Current issue: 53(2)

Under compilation: 53(3)

Impact factor 1.683
5-year impact factor 1.950
Silva Fennica 1926-1997
1990-1997
1980-1989
1970-1979
1960-1969
Acta Forestalia Fennica
1953-1968
1933-1952
1913-1932

Articles containing the keyword 'variation'.

Category: Research article

article id 10076, category Research article
Tore Skrøppa, Arne Steffenrem. (2019). Genetic variation in phenology and growth among and within Norway spruce populations from two altitudinal transects in Mid-Norway. Silva Fennica vol. 53 no. 1 article id 10076. https://doi.org/10.14214/sf.10076
Highlights: Norway spruce populations distributed along each of two altitudinal transects showed strong clinal relationships between the annual mean temperatures of the sites of the populations and height and phenology traits in short term tests and height in field trials; Large variation was present among families within populations for height and phenology traits and with a wider range within than among populations; Correlation patterns among traits were different for provenances and families.

Progenies from open pollinated cones collected in natural populations of Norway spruce (Picea abies (L.) Karst.) distributed along two altitudinal transects in Mid-Norway were tested in the nursery, in short term tests and in long-term field trials. The populations showed clinal variation related to the mean annual temperatures of the populations, with the earliest bud flush and cessation of shoot elongation and lowest height at age nine years for the high altitude populations. Within population variation was considerable as the narrow sense heritability for these traits was 0.67, 0.31 and 0.09 in one transect and 0.55, 0.18 and 0.14 in the other transect, respectively. Lammas shoots occurred in the short term trials with large variation in frequency between years. There was significant family variation for this trait, but also interactions between populations and year. The variance within populations was considerably larger in the populations from low altitude compared to the high-altitude populations. Significant genetic correlations between height and phenology traits and damage scores indicate that families flushing early and ceasing growth late were taller. Taller families also had higher frequencies of damages. Selection of the top 20% families for height growth in short term tests at age nine years gave a simulated gain of 11% increased height growth at age 18 years in long term trials at altitudes similar to those of origin of the populations. The gain was negative when high altitude populations were selected based on testing in the lowland.

  • Skrøppa, Norwegian Institute of Bioeconomy Research, P.O. Box 115, 1431 Ås, Norway ORCID ID:E-mail: tore.skroppa@nibio.no (email)
  • Steffenrem, ORCID ID:E-mail:
article id 10000, category Research article
Hamed Yousefzadeh, Rasta Rajaei, Anna Jasińska, Łukasz Walas, Yann Fragnière, Gregor Kozlowski. (2018). Genetic diversity and differentiation of the riparian relict tree Pterocarya fraxinifolia (Juglandaceae) along altitudinal gradients in the Hyrcanian forest (Iran). Silva Fennica vol. 52 no. 5 article id 10000. https://doi.org/10.14214/sf.10000
Highlights: The Caucasian wingnut (Pterocarya fraxinifolia Spach) is an emblematic and relict riparian tree with limited distribution in Hyrcanian forest which investigating its genetic population structure and diversity along altitudinal gradients, and migration patterns are novel; We concluded that rivers are the main seed dispersal vector among P. fraxinifolia populations and there was no trend from upstream to downstream; The high level of gene flow and uniform genetic diversity along each river system suggest the “classical” metapopulation structure of the species.

Riparian trees, especially relict trees, are attractive and important for research to understand both past and recent biogeographical and evolutionary processes. Our work is the first study to elucidate the genetic diversity and spatial genetic structure of the canopy-dominating riparian Pterocarya fraxinifolia (Juglandaceae) along two altitudinal gradients in different river systems of the Hyrcanian forest, which is one of the most important refugium of relict trees in Western Eurasia. Altitudinal gradients were chosen along two river systems at 100, 400 and 900 m a.s.l. Leaf samples were collected from 116 trees, and the genetic diversity was evaluated with eight SSR markers. Overall, 39 alleles were identified for all of the populations studied. The observed heterozygosity (Ho) varied from 0.79 to 0.87 (with a mean of 0.83). The results of the AMOVA analysis indicated that the variation within populations was 88%, whereas the variation among populations was 12% for all of the gradients. A structure analysis indicated that 93% of the trees were grouped in the same gradient. The genetic distance based on Fst confirmed the structure result and indicated a high rate of gene flow among the investigated populations. Based on high gene flow (low differentiation of the population along the same river) and the clearly distinct genetic structure of the investigated gradients, it can be concluded that rivers are the main seed dispersal vector among P. fraxinifolia populations. The genetic diversity of P. fraxinifolia did not show any trend from upstream to downstream. The high level of gene flow and uniform genetic diversity along each river suggest the “classical” metapopulation structure of the species.

  • Yousefzadeh, Department of Environmental Science, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, Mazandaran, Iran ORCID ID:E-mail: h.yousefzadeh@modares.ac.ir (email)
  • Rajaei, Department of Forestry, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, Mazandaran, Iran ORCID ID:E-mail: r.rajaei@modares.ac.ir
  • Jasińska, Laboratory of Systematics and Geography, Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, PL-62-035 Kornik, Poland ORCID ID:E-mail: jasiak9@wp.pl
  • Walas, Laboratory of Systematics and Geography, Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, PL-62-035 Kornik, Poland ORCID ID:E-mail: lukaswalas@wp.pl
  • Fragnière, Department of Biology and Botanic Garden, University of Fribourg, Chemin du Musée 10, CH-1700 Fribourg, Switzerland ORCID ID:E-mail: yann.fragniere@unifr.ch
  • Kozlowski, Department of Biology and Botanic Garden, University of Fribourg, Chemin du Musée 10, CH-1700 Fribourg, Switzerland; Natural History Museum Fribourg, Chemin du Musée 6, CH-1700 Fribourg, Switzerland ORCID ID:E-mail: gregor.kozlowski@unifr.ch
article id 9938, category Research article
Jyrki Hytönen, Egbert Beuker, Anneli Viherä-Aarnio. (2018). Clonal variation in basic density, moisture content and heating value of wood, bark and branches in hybrid aspen. Silva Fennica vol. 52 no. 2 article id 9938. https://doi.org/10.14214/sf.9938
Highlights: Hybrid aspen clones differed in their moisture content, ash content, basic density and heating value; Stem wood had lower ash content, basic density and effective heating value than stem bark; There was significant vertical variation in wood and bark along the stem in moisture content and basic density.

Hybrid aspen (Populus tremula × P. tremuloides) is one of the fastest growing tree species in Finland. During the mid-1990s, a breeding programme was started with the aim of selecting clones that were superior in producing pulpwood. Hybrid aspen can also be grown as a short-rotation crop for bioenergy. To study clonal variation in wood and bark properties, seven clones were selected from a 12-year-old field trial located in southern Finland. From each clone, five trees were harvested and samples were taken from stem wood, stem bark and branches to determine basic density, effective heating value, moisture and ash content. Vertical within-tree variation in moisture content and basic density was also studied. The differences between clones were significant for almost all studied properties. For all studied properties there was a significant difference between wood and bark. Wood had lower ash content (0.5% vs. 3.9%), basic density (378 kg m–3 vs. 450 kg m–3) and effective heating value (18.26 MJ kg–1 vs. 19.24 MJ kg–1), but higher moisture content (55% vs. 49%) than bark. The values for branches were intermediate. These results suggest that the properties of hybrid aspen important for energy use could be improved by clonal selection. However, selecting clones based on fast growth only may be challenging since it may lead to a decrease in hybrid aspen wood density.

