There is a close relationship between climate change on Earth and the state of forests. Extreme weather conditions, changes in the average annual temperature, and precipitation adversely affect forests (FAO, 2021; ShareAmerica, 2020; WWF, 2018). Since 1990, the Earth has suffered from the loss of 420 million hectares of forest lands due to logging for the needs of farmers, miners, and industrialists. The equatorial forests have been destroyed the fastest. Brazil, Bolivia, and Indonesia were the most affected countries by forest loss due to commercial logging and frequent fires. Academicians of the University of Southampton (England) and George Mason University (Virginia, USA) claim that the Amazon forests will disappear in the next fifty years if the current rate of deforestation continues. Europe has not escaped the worse fate either. Half of its territory is still covered by forests, which absorb almost 10% of all carbon dioxide (CO2) emissions in The Old World. The dry summer in 2019 and 2020 caused terrible forest fires and large-scale tree diseases. Over the past half-century, the composition of European forests has changed, and their ability to absorb carbon dioxide has decreased. The European Commission indicates that increased demand for timber and frequent fires prevent trees from reaching the age when they absorb the maximum CO2 (FAO, 2021; IPCC, 2001, 2013; Itter
Increasing weather phenomena that pose a danger for forests on the territory of Russia are recorded by forestry statistics (from two hundred to four hundred manifestations from 1990 to 2010). For example, weather patterns destroyed 21 thousand hectares of forests in the 1990s; at the end of the 2000s, 53 thousand hectares were depleted. Adverse weather is likely to affect the Russian economy and the forest sector in the future (FAO, 2020; ShareAmerica, 2020; WWF, 2018). In turn, plants, depositing carbon dioxide, make an invaluable contribution to mitigating the effects of global warming. Trees play an essential role in fighting against climate change, as they absorb and store carbon dioxide throughout their lives. The United States takes part in the the Trillion Tree Campaign (ShareAmerica, 2020) to ensure the absorption of 25% of the total carbon dioxide emissions caused by human activity. According to the campaign company Plant-for-the-Planet, this will combat global warming at the level of two degrees Celsius (ShareAmerica, 2020). However, logging and forest fires are a source of carbon dioxide (CO2), contributing to the greenhouse effect (IPCC, 2013; USGCRP, 2017). Therefore, there is a need for a comprehensive approach to solving these urgent issues.
Academia to date has not got across a common point of view about the apparent relationship between the causes and consequences of increased CO2 and global warming. In 1992, many countries joined the United Nations Framework Convention on climate change to reduce industrial emissions of all greenhouse gases into the atmosphere. The 2015 Paris Agreement provides measures to reduce CO2. The International Group on Climate Change claims that the global average temperature is more likely to increase by 1.4–5.8°C until 2100 (Bobrik, 2015), and change the composition and structure of the vegetation cover (Ministry of Forestry of the Republic of Bashkortostan, 2019; VNIIGMI-MCD, 2021; WWF, 2018).
To date, the study and making the observed climate transformations relevant for forest ecosystems is one of the significant issues both at the level of fundamental research and at the level of socio-economic development of the country’s regions (Cortés
This study aimed to analyse and compare the forest species placement in the RB over the last decades in climate change conditions.
To achieve this goal, the research examined the impact of climatic transformations on forest composition. It developed recommendations and measures to reduce losses in the forest sector from the emerging changes and preserve the biodiversity of the forest ecosystem.
The RB is among the leading regions of the Russian Federation with a high resource and environmental potential. The current climate change affects urban and forest ecosystems in one way or another (Isyanyulova
The research target is the entire territory of the RB (Figure 1). Its flora is mainly determined by its location at the junction of the Urals with the West Siberian Lowland, the Cis-Ural Plain and steppes. The republic’s vegetation is a multi-species diversity, numbering more than one thousand seven hundred plants (City District Council Ufa City of the Republic of Bashkortostan, 2019). Forests in Bashkortostan until the 19th century occupied more than 70% of the total area of the current region, with a predominance of conifers and hardwoods (Muldashev, 2020).
