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An attempt was undertaken in this work to characterize the imission field of the PM10 particulate matter in the Warsaw area, based on measurements coming from 11 stations located in area, and from 4 stations outside Warsaw belonging to the Voivodship Inspectorate of Environmental Protection in Warsaw. The analysis concerns the 2004-06 period. Basic descriptive statistics of the concentration were calculated, the daily (24 hrs) averaged courses were studied in the whole experimental period for the cold (Oct.-March) and warm (April-Sept.) seasons, rose diagrams of particulate matter concentration percentages and of pollution plume rate percentages were made, and an effort to visualize the spatial distribution of particulate matter over the Warsaw area was made, on the basis of PM10 particulate matter concentration values registered at the stations mentioned above. As a result of the executed analyses it was found that the existing measurement network of PM10 is insufficient for a precise recognition of the imission field. It is necessary not only to extend the network of monitoring stations, especially in the Warsaw districts located on the right bank of the Vistula River, but also to include all vital meteorological parameters and particulate matter qualitative analyses into the range of measurements. In relationship to a high level of PM10 concentrations occurring in the area of the whole city, the authors propose publicizing measurement results. The analysis of pollution plumes, which was possible only for two monitoring stations located in the northern and southern parts of the city, enabled the authors to focus on substantial causes for increased PM10 concentration in that regions.
The dependence of the content of various forms of nitrogen and absorption of N by cocksfoot grass on meteorological conditions was established in a field experiment. Correlations between the content of total nitrogen, protein nitrogen, N-NH4, and N-NO3 in sward and roots of cocksfoot grass and some meteorological elements, i.e. maximum temperature, minimum temperature, average daily temperature measured at 5 and 200 cm, air relative humidity, cloud cover, sum of precipitation, sum of evaporation and soil temperature measured at a depth of 2, 5, 10, 20 cm were analyzed. Correlation coefficients between the forms of nitrogen in the plant and the above meteorological elements were calculated, as well as multiple regression equations, multiple correlation coefficients and determination coefficients. No significant relationship between the forms of N (Ntotal, Nprotein, N-NH4, N-NO3) in sward and roots of cocksfoot grass and the course of meteorological conditions was clearly stated. The relationship between the content of N-NH4 in sward and Ntotal and N-NO3 in roots, and certain meteorological elements is relatively small and can be characterized by the value of determination coefficients, i.e. 0.166, 0.106 and 0.151, respectively. According to the statistical analysis, the absorption of nitrogen by cocksfoot grass depends to a relatively small though significant extent (R2=0.249) on certain meteorological elements. However, further research is still recommended.
The parameters of the birch pollen seasons in Cracow in 1991-2008 were analysed in relation to some meteorological elements and synoptic situations (circulation types, air masses and atmospheric fronts). Two types of the pollen seasons were distinguished – highly dense and less dense. The first type of the season started on the 15th of April (on average), lasted 11-20 days and the maximum daily concentration exceeded 500 pgm-3. The less dense type started generally earlier (the first decade of April), lasted more than 20 days and the peak days were unstable. In this type of the pollen season, two peak days were often observed. The relationship between the type of the season and the meteorological conditions before the season was pointed out. Additionally, the influence of circulation types, types of air masses and atmospheric fronts over south-eastern Poland on a given day on the number of days with a daily concentration > 80 pgm-3 was analysed. The relationship between the pollen season type and meteorological conditions before the season was found, among others, the influence of types of synoptic situations and air masses on the number of days with a concentration of over 80 pgm-3 was established.
The paper refers to the estimation of Poaceae pollen seasons in Poland in selected areas. The aim of the study was to present the long-term variability of the start, end and duration of grass pollen seasons and the seasonal pollen index (SPI) in Poland against a background of the meteorological conditions over pollen seasons. The study was performed in eight Polish cities in 1992–2014 (the common seasons were 2003–2012). Pollen season start was relatively stable in the studied period, the seasons began about the 10th of May, a bit earlier in the south part of Poland. Pollen season ends were more changeable in comparison to the season start and fluctuated from the middle of July to the middle of September. SPI clearly depended on temperature and precipitation in April–August. Daily maximum pollen concentrations were achieved between the end of May and the first decade of July and no evident relationship between this day and weather conditions was found, apart from 2004.
