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Tytuł:
Dynamics of non-structural carbohydrates in Pinus pallasiana D. Don needles under different forest growth conditions of ravine anti-erosion plantations
Autorzy:
Bessonova, V.
Yakovlieva-Nosar, S.
Powiązania:
https://bibliotekanauki.pl/articles/2106662.pdf
Data publikacji:
2022
Wydawca:
Instytut Badawczy Leśnictwa
Tematy:
ravine
man-made plantation
Crimean pine
Pinus pallasiana
forest
growth condition
sugar
starch
Opis:
The research was aimed at analysing the peculiarities of non-structural carbohydrate metabolism in the needles of Pinus pallasiana D. Don in anti-erosion plantations on the slope and in the thalweg of the Viyskovyi ravine under different forest growth conditions. The ravine is located in the Dnipropetrovsk region and belongs to the southern geographical variant of ravine forests. The studied plants grew at three experimental sites of man-made plantation: in the thalweg (forest growth conditions – mesophilic, fresh, CL2), in the middle part of the slope of the southern exposure (mesoxerophilic, somewhat dry, or semi-arid, CL1) and on the upper part of this slope (xerophilic, arid, CL0–1). Changes in glucose, fructose, reducing sugars, sucrose and starch during the period from May to October were studied. The concentration of osmotically active substances (glucose, sucrose) increases in the months with the most unfavourable hydrothermal parameters, especially in plants of mesoxerophilic and xerophilic forest growth conditions. The dynamics of fructose content revealed two maxima (July and October), when the concentration of glucose tends to increase steadily, with the highest values found in October. During the study period, the level of fructose in the needles under the arid conditions of the upper and middle parts of the slope was much lower than under the fresh conditions of the thalweg. The dynamics curve of the starch content tends to decrease from the maximum values in May to the first minimum in August. It is followed by some increase in the concentration of this polysaccharide that does not reach the previous values. The second minimum is registered in October. Such changes in the level of starch in the needles of plants are observed under all forest growth conditions. The decrease in polysaccharide content is consistent with the increase in glucose and sucrose, especially in August. A more significant increase in the concentration of soluble osmoprotective sugars (glucose, sucrose) in P. pallasiana needles under unfavourable hydrothermal conditions compared to normal moisture conditions indicates the ability of plants to adapt to mesoxerophilic and xerophilic conditions.
Źródło:
Folia Forestalia Polonica. Series A . Forestry; 2022, 64, 1; 38-48
0071-6677
Pojawia się w:
Folia Forestalia Polonica. Series A . Forestry
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hygrophilous old-growth forest lichens are highly capable of instantaneous photosynthesis activation after short-term desiccation stress
Autorzy:
Osyczka, P.
Powiązania:
https://bibliotekanauki.pl/articles/2142054.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
bioindicators
chlorophyll fluorescence
lichen ecophysiology
lichenized fungi
old-growth forest lichens
photosynthesis activation rate
lichen photobiont properties
Opis:
The vitality of lichens and their growth depend on the physiological status of both the fungal and algal partner. Many epiphytic lichens demonstrate high specificity to a habitat type and hygrophilous species are, as a rule, confined to close-to-natural forest complexes. Tolerance to desiccation stress and the rate of photosynthesis activation upon thallus hydration vary between species. Analyzes of chlorophyll fluorescence and photosynthesis efficiency have been widely applied to determine the viability of lichens. The aim of this study was to determine the activation photosynthesis rate upon hydration in epiphytic lichens exposed to short-term desiccation stress and to find potential links between their activation pattern and ecological properties. The results proved that even highly sensitive hygrophilous lichens, i.e., Cetrelia cetrarioides, Lobaria pulmonaria, Menegazzia terebrata, do not exhibit any delay in the restart of the photosynthesis process, compared to mesophytic or xerophytic ones. All examined lichens achieved nearly 100% of their maximum photosynthetic efficiency just one hour after they had been supplied with a relatively small quantity of water. Moreover, the increase in photosynthesis efficiency, measured at 20-minute intervals upon hydration, started from a relatively high level. In addition, the differences in the content of photosynthetic pigments and water holding capacity between species did not affect the general pattern of activation, which is comparable across various lichens. It can be concluded that healthy hygrophilous lichens do not require long hydration time to regain a high level of photosynthesis efficiency after a short rainless period. This fact supports the idea of applying chlorophyll fluorescence analysis in the field to assess vitality of lichens and the condition of their natural habitat.
