European Flora Fauna Habitat Directive 92/43/1992. After analysis of ecological conditions, the state of conservation and the Red List categories of Marsilea quadrifolia following IUCN criteria in the countries of occurrence are presented and possible measures for conservation are discussed as well as realised reintroduction of the species in the wild

Open access

Mohamed Menioui

Abstract

A new apseudomorph tanaidacean species, Calozodion moyas sp. nov., from the Moroccan Atlantic waters is described. The new species is the third species of the genus Calozodion Gardiner, 1973 known in the western African coasts and the tenth in the worldwide fauna. The main features by which the new species differs from all others of the genus Calozodion consist in the presence of a mediodorsale process at the basis of pereopod 2 (absent in C. bacescui Guţu, 1996, C. dollfusi Guţu, 1989, C. heardi Guţu, 2002, C. multispinosum Guţu, 1984 and C. singularis Guţu, 2002) and of five long setae on the first article of mandible palp (comparatively to at most three setae in the species C. dominiki Bochert, 2012, C. simile Guţu, 2006, C. suluk Bamber & Sheader, 2005 and C. wadei Gardiner, 1973). Other differences result from the identification key of the species of the genus Calozodion presented in the final part of this paper.