On three markers of permanent ring growth variation of Scots pine in marsh and upland dendrocenoses

The regularities of variability differentiated by the signs of growth in width of more than 210,000 tree rings from1333 specimens of the Scots pine in seven typical dendrocenoses of hydromorphic and automorphic development on the rivers Ob andTom are described. It is shown that regardless of the typological age and status of a pine, the common feature of prepared chronologiesis their coordinated order in length and wave amplitude in the range of 7-11-13-17-year climate conditioned cycles. Within thesewaves, age frequency of smaller amplitude and duration appear with biological and ecological nature of the topology. It is consideredthat hydromorphic complexes, being self-regulating natural formations and due to their common conservativeness, have an evidentability to weaken or even suppress the impact of the parameters of the environment, and marsh forest stands against the latter are notsufficiently sensitive. The total dynamics of these properties reflect a weak variation width of tree rings and their small dimensions.Therefore, in this study to decipher the real reactivity of marsh stands the method of sequential accumulation of data on the leading signsof response was used. It allowed to get both theoretically and practically interesting series of prepared chronologies of radial growth forthe south-taiga subzone of Western Siberia and on their basis develop a vision of the structure of the hydromorphic and automorphicforest stands reaction to the current variability of the integrated complex of environmental factors. As an example, we give a fewrandom samples from these chronologies for the typical pine forest with a mixed-age stand structure. The study was based onsufficiently large samples, representing every second or third random tree depending on the structure of the tree layer. The graphiccomparison of the actual and smoothed data showed that the state of the wetland stands of Western Siberia is characterized bycontrasting cyclical swings in relative share of trees with the radial growth positive and negative signs separately. Naturally, they arecontrasted to each other, but synchronized in the time of occurrence and duration. Moreover, their reflectivity is shown only to theextent that it may be influenced by the proportion of trees with the zero sign of growth. The cycles contain years-markers, when theproportion of trees with positive or negative effect of the reaction reaches the maximum of 84-87% and the minimum of 4-8%depending on the current combination of climatic factors and environmental confinement of plants. Representation of the neutral form ofthe response in the swamp forest stands did not exceed 30-32%. For specific forest types, it is practically stable although in general ittends to increase from eutrophic (2-18%) to oligotrophic (12-32%) conditions of growth.

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