Research on urban climates has been an important topic in recent years, given the growing number of city inhabitants and significant influences of climate on health. Nevertheless, far less research ...has focused on the impacts of light pollution, not only on humans, but also on plants and animals in the landscape. This paper reports a study measuring the intensity of light pollution and its impact on the autumn phenological phases of tree species in the town of Zvolen (Slovakia). The research was carried out at two housing estates and in the central part of the town in the period 2013–2016. The intensity of ambient nocturnal light at 18 measurement points was greater under cloudy weather than in clear weather conditions. Comparison with the ecological standard for Slovakia showed that average night light values in the town centre and in the housing estate with an older type of public lighting, exceeded the threshold value by 5 lux. Two tree species, sycamore maple (Acer pseudoplatanus L.) and staghorn sumac (Rhus typhina L.), demonstrated sensitivity to light pollution. The average onset of the autumn phenophases in the crown parts situated next to the light sources was delayed by 13 to 22 days, and their duration was prolonged by 6 to 9 days. There are three major results: (i) the effects of light pollution on organisms in the urban environment are documented; (ii) the results provide support for a theoretical and practical basis for better urban planning policies to mitigate light pollution effects on organisms; and (iii) some limits of the use of plant phenology as a bioindicator of climate change are presented.
Environmental degradation, for example, by wind erosion, is a serious global problem. Despite the enormous research on this topic, complex methods considering all relevant factors remain unpublished. ...The main intent of our paper is to develop a methodological road map to identify key soil–climatic conditions that make soil vulnerable to wind and demonstrate the road map in a case study using a relevant data source. Potential wind erosion (PWE) results from soil erosivity and climate erosivity. Soil erosivity directly reflects the wind-erodible fraction and indirectly reflects the soil-crust factor, vegetation-cover factor and surface-roughness factor. The climatic erosivity directly reflects the drought in the surface layer, erosive wind occurrence and clay soil-specific winter regime, making these soils vulnerable to wind erosion. The novelty of our method lies in the following: (1) all relevant soil–climatic data of wind erosion are combined; (2) different soil types “sand” and “clay” are evaluated simultaneously with respect to the different mechanisms of wind erosion; and (3) a methodological road map enables its application for various conditions. Based on our method, it is possible to set threshold values that, when exceeded, trigger landscape adjustments, more detailed in situ measurements or indicate the need for specific management.
The occurrence of drought during flowering (usually from the end of May to the beginning of June) is the most hazardous timing in terms of the possible negative impact of agricultural drought on ...winter wheat, which is the most cultivated crop in the Czech Republic (about 800000 ha). Lack of water, often accompanied by high temperatures, negatively affects the number of grains in the wheat ear and the tissue development of the developing grain, with consequent impacts on yield and quality of product. With the use of a) long-term time series of agrometeorological data (1961–2010), b) long-term phenological time series of winter wheat (1981–2010), and c) soil conditions data (available water capacity of soils of the Czech Republic) for the arable soil, the ratio of actual evapotranspiration and potential evapotranspiration for the period of 1961–2010, used as an indicator of agricultural drought (lack of water) for wheat, was calculated. The innovative aspect of this categorization of the territory of the Czech Republic according to the risk of occurrence of agricultural drought for winter wheat is considering drought from the aspect of the plant, i.e., evaluation based on the actual consumption of water by the vegetation. This is a very sophisticated procedure. Frequently, water content in soils data, presented as an output of some models, do not fully indicate the possible negative impacts on yield generation because the plants themselves are typically not considered. The method used in this study is universally applicable and allows comparisons of regions at the local, regional, and supra-regional levels. For estimation of the development of agronomic drought in the future, the basic water balances in the growing seasons of 1961–2010 and 2071–2100 were compared using a climate scenario. The forecast indicates a significant deterioration of agricultural drought in the region with probable direct impacts on agricultural production.
The positive effect of nitrogen fertilization in agriculture inevitably increases residual nitrogen losses. Water pollution led to legal restrictions of some farm practices within the framework of ...the Nitrates Directive of the EU. Nevertheless, even several decades later, the situation has not improved significantly. We present a possible science-based explanation of such a state and provide it to farmers and government as a support for environmental management settings. This study aimed to compare an established approach to implementing the Nitrates Directive, specifically the climate-based zoning of nitrogen fertilization restrictions using data from the mid-20th century. We evaluated this approach by juxtaposing the initial climate data with more recent data spanning from 1991 to 2020. Subsequently, we examined this zoning framework from the perspective of the non-vegetative period, characterized by temperatures below 5 °C, which is widely acknowledged as a critical threshold for nitrogen intake by plants. We found out that i) the employed climate-born zoning does not correspond to recent climate data; ii) nonvegetation period is longer than nitrogen fertilization restrictions. Therefore, despite a noteworthy 22 day reduction in the nonvegetation period from 1961/1962 to 2019/2020, we cast doubt on the notion that the period limiting nitrogen fertilizer application should also be shortened, while admitting that there are other abiotic and biotic factors affecting nitrogen behaviour within the ecosystem.
