scholarly journals Лісівничо-екологічний аналіз насаджень Populus alba та Populus nigra на ріках лівобережного лісостепу України

2017 ◽  
Vol 7 (1) ◽  
pp. 84-91
Author(s):  
O. B. Bondar ◽  
L. I. Tkach ◽  
I. S. Lisina ◽  
M. S. Kolienkina ◽  
S. I. Musiyenko

<p>Here the sylvicultural and ecological analysis of typological structure of plantings silver and black poplar are presented for the riverine habitats of the Psel, Sula and Vorskla (the middle reaches of Seversky Donets river). Our analysis was based on forestry management electronic databases of Ukrainian National Forest Project Enterprise.</p><p>More than 38 forest types on the area of 4.9 thousand hectares were examined. The biological features of silver and black poplar were described briefly. The silver and black poplar reproduction pattern of the Left-bank Forest-steppe of Ukraine was also examined. There was carried out the area allocation of tree species according the following points: forest type and origin, forest site quality, closure degree and age groups. By the tree stratum origin silver and black poplar are mostly artificially propagated, what is equivalent to 77.3 and 88.3 percent.</p><p>The silver and black poplar area around the rivers’ watershed of the Left-bank Forest-steppe of Ukraine occupies 2813 and 2173 ha consequently.</p><p>Among forest types on research subject there are some forest types which dominate:  fresh quercetum fluvialis (25.0 %), wet quercetum fluvialis (17.4 %), wet quercetum-birchbark-maple fluvialis (16.3 %), wet lime tree-oak-pine tree sudubrava (11.4 %), fresh lime tree, oak, pine tree sudubrava (5.2 %), the rest of tree types represents less than 4.0 % of the total land area, covered with sylva. The silver and black poplar plantings’ distribution according to the site quality of forest on the rivers’ columbine of the Left-bank Forest-steppe of Ukraine can be described in the following way: II and IV classes of the site quality of forest prevail, and the medium stocked tree stratum fluctuates from 52.9 to 87.8 per cent according to the normality.</p>

Author(s):  
V. P. Tkach ◽  
O. V. Kobets ◽  
M. G. Rumiantsev

The forest site capacity using was quantitatively assessed for the stands of the main forest-forming species of Ukraine, Scots pine and common oak, taking into account natural zones and forest types. The tables of productivity of modal and highly productive pine and oak stands have been developed. It has been found that the stands use an average of 50–75 % of the forest site capacity of lands. The average weighted value of the capacity used by pine forests was 68–76 % in the Polissya zone, 70–78 % and 68–73 % in the Right-bank and Left-bank Forest-Steppe zones respectively, and 54–78 % in the Steppe zone. For oak stands, the value was 71–75 % and 63–71 % for the Right-bank and Left-bank Forest-Steppe zones respectively and 65–75 % for the Steppe zone. The basis for increasing the productivity of forests was confirmed to be the differentiation of forest management systems and individual forestry activities on a zonal and typological basis.


Forests ◽  
2019 ◽  
Vol 10 (3) ◽  
pp. 226 ◽  
Author(s):  
Karin van Ewijk ◽  
Paul Treitz ◽  
Murray Woods ◽  
Trevor Jones ◽  
John Caspersen

Over the last decade, spatially-explicit modeling of landscape-scale forest attributes for forest inventories has greatly benefitted from airborne laser scanning (ALS) and the area-based approach (ABA) to derive wall-to-wall maps of these forest attributes. Which ALS-derived metrics to include when modeling forest inventory attributes, and how prediction accuracies vary over forest types depends largely on the structural complexity of the forest(s) being studied. Hence, the purpose of this study was to (i) examine the usefulness of adding texture and intensity metrics to height-based ALS metrics for the prediction of several forest resource inventory (FRI) attributes in one boreal and two Great Lakes, St. Lawrence (GLSL) forest region sites in Ontario and (ii) quantify and compare the site and forest type variability within the context of the FRI prediction accuracies. Basal area (BA), quadratic mean diameter-at-breast height (QMD), and stem density (S) were predicted using the ABA and a nonparametric Random Forests (RF) regression model. At the site level, prediction accuracies (i.e., expressed as RMSE (Root Mean Square Error), bias, and R2) improved at the three sites when texture and intensity metrics were included in the predictor set, even though no significant differences (p > 0.05) could be detected using the nonparametric RMANOVA test. Stem density benefitted the most from the inclusion of texture and intensity, particularly in the GLSL sites (% RMSE improved up to 6%). Combining site and forest type results indicated that improvements in site level predictions, due to the addition of texture and intensity metrics to the ALS predictor set, were the result of changes in prediction accuracy in some but not all forest types present at a site and that these changes in prediction accuracy were site and FRI attribute specific. The nonparametric Kruskal–Wallis test indicated that prediction errors between the different forest types were significantly different (p ≤ 0.01). In the boreal site, prediction accuracies for conifer forest types were higher than for deciduous and mixedwoods. Such patterns in prediction accuracy among forest types and FRI attributes could not be observed in the GLSL sites. In the Petawawa Research Forest (PRF), we did detect the impact of silvicultural treatments especially on QMD and S predictions.