Źródło:
Acta Biologica Cracoviensia. Series Botanica; 2022, 64, 1; 15-25
0001-5296
Pojawia się w:
Acta Biologica Cracoviensia. Series Botanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badania nad bonitacją drzewostanów w świetle literatury
Site index research: a literature review
Autorzy:
Kedziora, W.
Tomusiak, R.
Powiązania:
https://bibliotekanauki.pl/articles/2142721.pdf
Data publikacji:
2020
Wydawca:
Instytut Badawczy Leśnictwa
Tematy:
forest site index
tree growth
forest site quality
forest site productivity
wskaźnik bonitacji drzewostanów
wzrost drzew
jakość drzewostanów
produkcyjność drzewostanów
Opis:
the purpose of this paper was to review literature covering the topic of site index with particular emphasis on Scots pine, the most important forest-forming species in poland. we discuss the history of the site index, research on various tree species, statistical modelling methods, the spatial application of site index and age impact assessment. the history of research on the site index of forest species is long and dates back to the 18th century. Many researchers thought that determining the quality of the habitat is very important from the point of view of rational forest management. the site index, as a measure of the potential of the habitat on which the forest grows, is one of the most important characteristics of forest stands. the site index depends on the selected model, but is most often expressed as the average or top height of trees of a given species at a certain age. In our review, we point out several insufficiencies of studies on the site index, external influences and the connection of the site index with spatial conditions. Furthermore, research conducted so far has not explicitly confirmed that there is a relationship between the site index of pine stands and their geographical location in poland. More research on the site index, especially in regard with climate change, is needed.
Źródło:
Leśne Prace Badawcze; 2020, 81, 2
1732-9442
2082-8926
Pojawia się w:
Leśne Prace Badawcze
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Przestrzenna zmienność struktury drzewostanu w wybranych lasach o charakterze pierwotnym w Karpatach Zachodnich i Górach Dynarskich
Spatial variation in stand structure of selected old-growth forests in the Western Carpathians and the Dinaric Mountains
Autorzy:
Paluch, J.
Bartkowicz, L.
Powiązania:
https://bibliotekanauki.pl/articles/979198.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
lasy o charakterze pierwotnym
struktura drzewostanu
analiza porownawcza
Karpaty Zachodnie
rezerwat Oszast
rezerwat Perucica
Gory Dynarskie
leśnictwo
lasy góskie
pierśnicowe pole przekroju
zmienność przestrzenna
Beskid Żywiecki
rezerwat Żarnówka
old−growth forests
primeval forests
natural forest dynamics
structural heterogeneity
patch−mosaic
developmental stages
continuous cover forestry
Opis:
The research was conducted in three old−growth forests consisted of silver fir Abies alba Mill., European beech Fagus sylvatica L., and Norway spruce Picea abies Karst. located in the southern part of Poland (Żarnówka and Oszast) and the south−eastern Bosnia and Hercegovina (Perućica). The aim of the study was to compare basic stand characteristics and spatial heterogeneity in terms of variation in stand basal area and vertical structure. In each research area, small sample plots (0.015 ha) were localised in a regular 20×20 m grid covering approximately 10 ha. In each sample plot the diameter at breast height (d1.37 cm) and species of all live trees were recorded. For each plot the basal area of live trees and an index of structural diversification were determined. As a measure of structural diversification, the simple variance in tree height was computed and scaled through comparison with a hypothetical variance of the uniform distribution. The spatial patterns of basal area and structural diversification were tested with paired−plot approach. In addition, simulation techniques were used to model variation in the basal area of live trees dependent on spatial scale. The Carpathian and Dinaric stands considerably differed in basal area (ranging from 36.1 to 65.2 m2/ha) and volume (varying from 522 to 1176 m3/ha), but all of them had diameter distributions proximate to a negative exponential model. The basal area recorded on the 0.015 ha plots had a very similar pattern of variation, which could be generalised as a truncated normal distribution. The distribution of the structural diversification index was different and resembled an uniform (Perućica) or a bimodal distribution with modal values at its extremes (Oszast and Żarnówka). However, in the spatial scales above 1,000 m2 the index distri− bution become similar to a normal (Oszast) or a truncated normal (Perućica and Żarnówka) ones with high mean values, indicating the predominance of complex vertical structures. In general, the spatial variability in basal area and structural diversification of live trees tended to be random. These results suggest that the patch−mosaic assumption being fundamental for the developmental cycle hypothesis is inapplicable to the studied primeval forests. Regardless of differences in geographic location and site conditions, the studied stands show a similar spatial pattern of structural heterogeneity, suggesting a close resemblance of disturbance regimes driving its dynamics.
