The rapid and accurate estimation of aboveground forest phytomass remains a challenging research task. In general, methods for estimating phytomass fall mainly into the category of field measurements performed by ground-based methods, but approaches based on remote sensing and ecological modelling have been increasingly applied. The aim is to develop the scientific and methodological framework for the remote sensing estimation of qualitative and quantitative characteristics of forest stands, using the combination of surveys and machine learning models to determine phytomass of forest stands and calculate the carbon balance. Even-aged stands of different tree species growing in the forest steppe zone of the East European Plain were chosen as test objects. We have applied the modernized methodological approaches to compare and integrate forest and tree stand characteristics obtained by ground-based and UAV-based comprehensive surveys; additionally, we developed computer vision models and methods for determining the same characteristics by remote sensing methods. The key advantage of the proposed methodology for remote monitoring and carbon balance control over existing analogues is the minimization of the amount of groundwork and, consequently, the reduction inlabor costs without loss of information quality. Reliable data on phytomass volumes will allow for operational control of the forest carbon storage, which is essential for decision-making processes. This is important for the environmental monitoring of forests and green spaces of various economic categories. The proposed methodology is necessary for the monitoring and control of ecological–climatic and anthropogenic–technogenic transformations in various landscapes. The development is useful for organizing the management of ecosystems, environmental protection, and managing the recreational and economic resources of landscapes with natural forests and forest plantations.

Vast forest areas are spreaded in Russia and perform environment-forming, nature-protective and climate-regulating functions, including carbon sequestration. At the same time, increasing of destructive forest fires scale in recent decades has led to depletion of forest resources. To combat forest fires, it is necessary to develop preventive measures to reduce the number and severity of forest fires and establish reliable evaluation criteria for fire hazard assessment in forestry. However, indices of fire hazard assessment that exist in Russia are not always allowed to determine the degree of fire hazard reliably. The studies were performed in pine forests on the territory of the Central Forest-Steppe. The key forestry factors influencing the fire hazard situation in pine stands are identified: the presence and amount of combustible materials, the state of the stand, as well as the age structure of tree stand. According to burning indices, the highest fire hazard was common for young and middle-aged pine stands, while for ripening, mature and old-growth forests, fire hazard increasing was not observed. A set of parameters that characterize soil moisture and ground cover peculiarities have also a significant impact. Forest growth conditions were shown to be an important indicator for assessment of fire hazard class. Identified factors that have a key impact on the fire hazard in forests will make it possible to improve methodological approach for monitoring and preservation of forests.

Taking into account the high value of nuts of the genus Juglans, the increase in their production should go not only through the selection and breeding of the best varieties and forms, but also by shifting the existing border of cultivation to the north, into "new" regions, where nut-bearing crops are not yet widespread. For full adaptation, all components of plant resistance should be at a high level. In this regard, the main purpose of the work is to study and analyze the adaptive features of plants. Were studied local forms of the walnut, nut the manchurian, nut the black, nut the gray and nut the heartshaped. In determining the resistance of plants according on the main adaptive attributes, generally accepted methods based on artificial modeling of unfavorable conditions were used. An integrated approach to the determination of the stability of forms and species of nuts is proposed, which consists of an integrated assessment of the main components of plants, which has an advantage over the conventional field method of evaluation, since a reliable determination of stability in the field requires a long observation (sometimes several years). On the basis of indicators of comprehensive of the sustainability, a scale for the optimal use of forms and species of nuts of the genus Juglans in the Voronezh region was compiled.

Taking into account the emerging trend towards temperature increase in the region of the research in recent years, introduction and cultivation of the genus Juglans in the Voronezh region is a pressing issue. The paper reviews 4 species of nuts – black walnut, Manchurian, gray and heartnut, which are the most promising for the creation of forest crops, because they are the most resistant to adverse factors in the area of introduction among all species of the genus Juglans. Taking into account the specific features and the intense form diversity of nuts of the genus Juglans, an assessment scale was proposed and a regional methodology was developed for assessing the quality of fruits. The quality of the fruits of the forms and types of nuts was determined by the total value of the evaluation criteria, taking into account the level of significance of each trait. The trees species which in aggregate have the best resistance to adverse factors and have acceptable quality fruits (EC = 136 and 188) are black walnut and heartnut. It is these types of the genus Juglans that are primarily recommended for full reforestation and afforestation in the Voronezh region.

Taking into account the emerging trend towards temperature increase in the region of the research in recent years, introduction and cultivation of genus Juglans in the Voronezh region is a pressing issue. The studied the dynamics of phenological phases 5 the most promising for the cultivating species of nuts (Juglans regia L., Juglans manshurica Max., Juglans nigra L., Juglans cinerea L. and Juglans cordiformis Max.), which are the most promising for the cultivating. Has been identified a significant increase in air temperature over the past 30 years. A close correlation between the temperature indicators and the dynamics of phenological phases is established (primarily occurring in the spring). With an increase in average annual air temperature by 1 °C and remaining unchanged humidity indicators, the duration of the growing season increases by an average of 4 days. Keeping in mind the emerging tendency of climate change, the cultivation of heat-loving southern forms of Juglans nuts in the Voronezh region will constantly increase.

The development of Earth remote sensing methods, neural network technologies, creation of machine learning models, etc. will allow developing new algorithms, indicators and criteria that will significantly increase the efficiency of forest monitoring and help reduce financial costs. The basis for the work was the verification of ultra-high- and high-resolution satellite imagery data based on in-situ survey materials conducted on permanent test plots in the Voronezh region. The generated elements of training samples using a neural network classifier allow for automated, highly accu-rate determination of forest stand taxation indicators based on remote sensing data. When verifying the amount of aboveground phytomass calculated based on remote sensing data and in-situ survey materials, significant similarity of the presented results was revealed. In 67% of cases, the average phytomass values determined by different methods did not differ significantly from each other (at a significance level of p<0.05). Reliable differences were found in decid-uous stands with high horizontal canopy density, the presence of a second tier and abundant understory vegetation. As a result of the work, a theoretical basis was laid for further research in conducting remote monitoring in the field of for-est conservation, protection and reproduction. The material of the work is useful in building multidisciplinary practical work in the areas of restoration of biological diversity of phytocenoses, as well as ensuring the integrity and ecological stability of forests, under modern trends in carbon cycles and climate changes.