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Spatial pattern of trees of different diameter classes in managed pine stands (Pinus sylvestris L.) of different age

100%

Szmyt J.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2010

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tom 09

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nr 3-4

The present research was conducted in managed stands of Scots pine (Pinus sylvestris L.) at different age in Poland. All the investigated stands were planted and thinned according to selection thinning. Analysis of spatial structure concerned trees of different categories (DBH classess) depending on the age of stand. Spatial distribution of trees was investigated using two commonly used methods: Clark-Evans R index and Ripley's L(t) function. In stands of age 43 and 65 the effect of the initial spacing was observed and all living trees were distributed regularly at the smallest distances and at larger spatial scale they were spaced randomly. Random type of spatial structure of trees was observed when smaller and larger trees were taken into consideration, separately. In case of stands at the age 90 the effect of the initial planting on the spatial structure of trees was not observed even at the smallest distances independently of the category of trees taken into account. All living trees in these stands were distributed randomly. Only in two stands clumps of trees were observed and one concerned smaller trees and the other - larger trees. Size differentiation index was small for all stands. The lowest values was ascertained in the oldest stands.

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Hodowla lasu wobec zmian klimatycznych – wyzwania, ograniczenia, perspektywa

100%

Szmyt J.

Sylwan

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2020

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tom 164

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nr 11

Changing environmental conditions that result from changes in the Earth’s climate system have a multifaceted impact on both forest ecosystems and forestry. Taking into account the causes of the observed climate changes, they will also influence the silvicultural practices in order to realize the future goals of forest management. The significance of this impact is due to the fact that the growth and development of forests as well as its ability to resist the biotic and abiotic threats largely depends on silvicultural operations that are conducted in a given forest stand. The adopted silviculture procedures determine at the same time the achievement of the intended goals of modern ultifunctional forest management. Throughout history, forestry and silviculture faced various challenges resulting from the changing environment, however, the currently observed variation in the environment has no equivalent in the past. Therefore, there is a need to recognize the threats to forest ecosystems resulting from these changes and to develop adaptive measures in relation to present and future forests so as to maintain their continuity of existence and ensure the sustainability of the forest use under the different scenarios of climate change. However, the uncertainty associated with both the pace and the magnitude of changes, as well as with the potential response of forest ecosystems to these changes, highlights the difficulties in developing an optimal strategy for adaptive management of forest ecosystems. To achieve the goals of multifunctional forestry in the future, the forest practitioners will have to take into account both a risk and an uncertainty in adaptive forest management. Despite the fact that there has been no single procedure elaborated so far, it is possible to indicate the principles of adaptive silviculture that allow achieving the objectives of forest management in the future. To some extent, these principles are implemented by the concept of close−to−nature silviculture.

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Zróżnicowanie strukturalne wybranych drzewostanów dębu szypułkowego (Quercus robur L.) występujących na terenie Płyty Krotoszyńskiej

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Szmyt J.

Leśne Prace Badawcze

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2017

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tom 78

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nr 1

The oak forests growing on the Krotoszyn Plateau are the biggest and most valuable oak forest complexes in Poland. The purpose of this study was to analyze the structural diversity of oak (Q. robur L.) stands older than 140 years. Two natural stands located within the forest reserve as well as two managed stands were chosen for investigation. Species and tree size diversity were analyzed using different measures and spatially explicit and inexplicit indices. The results indicate that the structural diversity of the protected oak forests did not differ significantly from that of managed stands. On the contrary, undisturbed natural processes in protected forests can result in a low diversity of some structural attributes in such stands. Although most indices pointed towards a higher structural diversity in protected forests, the differences were not large, especially in the case of spatially explicit indices. The spatial arrangement of live trees was either random, aggregated or regular, with the latter clearly dominating managed, poorly mixed oak stands. Furthermore, a lack of natural disturbances strong hornbeam expansion, in which case strict protection is not favorable for oak sustainability as it creates unsuitable conditions for oak regeneration beneath the hornbeam canopy.

