Valentin Kazandjiev
Articles
Agroclimatic conditions in Bulgaria and agricultural adaptation
Europa XXI (2015) vol. 29, pp. 23-42 | 
Full text
doi: https://doi.org/10.7163/Eu21.2015.29.2
Abstract The sole factors of major importance to Bulgaria’s agrarian output are temperature, and water probability. Between these two factors it is the component relating to soil moisture that proves more limiting. Probabilities of occurrence of water and of given temperatures are estimated by reference to summed temperatures and total rainfall, but also in relation to certain more specific indicators. Heat conditions and heat resources can be summed up by reference to the continuity of the vegetation period or growing season, which are limited for each type of plant, with thresholds for each crossed over the spring-autumn period in relation to biological minima. In the case of agricultural crops in Bulgaria, the biological minima are taken to be: 5°C - for wheat, barley, oats, peas, lentils and sunflowers; 10°C for corn, haricot beans and soybeans, and 15°C for cotton, vegetables and other spring cultures. The durations of cold and warm periods are of course interrelated characteristics. In the first period a key further issue is to determine the number of days with snow fall and with snow cover, these being fundamental to the shaping of soil-moisture reserves after the spring snow melt. Defining regions with thermal stress during the vegetation season is a further priority in describing agroclimatic conditions. Values indicative of limitations on crop growth would be one or more periods of at least 10 consecutive days with maximal air temperature over 35°C. Temperatures over 28°C are considered stresses that slow growth, and may even destroy plants if heat stress develops. The components most limiting the growth, development and formation of yields from agricultural crops are conditions as regards moisture represented in relation to atmospheric and soil moisture. The most apparent indicator is the annual total rainfall, or else the rainfall total in periods with average daily temperatures over 5 or over 10°C. A cross correlation matrix between the meteorological elements upon which evapotranspiration depends, i.e. air temperature, relative air humidity, wind speed and vapour pressure deficit, is discussed. One of the ways of assessing the actual necessity for water is to consider the difference between rainfall totals and potential water use, i.e. evapotranspiration. The difference between these two variables presents the balance of atmospheric moisture (BAM). Values for the relationship between real and potential evapotranspiration were calculated for two potential vegetation sub periods: March-June (the period in which the yields from winter crops are shaped) and July-August (the period in which the yields for spring crops are shaped).
Keywords: agroclimatic conditions, agroclimatic resources, zoning of agroclimatic resources
[m.degor@twarda.pan.pl], Institute of Geography and Spatial Organization Polish Academy of Sciences, Twarda 51/55, 00‑818 Warszawa, Poland
[k.blaz@twarda.pan.pl], Institute of Geography and Spatial Organization Polish Academy of Sciences, Twarda 51/55, 00‑818 Warszawa, Poland
Citation
APA: Kazandjiev, V., Degórski, M., Błażejczyk, K., & Georgieva, V. (2015). Agroclimatic conditions in Bulgaria and agricultural adaptation. Europa XXI, 29, 23-42. https://doi.org/10.7163/Eu21.2015.29.2
MLA: Kazandjiev, Valentin, et al. "Agroclimatic conditions in Bulgaria and agricultural adaptation". Europa XXI, vol. 29, 2015, pp. 23-42. https://doi.org/10.7163/Eu21.2015.29.2
Chicago: Kazandjiev, Valentin, Degórski, Marek, Błażejczyk, Krzysztof, and Georgieva, Veska. "Agroclimatic conditions in Bulgaria and agricultural adaptation". Europa XXI 29 (2015): 23-42. https://doi.org/10.7163/Eu21.2015.29.2
Harvard: Kazandjiev, V., Degórski, M., Błażejczyk, K., & Georgieva, V. 2015. "Agroclimatic conditions in Bulgaria and agricultural adaptation". Europa XXI, vol. 29, pp. 23-42. https://doi.org/10.7163/Eu21.2015.29.2
Europa XXI (2015) vol. 29, pp. 43-58 | Full text
doi: https://doi.org/10.7163/Eu21.2015.29.3
Abstract The work described here has sought to determine soil water content change and its relation with the change in the main agro-climate forming meteorological elements for the 1981-2010 period in comparison with the 1951-1980 one. Changes in the main meteorological elements, which lead to spoiled agrometeorological conditions in the second half of the 20th century over the Bulgaria, were identified. These trends are confirmed in the climatic scenarios for future changes through to 2050 and 2070.
