FOREST COVER MOSAICS OF CONIFEROUS-DECIDUOUS FORESTS IN THE VALUEVSKY FOREST PARK

Relevance and purpose. The Russian geobotanical science has a profound tradition of studying the vegetation cover heterogeneities. However, the number of studies on the mosaics in complexly organized coniferous-deciduous forests is very limited, and there is high ambiguity in the obtained results. In addition, there has appeared a need to resolve the “terminological issue”. The aim of this study was to assess the vegetation cover mosaics of widespread forest phytocenoses in the Moskva-Oka Plain. Material and methods. We present a review of publications on the intracenotic heterogeneity of forest cover and make an attempt to systematize the existing terminology. The field studies were carried out on the territory of the Valuevsky forest park (Novomoskovsky AO, Moscow) using classical geobotanical methods. The acquired data was analyzed with various modern methods of statistical data analysis. Results and conclusions. The obtained results indicate that differences in vegetation are much more pronounced at the level of phytocenoses than at the level of microgroups. The most powerful edificatory effect of spruce has been confirmed. We identified the following reasons that determine the weak differentiation of vegetation at the level of microgroups: the co-influence of neighboring microgroups, the lack of individual trees’ impact duration for a noticeable transformation of vegetation, and legacies in the structure and species composition of previous states over a long period of time.

TREE LITTER PRODUCTION AND DECOMPOSITION IN FOREST ECOSYSTEMS UNDER BACKGROUND CONDITIONS AND INDUSTRIAL AIR POLLUTION

The paper provides an overview of Russian and foreign articles devoted to the study of the tree litter production and decomposition in forest ecosystems subjected to natural and anthropogenic factors. The spatial variability (below crown and between crown spaces) and the seasonal features of the tree litter production, its chemical composition and decomposition processes are poorly studied. In addition, most of the works, both in native and foreign countries science, highlight the influence of natural factors on the litter production and the processes of its decomposition, while the impact of point sources of industrial air pollution is rarely considered. The study of the variability of the size, fractional and chemical composition and processes of decomposition of tree litter under conditions of industrial air pollution is important for predicting the dynamics of forest ecosystems subjected to the combined action of natural and anthropogenic factors and reducing the negative impact of production processes on forests.

ESTIMATION OF THE YIELD OF WILD BERRIES TAKING INTO ACCOUNT THE LEVEL OF ILLUMINATION OF THE GROUND COVER BY SIMULATION METHODS

Relevance and purpose. Currently known methods of accounting for berry yields are not applicable for multi-species forests of different ages with the presence of undergrowth and undergrowth, widespread in Russia. Difficulties arise due to a set of input parameters, including type of forest growing conditions, breed, age, completeness, but not describing the illumination at the level of the grass-shrub layer, which is the determining factor in the yield of blueberries, cranberries, raspberries. The purpose of this study is to develop an approach to calculating the yield of wild berries, taking into account the illumination at the ground cover level by simulation methods. Material and methods. For the forecast, the FORRUS-S model of forest plantation dynamics is used. The yield data is taken from an existing reference book, which shows productivity in clean plantations without undergrowth and undergrowth. The use of an additional predictor of berry yield, namely, illumination at the level of ground cover, made it possible to predict yields in forests of a more complex structure: multi-species, of different ages, with undergrowth and undergrowth. Results and conclusion. An original approach to calculating the yield of wild berries has been developed. The above approach allows us to estimate the yield of the most common berries in the European part of Russia: blueberries, raspberries, lingonberries. Universal equations have been obtained that make it possible to predict the productivity of berry bushes based on the taxation characteristics of the stand and the illumination calculated in the model.

ACADEMICIAN OF THE RAS ALEXANDER SERGEEVICH ISAEV — 90 YEARS ANNIVERSARY

On October 26, 2021, Academician of the Russian Academy of Sciences Alexander Sergeevich Isaev would have turned 90. A. S. Isaev was doctor of biological sciences, professor, member of the USSR Academy of Sciences, academician of the Russian Academy of Sciences, director of V. N. Sukachev Institute of Forest Siberian Branch of the Russian Academy of Sciences USSR (1977–1988), chairman of USSR State Committee of Forestry (1988–1991), creator and the first director of CEPF RAS (1991–2004), scientific advisor of CEPF RAS (2004–2018), chairman of the Scientific Council of the Russian Academy of Sciences on forests (until 2018), editor-in-chief «Russian Journal of Forest Science» (1980–2018).