Źródło:
Sylwan; 2020, 164, 02; 91-101
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Struktura i dynamika wielogeneracyjnych starodrzewów sosnowych występujących w obszarach ochrony ścisłej Kaliszki i Sieraków w Kampinoskim Parku Narodowym. Część 1. Zróżnicowanie gatunkowe, zagęszczenie i pierśnicowe pole przekroju
Structure and dynamics of uneven−aged Scots pine−dominated old−growth stands in Kaliszki and Sieraków strict protection areas in the Kampinos National Park. Part 1. Species composition, tree density and basal area
Autorzy:
Brzeziecki, B.
Zajączkowski, J.
Olszewski, A.
Bolibok, L.
Andrzejczyk, T.
Bielak, K.
Buraczyk, W.
Drozdowski, S.
Gawron, L.
Jastrzębowski, S.
Szeligowski, H.
Żybura, H.
Powiązania:
https://bibliotekanauki.pl/articles/978936.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
forest dynamics
long−term research
old−growth forest
permanent study plot
strict protection
tree
species composition
Opis:
The paper describes changes, which took place over the last 30 years in old−growth forest stands occupying two permanent research plots, established in the Kaliszki and Sieraków strict protection areas in the Kampinos National Park (central Poland). Both plots have a form of ecological transects. The Kaliszki plot is 20 m wide and 700 m long (1.40 ha), while the Sieraków plot (total area of 2.56 ha) consists of two parts: main (40×460 m) and side (40×180 m) transect. In the Kaliszki plot, the stand measurements were conducted in 1993, 2007, and 2017, while in the Sieraków plot – in 1989, 1994, 2006, and 2017. For every tree with breast height diameter (DBH) 5 cm, species identity, DBH and spatial coordinates were determined. Starting from the second census, all trees which had died (‘losses’), as well as trees which exceeded the DBH threshold (‘gains’) since the previous record were noted, as well. The major tree species occurring on sample plots are Scots pine (Pinus sylvestris), pedunculate oak (Quercus robur), silver and downy birch (Betula sp.), and black alder (Alnus glutinosa). During the study period, the overall tree density declined by ca. 50%. The diminishing trends occurred for all dominant tree species. In contrast to major, dominant tree species, the demographic status of a group of minor tree species (lime, hornbeam and maple) was much more stable. One may even speak about some expansion in this case. Particularly, hornbeam density increased rapidly in the period 2006−2017 in some areas of the main transect located in the Sieraków plot. The future studies will show if this tendency will be maintained and will include other regions of sample plots. Assuming a lack of significant disturbances, one may expect that the stands growing on research plots will rather slowly change in the nearest future. Most dynamics will have a quantitative and not qualitative character. One may anticipate, for example, a growing role of pedunculate oak at the expense of Scots pine, however, considering that the two species are rather long−living, they will probably for a long time keep their dominant roles in the stand canopies.
Źródło:
Sylwan; 2020, 164, 05; 392-403
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Struktura i dynamika wielogeneracyjnych starodrzewów sosnowych występujących w obszarach ochrony ścisłej Kaliszki i Sieraków w Kampinoskim Parku Narodowym. Część 2. Procesy zamierania i dorastania oraz ich wpływ na rozkład grubości drzew
Structure and dynamics of uneven−aged, Scots pine−dominated, old−growth stands in Kaliszki and Sieraków strict reserves in Kampinos National Park. Part 2. Tree mortality and recruitment processes and their effects on tree diameter distributions
Autorzy:
Brzeziecki, B.
