THE PROBLEM OF REFORESTATION OF WOODY VEGETATION OF MOUNTAIN RANGES OF KON CHU RANG NATURE RESERVE (VIETNAM)

Background. The article presents materials on the study of the main tree species especially valuable for reforestation in the Kon Chu Rang nature reserve (Vietnam). It has been established that the diversity, as well as the physico-chemical and granulometric composition of the soil cover of the mountain range are due to the diversity of rocks in connection with the geological structures to which they are confined (the Pleiku plateau is located on basalt shales). It was revealed that the climatic conditions of the Kon Chu Rang nature reserve are characterized by high humidity and an abundance of precipitation throughout the year, which is why, due to the high washing regime, the soils are depleted of elements valuable for the growth and development of tree species. Most of the species grown in the nurseries of Vietnam are introduced, in this regard, the cultivation of seedlings and seedlings of valuable species for reforestation with a closed root system and an established irrigation regime, herbicides and fertilizers is required.  Purpose. To study the possibility of reproduction of native forest tree species in the conditions of the mountain plateau of Central Vietnam. Materials and methods. The object of research was the climatic conditions of Vietnam, the soils of various relief elements of the Kon Chu Rang nature reserve, rare and especially valuable tree species: Dacridyum elatum Roxb. Wall. ex Hook., Michelia tonkinensis A. Chev., Dialium cochinchinense Pierre, Dipterocarpus kerrii King., Dacrycarpus imbricatus de Laub., as well as methods of their accelerated reproduction for reforestation. In order to determine the physico-mechanical and physico-chemical, chemical, agrochemical and biological properties of soils on the territory of the Kon Chu Rang nature reserve, soil samples were taken to a depth of 120 cm in increments of 10 cm on various elements of the mountain relief: on a shrub meadow site, in a forest with native tree species, on a pilot site of a hospital in the area of the reserve reserved for a forest nursery. When solving the tasks, methods of field experiment, expedition research were used, with the help of the Garmin device, the coordinates of the seed and seedling collection points were determined and fixed in order to build a route survey map. Seasonal development of trees was studied on the basis of field and research. The height of seedlings was measured at the beginning and end of the study period. Every plant in the collection was measured. The reproductive ability of species was studied by quantitative and qualitative characteristics of fruiting. In laboratory analyses were used the Kapel’ – 105M, capillary electrophoresis system, laboratory scales TO VK-600, analytical scales VL-220C, spectrophotometer PE-5400 UV. Mathematical processing of the results is carried out in the MS Exel and Statistica application programs using small arrays of observational data that were combined into homogeneous clusters. Results. The article contains data from studies of mountain forest territories, relief and soils of the Kon Chu Rang nature reserve (Vietnam), the main results of which are aimed at preserving and reproducing indigenous especially valuable tree species exposed to anthropogenic impact. It has been determined that many introduced species of 12 nurseries in Vietnam are extremely difficult to reproduce in mountainous terrain due to their morphological and biological characteristics, as a result of which they cannot be used for reforestation. It was revealed that the soil cover of the Kon Chu Rang nature reserve is characterized by variegation, distribution of areas, granulometric composition and humus content. Due to the large amount of precipitation, the soils are depleted of the necessary composition of elements necessary for good growth and development of woody species. It is determined that for the successful cultivation of especially valuable tree species in the nursery, surface watering and constant maintenance of soil moisture, treatment with herbicides and fertilizers are necessary. Seedlings are recommended to be grown in containers with a closed root system. Conclusions. Based on the data obtained as a result of studying the soil and climatic conditions of the Kon Chu Rang nature reserve (Vietnam), as well as the results of creating an experimental nursery of seed material for reforestation, it can be concluded that with the correct selection of irrigation standards, herbicides and fertilizers, it is possible to obtain a standard yield of standard planting material from a unit to ensure a high survival rate of seedlings and seedlings, as well as their subsequent growth, which will solve the urgent problems of improving the species composition of the indigenous forests of the Vietnam. Sponsorship information. The work was carried out within the framework of the topic E-1.6 "Development of technology for growing seedlings of the main native trees species of indigenous forests in Vietnam as the basis for solving the fundamental scientific problem of tropical forest restoration." Joint Vietnam-Russian Tropical Science and Technology Research Center.