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Tytuł:
Wpływ cech populacji i środowiska na dokładność i precyzję wyników symulacji lotniczej inwentaryzacji zwierzyny
Effects of population and habitat characteristics on the accuracy and precision of wildlife aerial surveys results
Autorzy:
Witczuk, J.
Pagacz, S.
Powiązania:
https://bibliotekanauki.pl/articles/979294.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
bias
drone
simulations
thermal infrared
variability
wildlife monitoring
Opis:
Estimation of population abundance is one of the most difficult tasks in wildlife management. In case of forest−dwelling ungulates, none of the currently available survey methods is satisfying in terms of accuracy, precision, and cost−effectiveness. Therefore, we propose a new method of ungulate monitoring based on distance sampling and using unmanned aerial vehicles equipped with thermal infrared cameras. The method is potentially more reliable and cost−effective than conventional survey techniques. It also allows for aerial surveys in the dark when animals are most active. However, the method needs to be tested before wide−scale implementation in wildlife management practice. While the effects of sampling design and effort on accuracy and precision of abundance estimates are well recognized, the importance of population and habitat characteristics is often overlooked by wildlife managers. We used simulations to assess the effects of population size, animal aggregation, and habitat−depended detection probability on the accuracy and precision of wildlife aerial survey results. We created 1000 virtual populations defined by population density (2−22 individuals/100 ha), mean group size (1−6 individuals), and probability of animal detection during surveys (proportional to canopy cover, 30−60%). Animals were distributed on a virtual study area (5000 ha) according to randomly generated density distribution. Each population was subjected to 25 simulated surveys using the same design (39 transects grouped in three 2.0×2.5 km blocks). The transects covered 12% of the entire study area. We used conventional distance sampling to estimate abundance and generalized linear models to assess the effect of each parameter on the accuracy and precision of estimates. The estimation accuracy was mostly affected by the probability of detection (B=–0.75) and, to a lesser degree, by aggre− gation (B=–0.25) and population size (B=0.09). Precision was influenced by the aggregation (B=0.32) and population size (B=–0.26), while detection probability had a weaker effect (B=–0.11). Observed significant differences in quality of abundance estimates derived by the same survey design, but with differing population and habitat characteristics, indicate that each survey requires an individual approach. It is impossible to formulate general recommendations, e.g. concerning flight plan or area coverage. To achieve the required level of precision, while minimizing the survey costs, it is necessary to test alternative survey designs with the aid of computer simulations.
Źródło:
Sylwan; 2020, 164, 07; 560-567
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Inwentaryzacja zasobów drzewnych w urządzaniu lasu w Polsce
Inventory of timber resources in forest management in Poland
Autorzy:
Jaszczak, R.
Powiązania:
https://bibliotekanauki.pl/articles/1015664.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
inwentaryzacja
Polska
zasoby drzewne
lesnictwo
urzadzanie lasu
quercus robur
pedunculate oak
variability
heritability
Opis:
The paper presents the comparison of heritability of height and diameter at breast height (dbh) in 7−11− year−old pedunculate oak trees from 5 provenances and 55 families. The provenance heritability for five successive years was high: 0.19−0.80 for height and 0.59−0.87 for dbh. Family heritability was moderate ranging 0.39−0.52 for height and 0.34−0.49 for dbh, while individual−tree heritability values was the lowest equalling 0.08−0.15 for height and 0.06−0.14 for dbh.
Źródło:
Sylwan; 2008, 152, 05; 14-25
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zróżnicowanie morfologiczne szyszek daglezji zielonej (Pseudotsuga menziesii [Mirb.] Franco) w Polsce
Morphological differentiation of Douglas fir (Pseudotsuga menziesii [Mirb.] Franco) cones in Poland
Autorzy:
Klimko, M.
Zygmunt, K.
Powiązania:
https://bibliotekanauki.pl/articles/1035852.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
szyszki
Pseudotsuga menziesii
botanika lesna
daglezja zielona
lesnictwo
zroznicowanie morfologiczne
drzewa lesne
pseudotsuga menziesii
variability
cones
Opis:
The paper presents results of studies on population variability of Douglas fir (Pseudotsuga menziesii [Mirb.] Franco) cones. The studies were based on statistical analysis of cone morphological characteristics, seed scales and bract of populations originating from 12 sites. The analysis proved morphological variability of cones and scales. They did not show geographical variation and did not clearly confirm their demographic variation. The edaphic conditions and genetic diversity were found to affect the demonstrated variability.