  • Hytönen, Natural Resources Institute Finland (Luke), Natural resources, Teknologiakatu 7, FI-67100 Kokkola, Finland ORCID ID:E-mail: jyrki.hytonen@luke.fi (email)
  • Beuker, Natural Resources Institute Finland (Luke), Production systems, Vipusenkuja 6, FI-57200 Savonlinna, Finland ORCID ID:E-mail: egbert.beuker@luke.fi
  • Viherä-Aarnio, Natural Resources Institute Finland (Luke), Production systems, Latokartanonkaari 9, FI-00790 Helsinki, Finland ORCID ID:E-mail: anneli.vihera-aarnio@luke.fi
article id 7001, category Research article
Fei-Fei Zhai, Jun-Xiang Liu, Zhen-Jian Li, Jin-Mei Mao, Yong-Qiang Qian, Lei Han, Zhen-Yuan Sun. (2017). Assessing genetic diversity and population structure of Salix viminalis across Ergun and West Liao basin. Silva Fennica vol. 51 no. 3 article id 7001. https://doi.org/10.14214/sf.7001
Highlights: High genetic diversity and moderate population differentiation were detected in twelve Salix viminalis populations; Populations from Ergun basin presented higher genetic diversity than populations from West Liao basin; Populations with short distances presented low differentiation.

Salix viminalis L. is an important shrub that has potential for use as a bioenergy crop, for phytoremediation of heavy metal contaminated soil and sewage sludge treatment. It is mainly distributed in the northeast of China, but the species has not yet been used a resource here. We examined the genetic diversity and population structure of populations from the Ergun basin and West Liao basin using 20 microsatellite markers. A high level of genetic diversity (Na = 16.45, He = 0.742) was detected for S. viminalis, and populations from the Ergun basin exhibited higher genetic diversity and private alleles numbers than the West Liao basin. The 12 populations could be divided into two clusters by both Bayesian analysis and UPGMA clustering which were consistent with the populations derived from the two basins. Moderate population differentiation (FST = 0.076) was shown in S. viminalis, and AMOVA analysis confirmed that most of the genetic variation (86.13%) was attributed to individual differences within populations, while 11.49% was attributed to differences between basins and 2.38% to differences within each basin. Significant correlations of FST/(1–FST) with log (geographic distance) among 12 populations (r = 0.634, p < 0.00) and 10 populations within the Ergun basin (r = 0.482, p = 0.0002) indicated that geographical distance was the principal factor influencing genetic structure. As most of genetic variation exist within populations, so protection measures should be focused on populations with higher genetic diversity and unique alleles, such as Tuli, Mordaga downstream, Zhadun1 and Genhe.

  • Zhai, State Key Laboratory of Tree Genetics and Breeding; Research Institute of Forestry, Chinese Academy of Forestry; Key Laboratory of Tree Breeding and Cultivation, State Forestry Administration, Haidian District, Beijing, 10091, PR China; School of Architectural and Artistic Design, Henan Polytechnic University, Century Avenue, Jiaozuo, Henan, 454000, PR China ORCID ID:E-mail: lkyzff@163.com
  • Liu, State Key Laboratory of Tree Genetics and Breeding; Research Institute of Forestry, Chinese Academy of Forestry; Key Laboratory of Tree Breeding and Cultivation, State Forestry Administration, Haidian District, Beijing, 10091, PR China ORCID ID:E-mail: liu-jx295@163.com
  • Li, State Key Laboratory of Tree Genetics and Breeding; Research Institute of Forestry, Chinese Academy of Forestry; Key Laboratory of Tree Breeding and Cultivation, State Forestry Administration, Haidian District, Beijing, 10091, PR China ORCID ID:E-mail: zhenjianli@163.com
  • Mao, State Key Laboratory of Tree Genetics and Breeding; Research Institute of Forestry, Chinese Academy of Forestry; Key Laboratory of Tree Breeding and Cultivation, State Forestry Administration, Haidian District, Beijing, 10091, PR China; Research Institute of Economic Forest, Xinjiang Academy of Forestry, Anjunanlu, Urumqi, Xinjiang, PR China ORCID ID:E-mail: 350512173@qq.com
  • Qian, State Key Laboratory of Tree Genetics and Breeding; Research Institute of Forestry, Chinese Academy of Forestry; Key Laboratory of Tree Breeding and Cultivation, State Forestry Administration, Haidian District, Beijing, 10091, PR China ORCID ID:E-mail: qianyq@caf.ac.cn
  • Han, State Key Laboratory of Tree Genetics and Breeding; Research Institute of Forestry, Chinese Academy of Forestry; Key Laboratory of Tree Breeding and Cultivation, State Forestry Administration, Haidian District, Beijing, 10091, PR China ORCID ID:E-mail: hdd@caf.ac.cn
  • Sun, State Key Laboratory of Tree Genetics and Breeding; Research Institute of Forestry, Chinese Academy of Forestry; Key Laboratory of Tree Breeding and Cultivation, State Forestry Administration, Haidian District, Beijing, 10091, PR China ORCID ID:E-mail: lkyszy@126.com (email)
article id 1721, category Research article
Anna Hebda, Błażej Wójkiewicz, Witold Wachowiak. (2017). Genetic characteristics of Scots pine in Poland and reference populations based on nuclear and chloroplast microsatellite markers. Silva Fennica vol. 51 no. 2 article id 1721. https://doi.org/10.14214/sf.1721
Highlights: Similar genetic variation was found between Polish Scots pine populations from a wide variety of habitats based on nSSR and cpSSR markers; Homogeneity was observed in the genetic structures of Polish and Finnish populations from the continuous pine range; Genetic differentiation in microsatellite markers was identified only when populations from the central pine distribution were compared to the marginal stands.

Polymorphisms at a set of eighteen nuclear (nSSR) and chloroplast (cpSSR) microsatellite loci were investigated in sixteen populations of Scots pine (Pinus sylvestris L.) derived from the provenance trial experiment and representative of the species distribution range and climatic zones in Poland. The patterns of genetic variation were compared to the reference samples from the species distribution in Europe and Asia. A similar level of genetic variation and no evidence of population structure was found among the Polish stands. They showed genetic similarity and homogenous patterns of allelic frequency spectra compared to the Northern European populations. Those populations were genetically divergent compared to the marginal populations from Turkey, Spain and Scotland. The population structure patterns reflect the phylogeography of the species and the divergence of populations that most likely do not share recent history. As the analysed provenance trial populations from Poland are diverged in phenotypic traits but are genetically similar, they could be used to test for selection at genomic regions that influence variation in quantitative traits.

