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Określanie wybranych cech drzewostanów sosnowych z wykorzystaniem chmur punktów pozyskanych w procesie automatycznego dopasowania cyfrowych zdjęć lotniczych

100%
Hawrylo P.
Sylwan
|
2017
|
tom 161
|
nr 09
Recent research show that image−derived point clouds (IPC) can be successfully utilized in the context of estimation of selected forest parameters. However there are still some topics for further investigation in the context of using archival data. Particularly, in case of forest stands in Poland the number of such studies is limited. This study investigates the usefulness of airborne IPC for estimation of Lorey's height (H), basal area (G) and growing stock volume (V) of Scots pine stands. Additionally, the accuracy of predictive models is analyzed for images acquired in the same year as the field reference data were collected (2015) and for archival images acquired in 2012. The study was performed in Janów Lubelski Forest District (south−eastern Poland) on approximately 7,800 ha. The measurements from 94 circular plots were used as the reference data. The Area Based Approach and multiple linear regression were used to create predictive models. For each analyzed dependent variable variety of IPC characteristics were evaluated to select the most accurate predictive models. The best model for each variable was selected based on Akaike Information Criteria and RMSE. The same predictor variables were used for both years of aerial images aquisition. For models comparison the one−sided bootstrap test was used. The RMSPE for H, G and V in case of images acquired in 2015 amounted to 5.3, 16.3 and 17.3%, respectively. Analogically, the relationship between predicted and observed values (R²) amounted to 0.96, 0.47 and 0.81. The finally selected models had three, one and two predictors for H, G and V, respectively. The difference between accuracy of models based on aerial images from 2012 and 2015 was not statistically significant for all analyzed variables. The obtained results show high potential of using airborne image−derived point clouds for forest inventory activities in Scots pine dominated stands.
2

Zmiany wybranych cech taksacyjnych drzewostanow Gorczanskiego Parku Narodowego w okresie 1992-2002 na tle oceny naturalnosci lasow gorczanskich z 1932 roku

100%
Chwistek k.
Roczniki Bieszczadzkie
|
2008
|
tom 16
125-144
3

Mozliwosci produkcyjne drzewostanu lipowego w rezerwacie 'Las Lipowy Obrozyska'

75%
Gralek K., Jaworski A., Kolodziej Z., Majerczyk K.
Acta Agraria et Silvestria. Series Silvestris
|
2009
|
tom 47
3-26
The aim of this study was to determine the productive potentiality (stand volume, basal area, and their increments) of the natural little leaf linden stand 26.68 ha in area. This stand is a part of the Obrożyska nature reserve of the total forest area of 98.25 ha. Measurements were carried out in 1995 and 2005 on 26 4-are sample plots established according to the statistical-mathematical system of forest inventory and control, and in 1999 and 2000 on three permanent sample plots which represented different developmental stages and phases of the virgin forest. Between 1990 and 2005, the mean volume of the entire stand increased from 538 to 567 m3/ha. In the growing up stage it increased from 554 to 584 m3/ha, while in the optimum stage from 510 to 541 m3/ha. The volume increment in these two stages was 66 and 51 m3/ha/10 years respectively. Volume of the stand representing the growing up stage in transition to the optimum stage (Obrożyska I classical permanent sample plot) increased during the 10-year period from 700 to 768 m3/ha, while in the stand representing the initial phase of the optimum stage (Obrożyska II) it increased from 797 to 861 m3/ha, and in the stand representing the growing up stage (Obrożyska III) from 696 to 761 m3/ha. The volume increment in these three plots was almost 80, 96, and 82 m3/ha/10 years respectively. The stand volume per hectare of the little leaf linden forest in the Obrożyska reserve is one of the highest among stands of natural character in the Polish part of the Carpathians. A very high productive potentiality of the investigated little leaf linden stand permits to accept this tree species as the main species in stands of the submontane zone as well as in the lower part of the lower montane zone in the Poprad river valley and in the climate close to that of the surroundings of the town of Muszyna.
4

Budowa, dynamika, struktura i możliwości produkcyjne borów górnoreglowych na Pilsku

51%
Jaworski A., Pach M.
Acta Agraria et Silvestria. Series Silvestris
|
2010
|
tom 48
The purpose of the paper is to report on the structure and the potential production of tree stands in the belt of dense forest in the locality of Pilsko, which were formed as a result of connecting natural processes with various methods of cuttings. In two stands single cutting harvesting was applied, corresponding to single tree selection cutting (Einzelplenterung in German). In the third stand there was cutting in the form of small gaps which corresponds to mountain selection cutting (Gebirgsplenterung in German). In the control period (1998-2008) the stand volume on two plots, Pilsko 1 and Pilsko 3 increased from 448 to 479 m3/ha and from 237 to 298 m3/ha respectively, however, in Pilsko 2 the stand volume decreased slightly from 401 to 397 m3/ha. The increase in the volume of the stand reached from almost 5 m3/ha in Pilsko 2 to approximately 8 m3/ha per year in the other plots. The stability of the stand is ensured mainly by the presence of trees in the thinnest classes in the lower and medium layer of the stand as well as the continuous process of regeneration. In this context the stand in which cuttings were taken in the past, characteristic of mountain selection, exhibited more beneficial features. All the researched stands exhibited great differences in the age of trees which enabled them to be classified as uneven-aged stands. The age at the breast height diameter of the oldest drilled spruce was 344 years and frequently the encountered specimens of this variety are of the age of 223 and 276 years. The uneven-aged structure of the stands, however, does not simultaneously ensure a complex and stable structure. In order to form, or to maintain, stable upper mountain spruces, which are under partial active protection (outside reservations with total protection) mountain selection cutting, or cutting by a method of group selection, should be recommended. These methods of cuttings ensure the variations within the structure of the stands, which minimises the risk of large-area disintegration.
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