4

Spatial structure of managed beech-dominated forest: applicability of nearest neighbors indices

100%

Szmyt J.

Dendrobiology

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2012

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tom 68

High structural diversity is often attributed to old-growth forests, usually established naturally and unmanaged. Forest diversity should be considered not only in terms of species diversity and richness but also the variation in trees dimension and their spatial distribution have to be taken into consideration. The main goal of this paper was the answer if nearest neighbor indices are suitable for spatial forest structure description. To answer this question results obtained from 3 managed beech-dominated forests from natural regeneration are presented and discussed. The following indices were calculated: Clark-Evans aggregation index (R), DBH and height differentiation indices (TD and TH, respectively) and mingling index (DM) analyzing horizontal and vertical spatial structure of the forest. Results indicated that managed beech forests demonstrated rather homogenous spatial structure in both aspects. Living trees as well as future crop trees were mostly regularly distributed. Spatial variation in DBH and height between living nearest neighbors was rather low. The lowest variation in sizes was demonstrated by future crop trees. Mature beech forests revealed single species structure and other tree species – if present – were spatially segregated from beech. It can be supposed that high homogeneity structure of these forests results from biological characteristics of this species as well as thinning treatments conducted by foresters.

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Zróżnicowanie przestrzenne niepielęgnowanych drzewostanów brzozy brodawkowatej (Betula pendula L.) odnowionych sadzeniem

63%

Szmyt J., Korzeniewicz R.

Leśne Prace Badawcze

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2012

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tom 73

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nr 4

6

Zróżnicowanie przestrzenne i grubościowe drzew w niepielęgnowanych drzewostanach sosnowych o różnym zagęszczeniu początkowym

63%

Szmyt J., Ceitel J.

Sylwan

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2011

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tom 155

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nr 11

7

Poziome rozmieszczenie drzew w osiemdziesiecioletnich gospodarczych drzewostanach swierkowych w Nadlesnictwie Slawno

63%

Szmyt J., Korzeniewicz R.

Sylwan

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2007

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tom 151

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nr 09

3-11

8

Czy naturalne procesy ekologiczne w juwenilnej fazie rozwoju drzewostanu założonego sztucznie różnicują jego strukturę przestrzenną?

63%

Szmyt J., Korzeniewicz R.

Leśne Prace Badawcze

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2014

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tom 75

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nr 2

9

Czy cała Puszcza Białowieska powinna być parkiem narodowym?

63%

Zientarski J., Szmyt J.

Leśne Prace Badawcze

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2017

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tom 78

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nr 1

In Poland, the stormy discussion on the future of the Białowieża Forest has been ongoing already for a long time. The disputes are mostly focused on seeking answers to two questions: how to protect these unique forest ecosystems and whether forest management threatens their naturalness. The discussion has grown stronger after the recent, enormous outbreak of Ips typographus in the Forest. The Białowieża Forest has been managed for years with no negative effect. However, antagonists of foresters blame forest management for degradation of the Forest’s ecosystems, which is caused by favoring the economic value of timber expected to be harvested in keeping with the management plans of 3 forest districts located in the Białowieża Forest. At any rate, such assumption, has nothing to do with reality. During this discussion the idea to extend the national park for all the Białowieża Forest revived. In this paper, we reviewed the economic, social and ecological dimensions which should be taken into consideration before making a decision on extending the Białowieża National Park. It should be underlined that the Park’s area is already under the strict protection; furthermore, 2/3 of the area of neighboring managed forests are under legal protection (the nature reserves, NATURA 2000, the so-called reference forests, etc.). All things considered, we cannot find any reasonable purpose (ecological, financial or social) for expanding the Park’s area from 10 500 ha (present status) to 62 500 ha (after extension). Also, we are convinced that sustainable forest management conducted in managed parts of the Białowieża Forest, which comprises the fulfillment of all forest functions and services, should not be perceived as a threat to naturalness of the Forest’s ecosystems.

