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Invasive fish species in the Czech Republic
Lusk, Stanislav ; Lusková, Věra
In the Czech Republic, the following fish species are evaluated as invasive: Carassius auratus, a species showing a significantly negative influence on the occurrence of native species Carassius carassius and Tinca tinca in natural habitats. Certain manifestations and properties (such as the invasive way of dispersal, numerous populations, great ecological tolerance etc.) typical of invasive species can also be seen in Pseudorasbora parva, Ameiurus nebulosus, and Proterorhinus marmoratus. In some of its manifestations, even Cteropharyngodon idella can affect biodiversity in a negative way. One cannot exclude the future invasion or introduction of any alien species evaluated as invasive, particularly those of the genus Neogobius that occur in the Slovakian part of the Danube, and Perccottus glenii that has already invaded the Tisza River drainage area and the lower part of the Danube.
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Genus Cyprinus Linnaeus, 1758 - actual review on species diversity
Baruš, Vlastimil ; Peňáz, Milan ; Prokeš, Miroslav
In the genus carp (Cyprinus) is included currently 22 taxons in species levels and his fission into two subgenus: Cyprinus s. str. (with 17 species) and Mesocyprinus (with 5 species). Typical taxon on first subgenus Cyprinus (C.) carpio evaluate as a polytypical (with 4 subspecies). From 17 species of subgenus Cyprinus are 8 endemics only in Chinese province Yunnan (=Jünan), 1 species (C. qionghaiensis) province Sechwan, 1 species (C. acutidorsalis) on island Hainan, 5 species in northern as far as middle Vietnam and 1 species (C. intha) in Burma. Geographical distribution of 4 subspecies (C. carpio) is conformable with former views (Kirpichnikov 1967) and number of 2 - 3 domestication centres (Baruš et al. 2002). In subgenus Mesocyprinus registered species are Chinese faunistic elements with C. multitaeniata, that the was ascertained also in northern Vietnam.
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Usability of connectivity metrics as predictors of species distribution
Kučera, Michal ; Šímová, Petra (advisor) ; Krčílková, Šárka (referee)
The aim of this thesis is to evaluate whether connectivity indices are usable for bird prediction.
The study area contains of the whole country but is divided into separate squares with area of
133 km 2 each, where the presence or absence of the bird species is known. The dependence is
tested on landscape connectivity indices presented by prof. S. Saura. The land cover contains
of Corine land cover 2012 data. The results will be evaluated with logistic regression approach
on sample data including 4 different dispersal distances (500 m, 1 000 m, 2 000 m and 3 000
m) and 10 specific bird species typical for given land cover. The corelation between land cover
area presence of the bird is also tested.
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Seasonal dynamics of abundance and distribution of species and hybrids of the Daphnia longispina complex
Horová, Barbora ; Petrusek, Adam (advisor) ; Macháček, Jiří (referee)
I analysed seasonal changes in spatial heterogeneity of the taxonomic composition of the Daphnia longispina species complex in seven canyon-shaped reservoirs in the Czech Republic. The distribution patterns of species and interspecific hybrids along reservoir longitudinal axes differred between summer and autumn. In autumn, D. cucullata disappeared from upstream regions while D. longispina and D. galeata x longispina extended the shift from downstream regions to upstream. This temporal pattern may have been affected by decrease in fish predation pressure or deterioration of food conditions during the season. Powered by TCPDF (www.tcpdf.org)
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Mophological and molecular diversity of a tropical tree species Guazuma crinita in the Peruvian Amazon
Tuisima Coral, Lady Laura ; Lojka, Bohdan (advisor) ; Helena, Helena (referee)
Fast growing tree species Guazuma crinita (Malvaceae) was selected as a priority species for domestication in the Peruvian Amazon due its important contribution to the livelihood of local farmers. Its domestication process is still in an early age as for many tropical tree species little is known about its genetic variability and we dont know anything about the impact of domestication on its genetic resources. The main objective of this research was to assess the genetic variability of G. crinita within and among populations in the Peruvian Amazon by the use of morphological (wood physical traits) and molecular (ISSR and AFLP) markers.
