1. bookVolume 74 (2021): Issue 1 (December 2021)
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Journal
eISSN
1736-8723
First Published
24 Mar 2011
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2 times per year
Languages
English
access type Open Access

Changes during twelve years in three mature hemiboreal stands growing in a radiation model intercomparison test site, Järvselja, Estonia

Published Online: 01 Dec 2021
Page range: 112 - 122
Received: 14 Jun 2021
Accepted: 30 Aug 2021
Journal Details
License
Format
Journal
eISSN
1736-8723
First Published
24 Mar 2011
Publication timeframe
2 times per year
Languages
English
Abstract

In 2007, three mature hemi-boreal stands were selected from Järvselja forest district, South-East Estonia to establish one-hectare-large test plots for the international inter-comparison experiment of radiation models (RAMI). All trees with a stem diameter at breast height greater than 4 cm were mapped and measured in the field. In summer 2019, the forests were inventoried again. Here we present a summary of changes that occurred in the forest structure – mainly growth and mortality. In the birch stand basal area G has increased from 23.3 m2 ha-1 to 28.2 m2 ha-1 in the upper layer and the number of trees N has decreased from 654 to 565 ha-1. In the upper layer of spruce stand G has increased from 30.9 m2 ha-1 to 35.4 m2 ha-1 and N has decreased from 774 to 724 ha-1 and N substantially decreased in the lower layers from 912 to 577 ha-1. In the pine stand G has increased from 28.3 m2 ha-1 to 29.1 m2 ha-1 and N decreased from 1116 to 971 ha-1. The three test stands can be used now for validating remote sensing data-based estimates of forest inventory variables at single tree level.

Key words

Introduction

For the fourth international radiation model inter-comparison experiment (RAMI) three forest stands were selected at Järvselja, South-East Estonia (Kuusk et al., 2013; Widlowski et al., 2015). In each of the three forests a one-hectare-large square-shaped sample plot was established in 2007 and the positions of all trees with stem diameter at breast height d greater than 4 cm were mapped. The three sample plots represent typical examples of hemi-boreal forests – birch and spruce stands are growing on fertile soil and the pine stand is located on a transitional bog.

Since 2007, regular measurements of canopy gap fraction have been carried out in the stands (Lang et al., 2010; Lang et al., 2017; Kuusk et al., 2018; Lang & Pisek, 2019). There have not been any substantial stand structure alternating disturbances in the stands. Only in the birch stand we removed the understory trees that had d less than 4 cm to prepare the site for terrestrial laser scanning experiment in 2018. During the regular visits to the sites we have been observing occurrences of single tree mortality in the stands, changes in canopy conditions and also tree growth. Also, more precise coordinates of sample plot corners can be measured with differential GPS now. Therefore, in the summer of 2019 all three stands were fully inventoried to update the RAMI database, create a checkpoint for modeling experiments and validate remote sensing-based forest structure estimates.

Material and Methods
Stands

The birch stand is located at 58° 16’ 49.81’’ N, 27° 19’ 51.53’ E (Kuusk et al., 2013) and was 61 years old in 2019 (photo in Appendix 1). The stand grows on a typical brown soil and the site type according to Lõhmus (2004) is Aegopodium. The stand was thinned in September–October 2004 (Kuusk et al., 2013). Most of the small trees that formed a dense understorey (consists mainly of Tilia cordata Mill., Prunus padus L., Corylus avellana L., Acer platanoides L. and Fraxinus excelsior L.) layer were removed from the birch stand after thinning in March 2018 to prepare the site for terrestrial laser scanning. In 2019 about 90 retained trees in the regeneration layer that had grown bigger than 4 cm at breast height were mapped during field inventory in the birch stand.

The spruce stand is located at 58° 17’ 43.0’’ N, 27° 15’ 22.0’’ E (Kuusk et al., 2013) and was 71 years old in 2019 (photo in Appendix 1). The stand grows on a Gleyic Ferric Podzol and the site type according to Lõhmus (2004) is Oxalis-Vaccinium. Management has not been done in the stand since 2007 and also signs of earlier treatments are absent. The mortality of trees is rather high due to fungi that have infected stems that have had bark stripping damage by Alces alces. Another dominant cause of mortality is competition in the second and regeneration layer where many supressed trees were present in 2007.