  • Hebda, University of Agriculture in Krakow, Faculty of Forestry, Institute of Forest Ecology and Silviculture, Department of Genetics and Forest Tree Breeding, 29 Listopada 46, 31-425 Kraków, Poland ORCID ID: http://orcid.org/0000-0002-3149-8644 E-mail: ana.hebda@gmail.com (email)
  • Wójkiewicz, Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035 Kórnik, Poland ORCID ID:E-mail: bwojkiew@man.poznan.pl
  • Wachowiak, Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035 Kórnik, Poland; Institute of Environmental Biology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland ORCID ID:E-mail: witoldw@man.poznan.pl
article id 1262, category Research article
Āris Jansons, Roberts Matisons, Māra Zadiņa, Linards Sisenis, Jānis Jansons. (2015). The effect of climatic factors on height increment of Scots pine in sites differing by continentality in Latvia. Silva Fennica vol. 49 no. 3 article id 1262. https://doi.org/10.14214/sf.1262
Highlights: Height increment-climate relationships of Scots pine were assessed using dendrochronological techniques; Annual height increment was significantly affected by climatic factors; In western Latvia, temperature in preceding summer mainly affected height increment; In eastern Latvia height increment was affected by previous autumn temperature; During the 20th century, the effect of climatic factors has altered likely dues to climate change.
Height growth of trees is a crucial parameter that influences the composition and productivity of forest stands and quality of timber; however, the relationships between annual height increment (HI) and climatic factors have been poorly studied. In this study, the effect of monthly mean temperature and precipitation sums on the HI of Scots pine in two sites in Latvia have been determined using dendrochronological techniques. Correlation and response function analyses were conducted for entire chronologies of HI and for 50-year intervals within them. Climatic factors significantly affected the HI of Scots pine; however, not only did the suite of significant factors differ between the sites, but the influence of these factors changed during the 20th century. In the site in western Latvia where climate is milder, temperature in the preceding summer was the main climatic determinant of HI. The effect of temperature in the dormant period and spring was significant during the first part of the 20th century, while the effect of temperature in the previous September and November has become significant since the second half of the 20th century. In the site in eastern Latvia where summers are hotter, HI has been affected by both temperature and water deficit related factors in the summer. However, since the later part of the 20th century, the effect of temperature in the previous October has intensified and become the main climatic determinant of HI.
  • Jansons,  LSFRI “Silava”, Rīgas str. 111, Salaspils, Latvia, LV2169 ORCID ID:E-mail: aris.jansons@silava.lv
  • Matisons,  LSFRI “Silava”, Rīgas str. 111, Salaspils, Latvia, LV2169 ORCID ID:E-mail: robism@inbox.lv (email)
  • Zadiņa,  LSFRI “Silava”, Rīgas str. 111, Salaspils, Latvia, LV2169 ORCID ID:E-mail: mara.zadina@silava.lv
  • Sisenis, LUA Forestry Faculty, Akadēmijas str. 11, Jelgava, Latvia ORCID ID:E-mail: linards.sisenis@llu.lv
  • Jansons, Forest Competence Centre, Dzērbenes str. 27, Riga, Latvia, LV1006 ORCID ID:E-mail: janis.jansons@silava.lv
article id 1141, category Research article
Isabel Miranda, Jorge Gominho, Helena Pereira. (2015). Heartwood, sapwood and bark variation in coppiced Eucalyptus globulus trees in 2nd rotation and comparison with the single-stem 1st rotation. Silva Fennica vol. 49 no. 1 article id 1141. https://doi.org/10.14214/sf.1141
Highlights: Coppiced E. globulus trees in the 2nd rotation have similar heartwood and sapwood development as single-stem trees in the 1st rotation; The initial tree planting density did not influence heartwood development of coppiced E. globulus trees; Heartwood diameter and height can be modelled with tree diameter and height respectively; Sapwood width is approximately constant within and between coppice and single-stem E. globulus trees.
Coppiced Eucalyptus globulus trees with 18 years in a 2nd rotation were analysed in relation to heartwood, sapwood and bark content taking into account the effect of the initial planting density by using a spacing trial. A total of 25 stumps, with a variable number of stems per stump from 1 to 3, were analysed. Comparison was made to the previous 1st rotation single stem trees, also harvested at 18 years. In the 2nd rotation, the stump density did not significantly affect stem height and diameter, in opposition to the 1st rotation where spacing significantly impacted on tree dimensions. The effect of the initial planting density is somewhat lost in the coppiced stand in relation with i.e. the number of stems per stump. Heartwood was present in all the coppiced trees up to 49.9% of the total tree height and heartwood volume amounted to 38.9–51.7% of the total tree volume. Within the tree, heartwood content decreased from the base upwards, representing, on average, 54.1% at the base and decreasing to 5.1% at 15.3 m. The sapwood width remained relatively constant with an average radial width of approximately 2 cm. The average stem bark content of coppiced trees was 17.4% of the total stem volume. The comparison of heartwood and sapwood development in the coppiced trees did not show significant differences to the 1st rotation trees, nor did the initial spacing. Heartwood diameter could be modelled using the tree diameter both for 1st and 2nd rotation trees.
  • Miranda, Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade Lisboa, 1349-017 Lisboa, Portugal ORCID ID:E-mail: Imiranda@isa.ulisboa.pt
  • Gominho, Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade Lisboa, 1349-017 Lisboa, Portugal ORCID ID:E-mail: Jgominho@isa.utl.pt (email)
  • Pereira, Centro de Estudos Florestais, Instituto Superior de Agronomia, Universidade Lisboa, 1349-017 Lisboa, Portugal ORCID ID:E-mail: Hpereira@isa.utl.pt
article id 115, category Research article
Marjut Turtiainen, Kauko Salo, Olli Saastamoinen. (2011). Variations of yield and utilisation of bilberries (Vaccinium myrtillus L.) and cowberries (V. vitis-idaea L.) in Finland. Silva Fennica vol. 45 no. 2 article id 115. https://doi.org/10.14214/sf.115
So far, only rough estimates for the utilisation rates of wild berries in Finland have been available. One reason for this is that there has been a lack of empirical-knowledge-based studies concerning total yields of wild berries and their yield variations. This study had three aims: 1) total bilberry and cowberry yields of an average crop year were calibrated for different (abundant and poor) crop years using the inventory data on wild berries collected by the Finnish Forest Research Institute (1997–2008); 2) national utilisation rates of bilberries and cowberries were calculated for three different berry years 1997–1999; and 3) regional utilisation rates of these berry species were calculated for the year 1997. According to calculations, annual bilberry yields in Finland vary from 92 to 312 million kg. For cowberry, the range of variation in total berry yields is from 129 to 386 million kg. It was also found that approximately the same proportion of the total yield of bilberries (i.e. 5–6%) was collected between 1997 and 1999. Utilisation rates of cowberries were also quite constant varying from approximately 8% to nearly 10%. In 1997, bilberries and cowberries were utilised most intensively in the eastern parts of the country and in the Oulu-Kainuu region. The results of this present study describe the situation before the phenomenon of foreign pickers. It can be presumed that commercial wild berry picking by migrant collectors has so far affected both national and regional utilisation rates of wild berries.
  • Turtiainen, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland ORCID ID:E-mail: marjut.turtiainen@uef.fi (email)
  • Salo, Finnish Forest Research Institute, Joensuu Research Unit, Joensuu, Finland ORCID ID:E-mail:
  • Saastamoinen, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland ORCID ID:E-mail:
article id 152, category Research article
Torgny Persson, Bengt Andersson, Tore Ericsson. (2010). Relationship between autumn cold hardiness and field performance in northern Pinus sylvestris. Silva Fennica vol. 44 no. 2 article id 152. https://doi.org/10.14214/sf.152
Results from 3 artificial freezing tests (one-year-old seedlings) and 15 field trials (9- to 21-year old trees) of half-sib offspring from first generation Scots pine (Pinus sylvestris L.) plus-trees were used to estimate the amount of additive genetic variance for autumn cold hardiness and traits assessed in the field, and the genetic correlations between them. Cold hardiness of individual seedlings was scored visually, based on the discoloration of their needles after freezing in a climate chamber. The field traits analyzed were tree vitality, tree height, spike knot frequency, branch diameter, branch angle, stem straightness, and susceptibility to infection by the pathogenic fungi Phacidium infestans L., Gremmeniella abietina (Lagerb.) Morelet, Melampsora pinitorqua (Braun) Rostr. and Lophodermella sulcigena (Rostr.) Höhn. Narrow sense individual heritabilities varied between 0.30 and 0.54 for autumn cold hardiness, 0 and 0.18 for tree vitality, 0.07 and 0.41 for tree height, and 0.01 and 0.26 for the remaining traits. Based on the results of the artificial freeze tests, our estimates of additive genetic correlations indicate that while early selection for cold hardiness can improve seedling survival rates in the field, it may also reduce growth in mild environments. It also has minor effects on quality traits and attack by common fungal diseases. The results indicate that artificial freeze testing is an appropriate method for identifying suitable clones for establishing seed orchards to supply stock for the reforestation of regions with harsh environments.
  • Persson, Forestry Research Institute of Sweden, Sävar, Sweden ORCID ID:E-mail: torgny.persson@skogforsk.se (email)
  • Andersson, Forestry Research Institute of Sweden, Sävar, Sweden ORCID ID:E-mail:
  • Ericsson, Forestry Research Institute of Sweden, Sävar, Sweden ORCID ID:E-mail:
article id 233, category Research article
Raija Laiho, Sakari Sarkkola, Seppo Kaunisto, Jukka Laine, Kari Minkkinen. (2008). Macroscale variation in peat element concentrations in drained boreal peatland forests. Silva Fennica vol. 42 no. 4 article id 233. https://doi.org/10.14214/sf.233
