Climatic and soil-hydrological factors are fundamental for the formation of the stand composition and productivity of forest ecosystems. The human impact increase during the last century has led to the necessity of developing measures to preserve and enhance the reproduction of forest resources (Hensiruk 2002, Prots et al. 2010, Tkach 2012). Implementation of programs for forest resources conservation and their effective use has been activated in most countries in Europe as well as on a worldwide scale (FAO 1997, FAO 2014). Along with that, a necessity of developing an international and world-class concept emerged. Such a strategy was adopted in Rio in 1992 (UNCED 1992). At the UN conference, a strategy for Sustainable Forest Management (SFM) was announced, which would, on top of everything else, ensure the practical implementation of the principles of conservation and not exhausting use of forest resources (UNCED 1992). The concept of SFM has been implemented in most countries all over the world. Currently, several regional strategies have been developed in accordance with the forest management features in the countries of Europe, North America, Africa, Asia as well as tropical countries (ITTO 1993, UNEP/FAO 1998, Wijewardena 1998, Prabhu 1999, Montréal Process 2015, Sustainable Forestry Initiative 2010–2014). Most doctrines are based on the optimal combination of environmental, economic and social factors that would ensure forestry activity. Each of them contains certain Criteria and Indicators (C&I). SFM concept was accepted by Ukraine (Kravets and Lakyda 2002; Furdychko and Lavrov 2009). Almost all concepts contain an indicator that reflects the conservation of biological diversity. Forestry genetic resources are reflected in the Pan-European Strategy of Sustainable Forest Management in indicator 4.6. One of their most important characteristics is the area of forest genetic resources
Forest genetic reserves, plus stands and plus trees belong to objects of forest genetic resources conservation
The research of forest genetic reserves, plus stands and plus trees in the conditions of the Right-Bank Forest-Steppe was conducted during 2004–2018. Field work was carried out in Khmelnytskyi, Vinnytsia, Kirovograd, Odesa, Kyiv and Cherkasy regions. Data on surveyed reserves are listed in the international forest genetic resources database EUFGIS (EUFGIS 2006–2011). Based on the database, we analysed the distribution of genetic reserves and plus stands by their location, area, tree species composition of the stands and environmental conditions (biome, climate condition and soil type). The location of the surveyed stands is shown on the map (Fig. 1).
Forest genetic reserves and plus stands inventoried during 2004–2018 (map obtained using the EUFGIS portal)
For each object of gene pool conservation
where:
Σ
Vorobyov Climatic Index was calculated according to the formula (2):
where:
Indexes (Selianinov Hydrothermal Index and Vorobyov Climatic Index) make it possible to assess not only temperature conditions but also the level of humidity.
Soil characteristics are derived on the basis of spatial localization of forest genetic reserves. Information on soil types by international classification has been derived from the EUFGIS database.
Tree condition was assessed according to Sanitary rules in the forests of Ukraine and ICP-Forest Monitoring Program (Manual, 1998). We used a 5-point scale for the identification of trees condition (Sanitary rules in the forests of Ukraine 2016). The tree-breeding category (TBC) indicated for each tree at the sample plot (Veresin 1963).
Category 1 (plus trees) is the best trees for the whole set of features. In a one-year-old forest stands, they exceed the average DBH by at least 30% and 10% of average height. The trees are straight-stemmed, with good clearing from knots and branches, excellent quality of the trunk. They are in healthy, good or satisfactory condition, without mechanical damage, with normal fruiting.
Category 2 (best of normal) can have high-quality trunks that meet the requirements of plus trees of category 1, with a slight excess of average height and DBH, or have significant excesses in height and DBH, but have some defects in the trunks. They are in healthy, good or satisfactory condition, without significant mechanical damage, with normal fruiting.
Category 3 (normal trees) is trees that have a DBH and height at the level of average forest stands. They have defects in the quality of the trunks. They are in good or satisfactory condition, with mechanical and other damages.
Category 4 (minus trees) has trees poor in growth, quality and condition or one of these features. These include all undersized trees, as well as all trees of any size with pronounced defects.
Statistical analysis of the data included the collection, analysis and interpretation of data on forest genetic resources
Forest genetic reserves and plus stands are the main source of conservation and extended recovery of the gene pool of major forest species populations (Molotkov et al. 1993, Los et al. 2017). The largest area of deciduous genetic reserves is located in Zhytomyr, Chernivtsi and Vinnytsia regions – 2909.7 ha, 1826.1 ha and 1286.0 ha, respectively. The area of forest genetic reserves in other regions is much lower and ranges from 172.8 ha to 584.3 ha (Table 1).