Changes in climatic patterns (average temperature and precipitation during the year) were estimated over the last fifty years (VNIIGMI-MCD, 2021). Forest characteristics rely on the forest fund data, forest management documents (Acting Head of the Republic of Bashkortostan, 2018; City District Council Ufa City of the Republic of Bashkortostan, 2019; Ministry of Forestry of the Republic of Bashkortostan, 2019) for a comparative analysis of the forest species placement, materials of route surveys and field studies conducted by generally established forestry methods (Verkhunov & Chernykh, 2007). Our research covered areas with the main forest-forming tree species in the region. Tree species were identified and analysed according to the reporting documents of the state forest register. Trial plots are set to study the ongoing processes in the forest during the entire observation period in the same soil conditions under the Russian forestry standard OST 56-69-83 “Trial plots in forestry. Sampling establishment”. In the corners of the trial plots, mine shafts were installed with a compass according to industry standards 56-44-80 “Field signs for forest management and forestry. Types, sizes and general technical requirements”. The tree trunk diameter was measured at the height of 1.3 metres in two directions using a measuring fork (with an accuracy of 0.5 centimetres). The tree height was estimated with a SUUNTO RM-5/1520 altimeter (accuracy 1–2%). The stand vital condition was assessed according to the VA Alekseev’s method: healthy, damaged (weakened), severely damaged (severely weakened), dying trees, newly and long-ago dead stands (Alekseev, 1989). In some cases, in addition to assessing the vital state of the stand, it is rational to find its damage. This examination takes into account weakened, severely weakened and destroyed trunks. The comprehensive research ended with an analysis of the findings using Microsoft Excel 2019.
According to forecasts based on different scenarios for the future development of the Earth’s climate, carbon dioxide concentrations and the average temperature will increase by 2100. The carbon content in the atmosphere will vary from 10 to 30%. The planet’s average temperature from the early 1990s to 2100 will be rising by 1.4–5.8°C. Warming rates are likely to be very high over the last hundred thousand years. From 1990 to 2025 and 2050, the predicted growth will be 0.4–1.1°C and 0.8–2.6°C, respectively (Gil & Zajączkowski, 2014; Hemery
Both around the world and on the territory of Russia, the warming rate continues to exceed the global average. The Institute of Global Climate and Ecology, named after Academic YA. Israel (IGKE) recorded the average air temperature increase in the Russian Federation in 1976–2019, which was 0.47°C for ten years. The Hadley Centre for Climate Prediction and Research and the University of East Anglia (UEA) found that this indicator was more than two and a half times higher than the global temperature increase (0.18°C) over the decade and one and a half times more than the surface air warming (0.28°C). The temperature value of each decade since 1980 has exceeded the previous indicator. The Northern Polar region faced the most drastic temperature rise. The Arctic and Antarctic Research Institute (AARI) analysed the average annual temperature from 1990 to 2019 and revealed its rise to 0.81°C for ten years, that is 2.43°C (Glaesaer, 2006; IPCC, 2001). The rapid reduction of the Arctic ice cover indicates accelerated warming.
The high concentration of carbon dioxide released during fuel combustion into the atmosphere leads also to global warming and, consequently, the planet’s climate change. Forests can deposit carbon from the atmosphere, which is “stored” in the form of wood and vegetation (Khanova
Current attempts of the world community to cut greenhouse gas emissions fail to reduce their concentration and prevent the temperature increase.
The Federal Hydrometeorological Service (northern background stations) indicates the constant growth of carbon dioxide by an average of 2.26 million−1/year. In 2019, this indicator reached the maximum level; the average annual value was 414 million−1. There is also an increase in methane fixation.