Information on the variation in soil element concentrations at different spatial scales is needed for, e.g., designing efficient sampling strategies, upscaling the processes related to carbon cycling, and planning land use and management. In spite of intensive land use, such information concerning peat soils is still scarce. We analyzed the variation in peat mineral element concentrations in boreal peatland forests drained 50–60 years earlier. We wanted to quantify the proportions of variation deriving from differences between regions and peatland basins and from within-peatland heterogeneity, and to model the variation using relatively easily measurable site and soil characteristics. We utilized 878 peat samples representing the 0–20 cm layer and collected from 289 sites in 79 peatland basins. The sites represented three different drained peatland forest site types. The two strongest gradients in the element composition captured by principal component analysis were correlated with both the North-South gradient and the site type variation, and the East-West gradient. In general, most of the variation in the element concentrations was contributed by differences among peatland basins, and variation within the floristically determined sites. Most of the element concentrations were best modeled when either the bulk density or the ash content of the peat, or both, were used in addition to site type and geographical location. The explanatory power remained modest for most element concentrations. As for the P concentrations in soil, however, our models provide means for estimating a large part of the variation among drained pine mire sites.
  • Laiho, University of Helsinki, Department of Forest Ecology, FI-00014 University of Helsinki, Finland ORCID ID:E-mail: raija.laiho@helsinki.fi (email)
  • Sarkkola, Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland ORCID ID:E-mail:
  • Kaunisto, Finnish Forest Research Institute, Parkano Research Unit, Kaironiementie 54, FI-39700 Parkano, Finland ORCID ID:E-mail:
  • Laine, Finnish Forest Research Institute, Parkano Research Unit, Kaironiementie 54, FI-39700 Parkano, Finland ORCID ID:E-mail:
  • Minkkinen, University of Helsinki, Department of Forest Ecology, FI-00014 University of Helsinki, Finland ORCID ID:E-mail:
article id 248, category Research article
Tuula Jyske, Harri Mäkinen, Pekka Saranpää. (2008). Wood density within Norway spruce stems. Silva Fennica vol. 42 no. 3 article id 248. https://doi.org/10.14214/sf.248
We studied the variation in average wood density of annual rings, earlywood density, and latewood density in addition to ring width and latewood percentage within Norway spruce (Picea abies (L.) Karst.) stems from the pith to the bark, and from the stem base towards the stem apex. Moreover, the variation in wood density within annual rings was studied at the different heights and radial positions in the stem. The material consisted of 85 trees from central and south-eastern Finland. Variation between the annual rings accounted for 11–27% of the total variation in wood density. Only small differences (3–6%) in wood density were found between different heights in the stem. The largest (49–80%) variation in wood density was found within the annual rings. The difference in wood density between earlywood and latewood was smaller in the rings near the pith than in the outer rings. The increasing wood density from the pith outwards was related to increasing latewood density and latewood percentage, whereas the earlywood density increased only slightly from the pith outwards. In a given cambial age (i.e., given rings from the pith), the average wood density of annual rings increased with increasing stem height. In contrast, in the rings formed in the same calendar years (i.e., given rings from the bark), the average wood density of annual rings decreased with increasing stem height. The results of this study verify our knowledge of wood density variation and can further contribute to creating models to predict wood density.
  • Jyske, The Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland ORCID ID:E-mail: tuula.jyske@metla.fi (email)
  • Mäkinen, The Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland ORCID ID:E-mail:
  • Saranpää, The Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland ORCID ID:E-mail:
article id 248, category Research article
Tuula Jyske, Harri Mäkinen, Pekka Saranpää. (2008). Wood density within Norway spruce stems. Silva Fennica vol. 42 no. 3 article id 248. https://doi.org/10.14214/sf.248
We studied the variation in average wood density of annual rings, earlywood density, and latewood density in addition to ring width and latewood percentage within Norway spruce (Picea abies (L.) Karst.) stems from the pith to the bark, and from the stem base towards the stem apex. Moreover, the variation in wood density within annual rings was studied at the different heights and radial positions in the stem. The material consisted of 85 trees from central and south-eastern Finland. Variation between the annual rings accounted for 11–27% of the total variation in wood density. Only small differences (3–6%) in wood density were found between different heights in the stem. The largest (49–80%) variation in wood density was found within the annual rings. The difference in wood density between earlywood and latewood was smaller in the rings near the pith than in the outer rings. The increasing wood density from the pith outwards was related to increasing latewood density and latewood percentage, whereas the earlywood density increased only slightly from the pith outwards. In a given cambial age (i.e., given rings from the pith), the average wood density of annual rings increased with increasing stem height. In contrast, in the rings formed in the same calendar years (i.e., given rings from the bark), the average wood density of annual rings decreased with increasing stem height. The results of this study verify our knowledge of wood density variation and can further contribute to creating models to predict wood density.
  • Jyske, The Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland ORCID ID:E-mail: tuula.jyske@metla.fi (email)
  • Mäkinen, The Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland ORCID ID:E-mail:
  • Saranpää, The Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland ORCID ID:E-mail:
article id 251, category Research article
Lina R. Steinke, Andrea C. Premoli, Cintia P. Souto, Mikael Hedrén. (2008). Adaptive and neutral variation of the resprouter Nothofagus antarctica growing in distinct habitats in north-western Patagonia. Silva Fennica vol. 42 no. 2 article id 251. https://doi.org/10.14214/sf.251
N. antarctica occurs in the widest range of habitat types among all South American Notho–fagus. The aim of this study is to investigate adaptive responses by variation in morphological (tree form and leaf characters), and environmental traits (soils) of the polymorphic N. ant–arctica. Also we analyze the effect of genetic drift and limited gene flow in such predominantly apomict by means of neutral variation (isozymes). We studied four potentially different morphological variants each associated with a separate habitat 1) an arboreal variant growing in optimal environments; 2) a sparsely branched variant of temporarily flooded basins or flats; 3) a dwarf variant growing at high elevation, and 4) a shrub-like variant inhabiting matorral environments. The study was restricted latitudinally to Nahuel Huapi National Park, Argentina. For each habitat type we investigated two sites. Nothofagus antarctica shows locally occurring phenotypes. The forest and the high elevation variants were morphologically distinct from the matorral and the basin types. The latter were undistinguishable except for more profuse branching in the matorral type as a result of sprouting due to recent fires. Isozyme evidence indicates a great deal of within-population genetic diversity which is maintained by outcrossing and significant among-site divergence (FST = 18%) that reflects limited gene flow.The apparent high phenotypic and genetic variability in N. antarctica is due to both plasticity and genotypic effects as a result of stable population structure and long periods of isolation which may be reinforced by selection at diverse biotopes.
  • Steinke, Plant Ecology and Systematics, Lund University, Ecology Department, 223 62 Lund, Sweden ORCID ID:E-mail:
  • Premoli, Universidad Nacional del Comahue, Laboratorio Ecotono – CRUB, Quintral 1250, 8400 Bariloche, Argentina ORCID ID:E-mail: apremoli@crub.uncoma.edu.ar (email)
  • Souto, Universidad Nacional del Comahue, Laboratorio Ecotono – CRUB, Quintral 1250, 8400 Bariloche, Argentina ORCID ID:E-mail:
  • Hedrén, Plant Ecology and Systematics, Lund University, Ecology Department, 223 62 Lund, Sweden ORCID ID:E-mail:
article id 304, category Research article
Joanna Kosinska, Andrzej Lewandowski, Wladyslaw Chalupka. (2007). Genetic variability of Scots pine maternal populations and their progenies. Silva Fennica vol. 41 no. 1 article id 304. https://doi.org/10.14214/sf.304
The genetic variability of Scots pine was investigated in six populations from Poland representing two maternal populations and their natural and artificial progenies. Thirteen enzyme systems controlled by 25 allozyme loci were analyzed using starch gel electrophoresis. Progeny populations maintained a high and similar level of genetic variation to that observed in the maternal populations. As expected, much closer genetic relationships were observed between maternal populations and their respective progeny than between the two maternal populations themselves. Progeny populations had the same major alleles, but differed in the number of rare alleles. Therefore, probably not all rare alleles were transferred from the maternal stands to the progenies. In addition, new rare alleles appeared in the progeny populations, possibly as a result of external pollen flow into the maternal populations.
  • Kosinska, Department of Human Medical Genetics, Medical University of Warsaw, Oczki 1, 02-007 Warsaw, Poland ORCID ID:E-mail:
  • Lewandowski, Polish Academy of Sciences, Institute of Dendrology, 62-035 Kórnik, Poland ORCID ID:E-mail:
  • Chalupka, Polish Academy of Sciences, Institute of Dendrology, 62-035 Kórnik, Poland ORCID ID:E-mail:
article id 326, category Research article
Xuejiang Zhang, Helena Korpelainen, Chunyang Li. (2006). Microsatellite variation of Quercus aquifolioides populations at varying altitudes in the Wolong Natural Reserve of China. Silva Fennica vol. 40 no. 3 article id 326. https://doi.org/10.14214/sf.326
Genetic variation and differentiation were investigated among five natural populations of Quercus aquifolioides occurring along an altitudinal gradient that varied from 2000 to 3600 m above sea level in the Wolong Natural Reserve of China, by analyzing variation at six microsatellite loci. The results showed that the populations were characterized by relatively high intra-population variation with the average number of alleles equaling 11.33 per locus and the average expected heterozygosity (HE) being 0.779. The amount of genetic variation varied only little among populations, which suggests that the influence of altitude factors on microsatellite variation is limited. However, there is a significantly positive correlation between altitude and the number of low-frequency alleles (R2 = 0.97, P < 0.01), which indicates that Q. aquifolioides from high altitudes has more unique variation, possibly enabling adaptation to severe conditions. F statistics showed the presence of a slight deficiency of heterozygosity (FIS = 0.136) and a low level of differentiation among populations (FST = 0.066). The result of the cluster analysis demonstrated that the grouping of populations does not correspond to the altitude of the populations. Based on the available data, it is likely that the selective forces related to altitude are not strong enough to significantly differentiate the populations of Q. aquifolioides in terms of microsatellite variation.
  • Zhang, Chengdu Institute of Biology, Chinese Academy of Sciences, P.O. Box 416, Chengdu 610041, P. R. China; Graduate School of the Chinese Academy of Sciences, Beijing 100039, P. R. China ORCID ID:E-mail:
  • Korpelainen, Department of Applied Biology, P.O. Box 27, FI-00014 University of Helsinki, Finland ORCID ID:E-mail:
  • Li, Chengdu Institute of Biology, Chinese Academy of Sciences, P.O. Box 416, Chengdu 610041, P. R. China ORCID ID:E-mail: licy@cib.ac.cn
article id 364, category Research article
Timo Pukkala, Jari Miina. (2005). Optimising the management of a heterogeneous stand. Silva Fennica vol. 39 no. 4 article id 364. https://doi.org/10.14214/sf.364
The study presents a method for taking the heterogeneity of the stand into account in the optimisation of stand management. Heterogeneity refers to within-stand variation in stand density and/or other characteristics. A set of plots, corresponding to different sub-areas of the stand, represents the stand in calculations. Cuttings and other treatments of the plots are done simultaneously. The method was used to analyse how the optimal management depends on the heterogeneity of a Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) stand. The results supported the hypothesis that the heterogeneity of a stand decreases its optimal prior-thinning density. Also the remaining stand basal areas were lower in heterogeneous stands, especially in spruce. The effect of stand heterogeneity prior to the first commercial thinning still affected the timing of the second thinning, which had to be conducted earlier and at lower prior-thinning basal areas in heterogeneous stands. This happened despite the fact that the first thinning greatly decreased the within-stand variation in stand basal area. In addition, heterogeneity decreased the soil expectation value, net income and timber harvests.
  • Pukkala, University of Joensuu, Faculty of Forestry, P.O. Box 111, FI-80101 Joensuu, Finland ORCID ID:E-mail: timo.pukkala@joensuu.fi (email)
  • Miina, Finnish Forest Research Institute, Joensuu Research Unit, P.O. Box 68, FI-80101 Joensuu, Finland ORCID ID:E-mail:
article id 433, category Research article
Raija Laiho, Timo Penttilä, Jukka Laine. (2004). Variation in soil nutrient concentrations and bulk density within peatland forest sites. Silva Fennica vol. 38 no. 1 article id 433. https://doi.org/10.14214/sf.433
The within-site variability of soil characteristics on sites with different soil types remains poorly quantified, although this information is crucial for the success of research on soil properties, and especially for monitoring soil properties over time. We used coefficients of variation and multilevel variance component models to examine the within-site variation of soil (0–30 cm) mineral nutrient concentrations (P, K, Ca, Mg, Fe, mg g–1; Mn, Zn, mg g–1) and bulk density (kg m–3) on boreal deep-peat sites. We then evaluated the reliability of the site-level estimates (sample means) obtained using different sampling intensities (numbers of samples per site). Our 11 sites represented a single original site type within the oligotrophic nutrient level. Two of the sites were undrained while the rest had been drained for forestry at different points in time. Overall, P concentrations showed the smallest and Mn concentrations the largest within-site variation. The sampling depth contributed more than 50% of the total variance in all other characteristics except the concentrations of P and Fe, and bulk density. The variance proportions of peatland basin, site (within basin), and sampling location (within site) varied by sampling depth for most soil characteristics. The estimates obtained when using a certain number of samples per site were always more reliable for the 0–30 cm layer’s composite samples than for any single 10-cm layer at any depth sampled. On average, it was found that between 4 (P) and some 200 (Mn) samples per site would be needed for the estimates to have a theoretical 10% maximum deviation.
  • Laiho, Univ. of Helsinki, Dept. of Forest Ecology, Peatland Ecology Group, P.O. Box 27, FIN-00014 University of Helsinki, Finland ORCID ID:E-mail: raija.laiho@helsinki.fi (email)
  • Penttilä, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland ORCID ID:E-mail:
  • Laine, Univ. of Helsinki, Dept. of Forest Ecology, Peatland Ecology Group, P.O. Box 27, FIN-00014 University of Helsinki, Finland ORCID ID:E-mail:
article id 554, category Research article
Seppo Rouvinen, Timo Kuuluvainen, Juha Siitonen. (2002). Tree mortality in a Pinus sylvestris dominated boreal forest landscape in Vienansalo wilderness, eastern Fennoscandia. Silva Fennica vol. 36 no. 1 article id 554. https://doi.org/10.14214/sf.554
Tree mortality and its causes and spatial pattern were examined along four transects (width 40 m, length 2550–3960 m), with a total length of 12 190 m and area of 48.8 ha, in a Pinus sylvestris L. dominated, boreal forest landscape. Tree mortality was determined within a time window of 3 years by identifying those trees (dbh ≥ 10 cm) along the transects that fitted into one of the three categories: 1) current mortality: trees that had died during the year of survey (1998), 2) recent mortality: trees that had died during the year (1997) before the survey year, and 3) predicted mortality: trees that were expected to die during the year (1999) following the survey year. Long-term tree mortality was studied on 10 plots (20 m x 100 m) by dating 87 dead trees using dendrochronological methods. The mean current mortality was 1.4 m3 ha–1 (3.7 trees ha–1). Both the recent and predicted mortalities were also 1.4 m3 ha–1. Mortality was, on the average, higher on peatlands than on mineral soils. The highest mortality was found within an area recently flooded by beavers. Over half of the examined trees (52%) were judged to die without any visible signs of an external abiotic cause. At the landscape scale, tree mortality was continuous although somewhat aggregated in space. Of the 66 dated standing dead Pinus trees, 23 (35%) had died during the 19th century and two during the 18th century, demonstrating that dead Pinus can remain standing for long periods of time before falling. Our results show that autogenic mortality of individual trees or small groups of trees was the predominant mode of disturbance in this Pinus dominated landscape.
  • Rouvinen, University of Joensuu, Faculty of Forestry, P.O. Box 111, FIN-80101 Joensuu, Finland ORCID ID:E-mail: seppo.rouvinen@forest.joensuu.fi (email)
  • Kuuluvainen, University of Helsinki, Department of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland ORCID ID:E-mail:
  • Siitonen, Finnish Forest Research Institute, P.O. Box 18, FIN-01301 Vantaa, Finland ORCID ID:E-mail: juha.siitonen@metla.fi
article id 576, category Research article
Anneli Viherä-Aarnio, Pirkko Velling. (2001). Micropropagated silver birches (Betula pendula) in the field – performance and clonal differences. Silva Fennica vol. 35 no. 4 article id 576. https://doi.org/10.14214/sf.576
Micropropagated and seed-born silver birches (Betula pendula Roth) were compared for survival, height growth and occurrence of biotic damage (voles, hares, mooses, stem lesions and cankers) in field trials in southern Finland. The material consisted of 11 clones and 10 different lots of seedlings growing in 10 field trials, established in clear-cut forest cultivation areas. The plants were 6–7 years old. The micropropagated and seed-born material types did not significantly differ from each other as regards survival, height growth and frequencies of damage caused by biotic agents. Large and significant differences were, however, detected in survival, height and frequencies of all types of biotic damage between single clones. Careful selection and testing of birch clones in field conditions is recommended before wide-scale commercial micropropagation and practical forest cultivation takes place.
  • Viherä-Aarnio, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box. 18, FIN-01301 Vantaa, Finland ORCID ID:E-mail: anneli.vihera-aarnio@metla.fi (email)
  • Velling, Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box. 18, FIN-01301 Vantaa, Finland ORCID ID:E-mail:
article id 606, category Research article
Pekka Leskinen, Jyrki Kangas. (2001). Modelling future timber price development by using expert judgments and time series analysis. Silva Fennica vol. 35 no. 1 article id 606. https://doi.org/10.14214/sf.606
Timber prices belong to the most important variables affecting the optimality of forest management. On the other hand, forecasting of timber prices is very uncertain. One difficulty when using past time series data in forecasting future timber price development is the possibility of changes in the markets and in the society at large. Expert knowledge can be applied in forecasting of timber prices as information additional to that provided by time series modelling. This paper presents an approach utilising both time series data and expert judgments in modelling future timber prices. A time series model is used as the basis for the approach. Parameters describing future timber price trends, variation in future timber prices, and the probabilities of price peaks taking place in the future are estimated with expert judgments as the basis. A case study involving 12 experts was carried out in Finland, and models were estimated for all the six major timber assortments in the country. The model produced can be utilised in the optimisation calculations of forest planning.
  • Leskinen, Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland ORCID ID:E-mail: pekka.leskinen@metla.fi (email)
  • Kangas, Finnish Forest Research Institute, Kannus Research Station, P.O. Box 44, FIN-69101 Kannus, Finland ORCID ID:E-mail:
article id 601, category Research article
Ricardo Alía, Javier Moro-Serrano, Eduardo Notivol. (2001). Genetic variability of Scots pine (Pinus sylvestris) provenances in Spain: growth traits and survival. Silva Fennica vol. 35 no. 1 article id 601. https://doi.org/10.14214/sf.601
Plants obtained from seed of 16 Spanish and 6 German provenances of Scots pine (Pinus sylvestris L.) were installed at five trial sites distributed throughout the natural range of the species in Spain. Five years after planting (7 years of age) the experimental material was measured for total height, diameter, number of twigs at the fourth year whorl and survival. The analysis confirmed that the rate of height growth of the Spanish is lower than that of the German provenances, whereas for the other traits the best Spanish compare favourably with the Germans. Provenance by site interaction was very significant (P < 0.01) for most traits. Attempts to model the interaction of Spanish provenances on height by simultaneous introduction of some climatic and geographic covariates on both factors were not successful but a multiplicative model with one bilinear term was enough to provide a sensible explanation of this interaction. Usually, provenances closest to each trial site were found better adapted than more distant ones but some provenances of close origin presented a different behaviour. Processes of adaptation and selection of these ancient populations could be considered as the main factors to cause this interaction.
  • Alía, CIFOR-INIA, Unidad de Mejora Forestal, 28080 Madrid, Spain ORCID ID:E-mail:
  • Moro-Serrano, CIFOR-INIA, Unidad de Mejora Forestal, 28080 Madrid, Spain ORCID ID:E-mail: jmoro@inia.es (email)
  • Notivol, Unidad de Recursos Forestales, SIA-DGA, Ca de Montañana 179, 50080 Zaragoza, Spain ORCID ID:E-mail:

Category: Review article

article id 694, category Review article
Gösta Eriksson. (1998). Evolutionary forces influencing variation among populations of Pinus sylvestris. Silva Fennica vol. 32 no. 2 article id 694. https://doi.org/10.14214/sf.694
The evolutionary forces influencing genetic differentiation among populations are identified. Natural selection, random genetic drift, and mutations promote differentiation while phenotypic plasticity and gene flow delay or prevent differentiation. Evolution is a dynamic force which leads to instability and absence of any perfection in the adaptive process. Natural selection acts mainly on phenotypes and only indirectly on the components of important breeding traits. In the northern part of the distribution of Scots pine there is a large among- and within-population variation in survival. The high among-population variation occurs in spite of an assumed high gene flow. Biomass is a product of many components and it also shows a high population variation. Many markers are neutral and such markers will not reveal adaptive variation.
  • Eriksson, Swedish University of Agricultural Sciences, Department of Forest Genetics, Uppsala, Sweden ORCID ID:E-mail: gosta.eriksson@sgen.slu.se (email)

Category: Research note

article id 7798, category Research note
Jānis Liepiņš, Jānis Ivanovs, Andis Lazdiņš, Jurģis Jansons, Kaspars Liepiņš. (2017). Mapping of basic density within European aspen stems in Latvia. Silva Fennica vol. 51 no. 5 article id 7798. https://doi.org/10.14214/sf.7798
Highlights: Stem bark is significantly denser than wood and does not follow the same variation patterns along the stem; The main trend in radial variation of wood density was the increase from pith to bark; There is a weak relationship between mean basic density and commonly measured stand and tree parameters.

The objective of this study was to investigate basic density and its within-stem variation by studying 84 European aspen stems from 28 forest stands in Latvia. The studied forest stands covered all age classes from young stands to matured forests in representative growth conditions of European aspen. The densities of 2722 wood and 1022 bark specimens were measured from the sampled trees. Only the knot-free wood specimens without obvious wood defects were chosen for analyses. A map of basic density summarizing its radial and axial variations was constructed to show species-specific, within-stem variability and the relationships between density and tree and stand variables were examined. Stem wood and bark of the European aspen show different patterns of basic density variation along the tree stem. Wood density increases from pith to bark up to certain dimensions and shows a slight decrease afterwards. The weighted basic density of bark (446 ± 39.6 kg m–3) was higher than stem wood density (393 ± 30.4 kg m–3). Our results suggest that wood and bark density measurements obtained at breast height can be used for reliable estimation of the densities of whole-tree stem components, while tree parameters such as diameter at breast height (DBH), tree height and social status or stand parameters, including number of trees, basal area and age, are weak predictors in this context.

