Санітарний стан соснових насаджень на рекультивованих землях

The purpose of the research is to determine the sanitary state of pine plantations on reclaimed lands, to identify the influence of biotic and abiotic factors on the changes in the sites and to provide recommendations for improving the biological resistance of pine forests in conditions of natural and man-made impact. The sanitary state of pine plantations created on the reclaimed lands of Yurkivskyi brown coal mine has been analyzed. Plants grow in difficult conditions on displaced, low-power soils with carbonaceous sands. The species composition of the lower tiers of forest phytocoenoses (undergrowth, understore, above ground layer), which is formed in medieval artificial pine plantations of fresh pine sites, indicates the restoration of flora diversity of reclaimed lands through forest amelioration. According to data of 61 circular test plots, which cover typical sites of pine plantations on the area of 141.1 hectares, indices of sanitary state of plantations have been calculated. The analysis of the sanitary index has shown that pine plantations are severely weakened. The weakened pine trees make up 44.7 %, and the sanitary index ranges from 3.01 to 3.41. The state of pine plantations of the V age class is approaching the category of plantations that are drying up with the highest value of the state index of 3.41. Weakening of plantations may cause the spread of fires in the fire danger period, outbreaks of diseases and the spread of anthropomorphs. We have revealed that the most influential factors of the significant deterioration of the sanitary state of pine plantations on the reclaimed lands of the Yurkivskyi brown coal basin are dangerous to the root sponge and the drying of trees as a result of a decrease in the nutrition of plants that reached the disturbed maternal horizon at a depth of more than 40-50 cm. In order to prevent the development of the root sponge, it is recommended to create mixed pine plantations with the introduction of up to 50 % of deciduous, which at the same time will serve as a fire barrier for the spread of grass fires. For the improvement of pine plantations, increasing the reclamation efficiency and eliminating the cells of the root sponge, it is expedient to perform continuous sanitary felling with the subsequent planting of deciduous species.Проаналізовано санітарний стан соснових насаджень, створених на рекультивованих землях Юрківського буровугільного кар'єру. Насадження ростуть у складних умовах на переміщених, малопотужних ґрунтах із вуглистими пісками. За даними 61 кругової пробної площі, які охоплюють типові умови зростання соснових культур на площі 141,1 га, обчислено показники санітарного стану насаджень. Аналіз показника санітарного стану показав, що соснові насадження належать до сильно ослаблених. Ослаблені дерева сосни становлять 44,7 %, а показник санітарного стану змінюється у межах 3,01–3,41. Стан соснових насаджень V класу віку наближається до категорії насаджень, що всихають з найвищою величиною показника стану 3,41. Встановлено, що найвпливовішими чинниками істотного погіршення санітарного стану соснових культур на рекультивованих землях Юрківського буровугільного басейну є ураження кореневою губкою і всихання дерев унаслідок зменшення живлення рослин, які досягли порушеного материнського горизонту на глибині понад 40–50 см. Для запобігання розвитку кореневої губки необхідно створювати мішані культури сосни звичайної з введенням до 50 % листяних порід, які водночас будуть протипожежним бар'єром поширення низових пожеж. Для оздоровлення соснових насаджень, підвищення меліоративної ефективності та ліквідації осередків кореневої губки доцільно проводити суцільні санітарні рубки з подальшим висаджуванням листяних порід

Content of the main components of essential oil in the needles of scots pine growing in geographic cultures

The aim of the research is to analyze the content of terpenes in the needles of trees of climatic ecotypes of Scots pine growing in geographic forest crops and to reveal the differences in the level of essential oils. The object of the research is 17 Scots pine climatypes growing in geographical plantations on the territory of the Negorelsk Educational and Experimental Forestry Enterprise of the Minsk region in Belarus. Qualitative and quantitative analysis of Scots pine needles essential oil was carried out by gas-liquid chromatography without preliminary fractionation on chromatograph “Kristall 5000.1”. In the studied climatypes of Scots pine, different levels of essential oil content among monoterpenes, sesquiterpenes and oxygen-containing groups were determined, as well as significant differences in the content of a number of components within the studied groups were revealed. The highest yield of essential oil is observed in the subspecies of the European Western Scots pine – 1.9%, slightly lower than this indicator in the forest-steppe subspecies (1.7%). This indicator was significantly lower in the European Eastern pine variety – 1.1% and the Siberian subspecies – 1.0%. The obtained data on the composition of essential oil and the ratio of a number of components among subspecies and varieties of Scots pine (subspecies: Lapland, Siberian, foreststeppe, European; varieties: European western and eastern) will further select the most promising climatic ecotypes and subspecies for selection resistance to biotic and abiotic environmental factors, taking into account the growth and productivity of stands. Information on the content of essential oil components in the needles of climatypes and subspecies of Scots pine makes it possible to expand knowledge in the field of plant resistance, their safety and growth, especially in the context of the outlined climate chang