Soil and geobotanical, typological characteristics of bottomland forest with short-term flooding Poltava-city green belt
Authors: Vlasenko N. O. 
Published: February 2018

Carrying out its assignment Poltava-city green belt bottomland forests with short-term flooding, has significant anthropogenic impact, needs constant research of forest biogeocoenosis present day condition. There have been done the complex research of bottomland forests with short-term flooding which are located in the range of Poltava-city green belt. Forest types according to O. L. Belgard have been noted. Soil and geobotanical characteristics, soil sections macromorphological peculiarities have been given, results of soil water extracts analysis in the investigated forestry have been noted. Throuout the complex researches of all components of forest biogeocoenosis the learning of forest and environment coorelation that is due to anthropogenic effect is topical. Especially it concerns the big cities green belt of industrial regions that suffer from the human direct influence or indirect consequences of his living. Thereby the National special-purpose program «Forests of Ukraine» for 2010–2015 was approved the aim of which is a complex study of this category of forest-steppe zone forest biogeocoenosis. For this reason was made an accent to investigate all-round the Poltava-city green belt forests related to Poltava Region throuout the regional special-purpose program of forestry integrated development «Poltava region forests by 2015». To identify the soil and geobotanical characteristics of biogeocenosis and physical and chemical piculiarities of bottomland forests with short-term flooding adaphotop we will consider the most typical sample plots of different plantations according to its forest stand that grows in relatively identical conditions. Forest areas of Poltava-city green belt belongs to the eastern soil and climatic forest-steppe zone of Poltava Region and is situated in forest-stepp belt of Left bank of Dnipro inside the Dnipro and Donetsk dimple. The most common soils are deep, low humic chernozem and middle clay-loam soil. There are mulch and sandy, agrilloarenaceous soils in river valleys. The picture of exploration area ground structure looks in such a way. The most common ground species of the area is a loess-like clay loam. There are sands observed near the river bed of Vorskla and clay on steep slopes. Soddy-meadow and chernozem-meadow, sandy loam and clay loam soils are involved in the bottomland forests formation. Typical chernozem occupies significant territories, which is formed by herbaceous grouping of mesoxerophytes, euxerophytes and xeromesophytes. Floodplain soils are divided into three parts: riverine, central and terrace near flood plain. In the riverine part is formed the most light mechanical components of interbedding soils formed on new derived silt from slightly humic layers. There are a low percent of humus (not more than 1 %) and nutritional chemicals. Thereby their fertility is low. In the central part of floodplain had been formed the sandy loam and clay loam soils with stronger profile on the massive, often calcareous or carbonaceous parent rock material. In cases of flood the water is widely overflowed and stay for a long time rich in sludge particles. It is the richest soils of the floodplain. The done research gave us the opportunity to clear up that the bottomland forests with short-term flooding of Poltava-city green belt are consist mainly of oak, aspen and alder forests. The formation and distribution of the main associations of floodplain forests depend on the regime of floodplain, trophotop and relief inhomogenuity. It was noticed that it can be found three more typical natural forest vegetations related to bottomland forests with short-term flooding inside the Poltava-city green belt: Dc' 3 (moist linden oak forest with hairlike sedge), Dn / 4 (alder forest with muddy tall herbaceous vegetation), Dc / 2 (live aspen forest with). It was noticed, that in all investigated plant formations the forest site type is sandy loam with different variations: live (SP / 2), moist (SP / 3), muddy (SP / 4). Different variations of soil has been investigated. There is no carbonate in soils of the investigated biogeocenosis. Water extract analysis tell about the lack of salinity properties, dry particles ranges (0,05–0,2 %), pH is alkaline. Detailed soil and geobotanical characteristics and establishing peculiarities of bottomland forests with short-term flooding adaphotop will give opportunity to reconstruct the existing Poltava-city green belt plantations and organize the stationary investigations with the aim of their more rational employment and saving.