Temperature frost-free days

The ecology of weeds deals mainly with the effects of climatic, edaphic, biotic, and abiotic factors in their environment. Climatic factors include light (intensity, quality, and day length), temperature (averages, extremes, and frost-free... 

The rise of the air mean daily temperature above 0°C occurs in the late decade of March over the whole Aral Sea coast. In the north the return of negative temperatures is marked in the first decade of November, in the south in the first decade of December. In spring the rise of the air daily temperature above 5°C occurs everywhere in late March-early April. In autumn this temperature barrier (5°C) is overcome in late September in the northern part of the sea and in the second decade of December on the southern coast. The frost-free period lasts 220 days in the north and 260 days in the south of the Aral Sea coast. 

The agricultural areas of the Tyumen region are characterized by harsh cold winters, relatively short summers, short springs and autunms, a small frost-free period, and sharp changes in temperature during the year and even during the day. 

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