2016 ◽  
Vol 1 (2) ◽  
pp. 15-18
Author(s):  
Романько ◽  
Yuriy Romanko ◽  
Мельник ◽  
Andrey Melnik

The research purpose was to identify high-quality variety features of formation of yield capacity and quality of soybean seeds when applying seniccation and desiccation in the Left-bank forest-steppe of Ukraine. The research subject is Anna, Romance, Vasilkovskaya varieties of soybean, the elements of technology of cultivation (desiccation and seniccation), yield capacity and quality of seeds. The experiment was carried out according to the two-factor scheme in a 4-times repeat at the Institute of Agriculture of the Northeast of NAAS of Ukraine. The research results showed that the duration of vegetation was influenced both by varietal characteristics and the application of desiccation and seniccation. On average, the smallest period from the growing phase to the full ripeness was stated on the variant with Reglon Super 2.0 l/ga and Basta 2.0 l/ga desiccation (36-37 days). The maximum level of yield capacity on the average in 2007-2009 was obtained from Vasilkovskaya variety – 2.50 t/ga. Annushka variety provided significantly lower yields (2.0 t/ha), as it was proved by the calculated NSR05. In terms of yield capacity Romantika variety took an intermediate position of 2.38 t/ga. On the variants with the application of seniccation and desiccation a positive trend of their influence on the yield capacity of soybean seeds in all studied varieties was stated. So, on average, an increase of yield capacity was stated when applying: seniccation 5.0% solution of ammonium nitrate per 0.38 t/ga; 8.0% solution of urea per 0.45 t/ga; Reglon Super 2.0 l/ga per 0.24 t/ga; Basta 2.0 l/ga 0.3 t/ga as compared to the control. Application of seniccation favored the increase of protein content: urea solution by 0.7%; solution of ammonium nitrate by 0.5% compared to the control. On the variants of desiccation the protein content was at (33.9-34.1%). Oil content of the seed of studied varieties ranged from 20.0 to 24.1%.


Author(s):  
V. L. Meshkova ◽  
V. L. Borysova

The incidence of ash dieback in the forest-steppe part of Sumy and Kharkiv Regions was analysed taking into account the type of forest site conditions, the stand age, relative stocking density, site index class and the proportion of European ash in the stand composition. Ash dieback is quite widespread in inspected stands of the Left-Bank Forest-Steppe of Sumy and Kharkiv Regions. The disease spreads similarly in natural and artificial stands. It was more often revealed in the fresh fertile forest site conditions, however, such forest site conditions are the most spread and the most favourable for European ash. It was found that ash dieback incidence tends to grow with a stand aging and lasts up to the stand’s age of 80. It can be explained by the development of stem and collar rots which occur later. Ash dieback incidence is the highest in the stands with 40–70 % of ash in their composition, at a relative density of stocking over 0.5 in the stands of different site index classes.


Author(s):  
O. B. Bondar

The results of investigations of actual and water protection forests coverage on the river catchments within the Left-Bank Forest-Steppe zone in Ukraine are presented. In the catchment areas of the Sula, Psel, Vorskla, Siversky Donets river, tree stands were distributed by the age groups, relative density, site classes, forest categories based on the data from the electronic database of “Ukrderzhlisproekt” Production Association. The percentages of natural and planted pine stands were determined in the fresh oak-pine fairly infertile site type and of oak stands, in fresh maple-lime fertile oak forest type. The productivity for natural and planted oak stands were analyzed in fresh maple-lime fertile oak forest type as well as for planted pine stands in fresh fairly infertile oak-pine site type.