Mass wasting is one of the most important processes influencing the shaping of mountain slopes. Most programs for testing mass wasting are limited to short-time, single observations, and to surface measurements of the big phenomenon ignoring shallow landslides occur resulting in slope covers, or on its border with the rock solid. That is why, when analyzing the causes of mass wasting processes, it is extremely important to assess the infl uence of meteorological conditions on water circulation in the landslide slope system and the status of stresses in a soil medium that is connected with it. The aim of this work was to determine the course of changes in stability conditions for two selected slopes, connected with meteorological conditions in the period of 2009–2013 on the area of the Wiśnicz Foothills. Numerical analysis were subjected to two slopes in villages the Królówka and the Łychów. Meteorological data for analysis, i.e. air temperature and soil humidity, wind speed, precipitation sum and length, were taken from the station Jagiellonian University in Łazy. To determine the course of changes of stability factor used capabilities Geostudio 2007 (Slope/W, Vadose/W, Seep/W). The work is a pre-development servant indicate the formation of shallow landslides present in silt. Results of the stability calculations confi rmed the common opinions that conditions of slope balance are very strongly connected with atmospheric precipitation, but it was also shown that they also depend signifi cantly on thermal conditions. These calculations showed that in the period 2009–2013 the most unfavorable conditions of stability were obtained in May 2010, which is a confi rmation of the situation observed in reality.
This work uses the results of Post-registration Cultivar and Agricultural Experimentation conducted in 1999–2011 in Lower Silesia, on soils of very good and good wheat complex. The rape vegetation season was divided into five periods that approximately corresponded to the phenological phases of the plant, namely: September-November (from sowing to stemming the growing season in the autumn), December-March (stunted vegetation – renewal of vegetation), April (renewal of vegetation – the beginning of flowering), May (flowering), June (end of flowering – technical maturity). In the constructed regression model the following factors were included: the average air temperature and total precipitation in the periods, the content of phosphorus, potassium and pH of soil and fertilization with nitrogen, phosphorus and potassium. Comparing the impact of meteorological conditions in different growing periods of winter rape, it was found that the weakest impact on the yield had temperature and precipitation from September to November. During this period, the optimum for yield are the following conditions: average temperature 10.4°C and precipitation total 145 mm. The winter period (December- March) has the strongest impact on the yield of rape. The yield is conspicuously higher with lower average air temperatures. Optimal for yield is precipitation of 171 mm (highest tested) and a relatively low average air temperature (–0.9°C). In April, the decisive factor is rainfall. Its lower values (12 mm) favour higher yield. The optimum weather in this period is 12 mm precipitation and average temperature of 9.1°C. Rape yield increases with increasing average air temperature in May and is highest when its value is 15°C and rainfall in this month is above average (73 mm). The weather in June has less impact on rape crop than in the three previous periods. The optimal layout is: 27 mm precipitation and temperature 16°C, these values being the smallest tested.
Since 1992 lidar-based measurements have been carried out under various meteorological conditions and at various times of the year. The aerosol optical properties were determined in the marine boundary layer as a function of altitude using such factors as wind direction, duration and velocity and aerosol size distribution and concentration. It was confirmed that in all cases, the total aerosol concentration, size distribution and aerosol extinction increase with wind speed but decrease with altitude. In the range of wind velocities from 1 to 15 m s−1 the mean aerosol optical thickness of the atmosphere (VIS) obtained from the lidar varied from 0.1 to 0.38 for offshore winds and from 0.01 to about 0.1 for onshore winds, while the ˚Angstr¨om parameter for VIS oscillated around 0.65 for onshore winds and around 1 for offshore winds. Both parameters depended strongly on the history of the air mass above the Baltic Sea. Such aerosol optical thicknesses are in agreement with those obtained by other researchers in the Baltic Sea area.
The aim of the present study was to analyse the Rumex pollen season dynamics in Lublin in 2001-2010 and to find relationships between season parameters and meteorological conditions. This study was carried out by the volumetric method using a Lanzoni VPPS 2000 trap. The start and end dates of each season were determined based on the 98% method. The effects of meteorological factors on the Rumex pollen seasons were analysed by employing Spearman’s correlation test. On average, the sorrel pollen season started on 13 May (±7 days), ended on 7 September (±6 days), and lasted nearly four months (±9 days). The highest pollen concentrations were recorded in June and July. A significantly negative correlation was found between season duration and Seasonal Pollen Index (SPI). During shorter pollen seasons, higher pollen counts were recorded. In all study years, the seasons were right-skewed. The pollen concentration was most strongly correlated with humidity and mean air temperature. The season parameters (onset, end, peak date, peak value, SPI value) were primarily dependent on air temperature before and during the pollen season.