Źródło:
Sylwan; 2003, 147, 10; 54-65
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wieloletnia zmienność temperatury powietrza i opadów atmosferycznych w Puszczy Zielonka
Long-term variability of air temperature and precipitation in Puszcza Zielonka Forest
Autorzy:
Okoński, B.
Miler, A.T.
Powiązania:
https://bibliotekanauki.pl/articles/996029.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
Puszcza Zielonka
warunki klimatyczne
temperatura powietrza
opady atmosferyczne
zmiennosc czasowa
puszcza zielonka forest
variability
air temperature
precipitation
Opis:
Puszcza Zielonka Forest is located in the central part of the Warta river basin, in the middle of Wielkopolska region on a plateau covered by deep morain or zander sand and gravel (over 90%). Fresh habitats dominate (95%) and the groundwater level depth is below the range of tree roots reach over ca. 80% of the area. The paper discuses variability of precipitation and temperature in Puszcza Zielonka for the period 1848−2008 with the assessment of water availability for forest environment.
Źródło:
Sylwan; 2012, 156, 06; 473-480
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badania nad zmiennością genetyczną w naturalnie odnawiających się populacjach daglezji zielonej (Pseudotsuga menziesii (Mirb.) Franco)
Genetic variability of naturally regenerated populations of Douglas fir (Pseudotsuga menziesii (Mirb.) Franco)
Autorzy:
Zygmunt, K.
Klimko, M.
Powiązania:
https://bibliotekanauki.pl/articles/1024054.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
Pseudotsuga menziesii
markery genetyczne
zmiennosc genetyczna
izoenzymy
botanika lesna
daglezja zielona
lesnictwo
drzewa lesne
pseudotsuga menziesii
genetic variability
isoenzymes
Opis:
Genetic variability of Douglas fir was studied in seven naturally regenerated populations. The genetic structure of the self−sown young generation was described by means of variability of eight enzymes (Dia, G−6−pd, Got, Idh, Pgi, Pgm, Sdh and Shdh) separated electrophoretically on a starch gel. The results indicate that no substantial reduction of the genetic pool and no substantial inbreeding effect were observed in naturally regenerated Polish populations of this introduced species.
Źródło:
Sylwan; 2004, 148, 09; 43-54
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wyniki 35-letniego doświadczenia proweniencyjnego z sosną zwyczajną z serii IUFRO 1982 na powierzchniach w Wyszkowie i Sękocinie
Result of the 35 years provenance experiment with Scots pine from the IUFRO 1982 series on the trials in Wyszkow and Sekocin
Autorzy:
Kowalczyk, J.
Wojda, T.
Powiązania:
https://bibliotekanauki.pl/articles/980212.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
hodowla lasu
drzewa lesne
sosna zwyczajna
Pinus sylvestris
doswiadczenia proweniencyjne
IUFRO
provenace variability
iufro 1982 trail
forest tree breeding
Opis:
Scots pine is the main forest tree species in Poland. In this study we investigated variation in growth among 20 populations at two common−garden sites of the IUFRO 1982 provenance experimental series after 35 years of growth. The sites managed by the Forest Research Institute are located in Wyszków and Sękocin (central Poland). Populations show great diversity in the productivity and stem straightness depending on the geographical origin. The character of variability confirms the results obtained on other experimental plots established within the IUFRO 1982 series. In terms of growth, populations such as: Pornóapáti, Ardennes, Haguenau, Neuhaus as well as Miłomłyn, Rychtal and Bolewice are the best. Populations from the south of Europe grow in Polish conditions very poorly and have a low survival rate. Some of the well−growing populations (Ardennes, Pornóapáti and Haguenau) probably comes from selected stands or seed orchard. Stabilization of ranging for the best and worst populations can be observed after 15 years of growth (fig. 1). It follows that in growing experiments, conclusions about the breeding value can be drawn after 15 years. Polish populations such as Miłomłyn, Rychtal and Bolewice are growing very well and can be the basis for further selection work. Obtained results can be used for future breeding, forest genetic resources conservation and also for the other research like dendrochronology and better estimation of the seed transfer rules of forest reproductive material.