According to observations, 2019 became the warmest for Russia since 1936: the average annual temperature exceeded the norm by 2.07 degrees Celsius (the average for 1961–1990) and there were abnormal climate manifestations. Spring witnessed an average temperature index of 2.86 degrees Celsius above normal. High temperatures were observed in the south of the European part during June: in the North Caucasus Federal District (4.26 degrees Celsius above normal) and the Southern Federal District (4.29 degrees Celsius above normal), while the precipitation deficit exceeded the norm by 46%, resulting in an inevitable drought. December in 2019 was extremely warm in the European part of Russia.
It was very warm in the Northern Polar region with an abnormal temperature of +2.5 degrees Celsius (after 1936). Since the nineties of the last century, the rapid increase in Arctic temperatures has reduced sea ice in the Arctic Ocean (its area amounted to one hundred thousand square kilometres in 2019).
Temperature changes resulted in the troposphere warming (the warmest values were observed from 2015 to 2019) and cooling of the stratospheric layer (for example, 2019 was the most abnormally cold with −1.01°C for last years) (Roshydromet, 2019).
The study of the annual temperature transformations over the last century revealed a certain tendency to increase (Bahna, 2020; Isyanyulova
The results of a ten-year study by the Laboratory of Specially Protected Natural Territories and Biological Resources of the Research Institute of Life Safety of the Republic of Bashkortostan indicate dryness of certain forest lands while maintaining a decrease in biomass growth and changes in tree condition.
The annual precipitation in the republic generally increased from 1966 to 1996, but by 2012 it decreased (Volkov
To understand humidification conditions in a particular territory, the hydrothermal (according to G.T. Selianinov) and humidification (according to Ivanov-Vysotskii) coefficients were analysed. The finding demonstrates the synchronic distribution of the curves and uniform changes in hydrothermal indicators in different areas and, accordingly, the entire region as a whole (Galimova
The conducted analysis of the current state of the agro-climatic resources in the RB (Galimova obvious changes in the agro-climatic conditions for the region as indicated by the total indicators of active and positive atmospheric temperatures and the climatic index of biological efficiency; synchronicity and dynamics of the Ivanov-Vysotskii humidification coefficient and the Selianinov’s hydrothermal coefficient, although there were no significant changes in hydrothermal indicators; transformations in climate dynamics; increasing tendency towards arid conditions during the period of positive temperatures observed in the southern parts of the republic.
The long-term study of changes in the forest composition makes it possible to assess the effects of different natural patterns with a pivotal role of climate conditions that develop the phytocenotic structure. Adverse consequences for forestry became evident due to the higher temperature regime and reduced precipitation.
It should be noted that the period from 1989 to 2019 is characterised by an early transition of air temperature from zero degrees Celsius towards an increase and snow-melting for ten days, compared with previous years. A decrease in the snow cover depth by an average of five centimetres results in reduced moisture reserves by almost a quarter of the level of long-term indicators. Frequent thaws cause evaporation of meltwater in winter or its running into water reservoirs, which negatively affects groundwater depth.
The growing season starts earlier, and its period has lengthened by an average of twelve days.
Climate changes have led to the observed dynamics of the forest species composition.
The area of the RB’s forest fund totals 5.7 million hectares or 39.9%. The area under forest in the Russian Federation is 46.6%, with 36.5% in the Volga Federal District. The total wood reserves in the republic amount to about 769 million cubic metres. Soft-leaved species predominate on 3559 thousand hectares. Coniferous trees occupy 1145 thousand hectares and hardwoods about 459 thousand hectares.
The ratio by groups and timber resources is as follows:
coniferous forests occupy 17% of the forest land and make up 24% of the total stock; hard-leaved trees take up 7% of the stock; soft-leaved trees account for 76% and 69%, respectively (FAO, 2021).
The share of the RB species by distribution and timber resources is given below:
Among coniferous trees:
Analysis of the soft-leaved tree distribution showed the predominance of
The expected forecast for reduced coniferous areas and increased mixed and broad-leaved forest stands is mainly due to climate transformation (Figure 2).
