Home – Home – Jornals – Contemporary Problems of Ecology 2015 number 5

On the basis of the concepts of I. G. Serebryakov (the founder of the science of plant life forms) and the analysis of current data the main directions of research and achievements of Russian botanists in the studying of life forms, as well as prospects for the development of biomorphology were shown. Plants were assessed as a distinctive group of living beings in the context of biological systems integrity. New approaches to habit characteristics, morphogenesis stages in relation to individual variations in ontogenesis, and classifications of plant life forms were considered. The role of systemic and dynamic approaches in description of plant life forms as modular organisms and the role of time as the forth dimension and fundamental category in plant habit formation were discussed. I. G. Serebryakov’s assumption of an evolutionary system of biomorphs as the system of parallel series of life forms similar to homologous series of hereditary variation was confirmed.

Nine species of helophytes were described using the systematic approach: Alisma plantago-aquatica, Butomus umbellatus , Sagittaria sagittifolia, Sparganium emersum, Glyceria maxima, Phragmites australis, Scirpus lacustris, Typha latifolia, T. angustifolia. The species were divided into four groups according to their characteristics: monopodial rosette plants with a short rhizome, sympodial semirosette plants with a short rhizome, sympodial semirosette tuberous plants, sympodial plants with a long rhizhome. It was determined that maternal individuums and vegetative offsprings of polycarpic plants tended to become short-lived. This tendency was implemented in different ways.

On the basis of the study of helophytic and hydrophytic ferns, as well as literature data, adaptive strategies of their sporophytes were identified. A complex anаlysis of the photosynthetic apparatus of the plants was carried out at different levels of its organization : a) fronds, b) mesophyll cells, c) plastid apparatus. Among these species there had been a selection of the plants which were characterized by various biomorphs, active vegetative reproduction and accelerated passing of ontogenetic phases. As the result, the structures promoting aeration, maintenance of optimum water balance and effective photosynthesis had appeared.

The stages of ontomorphogenesis of willows and development of their life forms in different ecological environments were described. The willows belonged to different ecological groups, which structural features served as indicators of habitats. It was shown that the diversity of biomorphs was due to the morphogenesis process with species-specific morphobiological adaptations of shoot systems. At the same time the unique, genetically determined «architectural unit» of genus Salix L., — a triaxial biannual shoot complex, that formed willow’s crown, was retained.

The structure and formation of the crown of Betula pendula Roth. were studied from the perspective of the concept of architectural models and reiteration concept. Some peculiarities in formation and structure of an architectural unit and reiterated complexes due to total, partial, delayed, immediate, traumatic and automatic reiterations were detected. The specifics of these processes under different lighting conditions were identified. The trees crown structure in adverse environmental conditions in cities was studied. It was established that ecological plasticity and ontogenetic polyvariety of B. pendula were mostly determined by reiteration processes.

The shoot systems and ontomorphogenesis of Atragene sibirica L. were studied. Morphological and size polyvariety of all functional types of shoots were described. The high adaptive capacity of the shrub liana in terms of shoot formation in different environmental conditions was established.

Shoot formation and life forms of Thymus baicalensis were studied in different environmental conditions on the Olkhon island. Different life forms were typical for different habitats: in mountain steppes, on a hilltop — vegetatively-immobile aeroxylic dwarf shrubs, on a hillside — vegetatively-immobile prostrate dwarf shrubs, in sandy steppes — cushion-like life forms. The base part of the bush of adult individual forms was formed by the skeletal axis with monopodial and sympodial growth. Morphological adaptation mechanisms in different conditions is to change the structure of the axes, duration of the growth, the nature of rooting and position in space. The mechanism of morphological adaptation to different environmental conditions was expressed by changing the structure of the skeletal axes, duration of their growth, nature of rooting and position in space.

Sixteen species of Hedysarum L. were studied in different eco-phytocenotic conditions in South Siberia. The peculiarities of vegetative reproduction, growth and dying of shoots, morphological structure, life span and modification of aboveground and underground shoots were described. The system of life forms of Hedysarum L. was presented.

The development of Scutellaria supinа individuals was studied in the Asian part of the distribution range. Four life forms (subshrub, dwarf subshrub, taproot herbaceous polycarpic and long-rhizomatous-taproot herbaceous polycarpic) were described in different growing conditions. The mechanisms of structural transformations of individual plants and modes of morphological evolution of life forms of the species were detected.

The study concerned shoot formation and structural and morphological peculiarities of different life forms of Nepeta pamirensis specimens, as well as their morphogenesis and its polyvariety in the conditions of the Pamir Mountains (Tajikistan). Depending on the habitat conditions, Nepeta pamirensis specimens formed three life forms: herbaceous caudex taproot perennial plants, cushion semishrubs and aeroxylic semishrubs. For each life form the phases of morphogenesis were determined and the functional and zonal structure of shoot systems were described.

Structure of monocarpic shoots of some representatives of the Sparganiaceae family (Sparganium emersum Rehm., S. nаtans L. (subgenus Xanthosparganium), Sparganium erectum L. and Sparganium microcarpum (Neum.) Domin (subgenus Melanosparganium)) was analyzed with the help of the modular approach. The structure of all three module categories - elementary (EM), universal (UM) and basic (BM) - was described. With decreasing of EM value, all investigated species lined up in the following descending order: S. emersum (23) > S. erectum (20) > S. nаtans (19) > S. microcarpum (18). It was determined that the level of EM similarity between two bur-reed subgenera reached 30 %. The rest EM part was specific for certain subgenera as well as for certain species. It was shown that dissimilarities between different ecological forms of Sparganium were due not to quantitative EM increase but to their transformation ability which improves species adaptation to varying water level conditions of reservoirs. UM value in the representatives of both subgenera equaled 4, BM values were represented by two similar variants. This was caused by the similarity of habitats of the model species. The plants’ special features on the level of structural-functional organization of different types of monocarpic shoots were shown. Differences in the set of structural-functionаl zones for particular shoot types were also revealed.

The features of growth of C. hirta on the oil-contaminated soil were studied for the first time. Reduction of morphometric parameters of leaves, rhizomes, and enlargement of roots under the influence of oil were determined. Duration of morphogenesis of C. hirta plants on the oil-polluted soil was also reduced. Early ageing of leaves was observed. Rhizomes of the plants from the petropolluted soils branched less. Their plagiotropic growth soon changed to the orthotropic. As the result of the study, the data on morphology, morphogenesis and ecology of C. hirta were replenished.