The pine stand is located at 58° 18’ 40.89’’ N, 27° 17’ 48.41’’ E and was 136 years old in 2019 (photo in Appendix 1). Compared to (Kuusk et al., 2013) the sample plot coordinates are corrected based on GPS measurements and the azimuth of the y-axis is 6.25 degrees. The stand grows on a transitional bog where the soil consists of deep (>1.3 m) Sphagnum peat. Excess water and poor nutrient availability are the strong growth limiting factors. Tree mortality occurs mainly due to competition. The stand consists almost entirely of Scots pine trees. There has not been any management in the stand.

Mapping

The sample plots were established with a land survey instrument Nikon DTM-332 Total station (Nikon-Trimble Co., Ltd, Tokyo, Japan) in 2007. Corner points of 100 by 100 m square within each stand were marked with metal tubes. In 2014 and 2019, RTK differential GPS was used to measure the corner point coordinates in the Estonian state coordinate system EPSG:3301. In each sample plot nine permanent sampling points L1–L9 were established (Kuusk et al., 2013). Tree position coordinates were measured with the Nikon DTM-332 Total station in a local coordinate system with the test site south-west corner as the point of origin (0; 0). Sample plot corner coordinates were later used to convert tree positions to the EPSG:3301 system. Regrowth trees that were included first in 2019 as their d exceeded the 4 cm threshold, were positioned by measuring distances from their three closest neighbours.

Forest inventory

In 2007, two perpendicular diameters of tree stems at 1.3 m over root collar were measured with the electronic calliper Masser Racal (Savcor Group Ltd., OY, FIN-50100 Mikkeli, Finland). The average of the two measurements was used as an estimate of d. In 2019 we used Haglöf girth tape made of metal which allowed to take readings with a one-millimetre step. If a tree had substantial stem damage at the 1.3 m measurement position (mainly due to stripped bark by moose, Alces alces), then readings were taken below and above the damaged part of the stem and interpolated for 1.3 m standard height. Stem diameter measurements of dead trees were made with or without bark according to the remaining stem condition. For trees with a partially decayed stem, we used the d value from 2007. In 2007 only alive trees were measured. There are some snags remained from dead trees in 2007 still standing in the pine stand, but these are not included in this report.

The identical sample trees as in 2007 were measured in 2019 to establish upscaling models for tree height, live crown base and tree crown radius. At least two tree and crown base height measurements from different viewpoints were made with Haglöf Vertex IV (Haglöf Sweden AB, Klockargatan 8, 88230, Långsele, Sweden) and the average was calculated. Two perpendicular measurements of the crown projection on the ground were made for crown diameter. An additional set of sample trees were measured to replace dead sample trees and increase the number of observations for model construction. The number of sampled trees for height and crown dimensions was 84 in the spruce stand, 63 in the pine stand and 87 in the birch stand. The upscaling models were created for each tree species in each sample plot, but in the case of an insufficient number of sample trees (e.g., only few spruces in the pine stand) models from other stands were used.

Results

Measurements with differential GPS on the corner points of the test sites provided coordinates that were used to transform tree location maps into the Estonian basic map coordinate system (Table 1). There are small (less than 0.5 m) deviations from the planned ideal 100 by 100 m square which is explained by the decreased precision of GPS under forest canopy and also with small errors made in 2007 when the test sites were established.

Corner coordinates (EPSG:3301) of the test sites measured with differential GPS

Tabel 1. Katsealade nurgakoordinaadid Eesti põhikaardi süsteemis

Corner Xlocal ylocal XEPSG:3301 yEPSG:3301
Pine1 0 0 693110.5 6468117.1
Pine2 0 100 693121.6 6468216.7
Pine3 100 100 693220.8 6468205.6
Pine4 100 0 693210.1 6468105.9
Spruce1 0 0 690832.1 6466197.9
Spruce2 0 100 690814.5 6466296.3
Spruce3 100 100 690913.1 6466313.8
Spruce4 100 0 690930.6 6466215.4
Birch1 0 0 695299.9 6464769.0
Birch2 0 100 695280.7 6464867.2
Birch3 100 100 695378.8 6464886.6
Birch4 100 0 695397.7 6464788.0