Zajączkowski, J.
Olszewski, A.
Bolibok, L.
Andrzejczyk, T.
Bielak, K.
Buraczyk, W.
Drozdowski, S.
Gawron, L.
Jastrzębowski, S.
Szeligowski, H.
Żybura, H.
Powiązania:
https://bibliotekanauki.pl/articles/979128.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
demographic non−equilibrium
diameter structure
long−term study
old−growth forest
permanent study
plot
scots pine
strict protection
Opis:
Two fundamental demographic processes (tree recruitment and mortality) are analyzed for forest stands growing on permanent study plots located in strictly protected Scots pine−dominated, old−growth stands of Kampinos National Park (central Poland). The major implications of the observed demographic trends for the general shape of tree size distributions are determined, as well. During the past ca 30 years, in the stands sampled, there was a pronounced lack of balance between mortality and recruitment processes. Mortality rate was eight times higher than recruitment rate. Eventually, there was a net significant decline in population density, observed for all major tree species, including Scots pine, pedunculate oak, silver and downy birch, and black alder. As mortality processes affected mainly smaller trees, there was also a significant deterioration of the general demographic status of most important tree species. This effect was shown by the change of the overall shape of diameter distributions over the study period: from reverse J−shaped to flat curves running nearly parallel to X−axis. The values of recruitment rates were markedly lower, and the values of mortality rates – significantly higher, than analogous values characterizing comparable forests (e.g., those obtained for the natural stands of Białowieża National Park). Low recruitment rates, as obtained for Kampinos stands, suggest that presently, in the local, Scots pine−dominated, old−growth stands, the general conditions for forest regeneration and for maintaining a long−term demographic stability are unfavorable. Most probably, the regeneration of this type of forest has an episodic, ‘wave−like’ character and corresponds to the ‘catastrophic’ model, according to which the successful regeneration of current dominants (especially Scots pine, silver and downy birch, black alder) must be preceded by a stand−initiating (stand−replacing) disturbance, leading to total or partial, but heavy, destruction of the currently existing stand. At the moment, it would be difficult to predict, however, if and when such a disturbance will affect the stands under investigation. Thus, we predict that in the nearest future at least, the state of overall demographic unbalance will continue or even increase.
Źródło:
Sylwan; 2020, 164, 06; 443-453
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effect of Irrigation on the Annual Apical Growth of the12-14 Years Old Seed Plants of Black Saksaul
Autorzy:
Dosmanbetov, Daniyar
Maisupova, Bagila
Abaeva, Kurmankul
Mambetov, Bulkair
Akhmetov, Ruslan
Powiązania:
https://bibliotekanauki.pl/articles/125192.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
Black saksaul
forest growth conditions
soil profile
soil
laboratory analysis
annual apical growth
Opis:
This article discusses the ways of solving the problems of fruiting and increasing the yields, as well as obtaining high-quality standard seeds from promising seed plants of black saksaul (Haloxylon aphyllum (Minkw.) Iljin). It presents the results of studying the effect of irrigation and the use of fertilizers on the annual growth of the apical shoots of saksaul, and the effect of irrigation on the further stability of seed plants fruiting for sustainable seed supply for reproduction of saksaul deserts and forest amelioration of deserts. The morphological description of the soil by profiles has been given, and the effect of irrigation on the soils of the type II forest conditions has been described. This study was aimed at resolving the problem of fruiting frequency, increasing the yield and quality of promising black saksaul seed plants by determining the moisture dynamics in the one-meter thick soil layer under saksaul specimens for determining the methods, norms, and time of irrigating seed plants. Long-term observations show that well-developed specimens of black saksaul have appeared in the last 15-20 years on the roadside in some settlements, e.g., Bakbakty, Bakanas, Akkol, Koktal, Karoy, the motor road in village Kanshengel, Topar, Araltobe, Akzhar in the Almaty area, which passes through natural saksaul plantings and the soil with the formation of layered clay, sandy loam, and crushed stone. On the one hand, this was promoted by the presence of layered and well-aerated roadsides of the bulk roadbed, and on the other hand, by additional wetting from the runoff of precipitation from the asphalt pavement.Naturally, these saksaul plantings growing along the roads alone or in rows give a good yield when fruiting; seed plants may also be identified in these groups.
