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EN
The mean volume of stands with fir and beech in their species composition in the study plots Święty Krzyż 1 and Święty Krzyż 2 was 521 m3/ha and 203 m3/ha respectively. These stands were many-storeyed and of many generations with the structure of the distribution of trees by d.b.h. close to Liocourt-Meyer curve. In volume of standing dead trees and dead wood laying on the ground, amounting together to 41.1% of stand volume of living trees in the plot Święty Krzyż 1 and 171.6% in the plot Święty Krzyż 2, predominated fir 99.4% and 100% in total volume of standing dead trees, and 46,2% and 82% in total volume of laying dead wood in respective plots. Fir was most abundant in the new growth layer (78.3% in the plot Święty Krzyż 1, and 39% in the plot Święty Krzyż 2), while beech decidedly dominated in the upgrowth layer (54.2% and 50.8% in respective plots). The stand in the plot Święty Krzyż 1 was considered to be in the growing up stage with the phase of storeyed form, while the one in the plot Święty Krzyż 2 in a transitional stage between the break up stage and the growing up stage with an inter­mediate phase between the regeneration phase and the phase of storeyed form.
PL
Praca zawiera charakterystykę zmian wybranych cech, dotyczących m.in. budowy, struktury i składu gatunkowego drzewostanów w rezerwacie „Łabowiec", w latach 1980-1990. Вadania oparto na analizie danych zebranych na 15 poletkach próbnych, rozmieszczonych według zasad inwentaryzacji statystyczno-matematycznej, i na 2 klasycznych powierzchniach doświadczalnych, usytuowanych w charakterystycznych fragmentach rezerwatu.
EN
This paper describes the changes in the chosen stand characteristics which took place in the forest reserve „Łabowiec" (Western Carpathians - Beskid Sądecki) during 1980-1990. The reserve is situated at the elevation of 840-960 m above sea level, and Dentario glandulosae - Fagetum is the plant association which has developed there. The study was based on the analysis of the data collected in 15 sample plots, 0.05 ha each, distributed according to the rules of the statistical and mathematical inventory, and in 2 classical experimental areas (area I - 0.75 ha and area II - 0.70 ha) situated in the characteristic fragments of the reserve. Stands in the optimum stage of development occupy 40% of the reserve area, those in the growing up stage 33%, and in the disintegration stage 27%. The investigated stand development stages differ from one another with respect to stand volume, tree loss, ingrowth, and volume increment (tab. 2). The reserve fragment with high (ir percentage in their species composition were characterized by greater stand volume and increment. The mean stand volume calculated on the basis of the sample obtained from 15 circular plots considerably increased during the investigated decade, from 454 to 492 cu. m per ha. The current volume increment was high and it amounted to 11.0 cu. in per ha per year (tab. 2). The study carried out in the classical areas showed that in the reserve section (area 1) characterized by a high fir percentage in its species composition (41.8% in 1980, and 27.2% in 1990), in spite оf the advanced senescent stage, the stand volume was relatively high, and it amounted to 666 cu. in per ha in 1990 (671 cu. m per ha in 1980) (tab. 5), The stand in the growing up stage (area II) with small percentage of fir (9.2% in 1980 and 7.5% in 1990) was characterized by a relatively low volume (469 cu. m per ha in 1980 and 489 cu. m per ha in 1990) (tab. 5). The greatest changes in the species composition occurred in the area 1 (lab. 5 and 6). In those fragments of the reserve where fir formed an admixture (area 11) its percentage slightly decreased from 4.2% to 7.5%, while the percentage of beech increased from 90,8% to 92,5% (tab. 5). The data obtained in the circular plots indicated no changes in the species composition determined by volume. On the other hand, there was a change in the species composition determined on the basis of the number of trees (tab. 2). The maintenance of the same volume percentage of fir in the stand species composition over the decade, in spite of the decreasing number of trees, indicated that the increment of fir trees which survived over that period of time compensated for a considerable loss in the number of trees and a very small ingrowth. The fir as well as beech reached a highest index of stand quality class - I. The d.b.h. distribution of all trees in area I changed during the 10-year-period from Pearson's type I to type I (J), while in area 11 the type I (U) was maintained (tab. 7). The d.b.h. distribution in the circular sample plots changed in case of 11 plots, while in 4 plots the type present in 1980 was maintained for the next 10 years (tab. I, fig. 1-5). The tree height distribution in area I and II maintained the normal distribution in case of all tree species together (tab. 8). The tree height distribution in the circular sample plots representing the optimum and the destruction stage maintained the normal distribution during the 10-year-period, while in the growing up stage the type changed from I (U) to I (J) (tab. 1). Fir dominated among the dead trees (tab. 3). The analysis of the species composition of the regeneration indicated a very negative tendency towards decreasing the percentage of fir (tab. 4). It should however be added that the upgrowth was almost completely damaged by deer browsing and bark scraping, and the young natural reproduction by browsing. The fir mortality, very small ingrowth and the decrease in fir percentage in the species composition of the regeneration may bring about a complete elimination of fir from the reserve, and formation of beech stands. This tendency has also been observed in other parts of Carpathians.