Wood physical properties among six G. crinita provenances were evaluated. Wood samples were drilled from the base middle and top of the stem of 12 randomly selected eight-years-old trees for determination of wood measurement. Pearson correlations between physical properties were also determined. All wood physical properties except green density differed significantly among provenances. We also found statistically significant variation due to stem level position. The moderately dense wood and the coefficient of anisotropy (1.6) suggested that G. crinita has stable wood; they represent important advantages in terms of costs for transport and transformation process. The results suggested potential to select provenances with desirable wood properties for further breeding and domestication. Due to the variation found even in limited tree samples it is recommended further analysis with more extensive number of samples from different provenances and planting zones.
This research presents the first assessment of genetic variability based on inter-simple sequence repeat (ISSR) markers for 44 G. crinita genotypes from a clonal garden multiplication established in the Peruvian Amazon Research Institute (IIAP) in Ucayali region. Ten ISSR primers amplified a total of 65 bands of which 61 were polymorphic (93.8%). The range of DNA amplification varied from 260 to 2200 bp. Among the provenances overall genetic differentiation (Gst) was 0.03 indicating 97% of genetic diversity within provenances. Gene flow (Nm) was 12.9 alleles per generation. Cluster analysis was not related with geographic origin suggesting a common gene pool which was supported by calculation of weak positive correlation was found between genetic and geographic distance.
With the use of AFLP markers an insight on how domestication process does impact G. crinita genetic resources is also reported on this research work. I was able to generate fingerprint for 58 leaf samples representing eight provenances and three population types, 19 from a natural regenerated population 15 cultivated in home garden nursery and 24 from a collection of genotypes considered as semi-domesticated population. Seven selective AFLP primer combinations were used. A total of 171 fragments were amplified with 99.42% of polymorphism at species level. Each type of population generated fragments with 72.51% 49.12% and 54.39% of polymorphic fragments respectively. Neis genetic diversity and Shannon index information were found to be higher in the population of natural regeneration compared to overall semi-domesticated population (He = 0.10 and 0.9; I = 0.19 and 0.16 respectively). The analysis of molecular variation (AMOVA) showed higher variation within provenances rather than among (84% and 4% respectively). UPGMA clusters analysis and PCoA did not showed correspondence between genetic and geographic distance in addition their correlation was not significant. There was a significant genetic differentiation among types of population suggesting slight genetic bottleneck in semi-domesticated populations yet with relatively high levels of genetic variation.
In situ conservation for populations with high levels of genetic diversity was recommended. In addition proper management of natural regeneration and ex situ genotype collections might be a good conservation strategy to maintain G. crinita genetic resources.
The use of morphological (wood physical traits) and molecular markers were successful to reveal genetic variability of G. crinita and they could be used for other tropical tree species. For further researches it is emphasis to extent the number of samples and geographic scale.
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Impact of boric acid on Collembola, Protura and Pauropoda in a mountain elm forest in the Šumava National Park, Czech Republic
Rusek, Josef
A field experiment with weak boric acid (50g in 10 L water) was performed around trees of mountain elm (Ulmus glabra) in an Ulmeto-Aceretum forest community, Šumava National Park, to establish the impact of the acid on soil Collembola, Protura and Pauropoda. Boron should improve the physiological condition of the elms and their resistance to graphiosis. Soil samples (10 cm2 and 10cm deep) were taken around 10 trees on 15th July 1984. Eight of these trees (A-F, I, H) were without any previous treatment, whereas two trees (G, K) had received an application of boric acid eight months before. Immediately after the July sampling, boric acid was applied around five trees (A-E). Eight days later, a second sampling was done around trees A-E and control trees F and I. Five samples were taken around each tree at each sampling - 50 samples at the first sampling and 35 samples the second time. The soil fauna was extracted in a high-gradient apparatus, sorted into higher taxonomic groups and determined to species level in Collembola, Protura and Pauropoda. The community data and their differences before and after boric acid treatment were statistically evaluated using Sorensen's Average Linkage Method. The studied community was composed of 44 Collembola, 6 Protura and 2 Pauropoda species. The density of Collembola around the trees reached 8000-36 800 ind.m-2. The Shannon-Wiener index of diversity was high (H=3,077). Isotomiella minor, Protaphorura s-vontoernei and Parisotoma notabilis were the most dominant species. The first two species were euconstant and constant, while the third one (C=49,94) was almost euconstant. All other species were recedent or subrecedent. Twenty-one species of Collembola were present eight days after the treatment around trees A-E. Five recedent species occurred in lesser numbers after the treatment. Mesaphorura tenuisensillata became constant and P. notabilis recedent. The differences in collembolan density around individual trees before and after the treatment were not significant. Also, Sorensen's Average Linkage analysis did not show differences in this mesofauna community betweeen the treated and untreated trees.