Objects of
No | Region | Objects of |
||
---|---|---|---|---|
Forest genetic reserves area [ha] | Plus stands area [ha] | Number of plus trees, units | ||
1 | Vinnytsia | 1286.0 | 530.3 | 123 |
2 | Zhytomyr* | 2909.7 | 110.2 | 290 |
3 | Ivano-Frankivsk | 584.3 | 612.7 | 189 |
4 | Kyiv* | 351.0 | 40.9 | 152 |
5 | Kirovograd* | 238.0 | 0.0 | 74 |
6 | Odesa* | 172.8 | 5.5 | 25 |
7 | Ternopil | 189.4 | 0.0 | 157 |
8 | Khmelnytskyi | 355.9 | 99.9 | 148 |
9 | Cherkasy* | 319.4 | 0.0 | 137 |
10 | Chernivtsi* | 1826.1 | 3.3 | 276 |
Total | 7053.5 | 872.5 | 1448 |
Note: * the region territory partly belongs to the Right-Bank Forest-Steppe of Ukraine.
The largest plus stands area of deciduous tree species were selected in Ivano-Frankivsk and Vinnytsia regions – 612.7 ha and 530.3 ha, respectively. In Zhytomyr and Khmelnytskyi regions, the plus stands area is about 100 ha. There are no plus stands in Kirovograd and Cherkasy regions.
According to the investigation, the largest proportion of genetic reserves and plus stands is located in Vinnytsia and Lviv regions. In these regions, the proportion of forest genetic reserves from the total area is 30–40%. The proportion of surveyed forest genetic reserves in Kyiv, Cherkasy, Kirovograd and Odesa regions is only 1–5%. The total number of forest genetic reserves and plus stands is 124 (Fig. 2).
The share of forest genetic reserves and plus stands located within the limits of the Right-Bank Forest-Steppe of Ukraine
The largest number of objects, namely 27 and 25 units, is located in Ternopil and Khmelnytskyi regions, respectively. The smallest number of seed orchards, which is 4 and 6, is located in Zhytomyr and Cherkasy regions.
The total area of forest genetic reserves and plus stands in the Right-Bank Forest-Steppe is 4053.3 ha. The largest areas of
The predominant main forest-forming species of the forest genetic reserves of the Right-Bank Forest-Steppe are English oak, which stands take a share of 43.7%, and European beech – 31.5%. The stands with the predominance of Common ash cover 12.7% of forested area. The English oak and European beech have the largest number of genetic reserves – 53 and 43 units (44.9% and 36.3%, respectively; Tab. 2).
Number and area of forest genetic reserves for the main forest-forming tree species in the Right-Bank Forest-Steppe
Populations of main tree species | Number, units | Proportion of units [%] | Area [ha] | Proportion of [%] |
---|---|---|---|---|
1 | 0.8 | 1.8 | 0.0 | |
1 | 0.8 | 3.3 | 0.1 | |
1 | 0.8 | 13.0 | 0.3 | |
43 | 36.3 | 1275.9 | 31.5 | |
8 | 6.7 | 517.5 | 12.7 | |
9 | 7.5 | 449.4 | 11.1 | |
53 | 44.9 | 1773.3 | 43.7 | |
1 | 0.8 | 13.0 | 0.3 | |
1 | 0.8 | 6.1 | 0.2 | |
Total | 118 | 100.0 | 4053.3 | 100.0 |
According to the international classification of natural zones based on climate classification (Köppen-Geiger), the territory of the Right-Bank Forest-Steppe belongs to the zone of cold and dry climate (HI). The climate of the sites with the predominance of European beech is characterized by a better humidification level according to the precipitation-temperatures ratio (Selianinov HTI is 1.769–1.802; Vorobyov Climatic Index is 2.707–2.951). Lower precipitation for the year (589–598 mm) and the growing season are specific for the stands of Sessile oak, English oak and Common ash. The precipitation/accumulated temperatures ratio for associations with the predominance of these tree species is the lowest (Selianinov HTI is 1.245–1.290; Vorobyov Climatic Index is 0.830–0.946; Tab. 3).