Źródło:
Journal of Ecological Engineering; 2020, 21, 4; 11-18
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zmiany bogactwa gatunkowego runa borów sosnowych na pasach wydmowych Kampinoskiego Parku Narodowego na początku XXI wieku
Changes of the herb layer species richness within Scots pine forest of the dune belts in the Kampinos National Park (central Poland) at the beginning of XXI century
Autorzy:
Zaniewski, P.T.
Solon, J.
Ferchmin, M.
Siedlecki, L.
Powiązania:
https://bibliotekanauki.pl/articles/979033.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
peucedano−pinetum
querco−pinetum
permanent plots
semi−permanent plots
old−growth pine forest
fluctuation
species richness decrease
Opis:
Scots pine forest are of the main economic importance to the forest management in lowland Europe. Large areas of spontaneous pine forest, including old−growths, are located on two vast dune belts of the Kampinos National Park (central Poland). These forests grow on oligotrophic sandy soils with deep groundwater level. This makes the area unique to study long−term changes in this type of pine forest communities. The aim of the work was to assess the changes in the species composition and richness of undergrowth of Scots pine forests at the beginning of the XXI century. The study was conducted on 10 permanent and 53 semi−permanent plots located within stands of Peucedano−Pinetum and Querco−Pinetum associations on both dune belts of Kampinos National Park. The fieldworks were performed in 2001 and 2002, and repeated in 2015 and 2018. Based on Ward’s cluster analysis we described five local forms of plant communities. Seven species groups were distinguished and changes in their richness assessed using one sample Wilcoxon test. Each species group included species characteristic and/or differentiating for a given set of syntaxonomical units. The results confirmed the hypothesis of gradual decrease of the total species richness. The median of species richness change was –0.308 species per year and was statistically significant. The changes were bigger within the local forms of the Querco−Pinetum association in comparison to Peucedano−Pinetum. The decrease was connected especially with dry grassland and heathland species (characteristic for syntaxons of Koelerio−Corynephoretea and Nardo−Callunetea classes) as well as with coniferous forest generalist species (characteristic for syntaxons of Vaccinio−Piceetea and Cladonio−Vaccinietalia). The results suggest that the two main processes shaping the species composition at the beginning of XXI century within pine forest located on the dune belts of Kampinos National Park may be identified as (i) fluctuation, and (ii) simplification, manifested by species richness decrease. This is probably connected with forest regeneration after past human use and disturbance.
Źródło:
Sylwan; 2020, 164, 04; 331-342
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimating the growth of 20- to 26-year-old lodgepole pine plantations in the Leningrad region of Russia
Autorzy:
Zhigunov, Anatoly V.
Butenko, Оlesia Y.
Powiązania:
https://bibliotekanauki.pl/articles/2044167.pdf
Data publikacji:
2019
Wydawca:
Instytut Badawczy Leśnictwa
Tematy:
introduction
lodgepole pine
forest plantations
growth
standing crop
Opis:
The aim of our study was to compare the growth rates of lodgepole pine (Pinus contorta Dougl.) with those of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies L.) in plantations. The experimental plots were established in 1988, 1989 and 1994 in the southern part of the Leningrad region. In 2014, the condition of the plants on those plots was examined and their linear parameters were measured. The comparison of Scots pine with lodgepole pine of the same age growing in similar soil conditions has shown that Scots pine has only an insignificant advantage over lodgepole pine in the growth rate. In the mixes of Norway spruce and lodgepole pine, Norway spruce considerably suppresses the growth of lodgepole pine. Lodgepole pine has successfully adapted to the climatic conditions of the Leningrad region of Russia, which is easy to see from the well-preserved plantations and their annual bearing. No significant damage because of either diseases or insect pests has been revealed. It is for the first time that the volume yield of lodgepole pine was determined in 20- to 26-year-old experimental plantations in the Leningrad region of Russia.