SUCCESSION DYNAMICS OF NATIVE SPRUCE FORESTS OF DIFFERENT AGES IN EUROPEAN RUSSIA

Relevance. The article discusses various options for assigning forest biogeocenoses to a certain dynamic position in the successional field of their development. The proposed method for dynamic assessment of the position of forest creates the possibility of assessing the total movement of tree volumes in the age generations of the age range of the forest biogeocenosis the possibility of analyzing the past changes in the age structure of the biogeocenosis and predicting its future development for a very distant future. Material and methods. The objects of research are native virgin spruce biogeocenoses of different ages in the northern taiga of the Kandalaksha forestry enterprise of the Nyamozersky forestry of the Murmansk region, the Severodvinsky forestry enterprise of the Arkhangelsk region; middle taiga spruce forests of the Vepssky forest reserve, Leningrad region. and the tract “Atleka” of the Andomsky forestry of the Vologda region; southern taiga spruce forests of the Kologrivsky forest reserve Kostroma region and the Central Forest Biosphere Reserve in the Tver region. The author studied the features of the structures of the age series of spruce forests, the most typical and productive types of growing conditions for spruce. Results and conclusions. All represented forest communities have different ratios of the number and volume of trees in the age generations of the age series and, as a consequence, different positions in the successional dynamics of development. Wood-destroying fungi of the biotrophic complex, as an endogenous structure of the forest community, actively participates in the dynamic processes of its development at all stages of its successional movement. The infection of trees by fungi of this complex increases from the last generations to the first to the maximum values in the oldest trees of the first generation. The dynamic position of the indigenous virgin forest community of different ages can be described with a wider range of assessments of the dynamics of its development in retrospect and perspective in terms of the ratio of quantitative and volumetric indicators of age generations of age series than in terms of the current structure of the age series. When assessing the successional stage of the forest community, it is necessary to take into account the quantity (volumes) and structure of the deadwood.

REVIEW OF OPEN SOURCE QGIS FORESTRY PLUGINS

Forest industry today has some experience of using Open Source-programs. The article describes the Open Source QGIS plugins to solve the forestry challenges for the forest fire management and forest resources in scientific and applied research. Undertaken analysis will simplify selection of tools for a forest geoinformation project in Desktop and Web versions. A general brief description of modern plugins in QGIS (version 3.18.1) is given, and forestry plugins are characterized. An analysis of external QGIS plugins for working with forest resources and forest fires showed the heterogeneity of research, which has not identified any trends yet. Development of plugins with available data as map services for territories of different spatial coverage may be an option for the future research, while the ability to access archived data is important for the forest industry. The niche of thematic forest tasks in the modern QGIS plugin repository continues to be quite narrow. Transport and environmental applications implemented in GIS tools are more numerous and can solve some tasks of a forest project. Such review of plugins’ functionality should be done on a regular basis, following new developments and new versions of QGIS software.

MATHEMATICAL MODELING OF THE FOREST FIRE IMPACT ON THE BRANCH OF A CONIFEROUS TREE

It is necessary to develop quantitative methods to assess the formation of thermal burns in the morphological parts of coniferous trees. The purpose of the study can be formulated as follows: mathematical modeling of heat transfer in the layered structure of a coniferous tree branch under the influence of a forest fire front. The heat propagation in the “branch-needles-flame zone” system is described by a system of non-stationary differential equations of heat conduction with the corresponding initial and boundary conditions. As an object of research, a digital model of a branch of a coniferous tree for various species, namely, pine, larch and fir, was used. Temperature distributions are obtained for different variants of the branch structure and conditions of the impact of the forest fire front. Conclusions are made about the need for further modernization of the mathematical model. The developed model is the basis for creating software tools for specialized geographic information systems.

