Study of physiological and biochemical indicators of pine needles of scots pine (Pinus sylvestris L.) bog and forest populations

Under the impact ofglobal climatic factors and local influence on ecosystems there is a deterioration of common ecological conditions of the biosphere, disturbance of natural circulation and carbon balance and vegetation changing. In connection with this, investigations of adaptation of plant's organisms to environmental changes acquire a great significance. Mire ecosystems perform a complex of important ecological functions in the biosphere. The main components of mire are plants producing biomass, which plays a big role in carbon circulation in the biosphere. Among different ecological factors influencing mire plants, a leading factor under the conditions of abundant congested moistening is oxygen deficiency. Under the conditions of oxygen deficiency, metabolic modes of adaptation of plants are connected, first of all, with process of respiration, which is explained by the specificity of influence. Recompense rearrangements of respiration metabolism reflect, considerably, the use of evolutionary formed glycolysis systems, which transforms into alcohol fermentation, and a pentaphosphate way leading to an increased ATF production, intermediate substances for biological synthesis and biological rehabilitation. A sensitive index of plant physiological condition, which reflects intensity ofphotosynthesis and adaptive reconstruction of metabolism, is the quantity of photosynthetic pigments. . The aim of this work is connected with a comparable investigation of a series of indexes, which characterize major vitally important physiological functions: photosynthesis, respiration and peculiarities of anti-oxygenating system of Scot's pine Pinus sylvestris L. (fam. Pinaceae) in natural ecosystems of mire and pine forest in Tomsk and Bakchar districts of Tomsk oblast. The studied objects grew in natural pine forest biocenosis near villages Pobeda, Bolshoe Protopopovo and Timiryazevo (control): experimental sites were located on the territory of mire ecosystems of eutrophic type -Tagan and oligotrophic type - Polynyanka. Two- year old pine needles were used for investigation. The performed investigations showed that Scot's pine, growing in different ecological conditions, differs by the level of photosynthetic pigments and by peculiarities of respiration exchange. Under the conditions ofpine forest the content ofphotosynthetic pigments is considerably higher, compared with mire ecosystems. Among mire pines there is a lower content of chlorophyll "a " and "b" and carotenoids on oligotrophic bog, compared with euthrophic mire. In pine needles, processes of anaerobic transpiration exchange activate, which promotes a strategy of survival of plants. Different changes of the content of anti-oxidants in pine needles under the conditions of mire and forest ecosystems show specific peculiarities of pine reaction to long-time inundation of the assimilation mechanism ofplants. Participation of substances with anti-oxidant features (catalase, ascorbic acid and carotenoids) creates a strong anti-oxidant pool of substances in above-ground organs of plants; supports correlative connections between the root system and photosynthetic organs, which are necessary for survival of plants under the conditions of oxygen deficiency for the root system.

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