Źródło:
Folia Forestalia Polonica. Series A . Forestry; 2019, 61, 1; 58-63
0071-6677
Pojawia się w:
Folia Forestalia Polonica. Series A . Forestry
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Porównanie odnowień sosny zwyczajnej powstałych z siewu i sadzenia w różnych terminach
Comparing Scots pine regeneration established by sowing and planting at various times of year
Autorzy:
Barzdajn, W.
Kowalkowski, W.
Tomczak, R.
Powiązania:
https://bibliotekanauki.pl/articles/1290847.pdf
Data publikacji:
2019
Wydawca:
Instytut Badawczy Leśnictwa
Tematy:
lesnictwo
hodowla lasu
odnowienia lasu
drzewa lesne
sosna zwyczajna
Pinus sylvestris
odnowienia z siewu
odnowienia przez sadzenie
wzrost roslin
zageszczenie roslin
methods of forest regeneration
pine growth
density
Opis:
The aim of this study was to evaluate the practical feasibility of two forest regeneration methods using Scots pine Pinus sylvestris L. To this end, comparative experiments were established in the Złotoryja and Legnica Forest Districts. The site in Złotoryja had been clear cut, while the experimental plot in Legnica was established at a location damaged by wind in 2009 and cleared from wind throws and wind-broken trees before the experiment. Four different dates for sowing and two for planting were chosen in order to investigate the potential forest regeneration with respect to time. Both experiments were established according to the same design: a complete random block design with five replication blocks. To each plot we applied approximately 53 g (1.2 kg/ha) of seeds and planted 230 seedlings (10 200 seedlings/ha). In 2017, the height of the pine trees was recorded and their increment in height was measured in 2016 as well as 2017. A preliminary analysis of results was conducted using ANOVA for multiple experiments in order to identify significant differences and to then combine variables to form homogeneous groups to which the Duncan multiple range test could be applied. For growth traits, the ANOVA showed significant differences between experimental sights as well as a significant interaction of factors with the experimental site. In terms of planting, April was the most advantageous resulting in the greatest tree height in both forest districts, while in the Legnica Forest District the saplings planted in April also showed the greatest annual increments. Among the sowing dates, the most advantageous was the winter sowing, while the April sowing date produced the least desirable results. In conclusion, both sowing and planting are effective methods to establish pine cultures in coniferous forest. Furthermore, both methods may be performed at the currently recommended spring date, but they may also be postponed to summer and winter dates provided favorable weather conditions prevail.
Źródło:
Leśne Prace Badawcze; 2019, 80, 3
1732-9442
2082-8926
Pojawia się w:
Leśne Prace Badawcze
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effects of Forests on Economic Growth in Nigeria (1990 – 2015)
Autorzy:
Oyetunji, P. O.
Powiązania:
https://bibliotekanauki.pl/articles/1077356.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Forestry
economic growth
ecotourism
forests
ustainable use of forest resources
Opis:
This study empirically examines the impact of forests on economic growth in Nigeria for the period of 1990 to 2015. Unit root tests were carried out using the Augmented Dickey Fuller (ADF) test, while the Bounds cointegration test was used to establish a long run relationship between the forests and other independent variables and economic growth. An Error Correction Model (ECM) was also employed to determine the nature of the long run relationship. The findings show that forests have a positive effect on economic growth, however, this is not statistically significant. This study recommends that the government should intensify its efforts in the forestry sector so as to improve the productivity of forest resources in Nigeria. Moreover, the Nigerian government should discourage illegal felling of trees and the importation of timber products, as well as engage and develop the rural communities to reduce the pressure on forest resources and ensure sustainable use. The study also recommends the sustainable use of forest resources through ecotourism and the development of the forestry value chain in Nigeria.
Źródło:
World News of Natural Sciences; 2019, 23; 254-265
2543-5426
Pojawia się w:
World News of Natural Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamika rozpadu drzewostanów świerkowych w Beskidzie Śląskim
Decline of Norway spruce stands in the Beskid Slaski Mts.
Autorzy:
Dmyterko, E.
Bruchwald, A.