  • Liepiņš, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia ORCID ID:E-mail: janis.liepins@silava.lv (email)
  • Ivanovs, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia ORCID ID:E-mail: janis.ivanovs@silava.lv
  • Lazdiņš, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia ORCID ID:E-mail: andis.lazdins@silava.lv
  • Jansons, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia ORCID ID:E-mail: jurgis.jansons@silava.lv
  • Liepiņš, Latvian State Forest Research Institute “Silava”, 111 Rigas Str., LV 2169, Salaspils, Latvia ORCID ID:E-mail: kaspars.liepins@silava.lv
article id 268, category Research note
Adam Boratynski, Katarzyna Marcysiak, Amelia Lewandowska, Anna Jasinska, Grzegorz Iszkulo, Jaroslaw Burczyk. (2008). Differences in leaf morphology between Quercus petraea and Q. robur adult and young individuals. Silva Fennica vol. 42 no. 1 article id 268. https://doi.org/10.14214/sf.268
The characters of Quercus robur and Q. petraea leaves are of main taxonomic value and the adult trees of both species can be distinguished on them. However, young individuals, mostly seedlings but also saplings, are told to be undistinguishable or only partly distinguishable on the leaf morphology. The aim of the study was to verify this hypothesis on the basis of biometrical analyses of leaf characteristics of adults trees and saplings in two mixed oak woods, one located close to the north-eastern limit, the other about 400 km inside of the Q. petraea range in Poland. The analysis of discriminations and minimum spanning tree on the squares of Mahalanobis distances were analysed to find differences between Q. robur, Q. petraea and intermediate adults and saplings. The differences between saplings of Q. robur and Q. petraea were found lower than between adult trees. Nevertheless, the biometrical analysis confirmed determination of saplings in the field.
  • Boratynski, Polish Academy of Sciences, Institute of Dendrology, 5 Parkowa str., 62-035 Kórnik, Poland ORCID ID:E-mail: borata@man.poznan.pl (email)
  • Marcysiak, Kazimierz Wielki University, Institute of Biology and Environment Protection, 12 Ossolinskich str., 85-064 Bydgoszcz, Poland ORCID ID:E-mail:
  • Lewandowska, Kazimierz Wielki University, Institute of Biology and Environment Protection, 12 Ossolinskich str., 85-064 Bydgoszcz, Poland ORCID ID:E-mail:
  • Jasinska, Polish Academy of Sciences, Institute of Dendrology, 5 Parkowa str., 62-035 Kórnik, Poland ORCID ID:E-mail:
  • Iszkulo, Polish Academy of Sciences, Institute of Dendrology, 5 Parkowa str., 62-035 Kórnik, Poland ORCID ID:E-mail:
  • Burczyk, Kazimierz Wielki University, Institute of Biology and Environment Protection, 12 Ossolinskich str., 85-064 Bydgoszcz, Poland ORCID ID:E-mail:

Category: Article

article id 7173, category Article
Erkki Lähde. (1966). Studies on the respiration rate in the different parts of the root systems of pine and spruce seedlings and its variations during the growing season. Acta Forestalia Fennica vol. 81 no. 8 article id 7173. https://doi.org/10.14214/aff.7173

In this study an attempt was made to use manometric Warburg technique in studying the growing season variations in the respiration rates of the roots of 1–3-year-old seedlings of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.). The respiration rates in both short-roots and long-roots have also been investigated.

According to the results, respiration intensity was the greatest in Scots pine and Norway spruce short-roots but also considerable in the long-root tips at the points of elongation. When the oxygen uptake rate per weight unit in the pine short-roots is given value of 100, the rate in the long-root tips is 61 and in the basal area 36. The corresponding values for spruce are 100, 69 and 43. The relative carbon dioxide release rates are different for the basal parts of the long-roots: pine 53 and spruce 57, when the CO2 release from the short-roots is 100. The CO2 release rate in the basal parts of the long-roots is relatively greater than the oxygen uptake. The respiration rate of the root systems of pine was larger than that of spruce due to the larger size of the root system.

The respiration rate per unit weight of pine roots of the 1- to 3-year-old seedlings decreases significantly with the increasing age. In spruce, the decrease was smaller. The result could have been different if only the short-roots of the same growing season were studied from all seedlings.

During the first growing season the root respiration rate decreased from the middle of the summer towards autumn. An experiment with pine seedlings grown in the mineral soil showed a very rapid increase in respiration rate in the spring. The rate, especially oxygen uptake, is at its greatest in the roots at the time of fastest growth.

  • Lähde, ORCID ID:E-mail:
article id 7142, category Article
Seppo Ervasti. (1964). Suomen sahateollisuuden kausivaihtelu. 2. Tutkimustulokset. Acta Forestalia Fennica vol. 76 no. 2 article id 7142. https://doi.org/10.14214/aff.7142
English title: Seasonal variation in the sawmill industry of Finland II. Investigation results.

Seasonal variation in the sawmill industry of Finland was studied in an investigation based on questionnaires answered by a random sample of sawmills concerning the time period of 1958-1960. The method is described in detail in a separate article in Acta Forestalia Fennica issue 75 no. 1.

The seasonal variations in purchase of roundwood was largest in big sawmills, which purchase the main part of the timber as standing sales and buy most of the wood from the State Forest auctions at the end of September. Also, they can afford to reserve their material earlier than the smaller companies. The saw logs are mainly felled in the winter in Finland because the climatic conditions and availability of labour are best at that time. Small sawmills begin fellings a little earlier than the larger ones.

In long-transport of timber the proportion of floating decreased from 47% in 1958 to 38% in 1960. At the same time, proportion of truck transport increased from 48% to 55%. Small sawmills use almost exclusively land transport. They received almost three-fourths of their logs between January and May, because the sawing is concentrated in the first half of the year. Therefore, floating does not suit for their transport method. The larger the sawmill, the later is the seasonal peak of log deliveries. The output of the big sawmills is distributed more evenly thoughout the year. The smaller the sawmill, the quicker is the turnover of raw material and the smaller the sawlog inventories.

The seasonal variation in output is sharper at small sawmills where sawing is concentrated in the first half of the year. The seasonal peak of the early spring is due to the aim at getting the sawn wood to dry early enough for shipments in the summer. Air drying takes an average of 4 ½ months. Kiln drying is more common at the larger sawmills, and gives them more flexibility. Due to the large seasonal variation in operation, the capacity of the small mills is poorly utilized. Domestic sales of sawn wood levels up the seasonality of the deliveries. Export sales are concentrated at the end and turn of the year. Also, the seasonal peak of expenditure occurs in the winter, but that of income in the summer.

The PDF includes a summary in English.

  • Ervasti, ORCID ID:E-mail:
article id 7141, category Article
Seppo Ervasti. (1963). Suomen sahateollisuuden kausivaihtelu. 1. Aineiston hankinta ja käsittely sekä tulosten luotettavuus. Acta Forestalia Fennica vol. 76 no. 1 article id 7141. https://doi.org/10.14214/aff.7141
English title: Seasonal variation in the sawmill industry of Finland I. Collection and treatment of the material and reliability of the results.

The purpose of this paper is 1) to establish the possible seasonal variation of the different phases of work in the sawmill industry in Finland, 2) to study the internal and external factors influencing the seasonal character of the sawmill industry, 3) to study ha time lags between the work phases of the sawmill industry, 4) to analyse the seasonal nature of the industry’s money transactions, and 5) to give information concerning the factors influencing employment. The investigation is based on questionnaires of a random sample of sawmills concerning the time period of 1958-1960. This paper concentrates on the methods of the study, the results are reported in a separate paper in the Acta Forestalia Fennica issue 75 vol 1.

It was concluded that if seasonal variation in the sawmill industry is to be analysed on the scale it has been in the present work, sampling is the cheapest and most practicable method of collecting the material. If seasonal fluctuation of the industry is to be calculated by size classes, the sample must be allocated into strata by measuring the heterogeneity of the classes with a parameter illustrating seasonal variation. It might be useful to apply these parameters already when the total size of the sample is determined. For the smallest sawmills, for which practically all data have to be collected from primary documents, the most practical method is perhaps to send collectors to the spots. To the larger sawmills the questionnaire can perhaps be sent by mail. A moving index should be obtained for calculation of a seasonal index, but this demands long time series. The collection of the data is described in detail.

The PDF includes a summary in English.

  • Ervasti, ORCID ID:E-mail:
article id 7464, category Article
Erkki K. Kalela. (1956). Ü̈ber Veränderungen in den Wurzelverhältnissen der Kiefernbestände im Laufe der Vegetationsperiode. Acta Forestalia Fennica vol. 65 no. 1 article id 7464. https://doi.org/10.14214/aff.7464
English title: Variations of the root systems of a pine stand during the growing period.

The article presents the results of the studies about the horizontal root systems of pine. The results have been obtained with the method developed by the author.

The size of the root system varies very strongly during the growing period. The amount of roots is at the smallest in the spring, increasing then rapidly and peaking at the end of July. After that the amount of roots decreases again against the winter to the same size than in the spring. The differences are due the changes in the amount of the smallest roots. There seem to be no big differences in the amount of roots between stand of different ages.