In the birch stand (Figure 1) basal area G has increased from 23.3 m2 ha-1 to 28.2 m2 ha-1 in the upper layer and from 4.2 m2 ha-1 to 6.0 m2 ha-1 in the lower layers. The number of trees N in the upper layer has decreased from 654 to 565 ha-1 and increased in the lower layers from 377 to 401 ha-1 (Table 2). In the lower layer the increase in stand density is controlled by the cleaning in 2018, when most of the dense understorey and regeneration was removed. The natural mortality is occurring mainly on smaller trees and mean diameter of the dead trees is 10.4 cm (Figure 2, Table 2). The substantial change in mean tree crown length Lcr and crown radius Rcr of spruce trees in the regeneration layer is because in 2007 we used a model from the spruce stand, but in 2019 a model based on sample trees from the birch stand was applied. Compared to model prediction the mean value for relative live crown length for spruce sample trees in 2007 was 0.74 (n=3) and 0.87 (n=6) in 2019. As there is sufficient amount of light for Norway spruce regeneration trees in the birch stand, live crown base rise is small and live crowns extend almost to the ground.

Figure 1.

Map of live trees in RAMI birch stand in 2019. The symbols are scaled according to tree size. Cyan corresponds to birch, magenta to spruce, blue-violet to black alder, green to European aspen and grey to other species.

Joonis 1. RAMI kaasiku kasvavate puude kaart aastal 2019. Sümbolid on skaleeritud kujutamaks puude suurust, värvid vastavad metsakorralduse juhendile.

Birch stand summary of forest inventory 2007 and 2019. Notations are explained under table.

Tabel 2. Kaasiku 2007. ja 2019. aasta takseerandmete kokkuvõte.

Species Code N G D H Lcr Rcr
2007 inventory, upper layer
Populus tremula L. HB 78 2.848 21.6 27.5 9.4 1.95
Betula pendula Roth KS 399 13.44 20.7 26.9 9.4 1.63
Alnus glutinosa (L.) Gaertn. LM 176 6.921 22.4 23.8 9.8 2.04
Salix spp. PJ 1 0.044 23.7 24.0 9.9 1.96
2007 inventory, second layer
Ulmus glabra Huds. JA 1 0.010 11.3 15.9 8.1 0.99
Betula pendula KS 66 0.567 10.5 18.2 5.8 0.99
Alnus glutinosa LM 20 0.271 13.1 17.9 8.5 1.40
Tilia cordata PN 205 2.622 12.8 16.5 9.0 1.93
Fraxinus excelsior SA 30 0.281 10.9 17.6 9.2 1.64
Acer platanoides VA 16 0.159 11.2 16.3 8.5 1.85
2007 inventory, regeneration layer
Picea abies (L.) H. Karst. KU 39 0.245 8.9 10.3 4.8 1.16
2019 inventory, upper layer
Populus tremula HB 64 4.129 28.7 31.8 10.7 2.30
Betula pendula KS 342 15.44 24.0 29.4 11.5 1.97
Alnus glutinosa LM 159 8.654 26.3 26.4 13.1 2.27
2019 inventory, second layer
Ulmus glabra JA 1 0.015 13.8 17.3 11.0 2.03
Betula pendula KS 27 0.275 11.4 19.7 8.0 1.20
Alnus glutinosa LM 18 0.318 15.0 20.6 10.7 1.65
Tilia cordata PN 264 4.369 14.5 20.2 13.0 2.13
Fraxinus excelsior SA 18 0.263 13.6 20.4 12.3 2.12
Acer platanoides VA 20 0.289 13.6 18.7 12.5 2.16
2019 inventory, regeneration layer
Picea abies KU 53 0.511 11.1 13.4 11.6 1.54
2019 inventory, dead trees
Dead 2007–2019 - 159 1.349 10.4 - - -

N – number of trees; H – mean tree height, m; D – mean tree diameter at breast height, cm;

Lcr – mean length of live crown, m; Rcr – mean maximum radius of crown, m.

Figure 2.

Changes in stem breast height diameter distribution in the birch stand. Label (d) is for the trees that died between two measurements made in 2007 and 2019.

Joonis 2. Kaasiku puude diameetrijaotuse muutus. Ajavahemikus 2007–2019 surnud puud (d) on eraldi välja toodud.

