Scientific publications

In 2024, the Northern Water Problems Institute of the Karelian Research Centre of the Russian Academy of Sciences began limnological studies on a small drainless dystrophic water body (in the Kivach Nature Reserve, Karelia) within the framework of the Key Innovative Project of National Importance “Unified National System for Monitoring Climate-Active Substances” to develop a system for monitoring carbon pools and greenhouse gas fluxes in boreal aquatic ecosystems (water bodies, watercourses) of North European Russia. In such lakes, the bottom is covered with Bryidae mosses, which can make a significant contribution to the carbon cycle. Therefore, studies of photosynthesis and respiration of the dominant moss species Warnstrofia fluitans (Hedw.) Loeske from a model water body were carried out. The methodological approach was based on estimating the rates of photosynthesis and respiration of the moss using the Winkler method relying on the principle of light (photosynthesis) and dark (respiration) flasks in a laboratory experiment. The change in the oxygen concentration in flasks with green shoots of W. fluitans versus the initial concentration was estimated after 24-hour incubation. The flasks were incubated in a climate chamber at the temperature, illumination, and daylight hours that corresponded to the conditions on the moss mat surface in the studied water body. The specific rate of photosynthesis (0.052), specific rate of respiration (0.02) and growth efficiency (0.032) of photosynthetically active (green) moss were calculated. Based on these indices and the wet weight of photosynthetically active moss from 1 m2 area from the upper layer of the moss mat, we derived the summer daily values of gross photosynthesis (211 mg C), net production (81 mg C) and respiration (130 mg C) of W. fluitans. Previously, the Winkler method was used to determine the photosynthesis and respiration of aquatic bryophytes in situ, which is a very complex and laborious process. The results of the present study are in good agreement with published data on the net production and respiration of mosses in high-latitude lakes obtained by other methods, demonstrating the feasibility of running such measurements in vitro.