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•Nitrogen management in the Czechia affects water quality of 11 states.•Continuous unsatisfactory water quality calls for Nitrates Directive scrutiny.•We bring climatologically based contribution to the discussion on nitrogen management.•Vegetation period in Central Europe has prolonged about 20 days over last 6 decades.•Nitrogen application bans and nonvegetation period differ about tens of days.
Differences in transpiration of maize (Zea mays L.) plants in four soil moisture regimes were quantified in a pot experiment. The transpiration was measured by the “Stem Heat Balance” method. The ...dependence of transpiration on air temperature, air humidity, global solar radiation, soil moisture, wind speed and leaf surface temperature were quantified. Significant relationships among transpiration, global radiation and air temperature (in the first vegetation period in the drought non-stressed variant, r = 0.881**, r = 0.934**) were found. Conclusive dependence of transpiration on leaf temperature (r = 0.820**) and wind speed (r = 0.710**) was found. Transpiration was significantly influenced by soil moisture (r = 0.395**, r = 0.528**) under moderate and severe drought stress. The dependence of transpiration on meteorological factors decreased with increasing deficiency of water. Correlation between transpiration and plant dry matter weight (r = 0.997**), plant height (r = 0.973**) and weight of corn cob (r = 0.987**) was found. The results of instrumental measuring of field crops transpiration under diverse moisture conditions at a concurrent monitoring of the meteorological elements spectra are rather unique. These results will be utilized in the effort to make calculations of the evapotranspiration in computing models more accurate.
Official price of farmland in the Czech Republic is based on land value in different soil and climatic conditions. The paper compares relevant climatic and agroclimatic characteristics used for land ...appraisement. Characteristics defined in climatic region of estimated pedological ecological unit system for two fifty years period 1901-1950 and 1961-2010 were evaluated. Area of interest includes 53 points distributed within nine broad areas of the Czech Republic. It is evident that the development of climate has an enormous impact on soil fertility. Difference of station average values of air temperature of both fifty years vary from −0.5 to 1.1 ◦ C (mean difference is 0.3 ◦ C) in the case of vegetation period. The shift of precipitation is not so evident as in the case of temperature. The long term change in precipitation distribution within a year is documented by a different shift of annual, vegetation period and non-vegetation period values. Moisture certainty in vegetation period decreases in all cases of broad areas (except one region). All 50year averages of investigated parameters had been changed in 1961-2010 compared to the mean of 1901-1950. This should be taken into account when fixing the official price. Climatic region parameters should be replaced by a more complex “agroclimatological characteristic”, which take into account also the basic pedological and plant characteristics, for example the available water holding capacity.
Urban environment differs from the surrounding landscape in terms of the values of meteorological parameters. This is often referred to as the urban heat island (UHI), which in simple terms means ...higher air temperatures in cities. The cause of these changes lies in the different active surfaces in cities, which subsequently results in a different radiation balance. The higher temperatures, however, also affect the living conditions in the city and during very high temperature periods can have negative effects on the health of the city inhabitants. The results presented in this paper are based on measurements taken over several years at locations near Hradec Králové, which is surrounded by different surface areas. Environment analysis was performed using the Humidex index. The obtained results show that replacing green areas with built-up areas affects temperatures in the city, when air temperatures are very high they significantly increase the discomfort of the inhabitants. Differences in the frequency of discomfort levels are observed especially during periods of high temperatures, at lower temperatures these differences are not significant. Higher frequencies of discomfort are observed at locations with artificial surfaces (asphalt, cobblestones, concrete) and in closed spaces. In contrast, locations with lots of green areas almost always have the value of this index lower or more balanced. The results should therefore be a valid argument for maintaining and extending green areas in cities.
To evaluate soil moisture conditions in spring crops sowing term, data of bare soil surface state were used. Analysis included 32 stations throughout the Czech Republic. Number of days with dry soil ...surface in each year was compared with the average number of those days in the period 1961-2010 for a given station. The limits of the individual categories were then determined for the period 1961-2010. The individual values of the number of days with dry condition of soil in the early spring period were compared with acquired 10th, 25th, 75th and 90th percentile average (1961-2010). More days with dry soil are usually observed in April than in March. In both months there are 11 days with this condition of soil altogether on average. Dry early spring occurred mainly in 1961, 1968, 1974, 1981, 1990, 2002, 2003, 2007 and 2009. Wet spring occurred in years 1965, 1970, 1980, 2001 and 2006 at almost all stations. There is a significant correlation (p < 0.01) between number of days with dry condition of soil and elevation (r = −0.51, n = 32). Average number of days with dry condition of soil surface in March and April in the period 1961-2010 ranges from 5 to 21 days, which is similar to the median values. Trend analysis did not produce conclusive results, but linear trend of smoothing April data was significantly increased in most localities. The number of days with dry condition of soil in the past decades has no significant upward or downward trend. However four years (2002, 2003, 2007 and 2009) have been evaluated as dry and two years (2001 and 2006) were evaluated as wet. An amount of extreme spring weather increases.
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