10

Struktura przestrzenna drzew roznej grubosci w drzewostanach sosnowych [Pinus sylvestris L.] o roznym zageszczeniu poczatkowym

63%

Szmyt J., Zabielski M.

Leśne Prace Badawcze

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2010

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tom 71

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nr 3

267-277

11

Przestrzenne zroznicowanie drzewostanow daglezjowych [Pseudotsuga menziesii [Mirbel] Franco] odnowionych sadzeniem na siedliskach BMsw i LMsw

63%

Szmyt J., Korzeniewicz R.

Sylwan

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2010

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tom 154

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nr 11

791-800

12

Ocena przeżywalności i zdrowotności nasadzeń jarzębu brekinii [Sorbus torminalis (L.) Crantz] w Nadleśnictwie Milicz

63%

Pusz W., Szmyt J.

Progress in Plant Protection

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2021

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tom 61

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nr 1

13

Spatial autocorrelation of tree attributes in naturally regenerated managed beech (Fagus sylvatica) forests in the Beskid Niski Mountains, southern Poland

63%

Szmyt J., Stoyan D.

Dendrobiology

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2014

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tom 71

European beech (Fagus sylvatica L.) is a widely distributed forest tree species in central, southern and western Europe. In Poland it reaches the eastern limit of its natural range. The three forest stands selected for the analysis presented here are located in the Dukla Forest Inspectorate, southern Poland in the Beskid Niski Mountains. The measurement plots were rectangular, 0.35 ha each, established under homogenous conditions. The origin of all stands is natural and up to now they were thinned several times according to selective thinning method. The main tree species on each plot is European beech. In each stand (x, y) coordinates, the species, total heights of trees and their diameters at breast height were recorded. Total tree height, diameter, basal area and tree volume were considered as marks in statistical analysis. The aim of this paper is to find out the differences in the spatial autocorrelation of different tree marks as well as to explain the reasons for differences if they were observed. The empirical mark correlation functions indicated that there is a negative spatial correlation of all these marks in all three forest stands, i.e. trees close together tend to have smaller marks than the average in the stand. No significant spatial correlation was found for the tree heights. Diameter, basal area and volume show some correlation, but only in one stand a deviation test showed that the detected spatial correlation is significant. The mark variograms indicated that neighboring trees tended to have similar sizes.

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Changes in the density and spatial structure of trees in pine stands planted at different initial spacing

63%

Ceitel J., Szmyt J.

Seria Biologiczna. Uniwersytet im. Adama Mickiewicza w Poznaniu

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2004

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tom 69

15

Horizontal distribution of the young generation of trees in fir-beech [Abies alba Mill., Fagus sylvatica L.] stands developed with the improved gradual group cutting system

63%

Szmyt J., Sugiero D.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2006

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tom 05

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nr 2

16

Smukłość 30-letniego niepielęgnowanego drzewostanu nrzozy brodawkowatej (betula pendula Roth.)

51%

Korzeniewicz R., Borzyszkowski W., Szmyt J., Kazmierczak K.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2016

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tom 15

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nr 2

17

Ocena biometryczna buka zwyczajnego (Fagus sylvatica L.) pochodzącego z odnowień naturalnych na przykładzie drzewostanów w Nadleśnictwie Kościerzyna

51%

Korzeniewicz R., Stefanski W., Kowalkowski W., Szmyt J.

Forestry Letters

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2013

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tom 106

18

Charakterystyka biometryczna rozpieraczy w różnowiekowych młodnikach sosnowych w Nadleśnictwie Nowogard

51%

Korzeniewicz R., Rapa M., Szmyt J., Wawro T.

Zarządzanie Ochroną Przyrody w Lasach

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2014

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tom 08

19

Charakterystyka biometryczna rozpieraczy w młodnikach sosnowych w Nadleśnictwie Kalisz

51%

Korzeniewicz R., Skoczylas M., Szmyt J., Wawro T.