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Testate amoebae (Protozoa) in soils of restored flowery meadows in the Bílé Karpaty Mts. (Czech Republic)
Balík, Vladimír
Soil testate amoebae assemblages were studied in the years 1999-2000 on six differently managed plots in the Bílé Karpaty Mts., South Moravia, Czech Republic. Four experimental plots with different plant cover established on the abandoned field and one conventionally cultivated field plot were investigated at the locality Výzkum. The plot with natural flowery meadow (control plot) was studied at the locality Čertoryje. 25 testate amoebae species were found in all five plots studied on the locality Výzkum. The testate amoebae assemblages were dominated by Cyclopyxis eurystoma var. parvula in 1999 and by Plagiopyxis declivis in 2000. The main coenological parameters increased rapidly during the observed years except for the cultivated field. On the control plot at the Čertoryje locality, 26 testate amoebae species were recorded. The testate amoebae assemblage on this plot was typical for the dry meadows of the warmer areas and was dominated by the Plagiopyxis declivis, Euglypha laevis and Trinema lineare. Values of the coenological parameters studied were typical for such type of habitat. Based on the obtained results, there was evident that the testate amoebae assemblages on experimental plots at the locality Výzkum developed very rapidly and their development tend to the composition characteristic for the old flowery meadows in the Bílé Karpaty Mts. No significant differences in the parameters of the testate amoebae assemblage were established among individual differently managed experimental plots, which situation probably reflects the short period of investigation.
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Poikilothermic traits in Mashona mole-rat (Fukomys darlingi). Reality or myth?
ZEMANOVÁ, Milada
The African mole-rats is a mammalian family well known for a variety of ecophysiological adaptations for strictly belowground life. The Mashona mole-rat (Fukomys darlingi) is supposed to have strong poikilothermic traits, because it is not able to maintain a stable body temperature at ambient temperatures below 20°C. In our study, we measured resting metabolic rate and body temperature of Mashona mole-rats across a gradient of ambient temperatures to test its poikilothermic traits. Tested mole-rats show typical mammalian pattern in resting metabolic rates. And their body temperature was stable at ambient temperatures from 10 to 25°C. We thus cannot confirm poikilothermic traits in this species.
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Occurrence of invasive species Eragrostis albensis in Prague and its surroundings
Mikulka, Jakub ; Holec, Josef (advisor) ; Jursík, Miroslav (referee)
Eragrostis albensis is an invasive weed. For invasive species it is typical that they are easily spread in to all manner of localities. Eragrostis albensis is recently described species, which spreads along the Elbe and the Vltava river. The purpose of this bachelor thesis was to find new places of occurrence in Prague and its surrounds and especially around the Vltava river. There were found a few locations where the occurrence of Eragrostis albensis was confirmed and these areas were always ruderal. At most of the areas there were maximum 3 plants. Only in one locality there were over 70 plants of Eragrostis albensis (locality Dvořákovo nábřeží). This invasive weed has wide ecological amplitude, it occurs especially on embankment nearby river, but it can also grow on pavements affected by dry. This species well tolerate disturbed areas and floods can help this weed to create new suitable locations. According to this monitoring it´s obvious, that Eragrostis albensis is a part of some ruderal districts in Prague.
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