In the spruce stand (Figure 3) basal area has increased from 30.9 m2 ha-1 to 35.4 m2 ha-1 in the upper layer and from 6.8 m2 ha-1 to 7.1 m2 ha-1 in the lower layers. The number of trees in the upper layer has decreased from 774 to 724 ha-1 and substantially decreased in the lower layers from 912 to 577 ha-1 (Table 3, Figure 4). We distinguished two separate classes of spruces in the regeneration layer based on their competition status according to the shape of the crown and increment of the top shoot.

Figure 3.

Map of alive trees in RAMI spruce stand in 2019. The symbols are scaled according to tree size. Magenta corresponds to spruce and cyan corresponds to birch.

Joonis 3. RAMI kuusiku kasvavate puude kaart aastal 2019. Sümbolid on skaleeritud kujutamaks puude suurust, värvid vastavad metsakorralduse juhendile.

Spruce stand summary of forest inventory 2007 and 2019.

Tabel 3. Kuusiku 2007. ja 2019. aasta takseerandmete kokkuvõte.

Species Code N G D H Lcr Rcr
2007 inventory, upper layer
Populus tremula HB 2 0.052 18.2 25.2 7.1 1.51
Betula pendula KS 143 3.607 17.9 24.7 8.7 1.52
Picea abies KU 624 27.04 23.5 23.8 12.0 1.81
Alnus glutinosa LM 3 0.097 20.3 22.6 9.6 2.05
Pinus sylvestris L. MA 2 0.109 26.3 24.5 10.4 2.11
2007 inventory, second layer
Betula pendula KS 152 1.024 9.3 18.1 4.9 0.92
Picea abies KU 517 5.015 11.1 14.7 6.2 1.17
2007 inventory, regeneration layer
Picea abies KU 89 0.188 5.2 5.7 2.8 1.09
Picea abies KU 157 0.586 6.9 9.1 3.5 1.10
2019 inventory, upper layer
Populus tremula HB 2 0.064 20.2 27.3 6.6 1.39
Betula pendula KS 132 4.489 20.8 28.0 10.2 1.67
Picea abies KU 585 30.61 25.8 26.7 12.1 1.57
Alnus glutinosa LM 3 0.111 21.7 24.4 12.3 2.12
Pinus sylvestris MA 2 0.139 29.7 27.2 13.4 2.70
2019 inventory, second layer
Betula pendula KS 45 0.494 11.8 23.1 5.2 0.93
Picea abies KU 375 4.198 11.9 16.4 7.1 1.04
2019 inventory, regeneration layer
Picea abies KU 87 0.248 6.0 7.2 3.2 0.92
Picea abies KU 70 0.326 7.7 11.7 4.8 0.92
Dead 2007–2019 - 394 1.861 7.8 - - -

Figure 4.

Changes in stem breast height diameter distribution in the spruce stand. Label (d) is for trees that died between two measurements made in 2007 and 2019.

Joonis 4. Kuusiku puude diameetrijaotuse muutus. Ajavahemikus 2007–2019 surnud puud (d) on eraldi välja toodud.

While H and G increased as in the birch stand, the crown radius decreased and live crown length remained almost the same for the spruces in the upper layer and second layer between the two measurements (Table 3). Heights to live crown base were measured with hypsometer and although random errors are possible, there is probably no systematic error. Measurements of crown diameter are prone to systematic errors as the interpretation of crown projection may have been slightly different in 2007 and 2019. However, it is not excluded that live crown diameter has decreased considering the conical shape of the Norway spruce crown (Kantola & Mäkelä, 2006) and the live crown base rise with stand age (Valentine & Mäkelä, 2005), and that the mean live crown length in the spruce stand remained almost the same as in 2007.

Summary of forest inventory 2007 and 2019 of the pine stand.

Tabel 4. Männiku 2007. ja 2019. aasta takseerandmete kokkuvõte.

Species Code N G D H Lcr Rcr
2007 inventory, upper layer
Pinus sylvestris MA 1116 28.25 18 16.1 4.5 1.52
2007 inventory, regeneration layer
Betula pendula KS 6 0.014 5.5 4.1 2.9 0.78
Picea abies* KU 1 0.002 5.0 5.0 1.8 1.09
2019 inventory, upper layer
Pinus sylvestris MA 971 29.09 19.5 17.4 4.6 1.53
2019 inventory, regeneration layer
Betula pendula KS 6 0.022 6.8 5.0 3.1 0.90
Picea abies* KU 1 0.003 6.2 6.9 3.8 0.97
Dead 2007–2019 - 145 1.831 12.7 - - -

models from the spruce stand were used.

