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1.
2.
The profundal community of L’adové pleso (an oligotrophic high mountain seepage lake at an altitude of 2,057 m with a max. depth of 18 m and an ice-cover period from October–July) was studied from December 2000–October 2001. Chironomidae, the most significant part of the studied community, are represented by four taxa and dominated by Micropsectra radialis Goetghebuer, 1939 and Pseudodiamesa nivosa (Goethgebuer, 1928). These two species showed a 1-year life cycle. The total densities of chironomids varied from 0 to 5,927 ind. m?2; no chironomids, or very low densities, were found during the winter/spring period, probably due to low oxygen concentrations in the medial part of the lake. These low oxygen concentrations probably caused the relocation of larvae from the medial part of the sedimentary area at the same time.  相似文献   

3.
Stratigraphy of cladoceran remains in the upper 18 cm of a sediment core from the Lake Černé was studied. The successive disappearance of Bosmina longispina, Daphnia longispina and Ceriodaphnia quadrangula from the upper layers of the sediment corresponds with our knowledge concerning the disappearance of these species from the open water.  相似文献   

4.
Deviations between observed and simulated discharge in the basins along the borders of the Czech Republic with Austria and Germany provide outputs which enable to follow changes in runoff. The three basins range in area from 100 to 200 km2 and the experimental basin Liz with an area of 0.99 km2. The selected experimental catchments are situated in or close to the National Park of the ?umava Mts. This region is described also in Tesa? et al. (2006). Results indicate that changes in runoff appear to be related to damages in forest cover caused by wind disasters and insects damages.Daily time series used for simulations are approximately 40 years long and 20 years in the experimental basin. Two different models of the rainfall — runoff process have been used for simulations and the outputs provide comparable results. The models are the conceptual model Sacramento (Burnash, 1995) and the model BROOK’90 (Federer, 1993). The second model distinguishes the details concerning evapotranspiration, including transpiration, rain and snow interception and snow and soil evaporation.The indicated runoff changes seem to be rather complex. After deforestation the volume of runoff generally increases and peak flows of floods are higher, but low flow in rainless periods show complicated courses.  相似文献   

5.
Lepidopteran assemblages in Temnosmrečinská dolina valley (High Tatra Mts, Western Carpathians, Slovakia) were investigated. Recent data about the occurrence of lepidopteran species are compared with those which were obtained 55 years ago. Lepidoptera were monitored at seven sites comprising the subalpine to alpine zone of the valley. Fifteen of the originally recorded species were not found, however, the occurrence of six new species was recorded. In total, 61 summer lepidopteran species are known from the Temnosmrečinská dolina valley. The comparison of the recent lepidopteran assemblages shows a decline in species richness, abundance and frequency at individual monitoring sites. It seems that the changes are caused by plant community succession in the valley — overgrowth of dwarf pine, transformation of meadow communities to Calamagrostigetum and overgrowth of peat-bogs, resulting in loss of food resources for adult Lepidoptera.  相似文献   

6.
Four species of the genus, Bryoria were found in the Sučí Potok Valley: B. capilaris (Ach.) Brodo & D. Hawksw., B. fuscescens (Gyeln.) Brodo & D. Hawksw., B. implexa (Hoffm.) Brodo & D. Hawksw., B. nadvornikiana (Gyeln.) Brodo & D. Hawksw. The most common species in the valley was B. implexa. Four chemotypes of this lichen were recognized.  相似文献   

7.
A one-year study of the phytoplankton of remote mountain lake L’adové pleso (2057 m. a.s.l.), situated in the High Tatra Mountains, was carried out in 2000–2001. Seasonal development of the species structure and depth distribution of biomass, as well as chlorophyll-a concentrations, and chemical characteristics of the lake water were examined. The phytoplankton was made up of a low number of nanoplanktonic unicellular species, mainly flagellates from Cryptophyceae and Chrysophyceae. Plagioselmis lacustris, Cryptomonas cf. erosa and Ochromonas spp. were the most important with regards to both abundance and biomass. The phytoplankton showed a marked seasonal development. During most of the ice-covered period, abundances of phytoplankton remained very low. In regard to the vertical distribution, both species composition and total biomass were clearly stratified during most sampling dates. The amount of chlorophyll-a per unit biovolume varied considerably, and significantly higher values were found on sampling dates with complete or partial ice cover. Our data on pH and phytoplankton were compared with a previous study in 1990–1991 in order to evaluate possible changes associated with the decrease of acid deposition. The extent of episodic acidification of the lake water has diminished both in time and space, and lake water pH has slightly increased. We observed a shift in species composition, and an important increase of total phytoplankton abundance. This could be considered as a first sign of biological response to changing chemical conditions.  相似文献   