The project presents research involving an analysis and evaluation of water supply of poorly permeable soils in drained arable lands. The analysis dealt with research conducted in 2003–2005 at similar meteorological conditions in an agricultural submountain catchment area situated in Central Sudety. In particular, the analysis concerned water and air properties of examined deposits with regard to their water-retention. The measurements of moisture density of soil profi les and calculated water supplies in layers 1–100 cm showed a crosssection of reserves of soil retention. This depended on the depth and lay of the land as well as drainage conditions. In the lower drainage area at the foot of the slope there was a notably higher level of groundwater than in other places on the slope. In areas where rainfall was the exclusive source of groundwater the measured water-supplies were lower than in multi-sourced drainage areas. The amount of measured supplies for the vegetation period spanning the whole research time was not lower than 70% of the fi eld-water capacity.
The main aim of the paper is to present general information about hydro-meteorological conditions in the catchment of the Łebsko Lake. In the first part of the article a short description of the most important hydrographic elements of the investigated area (the Łebsko Lake, the Łeba River and its tributaries) was provided. The climatic analysis of local conditions, besides the characteristics of the air temperature and precipitation, contains the distribution of other principal meteorological elements (pressure, wind, cloud cover or relative humidity). The paper is a part of broader studies aimed at finding the key factors determining seasonal and annual changes of water relations in the catchment of the Łebsko Lake.
The paper presents the analysis of changes in weed infestation in spring barley cultivated in the years 1990–2004 in crop rotation with a 25% proportion of this cereal (potato – spring barley – sowing peas – winter triticale), when it was grown after potato, and in crop rotation with its 75% proportion (potato – spring barley – spring barley – spring barley), when it was grown once or twice after spring barley. In the experiment, no weed control was applied. Every year in the spring (at full emergence of the cereal) and before the harvest, the composition of weed species and weed density of particular weed species were determined, and before the harvest also their biomass. Weed density increased linearly on all plots during the 15-year period. The average values confirm the increase in weed biomass in the case when spring barley was grown once or twice after this crop; however, those differences were influenced by the previous situation only during some seasons. Weed density and biomass showed high year–to–year variability and a positive correlation with the amount of precipitation and a negative correlation with temperature during the period of the study. A negative correlation between the yield of barley and weed biomass was shown.
The main aim of this work was to determine the changes of meteorological conditions in Poznań, Poland, in the period 1848-2009. The onset of the analyzed period coincides with the launch of conducting instrumental meteorological measurements in Poznań. Professor Smosarski’s analyses and data were taken into account for the examination of the period 1848-1922, while data from NOAA and the Meteorological Yearbooks were applied for the years 1960-2009. It has been concluded that the mean annual temperature for the period 1848-1922 was 0.9°C lower than for 1960-2009, while for 2000-09 it was as much as 1.9ºC higher. It also has been established that a period without ground frost incidences was prolonged and the frost season shortened. Koeppen’s criterion was used to determine the frequency of the conditions leading to landscape stepping.
Decomposition is an important carbon flux that must be accounted for in estimates of forest ecosystem carbon balance. Aim of this research is to provide estimate of fine woody debris decomposition rates for different tree species and sample sizes also taking into account the influence of specific microsite meteorological conditions on decomposition rates. In this paper we present results of the first two years of the experiment designed to last six years. Study was conducted in managed lowland oak forest in central Croatia. Decomposition rates (k) of fine woody debris (diameter 0.5–7 cm) for four species (Querus robur L., Carpinut betulus L., Alnus glutinosa Gaernt., Fraxinus angustifolia L.) in four size classes were estimated using litter bag method and mass loss equation of Olson (1963). Overall average k in our study was 0.182 ± 0.011 year-1. Results indicate that decomposition rate is affected by the size of the debris, with the smallest diameter branches (<1 cm) decomposing is significantly faster (k = 0.260 ± 0.018, P <0.05) than the larger one. Tree species from which debris had originated also affected decomposition, although to a lesser extent, with hornbeam samples having significantly (P <0.05) higher average decomposition rate (0.229 ± 0.028), compared to that of ash samples (0.141 ± 0.022). Proportion of variability in k explained by variables ‘species’ and ‘size class’ was assessed with general linear model (R² = 0.644) also taking into account variables like soil temperature and soil water content. Sample size class explained 22.2%; species explained only 9.4%, while soil water content and temperature combined explained 32.8% of the variance of k. Rate constants obtained within this study might be useful in modelling ecosystem carbon balance for similar lowland forest ecosystems in Europe.
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