Źródło:
Sylwan; 2019, 163, 07; 584-589
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ stosowanych zabiegów pielęgnacyjnych i rębni na zmianę struktury genetycznej drzewostanów
The effect of tending treatments and cutting systems on the genetic structure of stands
Autorzy:
Sabor, J.
Powiązania:
https://bibliotekanauki.pl/articles/1026480.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
oddzialywanie na las
drzewostany
rebnie
selekcja naturalna
lesnictwo
zmiany struktury genetycznej
zabiegi pielegnacyjne
genetic variability
silvicultural treatments
natural selection
heterozygousness
mating
forest sustainability
Opis:
Modern forestry puts effect to ensure the genetic and ecosystemic variability. The paper points to the role of natural selection and maintenance of forest sustainability and provides the characteristic of stands as genetic population and the description of mating systems and their impact on the heterozygous level in trees, as well as of the mechanism of the gene transfer. This is the background to determine genetic effects of the selection and tending treatment such as grading of seeds and seedlings, early and late cleaning, thinning and final felling on forest cultivation.
Źródło:
Sylwan; 2003, 147, 02; 39-48
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polimorfizm izoenzymów świerka pospolitego rasy istebniańskiej, tarnawskiej oraz wybranych pochodzeń doświadczenia IPTNS-IUFRO 1964/68 w Krynicy
Isoenzyme polymorphism of Norway spruce of the Istebna and Tarnawa race and selected provenances tested in IPTNS-IUFRO 1964/68 trial in Krynica
Autorzy:
Masternak, K.
Polak-Berecka, M.
Powiązania:
https://bibliotekanauki.pl/articles/989975.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
drzewa lesne
swierk pospolity
Picea abies
swierk istebnianski
swierk tarnawski
izoenzymy
zmiennosc genetyczna
doswiadczenia proweniencyjne
IUFRO
picea abies
iufro
isoenzymes
genetic variability
Opis:
In this study the genetic structure of Istebna and Tarnawa plus trees was studied and polymorphism of twenty four provenances of spruce tested in a IPTNS−IUFRO 1964/68 site in Krynica representing selected regions of the species occurrence was analyzed. The genetic diversity was estimated with seven isoenzyme systems encoded in eleven loci. The highest genetic polymorphism was shown by plus trees of the Istebna and Tarnawa race and the lowest by spruce from IUFRO experiment. There was a statistically significant effect of origin on the mean number of alleles per locus. The origin of the analyzed trees had no effect on other parameters of genetic variability: the effective number of alleles per locus, observed and expected heterozygosity and Wright index.
Źródło:
Sylwan; 2014, 158, 07; 516-523
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ skały macierzystej na przestrzenne zróżnicowanie zasobów węgla organicznego w glebach leśnych
Influence of parent material on the spatial distribution of organic carbon stock in the forest soils
Autorzy:
Gruba, P.
Socha, J.
Blońska, E.
Lasota, J.
Suchanek, A.
Gołąb, P.
Powiązania:
https://bibliotekanauki.pl/articles/990992.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
gleboznawstwo lesne
gleby lesne
wegiel organiczny
zroznicowanie przestrzenne
drzewostany
sklad gatunkowy
uziarnienie gleby
skaly macierzyste
carbon sequestration
spatial variability
species composition
soil properties
Opis:
The study focused on the influence of several soil properties and forest species composition on spatial distribution of organic carbon stock in soils developed from the contrasted parent materials: Tertiary claystones and sandstones, and Qurternary sands of different origins. Soil sampling was performed on 110 plots, while forest mensuration was conducted on 82 ones. The content of <0.05 mm fraction determined by the type of parent material played a key role in the distribution of carbon stock in soils. Higher content of fine fraction favoured the accumulation in mineral part of soil, while higher sand content had an indirect influence on accumulation of carbon in the organic horizon. Forest species composition and biomass volume are more important for C accumulation in the O horizons. Taking into account the geological heterogeneity, the size of investigation area played a prominent role for the statistical significance of the observed correlations between carbon stocks and the other soil properties.
