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Studying four species of red wood ants (Formica rufa, F. polyctena, F. aquilonia, F. lugubris), we examined nest morphometrics (height and diameter of anthills), spatial parameters (location of anthills of different sizes relative to each other), and the number of trails per colony in three regions of Ukraine and Russia: Kyiv region (877 anthills), the Urals (274 anthills) and Cis-Baikal (72 anthills). We have established a relationship between the number of anthills in the nest complex and the maximum parameters of the average height and diameter, as well as the average number of trails. Under optimal conditions, the infrastructure of the forage area of red wood ants becomes more complex - an increase in the average number of trails. We have shown that the morphometric parameters of anthills differ significantly in four species of red wood ants. In addition, it was confirmed that single anthills are on average smaller than colonial ones and have, on average, fewer trails per anthill. There is a pronounced spatial aggregation between the anthills of red wood ants of the same species (F. rufa, F. polyctena, Kyiv population) of all size classes. [ABSTRACT FROM AUTHOR]

Red wood ants are capable of active thermoregulation in the nest, which allows them to achieve a high number of workers and a dominant position in biocenoses. We investigated the features of the spring warm-up and the ability for active thermoregulation of the mounds of the ants Formica polyctena and F. rufa in the vicinity of Kyiv, Ukraine. We have proposed a model of thermoregulation of the mound, which takes into account the heat flow from the sun, heat exchange with air and soil, and endogenous heat generated by the antcolony. The calculation of the model for specific values showed that only F. polyctena mounds with a diameter of more than 0.9 m and F. rufa mounds with a diameter of more than 1.1 m are able to maintain a constant optimum temperature in the nest. Comparison of the calculated data with the measurement results onthe studied nests showed that the diameters of the majority of moundsexceededthe critical values for both speciesindicatingthe ability ofthermoregulation. The possibility of using the model to study the thermoregulation of moundsin different natural areas is discussed. [ABSTRACT FROM AUTHOR]

This article describes an investigation into the seasonal variations of frequency, damping ratio and amplitude of swaying and vibration of Norway maple Acer platanoides L. The study was carried through a series of pull and release experiments in situ and on branches in the laboratory using an artificial air flow. It was found that foliated trees had a natural sway frequency that was on average 1.6±0.2 times greater than in the out-of-leaf state. In contrast, the damping ratio of maple increased by 1.5±0.3 times in the summer period. The stem swaying initiated vibrations, i.e. elastic wave, in the roots with frequencies in the range of 45-50 Hz. Laboratory tests showed that the vibration amplitude of branches depended linearly on leaf mass for an air flow velocity of 1.94 m/s. [ABSTRACT FROM AUTHOR]