Assessment of landscape fires in 2020 in Russia

Landscape fires are one of the main factors of anthropogenic vegetation and soil transformation, as well as anthropogenic climate change. Despite this, until now there have been no detailed estimates of the scale of all types of landscape fires throughout Russia for a full calendar year. This work was aimed at providing such an assessment for landscape fires in 2020, as well as creating a publicly available map of these fires. The fires were mapped by experts and specially trained volunteers on the basis of Sentinel-2 MSI medium spatial resolution satellite images (20 m/pixel) for two periods — from January 1 to May 15, and from May 16 to December 31 inclusive. The total area of identified landscape fires was 25.84 million hectares. The division of the identified fires into presumably controlled (prescribed burning) and uncontrolled (actually fires) was not carried out within the framework of this work. However, the burned areas, corresponding to the area criterion established for single prescribed burnings (up to 10 hectares), account for only 0.96% of the total area of detected fires. The final map of landscape fires, compiled as a result of this work, is available in the public domain at https://maps.greenpeace.org/maps/gpru/fires_2020.

SCALE OF NATURAL FIRE DANGER OF FOREST ECOSYSTEMS OF MELEKHOV I. S. OVERVIEW OF MODERN RUSSIAN METHODOLOGICAL APPROACHES

The article is devoted to the review of various methodological approaches to the estimation of natural fire danger (NFD), as well as to the creation, updation and application of the NFD maps, which are offered by modern Russian scholars. The scale of natural fire danger assessment recommended for use and developed by I. S. Melekhov is presented and analyzed. The methodological drawbacks of this scale as stated by modern researchers are indicated. The paper reviews the development of a new methodological approach to compilation of regional scales for assessing the natural fire danger of forests, by taking into account the links between forest growth conditions as well as seasonal and climatic conditions in the regions of the Russian Federation. The method for mapping of natural fire danger on the basis of maps of plant combustible materials, proposed by the scientific group of the V. N. Sukachev Institute of Forest SB RAS, is studied. We consider studies of the Mytischi Branch of Bauman Moscow State Technical University related to investigation if the possibility for applying mathematical modeling methods for long-term forecasting of changes in NFD under different scenarios of forest management. The method for annual mapping of NFD classes, proposed in the CEPF RAS, is presented. An example of the use of NFD maps in assessing the probability of forest fires in the ICARP FEB RAS is considered. Future research areas are identified, namely, a cartographic representation of the created regional scales of NFD and the results of mathematical modeling of long-term changes in NFD.

WILDFIRES AS A FACTOR OF THE LOSS OF BIODIVERSITY AND FUNCTIONS OF FOREST ECOSYSTEMS

Due to ever-increasing anthropogenic impact and global climate change, wildfires are becoming more frequent and intense all over the world. The wildfire factor is turning into an acute problem for forested countries that requires prompt solutions as the areas of forest ecosystems are reducing catastrophically, which results in an irreparable loss of biodiversity that provides all ecosystem functions and forest services. Many biologists consider wildfires a factor destructive to biota that results in permanent loss of some species and groups of living organisms; even if it is possible for them to recover after a wildfire, they may need a lot of time to do so. However, some studies argue that not only do wildfires reduce the biodiversity in forest ecosystems, but they also increase it, thus contributing to species conservation and sustainable functioning of forests. This article is aimed at analyzing the works that study how wildfires impact the main components, biodiversity, and functions of forest ecosystems. The authors answer the question why wildfires, while being an obvious destruction factor, are sometimes considered a factor for increase in biodiversity. The “positive” influence wildfires have on biodiversity can mostly be reduced to mosaic patterns, that is, forest canopy gaps that occur after a wildfire. However, reference analysis shows that the persistent opinion found in a number of works that a certain frequency of wildfires is necessary to maintain forest communities may be associated with ignored or misunderstood importance of biotic factors in the functioning of forests. In contemporary forest ecosystems, populations of key large mammal species disappeared or are greatly reduced; therefore, there are no microsites they usually form, including large forest canopy leaps (gaps, glades) that provide both opportunities for photophilous flora and pollinating insects to develop and generally sufficient conditions for multi-aged polydominant forest ecosystems with high biodiversity. In the forestry practice, measures are known to maintain mosaics. They include special types of felling, supporting populations of key animal species, etc., and are both significantly less catastrophic in comparison with the wildfire factor and substantiated biologically. The authors provide recommendations for the conservation and maintenance of biodiversity and ecosystem functions in contemporary forests.