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1.
Capsule?Of 26 species of wintering waterbirds, 18 showed an increase in numbers, five showed a decrease and two showed no change.

Aim?To assess long-term trends in the numbers and distribution of the 26 most abundant wintering waterbird species in the Czech Republic.

Methods?We used International Waterbird Census data from between 48 and 639 wetland sites which had been counted annually in the Czech Republic from 1966 to 2008. From these data long-term changes in numbers and distributions were determined. Log-linear Poisson regression analysis was used to estimate missing data using trim software. The distribution of each species was described as the ratio of the number of sites occupied by that species to the total number of sites investigated.

Results?Increasing trends were found for 18 species, five species were found to be declining, one species was stable and two species were found with uncertain trends. Wintering distributions (the ratio of sites occupied by a given species to the total number of sites counted) increased in 16 species and decreased in two species, broadly correlated with the species changes in numbers.

Conclusion?In most species changes in numbers as well as changes in distribution followed the Western Palearctic population trends. Those species which increased were mainly piscivores and included geese, ducks and gulls. Scarcer species also exhibited an increase in numbers. The changes in numbers (both positive and negative) were more frequent among species associated with running water, whereas species which showed uncertain trends were more frequently recorded on standing water, which is more affected by variable weather conditions.  相似文献   

2.
Daily deaths in ten large cities in the United States were correlated with weather elements for the months of January, April, July, and October of the years 1962–1965. In addition to showing the effects of spells of hot, humid weather and pollution episodes (extreme weather), it was determined that large interdiurnal changes of temperature, dewpoint, and pressure were accompanied by fluctuations in daily mortality. This applies to the northcentral and northeastern United States, where increases in mortality were coincident with prefrontal weather, decreases with postfrontal weather. Total mortality was the cause of death which correlated highest with the weather elements. Deaths over age 70, and under 70, follow in that order. There was little essential difference between arteriosclerotic heart disease and stroke in responsiveness to weather events.
Zusammenfassung Die täglichen Todesfälle in 10 Grosstädten der Vereinigten Staaten wurden mit Wetterelementen der Monate Januar, April, Juli und Oktober der Jahre 1962–1965 korreliert. Es konnte eine Beziehung zwischen Episoden von feuchtwarmemWetter und Luftverschmutzung und Mortalität nachgewiesen werden. Ausserdem ergab sich, dass grosse interdiurnale Schwankungen der Temperatur, des Taupunktes und Luftdruckes von Schwankungen der täglichen Mortalität begleitet sind. In den nordzentralen und nordöstlichen USA fielen Zunahme der Mortalität zusammen mit Vorfronten- und Abnahme mit Nachfronten-Wetter. Die Gesamtmortalität war die Todesursache, die am besten mit den Wetterelementen korrelierte, gefolgt von der Mortalität von Personen über und unter 70 Jahren. Ein wesentlicher Unterschied der Wetteranfälligkeit bei arteriosklerotischen Herzkrankheiten und Schlaganfall bestand nicht.

Resume On a mis en parallèle le nombre journalier de décès survenus dans 10 grandes villes des Etats-Unis et des paramètres météorologiques. L'étude se rapporte aux mois de janvier, avril, juillet et octobre des années 1962 à 1965. On a pu en tirer une corrélation entre les périodes chaudes à atmosphère polluée et une mortalité élevée. En outre, des variations interdiurnes prononcées de la température, du point de rosée et de la pression atmosphérique sont accompagnées de fluctuations marquées de la mortalité. Dans le nord-est, le nord et le centre des Etats-Unis, la mortalité augmente par situations préfrontales et diminue par situations postfrontales. La meilleure relation avec les éléments météorologiques est donnée par le nombre total de décès. Suivent ensuite les décès des gens âgés de plus de 70 ans, puis de ceux qui sont plus jeunes. On n'a par contre pas décelé d'effets météorotropiques marqués ni dans le cas de faiblesses cardiaques artériosclérotiques ni dans le cas d'attaques d'apopléxie.