Zarządzanie Ochroną Przyrody w Lasach

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2014

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tom 08

20

Analiza mozliwosci wykorzystania sztucznych sieci neuronowych do szacowania sil konkurencji wewnatrzgatunkowej w trzydziestoletnich drzewostanach brzozy brodawkowatej [Betula pendula Roth]

51%

Niedbala G., Korzeniewicz R., Szmyt J.

Technika Rolnicza Ogrodnicza Leśna

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2010

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nr 04

19-22

Celem pracy było zbudowanie predykcyjnego modelu neuronowego, mającego wyznaczyć siłę konkurencji wewnątrzgatunkowej brzozy brodawkowatej w trzydziestoletnich drzewostanach. Dla jego realizacji zebrano dane empiryczne z pierwszych dziesięciu lat drzewostanu oraz z ostatniego - trzydziestego roku. Do budowy modelu użyto dwóch zmiennych niezależnych - średnicy i wysokości drzew (w każdym roku), łącznie 18 zmiennych. Wygenerowany model został oparty na sieci MLP z jedną warstwą ukrytą. Na jego podstawie przeprowadzono analizę wrażliwości sieci, która określiła jednoznacznie dwie najważniejsze cechy wpływające na przeżywalność brzozy brodawkowatej.

Ograniczanie wyników

Spatial pattern of trees of different diameter classes in managed pine stands (Pinus sylvestris L.) of different age

Hodowla lasu wobec zmian klimatycznych – wyzwania, ograniczenia, perspektywa

Zróżnicowanie strukturalne wybranych drzewostanów dębu szypułkowego (Quercus robur L.) występujących na terenie Płyty Krotoszyńskiej

Spatial structure of managed beech-dominated forest: applicability of nearest neighbors indices

Zróżnicowanie przestrzenne niepielęgnowanych drzewostanów brzozy brodawkowatej (Betula pendula L.) odnowionych sadzeniem

Zróżnicowanie przestrzenne i grubościowe drzew w niepielęgnowanych drzewostanach sosnowych o różnym zagęszczeniu początkowym

Poziome rozmieszczenie drzew w osiemdziesiecioletnich gospodarczych drzewostanach swierkowych w Nadlesnictwie Slawno

Czy naturalne procesy ekologiczne w juwenilnej fazie rozwoju drzewostanu założonego sztucznie różnicują jego strukturę przestrzenną?

Czy cała Puszcza Białowieska powinna być parkiem narodowym?

Struktura przestrzenna drzew roznej grubosci w drzewostanach sosnowych [Pinus sylvestris L.] o roznym zageszczeniu poczatkowym

Przestrzenne zroznicowanie drzewostanow daglezjowych [Pseudotsuga menziesii [Mirbel] Franco] odnowionych sadzeniem na siedliskach BMsw i LMsw

Ocena przeżywalności i zdrowotności nasadzeń jarzębu brekinii [Sorbus torminalis (L.) Crantz] w Nadleśnictwie Milicz

Spatial autocorrelation of tree attributes in naturally regenerated managed beech (Fagus sylvatica) forests in the Beskid Niski Mountains, southern Poland

Changes in the density and spatial structure of trees in pine stands planted at different initial spacing

Horizontal distribution of the young generation of trees in fir-beech [Abies alba Mill., Fagus sylvatica L.] stands developed with the improved gradual group cutting system

Smukłość 30-letniego niepielęgnowanego drzewostanu nrzozy brodawkowatej (betula pendula Roth.)

Ocena biometryczna buka zwyczajnego (Fagus sylvatica L.) pochodzącego z odnowień naturalnych na przykładzie drzewostanów w Nadleśnictwie Kościerzyna

Charakterystyka biometryczna rozpieraczy w różnowiekowych młodnikach sosnowych w Nadleśnictwie Nowogard

Charakterystyka biometryczna rozpieraczy w młodnikach sosnowych w Nadleśnictwie Kalisz

Analiza mozliwosci wykorzystania sztucznych sieci neuronowych do szacowania sil konkurencji wewnatrzgatunkowej w trzydziestoletnich drzewostanach brzozy brodawkowatej [Betula pendula Roth]