8.
Abstract

The distribution of inorganic and organic lead species in atmospheric and surface waters from the ?ibenik area (central part of the Eastern Adriatic coast) was investigated. The concentration range of lead compounds in rainwater was 12,000 to 57,000 ng Pb L?1 for total lead, and 10 to 96 ng Pb L?1 for ionic alkyllead compounds (mostly in the form of trialkyl derivatives). In seawater, trialkyllead compounds were detected in concentration from <0.5 to 12.5 ng Pb?1 L, which represented 0.5 to 6.8% of the total lead. These results were compared with data obtained elsewhere, and the influence of lead compounds emitted from leaded gasoline (from automobiles and gasoline stations) on the adjacent water body is elucidated.  相似文献   

9.
Spatial distribution of ground beetles and moths in the isolated Central European Mrtvy luh bog was analyzed. The most stenotopic tyrphobiontic species (relicts restricted to the peat bog) of ground beetles (Coleoptera: Carabidae) and moths (Lepidoptera) are distributed according to a distinct ecological gradient between the bog margin (lagg) and the bog centre. The degree of habitat preference between the bog margin and centre is taxonomically specific and significant. A list of stenotopic species of high conservation value is given. Several tyrphobiontic species occur in the treeless bog centre only. The tyrphophilous and tyrphoneutral species are distributed in the peat bog mostly randomly, some of such species prefer bog margins. The migratory highly opportunistic moths from habitats outside the bog usually cross the treeless centre. Most of the ubiquitous tyrphoneutral and migratory moths represent the faunal component, which is a very temporary phenomenon only, not associated with the peat bog permanently. The conservation of insect biodiversity associated with isolated peat bogs depends on complete preservation of the edaphic ecological conditions of the fragile paleorefugial habitat island and its spatial structure.  相似文献   

10.
The physical and chemical variabilities as well as the distribution of diatoms of six boreal lakes in the Laurentian Mountains (southern Québec, Canada) were studied. The lakes are located along an altitudinal gradient and were sampled at a biweekly resolution from May through October, 2002. In general, we found later onset and weaker lake stratification under colder climates. Lake circulation and SiO2 are strongly correlated and together significantly explain the distribution of diatoms of the individual lakes. Diatoms that accumulated in the sediment traps were mostly composed of benthic species, suggesting resuspension. However, diatom flux and lake circulation were not significantly correlated, the diatom assemblages in the sediment traps were similar in two consecutive years, and species–environment relationships were comparable among lakes, which indicates that the effects of resuspension were minimal. In addition, we found that one lake was more productive due to forest logging. The forest in the catchment of Lake Maxi was entirely clear-cut shortly prior to our sampling. Mean total phosphorus, dissolved organic carbon, and chlorophyll a concentrations were significantly higher when compared to the other five study lakes. This study seeks to improve our understanding of how diatoms in boreal lakes respond to climate change and forest clear-cut.  相似文献   

11.
The species composition of the family Anthomyiidae in six peat-bogs in the Šumava Mts is analysed with regards to dominance, constancy, seasonal occurrence and type of distribution of each species. Anthomyiid communities in all sites are compared based on the number of species, species richness, diversity and equitability indices, as well as coefficients of similarity and Principal Components Analysis (PCA). Three collecting methods are compared: yellow pan water traps (439 specimens/43 species), sweeping (93/18) and Malaise traps (97/22). Three species, Pegoplata aestiva (24.17%), Delia platura (14.47%), and Hylemya nigrimana (11.29%) were eudominant, two further species were dominant: Delia cardui (8.74%) and Botanophila fugax (8.27%). Two species, Botanophilia fugax and Delia platura, were found in all study sites. These species, together with those collected in five sites (Delia cardui, Heterostylodes nominabilis and Hylemya vagans), had a constancy rate higher than 75% and belonged to the category of euconstant species.  相似文献   