Condensation of the author's Ph.D. dissertation in meteorology, at the University of Wisconsin, Madison, Wisconsin 1970.  相似文献   

3.
Dynamics of the evapotranspirational demands in the Czech Republic within three decades from 1961 to 1990 has been studied. The determination of the levels of influence of the respective natural components depends on the regionalized modelling techniques. The project of regionalized modelling is theoretically based on the potential evapotranspiration values (ET 0) calculated by FAO methodology (eqs. 1, 2) and the series of temperature and rainfall observations obtained by climatologic stations during a 30-year period from 1961 to 1990 and its relation to the absolute altimetric. The DMR-2 military digital elevation model of the Czech Republic relief consisting of a regular network of points with their altitudes specified in meters was used for the purpose of regionalized modelling. One step of the network in the S-42 coordinate system with the Gauss conforms cylindrical projection is equal to 100 meters; this implies that the smallest area for which the data can be processed is 1 hectare. The digital relief model can be linked to both direct (temperature, precipitation) and derived (evapotranspiration) quantities, which is one of the many novelties of regionalized modelling. The climatic data used in regionalized modelling records daily measurements were obtained by 85 climatologic and rainfall-monitoring stations from 1961 to 1990. Our results showed an appreciable decrease of the most drying area (ratio P/ET0 up to 0.755) in the last decade 1981–90; half as less amounts compared with the previous decade 1971–80 (about 500,000 hectares). On the other hand, an apparent increase (more than 500,000 hectares in comparison with the previous decade 1971–80) of the wettest area (ratio P/ET0 over 1.508) through the last decade was observed. Both first decades 1961–70 and 1971–80 look similar. The project mentioned in this article has made it possible to create models for the different time intervals which have showed higher reliability for heterogeneous application.  相似文献   

4.
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6.
Climate change has affected breeding dates and clutch sizes in many bird species. To date, most of the studies aimed at assessing the effects of climate change on these phenological events in birds have been on hole-nesting species and the changes linked either to local climate variation or to some large-scale composite variables, such as the North Atlantic Oscillation (NAO). Relatively less is known about the climate responses of open-nesting birds and on the relative roles of climate variables at different scales. Using bird ringing records covering a time span of 41 years, we documented shifts in the timing of breeding and brood size in a long-distance migrant, the Red-Backed Shrike (Lanius collurio) from a central European population. We found a 3- to 4-day shift towards earlier breeding and an increase in brood size by approximately 0.3 nestlings since 1964. The Red-Backed Shrikes start to breed in May and rear the first nestlings in June. During the period 1964–2004, temperatures in May significantly increased, while the increase in June temperatures was not significant. Simultaneous tests on the influence of local climate variables and the NAO index revealed a better performance of local climate. The increasing temperature in May was positively associated with the advancement of breeding. Similarly, at a local scale, higher May temperatures were followed by larger brood sizes, while a high amount of rainfall had a strong negative effect.  相似文献   

7.
The paper examines impacts on mortality of heat waves in 2003, the hottest summer on record in the Czech Republic, and compares them with previous similar events. While most summer heat waves over the period since 1986 were associated with significantly elevated mortality, this was not the case for three out of the four heat waves in 2003. The relatively weak mortality response was particularly noteworthy for the most severe heat wave which occurred in the first 10 days of August 2003 and resulted in enormous excess mortality in some western European countries. A mortality displacement effect and short-term adaptation to heat contributed to the reduced mortality impacts of the heat waves that followed after previous relatively warm periods. However, the decreased mortality response of the 2003 heat waves compared to previous heat waves in the 1990s is also likely to have arisen from positive health-care and other socio-economic changes in the post-communist central European region over the past decade, as well as a better public awareness of heat-related risks due to enhanced media coverage and regular biometeorological forecast and warnings.  相似文献   

8.
《Cancer epidemiology》2014,38(1):28-34
BackgroundThe objective of this study was to assess trends in overall and in stage-specific 5-year relative survival rates of the Czech cancer patients between periods 2000–2004 and 2005–2008.MethodsAll Czech cancer patients diagnosed between 1995 and 2008 were included in the analysis. Period analysis was employed to calculate 5-year relative survival for 21 cancers.ResultsSignificant improvements in crude 5-year relative survival for 14 of 21 assessed types of cancer, including the most frequent diagnoses, such as, colorectal, prostate, breast, lung, kidney, pancreatic, and bladder cancer and melanoma, were identified. Moreover, in case of colorectal, lung, and prostate cancer, improvement in stage-specific 5-year relative survival was confirmed as statistically significant for all clinical stages. No diagnosis showed significant decrease in the 5-year relative survival. However, the 5-year relative survival remained poor in patients with metastatic cancers at diagnosis, particularly in case of liver, pancreatic, lung, and oesophageal cancer.ConclusionsThe cancer-specific outcomes in the Czech Republic are improving. Nevertheless, despite the overall significant improvement in 5-year relative survival of most of the cancer diagnoses, the high proportion of patients primarily diagnosed with metastatic cancer still represents a substantial challenge for prevention and early detection.  相似文献   