Powiązania:
https://bibliotekanauki.pl/articles/986624.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
Beskid Slaski
drzewostany swierkowe
zamieranie drzew
swierk pospolity
Picea abies
rozpad drzewostanow
System Informatyczny Lasow Panstwowych
model wzrostu drzewostanu
rozmiar uzytkowania rebnego
zagrozenia lasu
szkody od wiatru
modele ryzyka uszkodzenia
Nadlesnictwo Wisla
Nadlesnictwo Wegierska Gorka
Nadlesnictwo Ustron
Nadlesnictwo Bielsko
forest decline
picea abies
stand growth model
harvest volume model
wind damage risk model
forest
threat measure
Opis:
The dynamics of decline of Norway spruce forests in the Beskid Śląski Mts. (S Poland) in a 2007−2016 period was analysed based on data from the State Forests Information System. For that purpose we used modified growth model and wind damage risk model. The harvested timber volume (salvage cuts) exceeded the allowable harvest modeled with the stand growth model by 270% in years 2007−2010 (earlier period) and by 89% in the 2011−2016 (later period) period. The highest volume exceed (503 and 307% for earlier and later period respectively) was recorded for the Wisła Forest District. For the deadwood, the harvested volume exceeded the modeled one by 45% (162 in earlier, and 59% in later period). In the Węgierska Górka Forest District the harvested volume amounted to 287% of the modeled one (438 in earlier, and 70% in later period). The largest amount of wind−broken and wind−fallen trees was found in Wisła. Their volume amounted to 48% of the modeled volume (59 in earlier, and 40% in later period). The highest exceed occurred in Węgierska Górka (89 and 70% in the later period respectively). The species composition in the analysed region changed significantly as the share of spruce decreased and share of beech and fir increased (tab. 1). Changes in the aeral fraction of stands in age classes in the Bielsko and Ustroń forest districts were insignificant (tab. 2). For Węgierska Górka, share of stands in age class <20 years increased from 11 to 40%, while the older stands fraction decreased. Major changes occurred in Węgierska Górka and Wisła as far as structure of the stands in the risk damage factor classes is concerned. Fraction for the risk factor classes I and II increased, while for class VI decreased (tab. 3, fig. 4). The highest dynamics of the wind threat measure was recorded especially in Węgierska Górka, where its value decreased from 42 in 2009 to 19 in 2016 (fig. 5). The biggest changes are likely to occur in Wisła in the next years due to the very high fraction of spruce. A significant damage caused by wind may also be expected in Ustroń, where the threat measure is high.
Źródło:
Sylwan; 2018, 162, 03; 189-199
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of forest growth conditions on the wood density: the case of Amur Region
Autorzy:
Romanova, Natalia A.
Zbirnov, Alexander B.
Yust, Natalia A.
Fucheng, Xu
Powiązania:
https://bibliotekanauki.pl/articles/2045741.pdf
Data publikacji:
2018
Wydawca:
Instytut Badawczy Leśnictwa
Tematy:
forest growth conditions of the Amur region
Amur region
wood density
Dahurian larch
Scots pine
wood moisture content
Asian white birch
Opis:
The problem of determining the dependence of the chainsaw on the density of wood, substantiation of effective options for the number of chainsaws in the assortment and whiplash method of logging is quite relevant. In the Far East of Russia, in particular, in the Amur region, the forest growth conditions are different from the western ones, and therefore, the properties of the wood differ from the generally accepted ones. The article describes forest growth conditions that influence the properties of the wood in areas of the Amur region. Using the method of density determination, the density of larch, pine and birch were studied for first time in the areas of the region. The dependence of the density on humidity, age, species, season of the year and the area of growth was found out. The results of the research showed that under humidity of 70%, the density of larch was 1088.99 kg/m3, it was 919.8 kg/m3 for pine and it was for birch 915.9 kg/m3.
Źródło:
Folia Forestalia Polonica. Series A . Forestry; 2018, 60, 4; 292-298
0071-6677
Pojawia się w:
Folia Forestalia Polonica. Series A . Forestry
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Measurement and evaluation of timber yields and corresponding non-timber forest products of selected tree species. An exploratory study on poplar, Acacia, Ulmus and Juglans tree species in Kyrgyzstan
Autorzy:
Agbenowu, Y.I.S.
Attah, R.