Źródło:
Sylwan; 2014, 158, 06; 443-452
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Porównanie odziedziczalności proweniencyjnej, rodowej i indywidualnej cech wzrostowych dębu szypułkowego (Quercus robur L.) w doświadczeniu rodowo−proweniencyjnym w Nadleśnictwie Milicz
Comparison of provenance, family and individual heritability of growth traits in pedunculate oak [Quercus robur] in the family-provenance trial in the Milicz Forest District
Autorzy:
Barzdajn, W.
Powiązania:
https://bibliotekanauki.pl/articles/1015662.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
odziedziczalnosc
zmiennosc cech
wzrost roslin
rody hodowlane
proweniencje
wysokosc drzew
Quercus robur
lesnictwo
piersnice drzew
dab szypulkowy
drzewa lesne
quercus robur
pedunculate oak
variability
heritability
Opis:
The paper presents the comparison of heritability of height and diameter at breast height (dbh) in 7−11− year−old pedunculate oak trees from 5 provenances and 55 families. The provenance heritability for five successive years was high: 0.19−0.80 for height and 0.59−0.87 for dbh. Family heritability was moderate ranging 0.39−0.52 for height and 0.34−0.49 for dbh, while individual−tree heritability values was the lowest equalling 0.08−0.15 for height and 0.06−0.14 for dbh.
Źródło:
Sylwan; 2008, 152, 05; 52-59
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rozmieszczenie zimujących stadiów przedimaginalnych osnui gwiaździstej Acantholyda posticalis Mats. w drzewostanach sosnowych będących ogniskami gradacyjnymi szkodnika
Distribution of wintering pre-imaginal stages of the great web-spinning pine sawfly Acantholyda posticalis Mats. in Scots pine stands being the outbreak centres
Autorzy:
Sławski, M.
Mokrzycki, T.
Perliński, S.
Rutkiewicz, A.
Sławska, M.
Powiązania:
https://bibliotekanauki.pl/articles/980205.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
drzewostany sosnowe
szkodniki roslin
osnuja gwiazdzista
Acantholyda posticalis
larwy zimujace
eonimfy
pronimfy
rozmieszczenie przestrzenne
autumn survey
scots pine pests
eonymphae
pronymphae
abundance
distribution variability
Opis:
Acantholyda posticalis Mats. for over twenty years increases the extent of occurrence and causes defoliation of Scots pine stands. The population size is estimated annually based on the autumn surveys of phytophagous insects, but accuracy of these prognoses is far from satisfactory. The aim of the study was to describe the spatial distribution of pre−imaginal stages of A. posticalis wintering in the litter and soil to improve the methods of survey currently applied in Polish forestry. The research was carried out in four forest district located in different regions of Poland. In each forest stand three following zones were outlined: the belt of trees on the edge of the stand adjoining to young plantation or thicket, the belt 15−20 m from the stand edge and the belt in the forest interior at least 30−40 m from the edge of a stand. 152 trees were examined and 1540 plots of size 1×0.5 m were established under their canopy. The pre−imaginal stages were searched within each of these plots in the litter and soil to the depth of 20 cm. Later on they were divided into eonymphae and pronymphae, and counted. The significant differences in number of pre−imaginal stages of A. posticalis between studied forest stands in different forest districts were found. The spatial distribution of larvae wintering in the litter and soil was highly variable in scale of both stand and single tree. The abundance of larvae depended on the distance from the forest edge, but the values of this parameter calculated for trees in the same zone also varied substantially. The lowest mean abundance of pre−imaginal stages of A. posticalis denoted under pines growing at the edges of trees stand. Within the canopy projection on forest floor, the distribution of larvae was significantly dependent on the distance from the tree trunk. The highest abundance was observed within one meter from the trunk. The survey method currently used for primary pine pest assessment in Polish forests bases on ten plots and five of them are located 1.5 m from the tree trunk. In the light of presented results, the assessment of A. posticalis number could be inaccurate, because half of these plots in which scrutiny of litter and soil take place, omit the areas of higher concentration of wintering stages of the pest.
Źródło:
Sylwan; 2019, 163, 07; 556-563
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dokładność określenia zasobności na poziomie warstw gatunkowo-wiekowych w obrębowej metodzie inwentaryzacji
Accuracy of volume determination on the level of age-species layers in the stratified sampling method
Autorzy:
Banaś, J.