9.
Questions: Do differences in previous land use cause long-lasting changes in soil chemistry? Is vegetation composition affected by the previous land use after 50 years of secondary succession? Is the effect of previous land use caused by pre-existing differences in environmental conditions or mediated through changes in soil chemistry? How important is the effect of previous land use in relation to other factors? Location: Doupovské Mountains, Czech Republic. Methods: A stratified random sampling design was used to collect 91 vegetation relevés with accompanying soil samples. The effects of previous land use (arable field, meadow, pasture) on soil pH, organic carbon (C), total nitrogen (N), C:N ratio and available phosphorus were tested by an analysis of covariance. A canonical correspondence analysis and variation partitioning procedure were used to reveal relationships among previous land use, environmental factors and species composition. Results: Organic C, total N and C:N ratio were significantly influenced by previous land use, while available phosphorus and soil pH were not. Previous land use explained a significant part of the variation in species composition and its effects only partly overlapped with the effects of soil chemistry and terrain attributes. However, the species composition of post-agricultural forests was mostly determined by environmental factors not modified by previous land use. Conclusions: Forest communities that originate on abandoned agricultural land are primarily determined by natural environmental conditions. Nevertheless, the type of previous land use also modifies the species assemblages of these forests and needs to be considered as an important determinant of their composition.  相似文献   

10.
The Basal Chote? or jugleri Event, close above the Lower–Middle Devonian boundary, has been regarded as a minor but important eustatic transgressive event, which is characterized by significant environmental changes, faunal extinction, appearance of new forms, and maximum radiation, particularly among the goniatites. This study contributes to a more precise stratigraphic allocation of the event, and provides a reconstruction of paleoenvironmental settings in the type area of the event, the Prague Basin (Czech Republic). The beginning of a transgression is recorded already in the T?ebotov Limestone (partitus Zone, Eifelian, early Middle Devonian). The basin-wide change in the sedimentation pattern (onset of peloidal and crinoidal grainstones (calciturbidites) of the Chote? Formation) corresponding to the uppermost partitus and costatus conodont zones, base of Nowakia (Dmitriella) sulcata sulcata dacryoconarid Zone, and Pinacites jugleri goniatite Zone is interpreted here to be linked to a maximum flooding of the basin. A hypothesis of enhanced nutrient load during sedimentation of the Chote? Formation is suggested here as a triggering mechanism for intense micritization and peloid formation and prasinophyte blooms, which could be, along with a greater depositional depth, responsible for oxygen deficiency and consequent reduction of diversity and habitat tracking among benthic invertebrates.  相似文献   

11.
The global climate change may lead to more extreme climate events such as severe flooding creating excessive pulse-loading of nutrients, including nitrogen (N), to freshwaters. We conducted a 3-month mesocosm study to investigate the responses of phytoplankton, zooplankton and Vallisneria spinulosa to different N loading patterns using weekly and monthly additions of in total 14 g N m?2 month?1 during the first 2 months. The monthly additions led to higher phytoplankton chlorophyll a and total phytoplankton biomass than at ambient conditions as well as lower leaf biomass and a smaller ramet number of V. spinulosa. Moreover, the biomass of cyanobacteria was higher during summer (August) in the monthly treatments than those with weekly or no additions. However, the biomass of plankton and macrophytes did not differ among the N treatments at the end of the experiment, 1 month after the termination of N addition. We conclude that by stimulating the growth of phytoplankton (cyanobacteria) and reducing the growth of submerged macrophytes, short-term extreme N loading may have significant effects on shallow nutrient-rich lakes and that the lakes may show fast recovery if they are not close to the threshold of a regime shift from a clear to a turbid state.  相似文献   

12.
A previous analysis of the radon-related lung cancer mortality risk, in the German uranium miners cohort, using Poisson modeling techniques, noted internal (spontaneous) rates that were higher on average than the external rates by 16.5% (95% CI: 9%; 24%). The main purpose of the present paper is to investigate the nature of, and possible reasons for, this difference by comparing patterns in spontaneous lung cancer mortality rates in a cohort of male miners involved in uranium extraction at the former Wismut mining company in East Germany with national male rates from the former German Democratic Republic. The analysis is based on miner data for 3,001 lung cancer deaths, 1.76 million person-years for the period 1960–2003, and national rates covering the same calendar-year range. Simple “age–period–cohort” graphical analyses were applied to assess the main qualitative differences between the national and cohort baseline lung cancer rates. Some differences were found to occur mainly at higher attained ages above 70 years. Although many occupational risk factors may have contributed to these observed age differences, only the effects of smoking have been assessed here by applying the Peto–Lopez indirect method for calculating smoking attributability. It is inferred that the observed age differences could be due to the greater prevalence of smoking and more mature smoking epidemic in the Wismut cohort compared to the general population of the former German Democratic Republic. In view of these observed differences between external population-based rates and internal (spontaneous) cohort baseline lung cancer rates, it is strongly recommended to apply only the internal rates in future analyses of uranium miner cohorts.  相似文献   

