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The seasonal distribution of fungal spore concentration in the city of Porto, Portugal, was continuously studied, from 1 January to 31 December 2003, using a 7-day volumetric Burkard trap. In Portugal, aerobiological studies are scarce, and to our knowledge there are no published data on the atmospheric concentration of fungal spores. The aim of this work therefore is to initiate the aeromycological studies in Porto. The total airborne spore concentration fluctuated between 2 and 2,198 spores/m3 per day with an daily mean of 403 spores/m3. The highest airborne spore concentration was found during the summer and the early autumn, while the lowest concentration was registered during the winter. A range of allergenic and phytopathogenic fungal spores was present in the atmosphere of Porto throughout the entire year, although in different concentrations. Among the 22 fungal spore types identified Cladosporium (74.5%), Ganoderma (11.7%), Aspergillaceae (2.9%), Ustilago (2.5%), Coprinus (1.5%), Alternaria (1.3%) and Botrytis (1.3%) were the most frequent. Seasonally, spore levels of Cladosporium and Alternaria peaked in the autumn and winter, Ganoderma peaked toward autumn, whilst spore levels of the basidiomycete Coprinus fluctuated throughout the year. The total spore concentration was negatively correlated with wind speed and positively correlated with temperature and relative humidity.
Results of 10-years runoff plot experiments carried out on two sites of the Lublin Upland were presented. Despite similar soils and climatic conditions, studies showed large differences in annual soil erodibility (K factor of the USLE) between both sites. Experimentally derived values of the factor were dependent on tillage direction and time of maintaining runoff-plots in fallow conditions. On a site cultivated in contour direction, 4-year period was insufficient to achieve K values similar to the predicted values from the USLE. In contrast to this, on a site cultivated up-down slope, similar experimental and predicted K values were obtained after 2 years and remained at the same level during next 4 years. Results enabled to identify limitations of the USLE application for erosion prediction in Poland. Studies proved that soil erodibility could be used for prediction of erosion risk for silt loam developed from loess. However, application of soil erodibility approach to the event–base models is questionable for variation of K factor in the initial years. As far, the factors affecting soil erodibility changes are not recognized and need further research.
The present paper concentrates on the basic features of an annual precipitation course (monthly, seasonal and annual sums) registered between 1861-2000. The paper also defines an amount of precipitation sums’ deviations from the many years’ average, factor of monthly precipitation sums’ changeability and trends of their changes. The characteristics of the annual precipitation sums in an annual course allow to define which months, seasons and half-years were characterized by more intensive changeability and discover if there was recorded a considerable asymmetry between the particular months, seasons and half-years and what were the reasons of the asymmetry.
Pollen concentration in the atmosphere of Vinkovci (northeastern Croatia) has been analyzed using a Hirst-type volumetric spore trap. During the year 2005, 58 pollen types were recorded with the sum of annual totals of 14,011. The pollen spectrum refl ected the fl oristic diversity of the region. Non-arboreal pollen predominantly contributed to the total pollen sum with a percentage of 81.80%. The main pollen producers characterized by allergenic pollen were: Betula, Quercus, Fraxinus, Populus, Pinus, Urticaceae, Ambrosia, Poaceae, Plantago and Artemisia. Urticaceae was the most frequent and most abundant pollen type accounting for 46.58% of the total annual pollen, followed by Ambrosia (19.66%) and Poaceae (11.01%).
To study variation in the diet of the raccoon dogNyctereutes procyonoides Gray, 1834 in northern Belarus, 3299 scats were sampled from 18 localities differing in habitat quality. In one of the 18 localities, the dietary study was conducted for nine years. The data obtained was analysed according to seasonality, between-year difference, family specificity and habitat influence. In northern Belarus, the raccoon dog was found to be a generalist predator with omnivorous and opportunistic feeding habits. Their diet was highly variable, but a common trait was specialization on carrion in winter and on berries in late summer. Beside carrion and berries, the other seasonally important food items were frogs, insects, plant matter, mammals, and birds. The diet varied between seasons and habitats. In the warm season, habitat factors, such as type of soil (clay or sand), proportion of lakes and open grassy marshes, seemingly determine the food supply for raccoon dogs, and thereby influence the diet of individuals. The obtained results on dietary variation of raccoon dogs can be used in detailed analysis of the impact of this introduced species on native fauna and its role in functioning of vertebrate communities.
In a mosaic landscape moderately affected by agriculture and tourism, such as found in the Masurian Lakeland (north-eastern Poland) external input of nutrients (TP, TN, NNO3) and their retention were compared in a cascade of shallow in-river lakes, between several years of different weather conditions. The average and maximum air temperature in the summer and winter months and that of the freshet (April) tended to be higher in the late 90s than the late 70s. The annual summer precipitation was lower in some years of the 90s than the 70s. This combination of dry and warm conditions (especially in summer) resulted in the water discharge, renewal rate of lake water and nutrient loads to the lakes becoming drastically reduced and more differentiated between freshet and other periods. This imbalance resulted in the occasional higher concentration of nutrients (due to internal loading) in lake outflows and lower retention of nutrients in the lake systems. Downstream exports of TP or TN took place occasionally from the lakes, although N-NO3 was usually retained. Speculations are made about how frequently this situation may affect surface-fed, shallow lakes in the light of global warming (already detected in the region) and how important this could become for future eutrophication in shallow, temperate lakes generally.
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