Drozd, M.
Bujoczek, L.
Zięba, S.
Zygmunt, R.
Powiązania:
https://bibliotekanauki.pl/articles/986687.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
powierzchnie probne
forest inventory
stratification
standard error
sample plot
variability coefficient
lesnictwo
drzewostany swierkowe
warstwy gatunkowo-wiekowe
inwentaryzacja lasu
zasobnosc drzewostanu
miazszosc drzewostanow
metoda obrebowa
dokladnosc pomiaru
Opis:
Statistical representative method of inventory based on stratified sampling is used for elaborate forest management plans in Poland. Strata are created according to the dominant tree species and age of stands. First stratum include stands with age from 21 to 30 years and the interval in the next strata is 10 years. Sample plot size depends on stand age and varies from 0.005 to 0.05 ha. According to the allocation pattern number of samples is proportional to age and total area of stands in a stratum. Diversification of number and size of sample plots has a profound influence of inventory precision in an age classes. The aim of the study is to analyse the accuracy of the stand volume determination on the level of age−species strata. Research was conducted based on the data obtained from periodic forest inventory in seven mountainous forest subdistricts located in the Kłodzko Basin (SW Poland). Norway spruce stands with total area of 39,935.45 ha and 6102 sample plots were chosen for analysis. Sampling fraction, mean number and volume of trees on a sample plot, coefficient of volume variability and standard error of volume were calculated for each stratum in analyzed forest subdistricts. Sample plots with size of 0.005 ha established in young stands (21−30 years) are characterized by small number of trees (4.3−7.6 in average) and the highest coefficient of volume variability (93%). Additionally, because of low age of stands, the number of plots is also small (18 on average), which influences the low precision of volume inventory in this stratum. Standard error of volume was on the mean level of 23% in the youngest age stratum and decreased with age of stands to 5% in the stands of 41−71 years and below this level in the strata with the older stands. Increasing the plot size in the youngest stratum will be effective way to improve accuracy of forest inventory in the method based on stratified sampling.
Źródło:
Sylwan; 2017, 161, 09; 715-722
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zmienność wybranych cech makrostruktury i gęstości drewna świerkowego (Picea abies (L.) Karst.) pochodzącego z drzewostanów rosnących na różnych siedliskowych typach lasu
Variability of selected features of macrostructure and density of Norway spruce wood (Picea abies (L.) Karst.) from stands growing in different forest habitats
Autorzy:
Michalec, K.
Wasik, R.
Barszcz, A.
Powiązania:
https://bibliotekanauki.pl/articles/979499.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
drzewostany rebne
swierk pospolity
Picea abies
drewno swierkowe
makrostruktura
sloje przyrostu rocznego
szerokosc
gestosc drewna
czynniki siedliska
typy siedliskowe lasu
common beech
provenance
variability
silvicultural value
Opis:
This paper presents the genetic variability in the growth parameters and morphological traits, as well as the silvicultural quality of progeny of 23 European beech (Fagus sylvatica L.) provenances from south−eastern Poland. The research was conducted on the experimental plot established in the Łosie Forest District in spring 2006. After 10 years, during the spring and autumn, we determined and measured the spring phenology and survival rate, the diameter at breast height (dbh), the tree height, and the straightness of trunk. The results obtained point out the considerable variability of analysed features, both within and between different beech populations (tab.). Highest and lowest survival rates are noted for the beeches from Lutowiska and Leżajsk (populations 451 and 461), respectively (fig. 2). Lowest mean height and dbh were achieved by beeches from Bircza (453), while the tallest and broadest trees were from the Kielce population (390) (fig. 3−4). The overall silvicultural assessment based on survival, height, dbh, spring phenological phases and straightness of the trunk revealed that the most valuable populations of beech are those originating from Kielce (390), Bircza (454), Strzyżów (459), Lesko (452), Rymanów (457) and Lutowiska (451). In turn, the analysis resulted in least favourable assessments for beeches from Bircza (453) and Gromnik (362). Thus, we confirmed also that trees of local origin are not always best−adapted to (and do not always grow best in) the place they originate from. The obtained results are highly relevant from the principles of creating the seed source regions for beech in Poland, as the proper selection of a population for the given place of growth may yield benefits for forest ecology and management.