Based on findings of the World Wide Fund for Nature, the University of Eastern Finland and the Swedish Forest Agency, it is expected that spruce forests will suffer the most significant losses from climate transformation (IPCC, 2001).
It should be noted that the obtained results for the RB coincide with changes in the forest composition of the Scandinavian countries. In some European countries and on the territory of the republic,
Researchers put forward the establishment and preservation of forest territories as one of the options for combating climate transformations. It can be achieved by restoring forests on cut-down areas, growing new ones and protecting them from deforestation.
According to the global forest resources assessment in 2020, 93% – that is, 3.75 billion hectares of the world’s forests are naturally renewable, and 7% – 290 million hectares are forest crops. Since 1990, the areas of naturally renewable forests and their reduction rate have slowed down, but at the same time, the area of forest crops has increased by 123 million hectares (Gil & Zajączkowski, 2014; Roshydromet, 2019). However, the growth rate of the territory under forest crops has declined in the last decade.
Forests on the republic’s territory are restored by 32 forestry enterprises, the state forest management institution, the Center for the Prevention and Extinguishing of Forest Fires, and forest tenants. The RB’s Ministry of Forestry also controls the Ufa Technical School. The annual allowable logging, i.e., the calculated cut, is about nine million cubic metres (including more than one million cubic metres for coniferous forestry systems). According to this indicator, the republic ranks third in the Volga Federal District (VFD) after the Kirov Region and the Perm Territory.
More than one and a half million hectares are leased forest plots of over three million cubic metres. 96% or 1.4 million hectares are accounted for timber harvesting. Forest plots are also allocated for recreational activities (for 662 forest users), agriculture (1222 people), linear objects (514 people), etc. (Acting Head of the Republic of Bashkortostan, 2018) (Figure 3).
On the RB’s territory, tenants planned reforestation work on an area of about 6000 hectares or 51% of the total volume for this type of activity. According to the RB’s forestry development forecasts, the ratio of logged forest stands should correspond to the area of reforestation in 2019–2024 (Figure 4).
The republic is leading in the Volga Federal District in terms of seed sowing in nurseries. The sowing plan is 120% complete. To increase the reforestation rate, both naturally and artificially, the project “Forest Conservation” was adopted at the federal level to “ensure a balance of forest disposal and reproduction in the ratio of one hundred percent by 2024” (Ministry of Forestry of the Republic of Bashkortostan, 2019).
For comparison, the activities of the Food and Agriculture Organization of the United Nations (FAO) in the field of forestry are aimed at:
popularisation of the global reforestation movement within the framework of United Nations Decade for Ecosystem Restoration, held under the auspices of FAO; expanding the scope of forest and landscape restoration at the basic level within the framework of the Mechanism for the Restoration of Forests and Landscapes, the project “Measures to combat desertification” and restoration initiative financed by the Global Environment Fund; participation in one of the recent United Nations initiatives supporting the Great Green Wall campaign (FAO, 2020).
The Ufa city forestry of the Ufa city district has three forest nurseries on a total area of about one hectare. There are also plantations of large-sized seedlings of trees and bushes on an area of 38.4 hectares. Planting material is grown in the volumes of the needs of the Ufa city for landscaping and reforestation on the territory of urban forests. The periods and characteristics of forest use to grow seedlings are applied for a particular territory and recorded in the relevant documents, including forest development projects after the conducted additional surveys.
Combined reforestation is carried out in areas where the natural restoration of valuable tree species forest stands is not provided. Seedlings or undergrowth preserved during logging are planted within a year from the cut forest stands.
Areas with forest crops laid down artificially and in a combined way are considered covered with forest vegetation when characteristics of the main species match the reforestation rules.