Author(s):  
V. L. Meshkova ◽  
V. L. Borysova

The age structure of European ash stands in the forest fund of ten forest enterprises from Sumy, Kharkiv and Poltava regions was analyzed considering forest site conditions, stand origin, site index and ash proportion in the forest composition. The average age of ash stands is 68 years for the Left-Bank Forest-Steppe. On average from 46.1 % to 81.6% of European ash stands survive up to the V age class. The average age of ash stands is the highest in the forest-steppe part of Sumy Region in D2 and D3, in Kharkiv Region in D1, and in Poltava Region in C2 and C3. The average age is the highest (75 years) in artificial seed stands in Kharkiv Region, in natural seed (86 years) and vegetative (77 years) origin in Sumy Region. The survival of pure and almost pure ash stands is the highest in Kharkiv Region and the lowest in Poltava Region. In the legislatively adopted maturity age (VIII age class) survival of European ash with its proportion of 80–100 % is 26.5 %, 13.1 % and 3.2 % in Kharkiv, Sumy and Poltava Regions respectively. Correction of the main felling age in forests that are possible for exploitation is suggested considering the possible loss of timber quality as a result of forest damage by different causes.


2021 ◽  
Vol 13 (4) ◽  
pp. 696
Author(s):  
Dinh Ho Tong Minh ◽  
Yen-Nhi Ngo ◽  
Thu Trang Lê

Forest type classification using spaceborne remote sensing is a challenge. Low-frequency Synthetic Aperture Radar (SAR) signals (i.e., P-band, ∼0.69 m wavelength) are needed to penetrate a thick vegetation layer. However, this measurement alone does not guarantee a good performance in forest classification tasks. SAR tomography, a technique employing multiple acquisitions over the same areas to form a three-dimensional image, has been demonstrated to improve SAR’s capability in many applications. Our study shows the potential value of SAR tomography acquisitions to improve forest classification. By using P-band tomographic SAR data from the German Aerospace Center F-SAR sensor during the AfriSAR campaign in February 2016, the vertical profiles of five different forest types at a tropical forest site in Mondah, Gabon (South Africa) were analyzed and exploited for the classification task. We demonstrated that the high sensitivity of SAR tomography to forest vertical structure enables the improvement of classification performance by up to 33%. Interestingly, by using the standard Random Forest technique, we found that the ground (i.e., at 5–10 m) and volume layers (i.e., 20–40 m) play an important role in identifying the forest type. Together, these results suggested the promise of the TomoSAR technique for mapping forest types with high accuracy in tropical areas and could provide strong support for the next Earth Explorer BIOMASS spaceborne mission which will collect P-band tomographic SAR data.


Purpose. The study of changes in the main agrochemical parameters in the upper layers of the gray forest soils of the Left Bank Forest-Steppe of Ukraine that were removed from agricultural processing and forested with pine, in different years. Methods. Theoretical methods included the collection and description of facts, their analysis. Empirical methods involved conducting field research on test plots of the state-owned enterprise “Chuguevo-Babchansky LG” and farm near woodlands. Laboratory and analytical studies were performed using standardized measurement methods. The generalization of the experimental data was performed using application software packages. Results. Studies were carried out on soils under natural forest plantations, soils in intensive agricultural processing and unproductive soils that are derived from agricultural use. In all the studied soils, the main agrochemical parameters were compared among themselves: mobile forms of nitrogen, pH, humus content, content of common forms of nitrogen, phosphorus and potassium. Statistical dependences between agrochemical parameters in the studied variants were established. Conclusions. The results obtained indicate the revitalization and development of humification and accumulation of nutrients in old arable gray forest soils with an increase in the duration of exposure to pine forest. The age stages of the forest determine the specifics of the environmental factors that influence the soil-forming processes. In the soil of a young pine-tree (12 years), there are more cases of an increase in the coefficients of spatial variation. This indicates that the formation of young ecosystems are characterized by low resistance, in these biocenoses the dynamic equilibrium is not reached, which is characteristic of more mature pine forests.


Author(s):  
V. L. MESHKOVA ◽  
Ya. V. KOSHELYAEVA

The aim of this work was to define the features of the age structure of the silver birch stands in the Left-Bank Forest-Steppe considering forest site conditions, origin, site index and proportion of this species in the forest composition. Survival of silver birch in almost all age classes was the lowest in the relatively poor forest site conditions. The mean weighted age classes of silver birch are IV.8 in vegetative stands and IV.6 – in artificial seed stands. For all origins, the mean weighted age classes are V.1 for Sumy Region and IV.6 – for Kharkiv and Poltava Regions. The stands of the lower productivity have the least longevity. Survival of pure and almost pure stands (silver birch make 90 % of all the trees) is the lowest. At that, it is the highest in Sumy Region.


Sign in / Sign up

Export Citation Format

Share Document