Keywords: soil water content, agrometeorological conditions, climate change, winter wheat
[m.degor@twarda.pan.pl], Institute of Geography and Spatial Organization Polish Academy of Sciences, Twarda 51/55, 00‑818 Warszawa, Poland
[k.blaz@twarda.pan.pl], Institute of Geography and Spatial Organization Polish Academy of Sciences, Twarda 51/55, 00‑818 Warszawa, Poland
[mkuchcik@twarda.pan.pl], Institute of Geography and Spatial Organization Polish Academy of Sciences, Twarda 51/55, 00‑818 Warszawa, Poland
[bodego@twarda.pan.pl], Institute of Geography and Spatial Organization Polish Academy of Sciences, Twarda 51/55, 00‑818 Warszawa, Poland
Citation
APA: Georgieva, V., Kazandjiev, V., Degórski, M., Błażejczyk, K., Kuchcik, M., & Degórska, B. (2015). Investigation on soil moisture reserves and meteorological conditions in relation to basic soil types in Bulgaria. Europa XXI, 29, 43-58. https://doi.org/10.7163/Eu21.2015.29.3
MLA: Georgieva, Veska, et al. "Investigation on soil moisture reserves and meteorological conditions in relation to basic soil types in Bulgaria". Europa XXI, vol. 29, 2015, pp. 43-58. https://doi.org/10.7163/Eu21.2015.29.3
Chicago: Georgieva, Veska, Kazandjiev, Valentin, Degórski, Marek, Błażejczyk, Krzysztof, Kuchcik, Magdalena, and Degórska, Bożena. "Investigation on soil moisture reserves and meteorological conditions in relation to basic soil types in Bulgaria". Europa XXI 29 (2015): 43-58. https://doi.org/10.7163/Eu21.2015.29.3
Harvard: Georgieva, V., Kazandjiev, V., Degórski, M., Błażejczyk, K., Kuchcik, M., & Degórska, B. 2015. "Investigation on soil moisture reserves and meteorological conditions in relation to basic soil types in Bulgaria". Europa XXI, vol. 29, pp. 43-58. https://doi.org/10.7163/Eu21.2015.29.3
Assessment of occupational heat stress risk among agriculture workers in Poland and Bulgaria
Europa XXI (2015) vol. 29, pp. 59-72 | Full text
doi: https://doi.org/10.7163/Eu21.2015.29.4
Abstract Agriculture is a sector of the national economy strongly influenced by climatic conditions. A majority of jobs in agriculture are still performed outdoors, under various weather conditions. Several meteorological situations can lead to severe disturbances in the organism of agricultural workers, with high temperature, intensive insolation and elevated air humidity proving especially dangerous, as such weather conditions can lead to overheating and dehydration of the body. The work presented here compares biothermal conditions in Poland and Bulgaria from the point of view of occupational health. To this end, use was made of several indices assessing heat stress in human beings, namely: Wet Bulb Globe Temperature (WBGT), HUMIDEX, Water Loss (SW), Universal Thermal Climate Index (UTCI) and Physiological Subjective Temperature (PST). When account was taken of the occurrence of heat extremes as defined by these indices, it proved possible to distinguish categories of health risk regarded as small, increased or great. Comparison of the two agricultural regions reveals significantly more severe heat stress in Bulgaria than in Poland, in terms of both the frequency of heat-stress episodes and the number of hours (daily and monthly) associated with heat stress. This ensures that dangerous conditions for agriculture workers are primarily present in Bulgaria, rather than in Poland.
Keywords: agriculture, Bulgaria, heat stress, occupational health, Poland
[k.blaz@twarda.pan.pl], Institute of Geography and Spatial Organization Polish Academy of Sciences, Twarda 51/55, 00‑818 Warszawa, Poland
[m.degor@twarda.pan.pl], Institute of Geography and Spatial Organization Polish Academy of Sciences, Twarda 51/55, 00‑818 Warszawa, Poland
Citation
APA: Błażejczyk, K., Kazandjiev, V., Degórski, M., & Dimitrov, P. (2015). Assessment of occupational heat stress risk among agriculture workers in Poland and Bulgaria. Europa XXI, 29, 59-72. https://doi.org/10.7163/Eu21.2015.29.4
MLA: Błażejczyk, Krzysztof, et al. "Assessment of occupational heat stress risk among agriculture workers in Poland and Bulgaria". Europa XXI, vol. 29, 2015, pp. 59-72. https://doi.org/10.7163/Eu21.2015.29.4
Chicago: Błażejczyk, Krzysztof, Kazandjiev, Valentin, Degórski, Marek, and Dimitrov, Peter. "Assessment of occupational heat stress risk among agriculture workers in Poland and Bulgaria". Europa XXI 29 (2015): 59-72. https://doi.org/10.7163/Eu21.2015.29.4
Harvard: Błażejczyk, K., Kazandjiev, V., Degórski, M., & Dimitrov, P. 2015. "Assessment of occupational heat stress risk among agriculture workers in Poland and Bulgaria". Europa XXI, vol. 29, pp. 59-72. https://doi.org/10.7163/Eu21.2015.29.4