Influence of natural factors on the diversity of families of flora in the central part of the Volga basin

The article analyzes the influence of climate and relief features on the number of families of vascular plants growing in the central part of the Volga Basin. For this purpose, 34 local floras were considered on a sample area of 400 km2 each. Regression equations with statistically significant indicators were constructed. These include: the average long-term minimum winter temperature, the minimum temperature in November, the temperature difference in January, and the average slope steepness. For the native fraction, a significant role is played by the following factors: the amount of precipitation in August, the maximum amount of precipitation in April, the maximum illumination of the slopes from the south and the difference in steepness. The equation for adventive families included: the difference in isothermality, the difference in the values of the normalized difference vegetation index, the difference in moisture deficit and the difference in slope steepness. These indicators characterize the heterogeneity of the environment.