Rozsoshentsy forest area of Poltava-city green belt (soil-geobotanical and typological and characteristic)

Abstract

Natural forests have their own ancient history, for this reason, their composition and structure reflect their existing conditions. In the artificial forests, only growth class and plantations general conditions can be in part the indicator of this residence. O. L. Belgard investigated natural biogeocoenosis and artificial cultural geocoenosis and worked up the detailed forest typology. The peculiarity of O. L. Belgard typology is biogeocoenological approach to the understanding and forest investigating based on G. M. Vysotskiy, G. F. Morozov, V. M. Suchkov ideas.  O. L. Belgard accepted the conception of forest biogeocoenosis the components of which are phytocoenosis, zoocoenosis, microbiota, climatope and adaphotope. Rozsoshentsy forestry consists of 87 planning compartments with a total area of 3130.0 hectares, is a part of National Enterprise “Poltava forestry” and is situated on its southern part on the territory of Poltava administrative district and Poltava city. There are no publications in the science literature that could systematically reflect the results of investigations taken place in Rozsoshentsy forest area.  Different scientists in different times investigated particular types of vegetations; the general characteristic of forests was specified in some works. The aim of our work is the forest typology investigation, ecological and biological, typological, soil and geobotanical peculiarities of natural and artificial forests of Rozsoshentsy forest area. For the fist time the investigation of natural and artificial forests of Rozsoshentsy forest area of Poltava-city green belt has been started according to the method of O. L. Belgard forest typology. Groups that were investigated inside the forestry are related to hydrotopes of bottomland forests with long-term flooding, bottomland forests with short-term flooding, noninundated with arena and ravine forests.  The forest type is defined by accessories to specific trophotope and hydrotope and connected with floodplain factor of certain place of existence. The main place in definition of ecotope peculiarities takes vegetations that fully reflect the dimensionality of conditions. There are some plant associations inside the forest type that give an idea about coenosis from the floristic point of view.  One or several associations can correspond to each forest type with direct species structure of tree, bushy and herbaceous layers. Artificial forests typological characteristic based on three taxonomic rank units: forest growth conditions type, ecological structure type and forest stand type. It was found out that the main forest types in structure of investigated forest area are oak, pine, sticky alder and aspen, poplar and birch forests. It means that main forest forming types are six types of wood.  Rozsoshentsy forest area of Poltava-city green belt dendroflora has 33 tree and bushy types, 24 genuses, 14 families, 2 rooms. The most popular forest types on the investigated territory according to the forest typology are new oak and pine trees – 31.9 % , new pine forests – 9.1 %, new and dry maple and linden forests – 27.2 % and 6.3 % correspondently. Forest accounts for 5.3 % of forested areas with excessive wet ground. The investigation that was carried out gave us an opportunity to find out four natural forest vegetation types: (new linden and hornbeam forest with wide grasses), Dn4 (alder forest with moist tall grasses), Dc3 (wet aspen forest with aise-weed), De3 (wet white poplar forest); and two types of artificial forest vegetations: De3 (wet white poplar forest) and AB1 (birch forest with dryish miscellaneous). Different variations of soils have been investigated. It was found out that in investigated natural phytocoenosis the type of forest growth conditions is clay loam with different variations: new (СГ2), wet (СГ3),  moist (СГ4); and wet sandy loam (СП3); in artificial cultural phytocoenosis the sandy loam is wet and dryish. The prevailing soil types on the territory of Rozsoshentsy forestry are dark grey podzolized forest loam, typical chernozem and podzolized hard loamy chernoozem, but in floodplain of the river Vorskla  is a peat-bog soils. The content of humus is 7–8 %. The depth of ground water deposits connected with deposits of brown-red underclay (impermeable horizon) and ranges according to the relief elements and soil degree of erosion from 15 to 34 m. Carbonates are absent in soil of Rozsoshentsy forest area. Water extract analysis tells about the lack of salinity, dry particles ranges between 0.05–0.2 %, PH is mostly alkaline. Detailed ecological and biological characteristics and establishing peculiarities of Rozsoshentsy forest area adaphotope will give an opportunity to reconstruct the existing Poltava-city green belt plantations and organize the stationary investigations with the aim of their employment and saving.