During preparations for field measurements in the pine stand we identified one tree that was measured in 2007, but due to error had its location coordinates determined outside the test site. The tree was left out from the report by Kuusk et al. (2013). Here the tree is included and therefore for 2007 the number of trees in the upper layer is 1116 (Table 1). The pine stand (Figure 5) has the simplest structure of the three stands. There is basically only one layer of Scots pine trees and few small trees that matched the minimum d rule. As in the pine and spruce stand, we can see an increase in basal area, mean tree diameter at breast height and stand mean height. The number of trees decreased with smaller trees having a higher probability of dying (Figure 6).

Figure 5.

Map of alive trees in RAMI pine stand in 2019. The symbols are scaled according to tree size. Brown corresponds to pine, cyan to birch, magenta to spruce.

Joonis 5. RAMI männiku kasvavate puude kaart aastal 2019. Sümbolid on skaleeritud kujutamaks puude suurust, värvid vastavad metsakorralduse juhendile.

Figure 6.

Changes in stem breast height diameter distribution in the pine stand. Label (d) is for trees that died between two measurements made in 2007 and 2019.

Joonis 6. Männiku puude diameetrijaotuse muutus. Ajavahemikus 2007–2019 surnud puud (d) on eraldi välja toodud.

Discussion and conclusion

The three sample plots in Järvselja forest district are similar to the examples in Harvard forest (Eisen & Barker Plotkin, 2015) and to the fiducial reference site in Speulderbos that was established for the validation of satellite measurements-based predictions of forest biophysical variables (Brede et al., 2016). Although for the validation of methods for a wide area map (Dostálová et al., 2018) construction the number of validation observations is more important (Copernicus HRL, 2019) than the sample plot size and tree-level detailed data, large sample plots are better suitable for experiments like RAMI described by Widlowski et al. (2015). Large sample plots are the only means to study the impact of sample plot size on the estimation of forest inventory variables regarding tree location patterns (Maleki & Kiviste, 2015) and also for testing global estimates of forest biophysical products like MODIS BRDF (Pisek et al., 2015).

Our repeated measurements in the three sample plots showed that stand basal area, stand height and mean tree diameter at breast height have been increasing since 2007. The smallest increments were observed in the pine stand which is explained by the poor growth conditions i.e., excess water and limited availability of nutrients in the thick peat soil layer. An interesting finding in the spruce stand was that crown diameter of the spruce trees decreased compared to 2007. As interpretation errors in tree crown outer boundary estimation may be one cause to the result, we expect more solid evidence from terrestrial laser scanning data from 2013 (Kuusk et al., 2015) and 2019 measurements.

Figure 1.

Map of live trees in RAMI birch stand in 2019. The symbols are scaled according to tree size. Cyan corresponds to birch, magenta to spruce, blue-violet to black alder, green to European aspen and grey to other species.Joonis 1. RAMI kaasiku kasvavate puude kaart aastal 2019. Sümbolid on skaleeritud kujutamaks puude suurust, värvid vastavad metsakorralduse juhendile.
Map of live trees in RAMI birch stand in 2019. The symbols are scaled according to tree size. Cyan corresponds to birch, magenta to spruce, blue-violet to black alder, green to European aspen and grey to other species.Joonis 1. RAMI kaasiku kasvavate puude kaart aastal 2019. Sümbolid on skaleeritud kujutamaks puude suurust, värvid vastavad metsakorralduse juhendile.

Figure 2.

Changes in stem breast height diameter distribution in the birch stand. Label (d) is for the trees that died between two measurements made in 2007 and 2019.Joonis 2. Kaasiku puude diameetrijaotuse muutus. Ajavahemikus 2007–2019 surnud puud (d) on eraldi välja toodud.
Changes in stem breast height diameter distribution in the birch stand. Label (d) is for the trees that died between two measurements made in 2007 and 2019.Joonis 2. Kaasiku puude diameetrijaotuse muutus. Ajavahemikus 2007–2019 surnud puud (d) on eraldi välja toodud.

Figure 3.

