Search Results (4)

The realization of the expected benefits of stubble cover crops (CCs) depends on sufficient plant growth, which is influenced by the sum of effective temperatures (SET) before the onset of winter and the occurrence of the first early autumn frost (FRST). The objective of this study was to calculate the SET for three dates of CC sowing, August 20 (A), September 6 (B), and September 20 (C), from 1961 to 2020, based on daily data from 268 meteorological stations in the Czech Republic (CR). The dates of FRST, when the daily average and minimum temperatures at 2 m and the minimum temperature at the ground level fell below 0 °C, −3, and −5 °C during CC growth, were recorded. The analysis showed a significant trend in the average SET, which increased by 1.60, 0.87, and 0.97 °C per year for scenarios A, B, and C, respectively. As a result, the area where SET conditions allowed for CC flowering from autumn sowing expanded, as visualized in the agroclimatic maps of the country. The average dates of the FRST shifted by 0.05–0.11 days per year over the sixty years, but this was not significant due to high inter-annual variability. The SET was closely related to the average annual temperature and station elevation (r = ǀ0.95ǀ–ǀ0.99ǀ), while the corresponding trend relationships were weaker (r = ǀ0.40ǀ–ǀ0.43ǀ). This study provides data on the zonation of the conditions required to achieve specific CC management objectives. Full article

Climate change brings to the whole world numerous challenges such as an increase in the global temperature, weather fluctuations, periods of drought and heat alternating the local floods. While the majority of the effects are negative for agricultural production, some can be beneficial. Our work presents the evaluation of the changes in the duration of the great vegetation period (delineated with the beginning and end of days with an average temperature T ≥ 5.0 °C) and the vegetation periods of watermelon (Citrullus lanatus Thumb.) and beetroot (Beta vulgaris L.). Data sets on the average monthly air temperatures for the period 1961–2020 from one hundred agroclimatic stations in Slovakia were selected for the estimation of the future average air temperatures using statistical methods (linear trendline). Based on the temperature requirements of the selected crops, the potential maximum duration of the vegetation period was estimated for several decades from 2041 up to 2100. The results clearly showed prolongation of the vegetation periods and changes of their zonation in Slovakia. In 2011–2020, the duration of the beetroot vegetation period in the southernmost part of Slovakia (Danubian Lowland) was 15–20 days longer than in decade 1971–1980. It is expected, that this value will rise by another 10–15 days in decade 2091–2100. Since 1971–1980, watermelon vegetation period duration increased by 5–10 days when compared to decade 2011–2020. It is expected that by 2091–2100, its duration will prolong by another 30–35 days. Full article

Castor bean (Ricinus communis L.) contains ricinoleic acid, making it one of the world’s most important oil-seeds. There are few studies on this species in Chile, despite its potential as an industrial crop. This study evaluated two methodologies (simplistic and presence-species) for determining the aptitude of land for growing castor beans, both of which use climatic information. The simplistic and presence-species methodologies identified 27.89 and 13.19 million ha, respectively. The most important difference between both methodologies was that the mean minimum annual temperature (TNA) was −8.0 °C in the simplistic method, meaning that some areas in the southernmost regions of Chile (Aysén and Magallanes) should be able to grow the plant. Therefore, TNA = 8.0 °C was selected, and the zonation by simplistic methodology was updated. Consequently, both zonations showed similar results, although the presence-species method included northern coastlines, precisely where castor bean has been recorded, while the simplistic method did not. Finally, both methodologies determined the best condition to be central-south Chile, between the Maule and Araucanía regions, even though castor bean presence has only been recorded up to the Maule region. These regions have a huge potential to establish castor beans, but more information about agronomic practices is necessary for its development in Chile. Full article

This research examines the transformation of the agro-climatic conditions of the Altai region as a result of climate change. The climate of the Altai region in Russia is sharply continental and characterized by dry air and significant weather variability, both in individual seasons and years. The current study is determined by the lack of detailed area-related analytical generalizations for the territory of the Altai region over the past 30 years. Most of the published data dealing with an integrated analysis of the agro-climatic conditions in the Altai region date back to the late 1960s and early 1970s; in most cases, this data is from climate reference-books based on the generalized data from the first half of the 20th century. To make accurate forecasts and to efficiently manage agricultural production in the Altai region, area-related data on the state and dynamics of agro-climatic changes have been analysed. The results reveal that in the period between 1964 and 2017, significant climatic changes occurred in the territory of the Altai region. These climatic changes affected the growing season length, which increased due to a shift in the dates of the air temperature transition above 10 °C, to earlier dates in spring and to later dates in autumn. Furthermore, the current study also revealed that the foothills of the Altai Mountains are the most moistened parts of the region and the Kulunda lowland is the most arid part. In the Altai region, the accumulated temperatures and amounts of precipitation during the growing season increased significantly, and the values of integrated coefficients and indices that reflect the moisture supply conditions for the territory also changed significantly. Based upon the results, a schematic map of the current precipitation distribution on the Altai region’s territory has been generated. These results and this map may be used to conduct more detailed studies in the field of agro-climatology and to update the current borders of agro-climatic areas and revision of the agro-climatic zonation scheme. Full article