13.
Abstract

The relationships between length of the interpregnancy interval, outcome of the pregnancy preceding the interval, sex of the infants, pregnancy order, maternal age, and maternal history of previous child deaths and neonatal and postneonatal mortality were explored in a rural Bangladeshi population using a multiple regression analysis. Specific interactions between the interpregnancy interval, outcome of the pregnancy preceding the interval, sex of the infants, and history of previous child deaths were examined. An inverse relationship was observed between postneonatal mortality and the length of the interpregnancy interval when the pregnancy preceding the interval was a surviving infant. No such trend was observed for neonatal mortality. Post‐neonatal mortality rates among children whose mothers had experienced two or more previous child deaths were essentially the same as that for infants whose mothers had experienced 0–1 child deaths when the interpregnancy intervals were more than 24 months. Although female infants have a lower neonatal mortality than male infants, the neonatal mortality rate for female infants conceived less than twelve months following a male infant birth was higher than for a male infant conceived less than twelve months following another male infant birth. Post‐neonatal mortality is consistently higher for female compared to male infants in all interval categories.  相似文献   

14.
Hédl  Radim 《Plant Ecology》2004,170(2):243-265
From 1941–;1944 nearly 30 phytosociological relevés were completed by F. K. Hartmann in the Rychlebské Mountains, a typical mountainous area in northeastern Czech Republic. Of the original plots still covered with adult grown beech (Fagus sylvatica) forest, 22 were resampled in 1998 and 1999. In order to describe the recent vegetation variability of the sites 57 relevés were recorded. Changes in vegetation were estimated using relative changes in species density and ordinations (PCA, RDA). Environmental changes were assessed using Ellenberg indicator values when no direct measurements were available. A decline in species diversity has been documented, particularly, many species occurring frequently in deciduous forests with nutrient and moisture well-supplied soils around neutral have decreased. In contrast, several light-demanding, acid- and soil desiccation-tolerant species have increased. Natural succession, quantified as forest age, contributed slightly to these changes. In Ellenberg indicator values, a decline in F (soil moisture), R (soil calcium) and N (ecosystem productivity), and an increase in L (understorey light) were shown. This is interpreted as the influence of modified forestry management and of airborne pollutants. Intensified logging caused the canopy to open and soil conditions to worsen. The latter is most likely also due to acid leaching of soil cations (Ca, K, Na). This caused a decline in soil productivity, thus the effect of nitrification could not be detected. The original relevés may have differed in size influencing the results. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

15.
The occurrence of toxigenic fungi producing aflatoxins and ochratoxin A in foodstuffs was studied in the Czech Republic. Twenty five commodities were collected at twelve collection places in the Czech Republic (300 food samples). The presence of potentially toxigenicAspergillus flavus was observed in 28% of the sampled foods (black pepper, caraway seeds, fruit tea, black tea, oat flakes, fine flour, rolled oat flakes and semolina) in the year 1999, and in 25% of the sampled foods (black pepper, black tea, fine flour) in the year 2000.A tamarii (aflatoxins producer) was found in 3 black pepper samples (25%) in both years. Aflatoxins were detected in black pepper and caraway seed samples in the year 1999 and in sweet red pepper in the year 2000.A parasiticus andA nomius were not isolated. Aspergillus section Nigri (potential producer of ochratoxin A) was detected in some foodstuffs. Ochratoxin A was detected in raisins.Penicillium verrucosum andA ochraceus were not isolated from foodstuffs.  相似文献   

16.
Quaternary limnic sediments from Velanská Cesta, a former lake in the Czech Republic, were investigated to document the response of an aquatic environment to global climatic shifts during the late Pleistocene–early Holocene transition. The obtained multi-proxy record, including subfossil diatoms, diatom-inferred variables (index of trophic state, halobic index, TP, and pH), plant macrofossils, and geochemical data, was compared with the δ18O GISP2 curve. Diatom accumulation zones and subzones established on the basis of a ConSLink cluster analysis corresponded well with the boundaries of the Bölling, Older Dryas, Alleröd, Younger Dryas, and Preboreal periods. The diatom-inferred trophic state and salinity data showed increased values during the colder epochs, which were supported by the findings of low-temperature macrofossil indicators in the corresponding samples. The results of this study document a long-term forcing of a shallow lacustrine ecosystem in central Europe by climatic events of a global scale.  相似文献   

17.
Abstract

Empirical evidence has consistently documented the direct relationship between infant mortality and socioeconomic inequality in the United States and numerous other countries. While the majority of these studies reveal an inverse relationship between socioeconomic level and infant mortality, not even this finding is free from disagreement. Furthermore, the specific nature and magnitude of this relationship has varied over time.