Analysis of urban forest crops in Ufa revealed that non-adjusted plants occupy more than 32 hectares, transferred to the land covered with forest vegetation – 5.5 hectares. Age-related forest crops are located on a territory of 2474 hectares. In addition, forest crops under the forest canopy occupy 148 hectares. Old plants in an unsatisfactory state take up 67 hectares, of which
The analysis showed a clear tendency to reduce the share of coniferous species on the republic territory on the example of
Long-term research on changes in the phytocenotic structure of plantings makes it possible to assess the impact of natural factors, including climatic conditions. The consequences of climate transformations have a significant impact on forest resources. In the territory of the republic, large areas suffered from birch disease. Scientists attribute one of the negative causes of bacterial dropsy in
The sanitary forest inspections detected mechanical damage to the trunk and roots, destructions caused by insects and animals, frost clefts, other diseases on an area of 4431 hectares, including the root sponge on 399 hectares. Significant areas of plants on 10,181 hectares were affected by weather conditions and soil and climatic factors, and 519 hectares were affected by forest fires (Ministry of Forestry of the Republic of Bashkortostan, 2019). Studies of plant diseases and damage revealed “traces” of coniferous, leaf-eating and trunk pests (the affected areas are shown in Figure 5).
The analysis of tree diseases and damage on the republic’s territory showed that the most common reason for tree death are insects. In 2012, experts assessed the forest condition in Bashkortostan as satisfactory. The conducted monitoring did not detect any large foci of forest insect pests in the republic. As reported by the Forestry Ministry’s Department of Forest Control and Protection in the RB, the largest forest pest centre of jewel beetles (
It should be noted that foreign scientists also explore climate change models, predict scenarios and expected consequences (Duveneck & Thompson, 2017). With the development of a warm climate scenario, there are increased outbreaks of destructive insects in Central Europe, North America and China (Duveneck & Thompson, 2017; Huang
The present research found a gradual shift in the main forest species and the
Thus, planning forestry activities in regions requires measures to use competitive advantages in the conditions of climate transformation based on academic, scientific and technical achievements. At the regional level, it should be noted that the RB’s government is interested in effective conservation and protection of forests, their useful properties, resources to achieve a balance of disposal and restoration, increase productivity and quality, growing forest stands resistant to external influences following the legislation at the federal and republican (local) levels through the development of international cooperation and experience exchange.
The conducted comparative analysis of the forest species distribution on the territory of the Bashkortostan Republic in the conditions of climate transformation over the last decades showed the following:
during the studied period from 1998 to 2018, the share of soft-leaved species by area has significantly increased, primarily the areas under coniferous species tend to decline; there was a cut in
The expected forecast for reduced coniferous areas and increased mixed and broad-leaved forest stands is mainly due to climate transformation.
The increased sum of active temperatures and vegetation length by an average of twelve days can be considered as positive impacts of climate change. It is beneficial for wood growth. The wood reserves in the RB will increase by more than 10%.
There is a high probability of more negative manifestations in the form of forest diseases and pests, windstorms, fires due to climate transformation, which has already caused a mass disease of birch trees in all the republic’s districts in the last years.
The present study found that under warmer climatic conditions, there will be an increase in the number of destructive pests by several times, damaged plants on an area of up to ten thousand hectares and a reduced area of spruce forests by 20% over the last twenty years.
The Russian regulatory framework of forest management was amended by the section on forestry adaptation, including the forest plans of the regions to mitigate climate transformations. However, they provide general provisions and no specific forestry measures. Therefore, the authors of the present study believe that there is a need for collaborative work between public environmental and scientific organisations and authorities to develop specific measures for adapting forestry to the consequences of climate transformations and introducing them into regional forest management regulations. Currently, to address the issues of minimising forestry losses during sustainable climate changes and getting possible benefits from them, the Russian Government is preparing an Environmental Development Strategy for the period up to 2050, which will help the world community maintain ecological balance.
Further research should be undertaken to continue the analysis, spatial modelling and study of the ecophysiological reactions of species to changes in environmental factors, and their competition that will contribute much to the studies in this field.