Aerosolové částice se vyskytují všude okolo nás v mnoha různých formách, například jako prach, mlha, kouř, dým nebo smog. Tyto částice ovlivňují dohlednost, klima, zdraví obyvatel a jejich kvalitu žvota. Atmosférický aerosol je v současné době jedním z největších problémů znečištění ovzduší. Tento článek dokumentuje vznik aerosolu, formy jeho výskytu a depozice. Dále popisujeme nejužívanější metody jeho odběru a monitorování. V závěrečné části jsou ukázány první výsledky získané pomocí nového zařízení na zkoumání resuspenze aerosolu - resuspenzní komory., Martin Civiš, Jan Hovorka, Devraj Thimmaiah., and Obsahuje bibliografii
The biological soil crusts (BSCs) in the NW Negev cause local water redistribution by increasing surface runoff. The effects of pore clogging and swelling of organic and inorganic crust components were intensively investigated in earlier studies. However, the effect of water repellency (WR) was not addressed systematically yet. This study investigates subcritical WR of BSCs in three different study sites in the NW Negev. For this purpose, three common methods to determine soil WR were used: (i) the repellency index (RI) method (ii) the water drop penetration time (WDPT) test and (iii) the Wilhelmy plate method (WPM). Furthermore, the potential influence of WR on local water redistribution is discussed and the applied methods are compared. We found the BSC to be subcritically water repellent. The degree of WR may only affect water redistribution on a microscale and has little influence on the ecosystem as a whole. The RI method was clearly the most appropriate to use, whereas the WDPT and the WPM failed to detect subcritical WR.
Seeds of many species of plants may survive for a long time in the soil and germinate when brought to the surface, but
whether they are subsequently eaten by seed predators is unknown. We examined the preferences of three species of carabids
(Coleoptera: Carabidae) for 25 species of seeds and determined the difference in palatability between freshly dispersed and those
buried for six years. The stability of their preferences was tested using a collection of seeds of different species, each of which was
offered fresh or after being buried. Carabid beetles readily accepted previously buried seeds as food. In total, Pseudoophonus
rufi pes and Amara littorea ate more fresh seeds than previously buried seeds, while the opposite was true for Harpalus affi nis. The
seeds of some species were even more attractive to carabids after burial than in the fresh state. For all the species of carabids
tested, the diet breadth was similar when the beetles were fed fresh or buried seeds, but the preferences for fresh and buried seed
of particular species were correlated only in P. rufi pes and A. littorea. We measured the seed characteristics (mass and viability)
likely to be associated with the loss of attractiveness to carabids during burial. The change in carabid consumption was not related
to changes in any of these characteristics. This fi nding indicates that factors responsible for variation in seed acceptability are
complex. This study provides the fi rst conclusive evidence that invertebrate seed predators will feed on seeds from seed banks,
although they prefer fresh seeds.
Discussion Section
The contributions reply to several theses contained in Blanka Soukupová´s study and reactions of the research fellows from the Institute of European Ethnology (both contributions were published in the previous issue of the Ethnographical Journal), First, Blanka Soukupová responds to some impulses of the research fellows from the Brno university institution, she refers to Antonín Václavík´s activities during the period of the First Czechoslovak Republic and Protectorate of Bohemia and Moravia. Karel Altman´s text (Antonín Václavík - kolaborant? (K rozvoji českého národopisu v době tzv. protektorátu a jeho poválečným důsledkům [Antonín Václavík - a Collaborationist? (On the Development of Czech Ethnology in the Period of the So-Called Protectorate and its Post-War Consequences)]) is based on the analysis of ethnological and historical literature and the study of archival sources. Based on the collected information, the text tries to disprove Blanka Soukupová´s pronouncement about Antonín Václavík´s collaborationism in the first half of the 1940s. The closing contribution by Josef Jančář called Evropská etnologie a český národopis [The European Ethnology and Czech Ethnography] sets the use of the word “ethnography” into the period context of the first half of the 20th century. Using the example of the ethnographic area of Slovácko, it also explains how dangerous it is to simplify some historical facts. Although several groups of collaborationists actively used the symbolism of national costumes or relation to the region or Moravia, they are only one of the wide range of activities (in contrary, many of them featured resistance nature) developed by the inhabitants of the region during the period of the Protectorate of Bohemia and Moravia. and K tomuto článku je připojeno závěrečné shrnutí a klíčová slova k předchozí polemice o Antonínu Václavíkovi