This study will examine the relationship between socioeconomic status and infant mortality in metropolitan Ohio by using birth and infant death data centered on the 2000 Census. The analyses presented herein will describe and analyze the relationship between infant mortality and socioeconomic status in metropolitan Ohio in the year 2000. The key finding is that in spite of remarkable declines in infant mortality during the past several decades, most notably in neonatal mortality, there continues to be a pronounced inverse association between the infant death rate and the economic status of a population.  相似文献   

18.
Factors determining the invasibility of different types of anthropogenic vegetation were studied in the Czech Republic. A data set of 3420 vegetation plots recorded between 1945 and 2005, containing 913 species, was used. A set of climatic variables (mean annual temperature and precipitation, together with elevation), propagule pressure (substituted by human population density) and local habitat conditions (substituted by values of CSR life strategies and Ellenberg indicator values of native species) was obtained for each plot. All species were classified as native, archaeophytes (i.e. alien species introduced before 1500), and neophytes (i.e. aliens introduced after 1500) and their relative proportion was calculated for each plot. Regression tree models were used to determine the ecological characteristics of the most invasible man-made habitats in the Czech Republic. The plots contained on average 31.9% archaeophytes and 7.3% neophytes. Correlation between the proportions of archaeophytes and neophytes was positive and significant. Both archaeophytes and neophytes were found predominantly in strongly disturbed habitats with a high nutrient supply located at low elevations in warmer climatic areas of the Czech Republic. Archaeophytes are more influenced by local habitat conditions and preferentially colonize sunny and dry man-made habitats with higher soil reaction. Neophytes have no special preferences for local habitat conditions and their highest proportion was found mainly in disturbed habitats at low elevations. Our results show that for anthropogenic vegetation in the Czech Republic, ecological and habitat characteristics are more important factors for plant invasions than different land use in the surrounding area.  相似文献   

19.
Armillaria cepistipes and A. gallica (Basidiomycota, Physalacriaceae) are morphologically similar species, and they are often nearly indistinguishable using DNA-based methods targeting the ITS region of ribosomal DNA. The aim of this study was to examine morphological and ecological features of A. cepistipes and A. gallica, and to test other DNA-based methods to distinguish the two species. Our results revealed discriminative macro- and micromorphological features between these two species, especially the presence of a distinct central pileus ocella, the shape of the annulus, the character of the velar stipe remnants and the length of the terminal cells of the pileus scales. Ecologically, A. gallica generally prefers warmer areas in lowlands (oak and alluvial forests), while A. cepistipes is more common in hilly and lower montane beech forests in Central Europe. Nevertheless, despite differences in ecological preferences, certain locations between 300 and 500 m a.s.l. are known to sympatrically support both species. The sequences of the translation elongation factor 1-alpha showed high interspecific variability, and this gene is a more appropriate candidate for distinguishing A. gallica from A. cepistipes.  相似文献   

20.
Grassland seed banks are traditionally considered a source of new species in degraded communities. However, many recent studies have shown that the potential of the seed bank to restore many communities is rather limited. Two principal reasons for these limitations, loss of species from the seed bank or inability of the species to create any seed bank, are, however, usually not distinguished. This study aims to assess the role of seed bank composition and heterogeneity in the restoration of species-rich plant communities. It was carried out in mountain grasslands in the eastern part of the Krkono?e Mountains, Czech Republic. The composition of vegetation and seed bank were recorded and their relationship was assessedin 1.5m × 1.5 m plots placed in non-degraded and degraded parts of seven grasslands. Vegetation at currently managed sites is not degraded; degraded parts were without management (dominated byHolcus mollis, Bistorta major orRumex alpinus). The degree of heterogeneity of seed bank and vegetation was tested as the relationship between subplot similarity, distance, and degradation stage. Degradation had significant effects on composition of both aboveground vegetation and seed bank and increased heterogeneity both in the vegetation and in the seed bank. Species absent from the vegetation of degraded plots were also absent from the seed bank of both degraded and non-degraded plots, indicating that the absence of species from the seed bank is not due to their loss during the degradation process but rather due to the low number of seeds in the seed bank already in the non-degraded communities. Furthermore, the seed bank of the degraded communities largely results from the present vegetation of these communities. This supports the limited role of the seed bank in these communities. Restoration of these sites is thus impossible unless management will include methods with which seeds will arrive at the degraded sites.  相似文献   

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