Map of alive trees in RAMI spruce stand in 2019. The symbols are scaled according to tree size. Magenta corresponds to spruce and cyan corresponds to birch.Joonis 3. RAMI kuusiku kasvavate puude kaart aastal 2019. Sümbolid on skaleeritud kujutamaks puude suurust, värvid vastavad metsakorralduse juhendile.
Map of alive trees in RAMI spruce stand in 2019. The symbols are scaled according to tree size. Magenta corresponds to spruce and cyan corresponds to birch.Joonis 3. RAMI kuusiku kasvavate puude kaart aastal 2019. Sümbolid on skaleeritud kujutamaks puude suurust, värvid vastavad metsakorralduse juhendile.

Figure 4.

Changes in stem breast height diameter distribution in the spruce stand. Label (d) is for trees that died between two measurements made in 2007 and 2019.Joonis 4. Kuusiku puude diameetrijaotuse muutus. Ajavahemikus 2007–2019 surnud puud (d) on eraldi välja toodud.
Changes in stem breast height diameter distribution in the spruce stand. Label (d) is for trees that died between two measurements made in 2007 and 2019.Joonis 4. Kuusiku puude diameetrijaotuse muutus. Ajavahemikus 2007–2019 surnud puud (d) on eraldi välja toodud.

Figure 5.

Map of alive trees in RAMI pine stand in 2019. The symbols are scaled according to tree size. Brown corresponds to pine, cyan to birch, magenta to spruce.Joonis 5. RAMI männiku kasvavate puude kaart aastal 2019. Sümbolid on skaleeritud kujutamaks puude suurust, värvid vastavad metsakorralduse juhendile.
Map of alive trees in RAMI pine stand in 2019. The symbols are scaled according to tree size. Brown corresponds to pine, cyan to birch, magenta to spruce.Joonis 5. RAMI männiku kasvavate puude kaart aastal 2019. Sümbolid on skaleeritud kujutamaks puude suurust, värvid vastavad metsakorralduse juhendile.

Figure 6.

Changes in stem breast height diameter distribution in the pine stand. Label (d) is for trees that died between two measurements made in 2007 and 2019.Joonis 6. Männiku puude diameetrijaotuse muutus. Ajavahemikus 2007–2019 surnud puud (d) on eraldi välja toodud.
Changes in stem breast height diameter distribution in the pine stand. Label (d) is for trees that died between two measurements made in 2007 and 2019.Joonis 6. Männiku puude diameetrijaotuse muutus. Ajavahemikus 2007–2019 surnud puud (d) on eraldi välja toodud.

RAMI birch stand at Järvselja, Estonia 15 August 2018
RAMI birch stand at Järvselja, Estonia 15 August 2018

RAMI spruce stand at Järvselja, Estonia 01 August 2019
RAMI spruce stand at Järvselja, Estonia 01 August 2019

RAMI pine stand at Järvselja, Estonia 01 August 2019
RAMI pine stand at Järvselja, Estonia 01 August 2019

Corner coordinates (EPSG:3301) of the test sites measured with differential GPS Tabel 1. Katsealade nurgakoordinaadid Eesti põhikaardi süsteemis

Corner Xlocal ylocal XEPSG:3301 yEPSG:3301
Pine1 0 0 693110.5 6468117.1
Pine2 0 100 693121.6 6468216.7
Pine3 100 100 693220.8 6468205.6
Pine4 100 0 693210.1 6468105.9
Spruce1 0 0 690832.1 6466197.9
Spruce2 0 100 690814.5 6466296.3
Spruce3 100 100 690913.1 6466313.8
Spruce4 100 0 690930.6 6466215.4
Birch1 0 0 695299.9 6464769.0
Birch2 0 100 695280.7 6464867.2
Birch3 100 100 695378.8 6464886.6
Birch4 100 0 695397.7 6464788.0

Spruce stand summary of forest inventory 2007 and 2019. Tabel 3. Kuusiku 2007. ja 2019. aasta takseerandmete kokkuvõte.

