Cedroxylon shakhtnaense (Blokhina 2010) Dolezych, Mantzouka et L.Kunzmann comb. nov.; A fossil Abies wood from the late early Miocene Mastixioideae flora of Wiesa (east Germany)

We describe the first evidence of fossil Abies wood from the late early Miocene fossil plant assemblage of Wiesa in east Germany. The comparatively well-preserved piece of xylitic wood was recovered in the kaolin quarry at Hasenberg hill in Wiesa. The Wiesa assemblage is characterized as being allochthonous and partly parautochthonous mass deposits of diaspores, leaves, and wood. The latter component is rather incompletely studied so far. The described fossil is characterized by high rays, mostly uniseriate bordered pits, generally thick and pitted horizontal and tangential ray cell walls, but also partly smooth horizontal ray cell walls, absence of ray tracheids, the occurrence of traumatic resin canals, and rare occurrence of axial parenchyma of two types. This type of fossil wood has been described as Abietoxylon shakhtnaense Blokhina from the Oligo-Miocene of Sakhalin, Russia. Due to nomenclatural issues of Abietoxylon a recombination to Cedroxylon Kraus emend. Gothan is proposed following common practice for affiliation of abietoid fossil wood of Cenozoic age. Cedroxylon shakhtnaense comb. nov. shares anatomical characteristics with the wood of extant Abies Mill., in particular with sections Abies and Grandis, and is most closely related to section Grandis. The properly preserved fossil wood from Wiesa provides the opportunity of applying qualitative and quantitative analyses for testing and discussing its placement in relationship to intra-tree variability and ontogenetic aspects. The first evidence of fossil wood of Abies from Wiesa confirms again the presence of the genus in mid-latitude subtropical zonal vegetation during the beginning of the Miocene Climatic Optimum.

New data on vegetation of two localities in the southern part of the typical tundra subzone in the Gydan Peninsula

The syntaxonomic diversity of vegetation of two localities in the southern part of the typical tundra subzone in the Gydansky Peninsula includes seven associations, three subassociations and eight variants. New associations (Tanaceto bipinnati–Salicetum polaris Khitun ass. nov. hoc loco, Calliergono cordifolii–Salicetum lanatae Khitun ass. nov. hoc loco), subassociations (Hierochloo alpinae–Hylocomietum splendentis asahinetosumchrysantae Khitun subass. nov. hoc loco, Carici rariflorae–Sphagnetum baltici sphagnetosum steerei Khitun subass. nov. hoc loco) and eight variants are described in this region for the first time. Although in the northern part of the typical tundra subzone they occupy zonal positions, dwarf shrub communities with abundant herbs (Luzula tundricolae–Hylocomietum splendentis Telyatnikov et al. 2019) were not found in the studied locations. Tussock tundra (Sphagno–Eriophoretum vaginati typicum) occupies flat or gently sloping hills, and we consider it as the predominant zonal vegetation. The position of the boundary between the southern and the typical tundra subzones is corrected. According to our observations, it lies further north (up to 100 km on the eastern part of the peninsula) than it was shown on previous zoning schemes. Comparison of the syntaxonomic diversity in the southern and northern parts of the typical tundra showed little similarity, only two associations are common (Hierochloo alpinae–Hylocomietum splendentis Telyatnikov et al. 2019 and Tripleurospermo hookerii–Poetum alpigenae Czerosov, Sleptsova et Mironova 2005). We explain this by differences in local lithology: loams were predominant in the northern part and sands dominated in the southern part.

Evaluation of the disturbed lands recultivation projects in the Republic of the Crimea

The development of the extractive industry on the territory of the Crimean Peninsula leads to an increase in the number of quarries and, consequently, to an increase in the area occupied by disturbed lands requiring recultivation. The reclamation of such land plots on the basis of creating the necessary conditions for the development on them of regenerative successions of zonal vegetation and ultimately the formation of soils is much cheaper for land users. Therefore, studies of the rates of soil formation, including using the methods of mathematical modeling of the processes of formation of the humus horizon of the soil over time, become relevant. Based on the example of the Alexandrovsky field of saw limestone in the Black Sea region of the Republic of the Crimea, the economic efficiency of reclamation of disturbed land was calculated. The results of the calculation showed that in terms of cost-effectiveness, it is more rational to use the mining engineering model with further self-overgrowing of the sites to be reclaimed when it comes to reclaiming disturbed lands of the Alexandrovsky career.

THE CREATION OF BIOCLIMATIC VEGETATION MAP TO DEVELOP SUSTAINABLE AGRO FORESTRY IN BA AND KONE RIVER BASIN, VIETNAM

Bioclimate and natural vegetation have a long - term relationship that identify the potential vegetation distribution at different areas. For that reason, bioclimatic classification system was applied to the territory of Ba and Kone river basin, Vietnam. The precipitation and temperature dataset of Ba and Kone river basin was collected from 17 climate, hydrology, rain gauge stations which allowed to create a bioclimatic map at a scale of 1:250.000. Three bioclimatic factors of thermal-moisture basic conditions such as annual temperature (TN), annual rainfall (RN), length of dry season (n) are selected as criteria system of Ba and Kone river basin’s bioclimate. In order to describe the relationships between bioclimatic variables and zonal vegetation units, the resulting map presented 12 bioclimatic units corresponding distribution of vegetation from low to high altitudes. By building bioclimatology map in Ba and Kone river basin, the government can develop sustainable agro forestry in Central Highlands and South Central Coast of Vietnam.