Źródło:
Sylwan; 2019, 163, 03; 188-197
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Tendencje zmian długości termicznego okresu wegetacyjnego w północno-wschodniej Polsce
Trends in the length of the thermal growing season in the north-eastern Poland
Autorzy:
Chojnacka-Ożga, L.
Ożga, W.
Powiązania:
https://bibliotekanauki.pl/articles/986668.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
zmiany klimatyczne
okres wegetacji
dlugosc okresu wegetacji
dlugosc termicznego okresu wegetacji
zmiany dlugoterminowe
Polska Polnocno-Wschodnia
change climate
extended of growing season
variability of parameters of growing season
Opis:
In the context of climate change and global warming, a growing number of studies reported lengthening of the growing season for most of the Northern Hemisphere, which is associated with increase of air temperature. Evidences of the increase of the growing season length were noted through satellite data and phonological and meteorological observations. This article presents the studies on the temporal and spatial tendencies in the thermal growing season (TGS) length in north−eastern Poland in 1951−2015. The analyses were conducted using long−term and homogeneity daily data sets from 13 meteorological stations (fig. 1). The dates of beginning and end of the TGS were determined by Huculak−Makowiec method. Trends in the TGS length as well as start and end dates were analysed for the whole study period as well as for successive 30−years periods: 1951−1980, 1961−1990, 1971−2000 and 1981−2010. The results show a general increase of the length of the TGS in the north−eastern Poland in 1951−2015 period, however, there are spatial and temporal differences in TGS evolution. In the western and central part of the region, the growing season in the past 65 years became ca. 20 days longer, while in the eastern part the lengthening of TGS was weaker and amounted to 7−10 days. Most of this change is due to earlier onset of the TGS in spring (average for the western part =2.1 days/10 years, while for the eastern one – 1.2 days/10 years). The observed trends and tendencies show spatial and temporal variability in TGS evolution. Trends in parameters of TGS, calculated for 30−years period, varied directionally and spatially with no significant trends before 1980. In the period 1981−2010 the growing season was longer than in the previous years, the largest increases were found in the central part of the region (1.2 days/year), while the smallest in the south−eastern part (0.5 day/year). Since the 1980s the frequency of long growing seasons increased. A particularly large and steady increase of TGS occurred over the first 15 years of the 21st century. Length as well as start and end dates of the TGS displayed large inter−annual and decadal variability with tendencies for increased range of variability.
Źródło:
Sylwan; 2018, 162, 06; 479-489
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wysokość dwunastoletnich odnowień dębu szypułkowego na różnej wielkości gniazdach o wydłużonym kształcie w kierunku wschód-zachód
Height of the 12-year-old regeneration of pedunculate oak in the cut patches of different size with an elliptical shape in the east-west direction
Autorzy:
Drozdowski, S.
Andrzejczyk, T.
Buraczyk, W.
Turkot, S.
Powiązania:
https://bibliotekanauki.pl/articles/991740.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
rebnie gniazdowe
odnowienia lasu
odnowienia na gniazdach
gradient wschod-zachod
wydluzanie osi gniazda
drzewa lesne
dab szypulkowy
wzrost roslin
wysokosc drzew
patch cutting
pedunculate oak
gap size
spatial height variability
Opis:
The study presents spatial variation in the height of a 12−year−old oak regeneration in the north−south and east−west gradients in the cut patches with a similar width (28 m) but differing in length (33−70 m), with the longer side facing east−west direction. A comparison of the cut patches with an area of 7, 11 and 16 ares showed that oaks in large patches were on average 25% higher than in small patches and the diversity of trees in the WE and NS gradients depended on the size of the patch. In each case, the lowest trees occurred in the zone of strong root competition of shelterwood, whose influence decreased with the enlargement of the cut patches. The results of the study show that the establishment of large (15−20 ares) elliptical or rectangular patches whose area can be expanded by lengthening the axis in the east−west direction is the recommended method of pedunculate oak renewal in forest practice.
Źródło:
Sylwan; 2013, 157, 06; 434-441
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł

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