Bioecological characteristics of sea buckthorn (Hippophae rhamnoides L.) in different habitats of Lori Province, Armenia

Sea buckthorn is an important shrub species in Armenia. It is a drought-resistant shrub adapted to dry conditions. It strengthens steep, eroded slopes due to the active growth of its root suckers. The aim of the study was to identify bioecological features of sea buckthorn plants ( Hippophae rhamnoides L.) in different habitats of the Lori Province of Armenia. Sea buckthorn habitats were studied in the Spitak and Gugark districts of Lori Province under varying environmental conditions. In the Gugark district, studies were conducted near the village of Margahovit. The study examined several physiological processes in sea buckthorn plants, including: water regime (content of total, free and bound water); water deficit; gas exchange (O 2 absorption and CO 2 emission rates); biometric indicators of fruits; and sucrose content. The ecological and physiological characteristics of plants were determined using generally accepted methods of field and laboratory research. The conducted research allowed us to draw a number of conclusions. The raw weight of the samples taken from the two study areas was the same, but the total water content was 16% higher in the leaves of plants from the more humid area near Spitak. Comparing the plant samples from the two areas, it can be emphasized that the amount of O 2 in plant samples from Margahovit was 0.2% less, while in samples from Spitak it was 0.04% less. These data show that the intensity of O 2 use is high in Margaovit plants. The amount of CO 2 released by Margaovit plants increased by 3 ppm, and by 12.5 ppm in Spitak samples. Therefore, Margaovit plants exhibit a lower net release of CO 2 during respiration during photosynthesis compared to Spitak plants.