Impact of natural fires on the vegetation cover of steppe and forest-steppe zones (European part of Russia, Middle Volga region)

The effect of natural fires on the vegetation cover of steppe and forest-steppe zones in the south-east of European Russia (the middle course of the Volga River) has been evaluated. The research used methods of studying biosystems at organism, species, population and cenotic levels. The study revealed the possibility of regrowth of aboveground plant parts after fires, changes in the population structure of species, and resistance of populations and zonal plant communities to the effects of natural fires. The most vulnerable among zonal vegetation types are pine forests, feather-grass and petrophytic steppes. Frequency, intensity and area of natural fires in the Middle Volga region cause significant changes in the structure of vegetation cover and reduction of biodiversity. The results obtained in the study of the impact of fires on vegetation can be used in the planning and implementation of environmental and reforestation measures.

Spatial vegetation distribution and zonal vegetation type on islands in southern part of the Lena Delta (Eastern Siberia)

In this research spatial distribution of the different vegetation types on Lena Delta islands described in connection with their relief, time of formation and geological substrates. It was shown that zonal vegetation can be find only on third river terrace on gentle slopes. Because of continuous permafrost predominant vegetation is presented by hydro serial communities united into successional cycles. Zonal vegetation types occupy not more than 1-2% of the whole area.

ЛІСІВНИЧО-ТАКСАЦІЙНІ ОСОБЛИВОСТІ ГРАБНЯКІВ ПРИРОДНОГО ЗАПОВІДНИКА «МЕДОБОРИ»

In the Nature Reserve of Medobory a zonal vegetation is represented by dark deciduous forests, with a hornbeam and oak trees mainly, dominated by Quercus robur, Caprius betulus, and Flaxinus excelsior. Within the tree stands hornbeam predominates on the area of 21.7% of the forested lands of the reserve. Preliminary investigations of the Reserve hornbeam plantations were conducted by Mykola Korol and Ihor Humeniuk. They pointed to the stability of these plantations, their high competitive abilities but depleted biotic potential. The objects, selected for the study, are permanent trial areas, where during the last taxation measurements the hornbeam dominations in the tree stands were observed (with the tree stands of 6 and more items). On the studied trial areas mature and overmature plantations prevail by age groups. The hornbeams grow here mainly in young hornbeam forests in the first, second and third bonitets. The predominant number of trees on the trial areas is hornbeam of seed origin. Except L-28, where the conditions of growth are dry oakery on the rock, the hornbeams grow on the third bonitet and are of sprouting origin mainly. The tree stands on the trial areas are of the same age. As for the age groups they are mature and overmature, except for L-13 and L-28, where the young stocks grow, and L-13, where the one of a middle age grow. The tree stands taxation indicators on the trial areas are characterized by some differences, depending on age and completeness, within different types. The stock of live wood is on average 115-463 cubic metres per hectare. Trees differentiations by the degree of thickness show the process of a plant formation depending on their origin and age. On the trial areas the renewal of a hornbeam is represented by one- and two-years-old undergrowth. The forest stands are characterized by insignificant variability of their taxation structure indicators, being the result of a slight influence of natural and anthropogenic factors.

Forecast‐Cartographic Modeling of Pasture Production of the Volgograd Region Based on Remote Sensing

Aim. The work is devoted to identifying the productivity of pasture landscapes in the Volgograd region. The aim was to determine the direction of trends and the values of the coefficients of proportionality which would permit the definition of areas where the productivity of natural zonal vegetation has increased or decreased from 2000 until today. Material and Methods. Pasture productivity assessment is based on the analysis of the NDVI vegetation index, which is widely used in such studies. For analysis, specific pasture areas were identified in accordance with Global Land Cover, divided into egular grids and given overlays corresponding with the boundaries of municipalities and landscapes. Results. The largest areas of natural zonal pastures are located in the Trans‐Volga region and on the sandy massifs of the Don River valley. About 60% of pasture land has an average weighted average long‐term NDVI value from 0.3 to 0.4, and approximately a quarter – from 0.4 to 0.5. In most parts of the region there are negative NDVI trends. The highest rate of degradation is noted in the Trans‐Volga region. This is associated with larger pasturing loads than in the rest of the region, as well as with the regular occurrence of steppe fires. Conclusion. In summation: the productivity trends of zonal pastures in the Volgograd region have been determined, as have areas with different NDVI directions and dynamics. The application of these results in practice should make it possible to predict pasture productivity in various municipal districts and landscapes of the region, and thus assist in the regulation of pasture loads and the mitigation of risks of vegetation degradation.