Vitality Analysis as a Constituent of the Population Studies of Natural Reforestation

Abstract

The article focuses on the original approaches to the division of woody plant populations into individual structural groups-cohorts: seedlings, plantlets, small undergrowth, medium undergrowth, large undergrowth, young and generative trees of the tree layer. It is shown that the peculiarities of the natural reforestation process are indicative of the six generalizing models. One of them (Isp-Usml-Tym) corresponds to the renewal, which begins with the formation of seedlings of forest-forming species under the forest canopy that gradually reach the level of forest stand and generative ontogenetic state, gaining the ability to form the next cycle of natural reforestation. The other five (І-Usml-Ty, І-Usml, І-Usm, І-Us, І) characterize the situation where natural reforestation is not cyclical due to the fact that individuals of young generation cease to develop and exist before their transition to a generative ontogenetic state. The expediency of application of the vitality analysis to evaluate cohorts is justified. The authors' approaches to the study of the dynamics of vitality structure of cohorts by the stages of natural reforestation are proposed. The vitality structure of Pinus sylvestris L. cohorts formed in different forest site conditions of Left-Bank Polissia of Ukraine and its change by the stages of natural reforestation are described in detail. It is proved that in various models of natural reforestation the vitality cohort structure acts as a separate and very dynamic characteristic. The change in the characteristic features of the vitality structure by the stages of natural reforestation in P. sylvestris is very diverse. Despite the fact that the P. sylvestris cohorts of different groups of associations vary significantly by vitality parameters, there are clearly defined patterns in change in values of the quality index and vitality Chapter «Biological sciences» structure on simple gradients of the major ecological-coenotic factors. The vitality parameters of P. sylvestris cohorts are a response to the influence of a number of ecological and coenotic factors inherent in a particular habitat. The dynamics of vitality structure is manifested in the wide-scale implementation of its spatial and temporal variability and flexibility. On the territory of the Left-Bank Polissia of Ukraine, Pinus sylvestris is mainly dominated by the models of incomplete natural reforestation.

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“…Common oak (Quercus robur) is one of the main, and often the main forest-forming species in the Ukrainian Polissia. The features of self-healing of oak forests in the Left-Bank Polissia are considered in the study by V. Skliar et al (2019). Self-restoration of oak forests in Polissia is considered by them as a way to restore forest phyto-diversity.…”

The influence of agroforestry on the formation of the structure of forest ecosystems

“…The influence of agroforestry... experts argue that forestry should be identified as part of a large multifunctional system of comprehensive natural resource use and reproduction, requiring the application of a principle of comprehensive research (Skliar et al, 2019). For instance, the position of I.…”

Optimizing Wheat and Barley Yield Through Programming Techniques: Mineral Fertilizers, Plant Protection, and Agricultural Practices in South-Eastern Kazakhstan

“…These methods include the strategic use of protective and stimulating compounds for seed treatment prior to sowing. This approach has been shown to significantly enhance crop health and reduce the accumulation of harmful substances [1][2][3][4][5][6].…”