Two new species of two genera of the order Diphyllidea van Beneden in Carus, 1863, Halysioncum Caira, Marques, Jensen, Kuchta et Ivanov, 2013 and Echinobothrium van Beneden, 1849 sensu stricto are described from Aetomylaeus cf. nichofii (Bloch et Schneider) off the Iranian coast of the Persian Gulf. Halysioncum kishiense sp. n. differs from all other congeners in the number of apical hooks with the exception of H. hoffmanorum (Tyler, 2001) and H. pigmentatum (Ostrowski de Núñez, 1971). Halysioncum kishiense sp. n. can be easily differentiated from H. hoffmanorum and H. pigmentatum by the number of hooklets and testis numbers. Echinobothrium parsadrayaiense sp. n. is differentiated from all its congeners except for E. acanthinophyllum Rees, 1961 by its hook formula. The number of spines per column on the cephalic peduncle, the number of testes and possession of a thick-walled rather than thin-walled vagina distinguish E. parsadrayaiense sp. n. from E. acanthinophyllum. To date, with these two new species, five species of Diphyllidea have been reported from the Persian Gulf.
The Surface Water Department of the Czech Hydrometeorological Institute in 2006 selected a new period for the evaluation of hydrological characteristics of mean daily discharge series. Initially, two fortyyear long periods were considered: 1961-2000 and 1966-2005 and the period of 1961-2005 was finally accepted. Comparison of the still used 1931-1980 period with the new one was carried out using the data from 50 Czech gauging stations that had continuous data time series. The mean long-term runoff of Czech rivers changed very little from 1931-1980 to 1961-2005. Comparison of the variation coefficients brought similar results. However, among specific M-day discharges the low flow values (e.g. Q355d) showed a significant increase. This might reflect not only natural causes but could suggest anthropogenic factors as well. Trend analyses started with testing mean annual runoff at 65 Czech gauging stations that were not influenced by human activity. 34 stations showed an increasing trend and 31 a decreasing trend. However, the trend was statistically significant only at one station. Trends of individual months dramatically differentiate. In January through March the increasing trends prevail. March trends show the highest number of stations with a significant increase. The three following months are complete opposites in which decreasing trends dominate. In May and June, not a single increase was recorded and many decreases were statistically significant. Almost no significant trends were examined in the months of the second half of the year. and V posledních měsících se oddělení povrchových vod ČHMÚ zabývalo výběrem období pro výpočet nových hydrologických charakteristik M-denních průtoků na českých tocích. Uvažována byla čtyřicetiletí 1961-2000 a 1966-2005, nakonec však bylo přijato období 1961-2005. Na datech z 50 vodoměrných stanic, které měly nepřerušené řady pozorování, bylo uskutečněno první srovnání statistických charakteristik období 1931-1980 (doposud používané) a 1961-2005. U nového období byly u neovlivněných stanic vyhodnoceny trendy průměrných ročních průtoků a průtoků jednotlivých měsíců.
The erythrinid fish Hoplias malabaricus in Paraguay harbour two species of proteocephalid cestodes, Proteocephalus regoi sp. n. and Nomimoscolex matogrossensis Rego et Pavanelli, 1990. The former species differs from most South American members of Proteocephalus from fishes by: 1) presence of a small apical organ, 2) distribution of vitellaria, which do not reach to posterior margin of segment and 3) posterior position of vagina. Nomimoscolex matogrossensis is redescribed on the basis of type and recent material, with emphasis given to the morphology of genital organs and scolex, which possesses an apical organ. Both species possess a dense network of osmoregulatory canals in the postacetabular region of both scolex and neck. Proteocephalus regoi sp. n. is the first representative of the subfamily Proteocephalinae parasitizing erythrinid fish.