Powiązania:
https://bibliotekanauki.pl/articles/2049706.pdf
Data publikacji:
2018
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
forest zone
Kirgizstan
timber yield
wood measurement
evaluation
poplar
Acacia
Ulmus
Juglans
biomass
volume
net present value
growth yield
rotation age
Opis:
With issues of high timber demand and illegal logging in the forest zones of Kyrgyzstan, agroforestry may serve as a viable option for rectification. Yields of timber and expected income from the most popular tree species are in most cases lacking. The goal of this study is to evaluate the timber yields and non-timber forest product from Ulmus, Poplar, Acacia and Juglans tree species in Kyrgyzstan. More focus was allocated to Poplar as this is one of the most common and preferred tree species in Kyrgyzstan. A sample size of 420 trees was recorded from 18 stands with 20 trees measured in each stand with the exception of Juglans which were 6 stands with 9-17 trees each The study estimated (i) tree volume using allometric parameters (ii) age-biomass relationship (iii) Factual Branch Analysis model to estimate the above ground biomass of the different tree segments (iii) revenue deduction and NPV of Poplar trees and (iv) biological rotation Age to determine the suitable age for Poplar harvesting. The findings show that NPV is highest at 10 years for Poplar when it is being considered for fast-growing timber. The biological rotation age was, however, higher at around 17 years. Site-specific age-biomass model appears to be suitable for estimating tree biomass since the tree allometry was found to differ significantly between studied stands even with similar age ranges. The developed relationship and tree database can adequately be applied to estimate tree volume and biomass in similar site conditions in the studied region.
Źródło:
Environment, Earth and Ecology; 2018, 2, 1; 12-27
2543-9774
2451-4225
Pojawia się w:
Environment, Earth and Ecology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zmiany zachodzące w drzewostanach Bieszczadów
Changes in the forests of the Bieszczady Mts.
Autorzy:
Dmyterko, E.
Bruchwald, A.
Powiązania:
https://bibliotekanauki.pl/articles/985915.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
lasy gorskie
Bieszczady
drzewostany
sklad gatunkowy
zmiany w drzewostanach
zmiany skladu gatunkowego
model wzrostu drzewostanu
modele ryzyka uszkodzenia
species composition
stand growth model
model allowable cut
wind damage risk model
forest threat
measure
Opis:
The aim of the study was to analyse (on the basis of the data from the State Forests Information System) the changes occurring in the Bieszczady forests in the period of 2007−2016. One of the processes taking place in the study area is the withdrawal of grey alder stands and the appear− ance of natural regeneration of mainly beech and fir, and in a smaller proportion spruce (fig. 1). Another natural process is the encroachment of fir and beech under the canopy of pine stands, which is favoured by fertile habitats that meet the ecological requirements of these two tree species. As a result of economic activity supporting these processes, alder and pine stands are being rebuilt relatively quickly, turning into fir or beech stands, and sometimes into mixed stands with the participation of other tree species, including spruce (fig. 1). The decline of spruce stands occurs on the dominant area in Poland: in Beskid Śląski and Beskid Żywiecki, the Kaszuby Forest or the Białowieża Forest. The main causes of this process are abiotic and biotic factors, including frequent droughts causing the lowering of the groundwater level and insect outbreaks, especially of bark beetles. The proportion of spruce in the Bieszczady Mountains is relatively small (about 10%), and the high fertility of the habitats compensates, to some extent, the relatively high moisture requirements of this tree species and probably these factors determined the lack of decline of spruce stands in the analysed area. In the last 10 years, the average age of forests in the Bieszczady Mountains increased from 77 to 83 years (tab. 2), mainly as a result of too low volume of harvested timber (fig. 3). Comparing the total harvested volume with the volume of allowable cut determined by the stand growth model, the harvest of the wood raw material was understated by about 25%. The aging of forests is also confirmed by changes in stands in age classes (fig. 2). The aging of the Bieszczady forests is correlated with the process of increasing the threat to these forests by wind (figs. 4−5). The wind damage risk factor increased over the next 10 years in the two highest threat level, and thus the area of threatened stands increased. The forest threat measure in the Bieszczady forests increased in general as well as in individual forest districts (fig. 6). The forests in two of these districts are currently among the most threatened in Poland.
Źródło:
Sylwan; 2018, 162, 05; 355-364
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
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