12.
Six pollen diagrams from peat bogs in the Vltavsky luh (upper Vltava river valley) provide new information about vegetation reconstruction, woodland dynamics, and local development of mires during the Late-glacial and Holocene. Vegetation development began in the Oldest Dryas/B?ling with open park plant cover. In the Aller?d, woodland with Pinus and Betula developed, and in the Younger Dryas there was a steppe tundra with plants of open habitats. In the Pre-boreal, woodland tundra grew. In the Boreal, Corylus spread, and a major expansion of Picea began in the early Boreal. Picea spread during the Atlantic probably by two different migration routes. Fagus immigrated earlier than in the Bayerischer Wald and Oberpf?lzer Wald in the adjoining parts of Germany, and had its major expansion in the early Atlantic. Abies expanded in the late Atlantic. The great abundance of Abies in this area is remarkable, forming Abies or Abies-Fagus woods in less extreme habitats. Human occupation started in the Sub-boreal, as shown by both archaeology and palynology. However, human impact is recognized from anthropogenic indicators which appear in the early Atlantic. At the end of the later Sub-atlantic the development of natural woodland was interrupted by plantation of Picea according to historical and palynological evidence. Received November 13, 2000 / Accepted July 7, 2001  相似文献   

13.
14.
Cover of higher plants (in 4 × 4 m plots), groundwater table height, and water chemistry in boreholes were sampled at 43 sites along three cross-sectional transects in a flat floodplain of the Upper Vltava River in the Šumava Mountains (Šumava National Park, Czech Republic). The goal was to describe the relationships between vegetation and alluvial environment. Correlations between hydrochemical and plant community characteristics were calculated, and Canonical Correspondence Analysis (CCA) was used to express relationships between the abiotic factors and vegetation. The following characteristics were significantly correlated with the vegetation pattern: mean height of the water table, distance from the river, pH, and concentration of NH4 and humic acids in the groundwater. Two distinct zones were distinguished in the floodplain: Zone I was under direct influence of the river, and exhibited higher pH and ammonium content in a fluctuating groundwater table. Zone II, covering more than half of the floodplain extent, was under the prevailing influence of water coming from the adjacent upland, and exhibited lower pH, higher content of humic acids, and a higher and relatively stable groundwater table. A diverse mosaic of the riparian communities, especially of tall-sedge and tall-grass marshes and alluvial meadows, was typical for the former zone, while peatland vegetation characterised the latter one. The floodplain exhibited a rather oligo- to mesotrophic status with only very local eutrophication, and harboured diverse and valuable plant communities. The protection of this floodplain should be among the priorities of the National Park authorities.  相似文献   

15.
Kiss  O.  Schmera  D.  Fehér  I. 《Hydrobiologia》2003,506(1-3):365-372

Seventeen caddisfly species of four families (Limnephilidae, Sericostomatidae, Phryganeidae, and Leptoceridae) with a total of 1047 individuals were collected from four sampling sites in the littoral zone of Disznóskút Lakes in the Bükk Mountains. Three of these four families of Trichoptera were also recorded in the Central European lakes. From among the four substrates (sand, silt, large stones, and aquatic plants) of the littoral zone, silt and aquatic plants were dominant. Besides species of Limnephilidae found in higher than the average abundance in the silt, species of Phryganeidae and Leptoceridae also occurred. The trophic relationships of the species of these families can be considered as follows: shredders- predators- scrapers, shredders- detritivores- predators, and predators- shredders- scrapers. From the aquatic plants the species of Limnephilidae, Phryganeidae and Leptoceridae, belonging to the trophic relationships of detritivores- shredders, scrapers- predators, shredders- detritivores- predators, and predators- shredders- scrapers- detritivores were collected. The analysis (PCA) of the spatial and seasonal distribution of Trichopteran larvae at the four littoral zone sites shows that the assemblages collected near the inflow of the stream into the lake in late summer and near the inflow of the small channel into the lake in summer are very different from the others, for which Limnephilus elegans, Micropterna lateralis, and Stenophylax permistus are responsible at the previous site, while Halesus digitatus, Halesus tessellatus, and Mystacides nigra are responsible at the latter one. The other assemblages (mostly those in winter) are very similar to each other, which can be explained by the decreasing number of detectable species and their presence in low abundance. For the variance, Limnephilus rhombicus (57%) and Potamophylax nigricornis (16%) are essentially responsible. Considering the species composition of the larval assemblages, the site at the inflow of the stream into the lake was the most different (38%) from the others, and was 62% similar to them. This dissimilarity can possibly be explained by the presence of a mixed assemblage with typical stream and lake inhabitants of species of Limnephilidae present in high abundance at this silt dominated site and other caddis species that are typical stream inhabitants or common in streams and small rivers, and may have drifted into the lake.