PL
Na podstawie analizy rozkładu pierśnic oraz wysokości, zasobności, składu gatunkowego, masy posuszu i innych cech drzewostanu lipowego w Obrożyskach, scharakteryzowano - na przykładzie 3 powierzchni doświadczalnych - dwa stadia rozwojowe lasu pierwotnego. Podano także skład gatunkowy odnowień. W rezerwacie zwraca uwagę duża zasobność drzewostanów i ich dobra jakość.
EN
The purpose of this study was to determine stand characteristics of common linden (Tilia cordata Mill.) in Obrożyska near Muszyna (Southern Poland) (tab.l). The stand is considered as relict from the Atlantic; period 4000—2000 years B.C. when deciduous stenothermal trees expanded and mixed broadleaved forests appeared [9]. According to Korpel criteria [6] sample plots represent the up-growing stage in transition to the optimum stage with a noticeable ageing phase (Plot 1, 2) and the up-growing stage with a selection phase (Plot 3) (Tab. 1) in some parts. First of all the obtained results show a high stand volume (667—757 cu. m per ha) (Tab. 2) while according to Żyłkin labels [1] the maximum stand volume of pure linden stands on sites of the first stand quality class reaches 455 cu. m per ha. In spite of several generations, different stages, and phases of development, the d.b.h. distribution of linden is compatible with normal d.b.h. distribution on all sample plots (Tab. 3, Fig. 1, 2, 3). The storeyed structure is characteristic for virgin type forests of linden (Plot 1, 2). In selected storeys every generation is found showing horizontal density. Selection structure (selection phase) is formed in the presence of a greater share of shade-resistant species in the stand (like fir and hornbeam) (Plot 3) (Fig. 9). Linden is characterized by a high quality, over 20% of trees reach the highest values. A large share of fir, sycamore, maple in new growth on plot no. 1 and of hornbeam and sycamore on plot no. 2 and 3 can cause concern about the existence of linden (Tab. 6). In the up-growth layer the share of linden is larger and becomes predominant and co-predominant species in this phase of stand development. Analysis of data from 1945 [2] and from 1990 shows that the stand volume has increased from 438 cu. m per ha to 692 cu. m per ha and the share of linden has increased from 63,3% to 90,6% in that period. From the economic point of view the introduction of common linden into stands on suitable forest sites of foothills and lower parts of lower mountain zone not only as a cultivation and biocoenotic but also high productive admixture is advisable though it is currently not realized in practice [2]. Linden is especially recommended for planting under thinned fir stands.
PL
Na podstawie analizy zasobności, składu gatunkowego, krzywych rozkladu pierśnic, budowy warstwowej, liczebności odnowień oraz innych wybranych cech, scharakteryzowano dolnoreglowy drzewostan jodłowy o dobrze wykształconej strukturze prze rębowej i wysokim zapasie.
EN
Studies were carried out in natural fir stand of Gorgany Range (Eastern Carpathians - Ukraine) in 1989, Till 1980 the fir stand had been managed by assorted-selection cutting system. From 1980 the stand has been under strict protection as a result of including it in State Carpathian Natural Park. Investigated stand is characterized by high mean stand volume - 942 m3/ha (Tab. 1) when its species composition consist of fir - 88%, spruce — 8% and beech - 4%. Tree distribution in diameter classes (Tab. 1, Fig. 1), stand statistical parameters (Tab. 2) and comformability to Liocourt-Meyer theoretical distribution for spruce and beech are indicative of well formed selection structure. Compound stand structure, vertical and step like density (Fig. 2) and wide age range indicate on its many storied and all-generation character. Composition and amount of natural reproduction is not an evidence of fir declining what is typical for Western Carpathians (Tab. 3). Advisable values of relative crown length and coefficient of slenderness show good conditions for tree growth and its high resistance from snow and wind activity irrespective of biosocial tree position (Tab. 4). Repeated observation on fixed investigated plot would enable to evaluate growth dynamics of selection stand which has been under strict protection for short time.
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