Species Code N G D H Lcr Rcr
2007 inventory, upper layer
Populus tremula HB 2 0.052 18.2 25.2 7.1 1.51
Betula pendula KS 143 3.607 17.9 24.7 8.7 1.52
Picea abies KU 624 27.04 23.5 23.8 12.0 1.81
Alnus glutinosa LM 3 0.097 20.3 22.6 9.6 2.05
Pinus sylvestris L. MA 2 0.109 26.3 24.5 10.4 2.11
2007 inventory, second layer
Betula pendula KS 152 1.024 9.3 18.1 4.9 0.92
Picea abies KU 517 5.015 11.1 14.7 6.2 1.17
2007 inventory, regeneration layer
Picea abies KU 89 0.188 5.2 5.7 2.8 1.09
Picea abies KU 157 0.586 6.9 9.1 3.5 1.10
2019 inventory, upper layer
Populus tremula HB 2 0.064 20.2 27.3 6.6 1.39
Betula pendula KS 132 4.489 20.8 28.0 10.2 1.67
Picea abies KU 585 30.61 25.8 26.7 12.1 1.57
Alnus glutinosa LM 3 0.111 21.7 24.4 12.3 2.12
Pinus sylvestris MA 2 0.139 29.7 27.2 13.4 2.70
2019 inventory, second layer
Betula pendula KS 45 0.494 11.8 23.1 5.2 0.93
Picea abies KU 375 4.198 11.9 16.4 7.1 1.04
2019 inventory, regeneration layer
Picea abies KU 87 0.248 6.0 7.2 3.2 0.92
Picea abies KU 70 0.326 7.7 11.7 4.8 0.92
Dead 2007–2019 - 394 1.861 7.8 - - -

Birch stand summary of forest inventory 2007 and 2019. Notations are explained under table. Tabel 2. Kaasiku 2007. ja 2019. aasta takseerandmete kokkuvõte.

Species Code N G D H Lcr Rcr
2007 inventory, upper layer
Populus tremula L. HB 78 2.848 21.6 27.5 9.4 1.95
Betula pendula Roth KS 399 13.44 20.7 26.9 9.4 1.63
Alnus glutinosa (L.) Gaertn. LM 176 6.921 22.4 23.8 9.8 2.04
Salix spp. PJ 1 0.044 23.7 24.0 9.9 1.96
2007 inventory, second layer
Ulmus glabra Huds. JA 1 0.010 11.3 15.9 8.1 0.99
Betula pendula KS 66 0.567 10.5 18.2 5.8 0.99
Alnus glutinosa LM 20 0.271 13.1 17.9 8.5 1.40
Tilia cordata PN 205 2.622 12.8 16.5 9.0 1.93
Fraxinus excelsior SA 30 0.281 10.9 17.6 9.2 1.64
Acer platanoides VA 16 0.159 11.2 16.3 8.5 1.85
2007 inventory, regeneration layer
Picea abies (L.) H. Karst. KU 39 0.245 8.9 10.3 4.8 1.16
2019 inventory, upper layer
Populus tremula HB 64 4.129 28.7 31.8 10.7 2.30
Betula pendula KS 342 15.44 24.0 29.4 11.5 1.97
Alnus glutinosa LM 159 8.654 26.3 26.4 13.1 2.27
2019 inventory, second layer
Ulmus glabra JA 1 0.015 13.8 17.3 11.0 2.03
Betula pendula KS 27 0.275 11.4 19.7 8.0 1.20
Alnus glutinosa LM 18 0.318 15.0 20.6 10.7 1.65
Tilia cordata PN 264 4.369 14.5 20.2 13.0 2.13
Fraxinus excelsior SA 18 0.263 13.6 20.4 12.3 2.12
Acer platanoides VA 20 0.289 13.6 18.7 12.5 2.16
2019 inventory, regeneration layer
Picea abies KU 53 0.511 11.1 13.4 11.6 1.54
2019 inventory, dead trees
Dead 2007–2019 - 159 1.349 10.4 - - -

Summary of forest inventory 2007 and 2019 of the pine stand. Tabel 4. Männiku 2007. ja 2019. aasta takseerandmete kokkuvõte.

Species Code N G D H Lcr Rcr
2007 inventory, upper layer
Pinus sylvestris MA 1116 28.25 18 16.1 4.5 1.52
2007 inventory, regeneration layer
Betula pendula KS 6 0.014 5.5 4.1 2.9 0.78
Picea abies* KU 1 0.002 5.0 5.0 1.8 1.09
2019 inventory, upper layer
Pinus sylvestris MA 971 29.09 19.5 17.4 4.6 1.53
2019 inventory, regeneration layer
Betula pendula KS 6 0.022 6.8 5.0 3.1 0.90
Picea abies* KU 1 0.003 6.2 6.9 3.8 0.97
Dead 2007–2019 - 145 1.831 12.7 - - -

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