Relationship between hydrothermal coefficient (HTC) and productivity of pastures in the arid zone of Northwestern Caspian Sea

In the arid zone, one of the ways to provide animals with feed is the organization of forested pastures, the productivity of which largely depends on weather conditions. Our study analyzes changes in meteorological conditions and hydrothermal coefficient (HTC) during the growing season April-October from 2018 to 2022 and their impact, on natural and forest-reclaimed pastures of the sandy Bazhigan massif of Northwestern Caspian Sea. Pasture productively was negatively correlated with the temperature and positively correlated with the precipitation. The relationship between hydrothermal coefficient (HTC) and productivity of different types of pastures has been established with coefficient of determination of R2 of 0.765 under pasture with different density and R2 of 0.879 under natural pasture. Results showed that the atmospheric humidification is the determining factor of stable pasture productivity in the conditions of climate change in the arid zone of Russia.