  相似文献   

16.
We combine information about the evolutionary history and distributional patterns of the genus Saintpaulia H. Wendl. (Gesneriaceae; ‘African violets’) to elucidate the factors and processes behind the accumulation of species in tropical montane areas of high biodiversity concentration. We find that high levels of biodiversity in the Eastern Arc Mountains are the result of pre-Quaternary speciation processes and environmental stability. Our results support the hypothesis that climatically stable mountaintops may have acted as climatic refugia for lowland lineages during the Pleistocene by preventing extinctions. In addition, we found evidence for the existence of lowland micro-refugia during the Pleistocene, which may explain the high species diversity of East African coastal forests. We discuss the conservation implications of the results in the context of future climate change.  相似文献   

17.
All species of Daphnia (Cladocera) produce, at some stage in their life cycle, diapausing eggs, which can remain viable for decades or centuries forming a “seed bank” in lake sediments. Because of their often good preservation in lake sediment, they are useful in paleolimnology and microevolutionary studies. The focus of this study was the analysis of cladoceran resting eggs stored in the sediment in order to examine the ephippial eggs bank of Daphnia pulicaria Forbes in six mountain lakes in the High Tatra Mountains, the Western Carpathians (northern Slovakia and southern Poland). Firstly, we analyzed distribution, abundance and physical condition of resting eggs in the sediment for their later used in historical reconstruction of Daphnia populations by genetic methods. To assess changes in the genetic composition of the population through time, we used two microsatellite markers. Although DNA from resting eggs preserved in the High Tatra Mountain lake sediments was extracted by various protocols modified for small amounts of ancient DNA, DNA from eggs was not of sufficient quality for microsatellite analyses. Distribution curves of resting eggs from sediment cores correspond to the environmental changes that have occurred in the High Tatra Mountains area during last two centuries (atmospheric acid deposition, fish introduction) and demonstrate their influence on natural populations. Evaluation of ephippia physical condition (the most common category was empty ephippial covers) suggests that the majority of resting eggs hatched to produce a new generation of Daphnia or may be due to failed deposition of resting eggs by Daphnia to the chitinous case. In conclusion, age, low quantity and poor physical condition of resting eggs from these Tatra lake sediments proved to be unsuitable not just for use in genetic analyses, but also the possibilities of autogenous restoration of Daphnia populations from the resting egg banks in the Tatra sediments are negligible.  相似文献   

18.
Renata Jach 《Facies》2005,50(3-4):561-572
The Lower-Middle Jurassic of the Krína unit in the Western Tatra Mts. (southern Poland) shows considerable facies variation. Crinoidal grainstones of variable thickness (up to 12 m) are one of characteristic facies. They occur above spiculites which were deposited below storm wave base on the slopes of elevated horsts. First single beds of crinoidal limestones occur within spiculites. They were deposited as event beds, generated probably by storms. The overlying thick complex of well-sorted grainstones composed almost entirely of crinoidal ossicles display widespread erosional bed amalgamation, hummocks and locally wave-formed ripples. The above characteristics are the effects of multiple reworking and winnowing of fine crinoidal material by oscillatory currents related to storms. This proves that the sedimentation of the crinoidal grainstones took place between the storm and the fair-weather wave bases. The vertical transition from spiculites with intercalations of crinoidal limestone beds towards the crinoidal grainstones is interpreted as the result of a shallowing upward trend. Since this trend is opposite to the global Early Toarcian transgression, this could be related to an uplift due to local block tectonic activity. The evidence for that is diversification of facies in the Krína Basin, as well as submarine slumps recorded in spiculites. The location of Krína Basin on relatively low northern latitude and on western edges of great Tethys Ocean during Early Jurassic enabled the formation of the crinoidal tempestites.  相似文献   

19.
Attitudes towards protected areas are seen as a key factor in influencing their success. While the majority of park–people relation research has addressed local residents’ attitudes towards protected areas in their own country, analyses on their attitudes towards a neighbouring national park on the other side of the border have rarely been carried out. This study investigated the attitudes of local residents in Upper Austria towards the Czech ?umava National Park. In 2008, residents (N = 468) of four rural communities bordering the ?umava National Park answered a mailed questionnaire. Compared to national parks in general, the ?umava National Park was perceived as not providing as many ecological, social, and economic benefits as others. Psychological reactance, past visits to the ?umava National Park, and attitudes towards landscape change and national parks in general predicted attitudes towards the ?umava National Park, while group membership, except for that of being a farmer, was not significant. Variables that have been previously identified as influencing the attitudes of local residents towards protected areas also seem to be relevant for protected areas on the other side of the border, while items addressing local trans-border issues and group membership appear to be less important. Management implications are discussed.  相似文献   

20.
The original version of the article was published in Biologia 68 (6): 1198–1210 (2013), DOI: 10.2478/s11756-013-0268-1. Unfortunately, the original version of this article contains a mistake in Acknowledgements on page 1209. Here we display the corrected version of the Acknowledgements.  相似文献   

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