Evaluation of precipitation and climatic parameters of genetic reserves by Vorobyov and Selyaninov indices
Genetic reserves (tree species) | Σ |
Σ |
Selianinov HTI [ |
Vorobyov Climatic Index [ |
---|---|---|---|---|
608 | 440 | 1.541 | 2.048 | |
664 | 493 | 1.649 | 2.252 | |
581 | 382 | 1.182 | 0.597 | |
668 | 486 | 1.679 | 2.432 | |
633 | 466 | 1.610 | 2.220 | |
603 | 416 | 1.372 | 1.364 | |
632 | 444 | 1.473 | 1.691 | |
646 | 463 | 1.565 | 2.022 | |
654 | 485 | 1.584 | 1.982 | |
Average | 641 | 457 | 1.535 | 1.914 |
The
Distribution of the total number of units and area of genetic reserves in the Right-Bank Forest-Steppe on the prevailing soil types according to the international classification (EUFGIS)
Soil types | Quantity [units] | Proportion from the total number [%] | Area [ha] | Proportion from the total area [%] |
---|---|---|---|---|
Dystric Fluvisols | 1 | 0.8 | 18.0 | 0.4 |
Dystric Gleysols | 1 | 0.8 | 2.4 | 0.1 |
Eutric Fluvisols | 1 | 0.8 | 15.0 | 0.4 |
Eutric Podzoluvisols | 8 | 6.8 | 175.2 | 4.3 |
Gleyic Phaeozems | 5 | 4.2 | 368.1 | 9.1 |
Gleyic Podzoluvisols | 1 | 0.8 | 58.0 | 1.4 |
Haplic Chernozems | 11 | 9.3 | 334.7 | 8.3 |
Haplic Greyzems | 67 | 56.8 | 1903.3 | 47.0 |
Haplic Phaeozems | 2 | 1.7 | 194.4 | 4.8 |
Luvic Phaeozems | 16 | 13.6 | 741.6 | 18.3 |
Rendzic Leptosols | 2 | 1.7 | 20.3 | 0.5 |
Stagnic Podzoluvisols | 3 | 2.5 | 222.3 | 5.5 |
Total | 118 | 100.0 | 4053.3 | 100.0 |
Meadow-chernozem soils (Luvic Phaeozems) make up a significantly lower share – 16 units (13.6%) – and in terms of an area – 741.6 ha (18.6%). The number of genetic reserves on chernozems (Haplic Chernozems) is 11 (9.3%) with a total area of 334.7 ha (8.3%).
Associations with the English oak predominance are mainly distributed on grey forest soils (Haplic Greyzems). The total number of sites characterized by this soil type is 26 (49.1%) with a total area of 1091.4 ha (61.5%). The largest areas of oak-ash associations are located on meadow-chernozem soils (Gleyic Phaeozems) – 59.4 ha (3.3%). However, the largest number of these association sites, 3 (5.7%), is concentrated on grey forest soils (Haplic Greyzems). Oak-pine associations are limited to light-grey forest soils (Eutric Podzoluvisols) with a total area of 73.0 ha (4.1%). The English oak associations interspersed with Sessile oak are distinguished by prevailing meadow-chernozem soils (Luvic Phaeozems) with a total area of 28.0 ha (1.6%). Forest formations of European beech are mainly represented by meadow-chernozem soils (Luvic Phaeozems) and grey forest soils (Haplic Greyzems). The largest association area is 390.5 ha with the meadow-chernozem soils predominance. The number of areas with grey forest soils is the largest and aggregates 29 units (67.4%) with a total area of 363.9 ha. A significant area of 264.6 ha (20.7%) is occupied by Gleyic Phaeozems, which is typical for 3 sites. For ash associations interspersed with English oak and Sessile oak, the predominance of grey forest soils (Haplic Greyzems) is typical (312 ha, 49.1%). There are 2 plots (16.7%) on these soils. The same soil types are typical for ash-oak associations – 83.0 ha (13.1%). Luvic Phaeozems and Haplic Chernozems are the prevailing soil types for the Sessile oak association with an admixture of English oak and ash, 186.1 ha (34.4%) and 182.4 ha (33.7), respectively.
According to the investigation of stands dynamic during last 20 years, we observed a decrease of the proportion of English oak in tree species composition, destruction of stands, deterioration of the tree-breeding structure of stands and deterioration of tree stands health condition (Tab. 5).
Distribution of surveyed forest genetic reserves and plus stands (%) according to the dynamics of the state during the last 20 years
Region | Reduction of the proportion of the main forest-forming species in the composition by more than 20% | Decrease in the relative density of stocking of stands below 0.7 | Decrease of the tree-breeding category (below 3.0) | Weakening of trees (average category of health condition below 3.0) |
---|---|---|---|---|
Vinnytsia | 7.7 | 3.1 | 1.5 | 15.4 |
Kyiv | 7.7 | 1.5 | 1.5 | 1.5 |
Kirovograd | 0.0 | 0.0 | 10.0 | 0.0 |
Odessa | 4.6 | 9.2 | 4.6 | 4.6 |
Khmelnytskyi | 4.6 | 10.8 | 0.0 | 0.0 |
Cherkasy | 1.5 | 0.0 | 0.0 | 1.5 |
Total | 26.2 | 24.6 | 17.7 | 23.1 |
A significant part of the surveyed forest genetic reserves is characterized by deterioration of the health condition and selection structure. The decrease of the functional suitability of the gene pool
Forest genetic resources are an important component of the biodiversity of forest stands conservation. Preservation of forest genetic resources
Forest genetic reserves and plus stands selected in Ukraine are fully in line with the criteria for forest genetic resources conservation
Significant fragmentation of the forest gene pool conservation objects
The provision of natural seed regeneration of stands that are part of forest genetic reserves is another important aspect. Currently, the selection of the forest gene pool conservation