After the thinning there is a drop in the amount of roots on the stand level, but after two growing periods then standing trees have taken over the unused land. However after selection felling the less vital trees are not capable of utilizing the vacant resource as effectively.     

The PDF contains a summary in Finnish. 

  • Kalela, ORCID ID:E-mail:
article id 7448, category Article
Viljo Holopainen. (1954). Suomen havusahatavaran viennin kausimaisuus. Acta Forestalia Fennica vol. 61 no. 36 article id 7448. https://doi.org/10.14214/aff.7448
English title: The seasonal fluctuations in the Finnish exports of sawn softwood.

The purpose of the investigation was to examine the seasonal pattern in Finnish export shipments and export sales of sawn softwood in 1927-1953. Statistics concerning shipments have been obtained from the Board of Customs, and material relating to sales has been provided by the Finnish Sawmill Owner’s Association (now Finnish Sawmills Association). On the basis of original monthly statistics, 13-month moving averages were computed. Finally, a seasonal index was calculated.

According to the results, the export shipments have a fairly apparent seasonal pattern with very low figures from January to April, a peak from June to August, and thereafter a gradual decline up to the end of the year. There are also considerable variations from year to year but in general the exports follow this rhythm. In contrast to export shipments the seasonal pattern of export sales is characterised by significant irregularity. Market developments and speculation play a far greater role than the seasonal factors. Indeed, a seasonal character in export sales can scarcely be discerned.

The Acta Forestalia Fennica issue 61 was published in honour of professor Eino Saari’s 60th birthday.

The PDF includes a summary in English.

  • Holopainen, ORCID ID:E-mail:
article id 5598, category Article
Timo Kuuluvainen, Kari Leinonen, Markku Nygren, Antti Penttinen. (1996). Statistical opportunities for comparing stand structural heterogeneity in managed and primeval forests: an example from boreal spruce forest in southern Finland. Silva Fennica vol. 30 no. 2–3 article id 5598. https://doi.org/10.14214/sf.a9243

The horizontal and vertical stand structure of living trees was examined in a managed and in a primeval Norway spruce-dominated forest in Southern Finland. Tree size distributions (DBHs, tree height) were compared using frequency histograms. The vertical distribution of tree heights was illustrated as tree height plots and quantified as the tree height diversity (THD) using the Shannon-Weaver formula. The horizontal spatial pattern of trees was described with stem maps and quantified with Ripley's K-function. The spatial autocorrelation of tree sizes was examined with semivariogram analysis. In the managed forest the DBH and height distributions of trees were bimodal, indicating a two-layered vertical structure with a single dominant tree layer and abundant regeneration in the understory. The primeval forest had a much higher total number of trees which were rather evenly distributed in different diameter and tree height classes. The K-function summaries for trees taller than 15 m indicated that the primeval stand was close to complete random pattern. The managed stand was regular at small distances (up to 4 m). The semivariograms of tree sizes (DBH tree height) showed that the managed forest had a clear spatial dependence in tree sizes up to inter-tree distances of about 12 meters. In contrast, the primeval spruce forest had a variance peak at very short inter-tree distances (< 1 m) and only weak spatial autocorrelation at short inter-tree distances (1–5 m). Excluding the understory trees (h < 15 m) from the analysis drastically changed the spatial structure of the forest as revealed by semivariograms. ln general, the structure of the primeval forest was both horizontally and vertically more variable and heterogeneous compared to the managed forest. The applicability of the used methods in describing fine-scale forest structure i discussed.

  • Kuuluvainen, ORCID ID:E-mail:
  • Leinonen, ORCID ID:E-mail:
  • Nygren, ORCID ID:E-mail:
  • Penttinen, ORCID ID:E-mail:
article id 5561, category Article
Jari Liski. (1995). Variation in soil organic carbon and thickness of soil horizons within a boreal forest stand – effect of trees and implications for sampling. Silva Fennica vol. 29 no. 4 article id 5561. https://doi.org/10.14214/sf.a9212

Spatial variation in the density of soil organic carbon (kg/m2) and the thickness of soil horizons (F/H, E) were investigated in a 6 m x 8 m area in Scots pine (Pinus sylvestris L.) stand in Southern Finland for designing an effective sampling for the C density and studying the effect of trees on the variation. The horizon thickness of the podzolized soil were measured on a total of 126 soil cores (50 cm deep) and the C density of the organic F/H and 0–10 cm, 10–20 cm and 20–40 cm mineral soil layers was analysed.

The C density varied 3–5 fold within the layers and the coefficients of variation ranged from 22 % to 40%. Considering the gain in confidence per sample, 8–10 samples were suggested for estimating the mean C density in the F/H and 0–40 cm layers, although about 30 samples are needed for 10% confidence in the mean. The C densities and horizon thicknesses were spatially dependent within the distances of 1–8 m, the spatial dependence accounting for 43–86% of the total variance. The F/H layer was thicker and contained more C within 1–3 m radius from trees. In the 10–20 cm and 20–40 cm layers (B horizon) the C density also increased towards the trees, but more pronouncedly in the immediate vicinity of the stems. Because the spatial patterning of the E horizon thickness was similar, the increase was attributed to stemflow and precipitation of organic compounds in the podzol B horizon.

  • Liski, ORCID ID:E-mail:
article id 5482, category Article
Heljä-Sisko Helmisaari. (1992). Spatial and age-related variation in nutrient concentrations of Pinus sylvestris needles. Silva Fennica vol. 26 no. 3 article id 5482. https://doi.org/10.14214/sf.a15643

Spatial and age-related variation in nutrient concentrations of Scots pine (Pinus sylvestris L.) needles was studied during 1984–86 in three stands of different stages of development. The dry weight of current needles was significantly (p < 0.05) higher in the tree top than in a composite sample representing the whole crown. However, there were no significant differences in the concentrations of nutrients in needles between upper and lower crown levels. The concentrations of mobile nutrients N, P, K and Mg decreased with increasing needle age whereas the concentrations of poorly mobile nutrients Ca, Mn and Fe increased during needle ageing. The coefficient of variation for nutrient concentrations varied irregularly when only a few trees were sampled but stabilized when tree number was ten or more.
The PDF includes an abstract in Finnish.

  • Helmisaari, ORCID ID:E-mail:
article id 5466, category Article
Hely Häggman. (1991). Application of biotechnology to forest tree breeding. Silva Fennica vol. 25 no. 4 article id 5466. https://doi.org/10.14214/sf.a15624

Forest tree breeding involves manipulation of genetic composition of populations and individuals, and biotechnology focuses on selected individuals. The new techniques cannot replace the conventional breeding techniques but both need effective cooperation of each other. Thus, the distinction between conventional breeding and biotechnology is artificial. The biotechnology methods are new and fast developing and the future with field and progeny testing will show which techniques will be permanently adopted into tree breeding. For instance, the earlier hope of the use of somaclonal variation as a new source of variability and a powerful tool for the breeder seem today quite the opposite. Somaclonal variation constituting a major problem in present-day micropropagation is due to the unpredictable variation. Based on knowledge of today, especially micropropagation via somatic embryos, transgenic trees and the identification of major genes seem to be good candidates to be permanently adopted into tree breeding.

  • Häggman, ORCID ID:E-mail:
article id 5430, category Article
Winai Sirikul, Markku Kanninen. (1990). Shoot growth and its clonal variation in Pinus kesiya. Silva Fennica vol. 24 no. 3 article id 5430. https://doi.org/10.14214/sf.a15584

Shoot elongation of Pinus kesiya Royle ex Gordon was studied using 2-year old grafts in a clonal seed orchard of the Pine Improvement Centre, located at the Huey Bong Experimental Station near Chiangmai, Thailand (19° 17’ N, 99° 15’ E, 900 m a.s.l.).

The seed orchard had a completely randomized block design with 30 blocks and 80 single-tree plots (clones) in each block. Eleven clones in four blocks were selected out of the total of 80 grafts (clones). From each graft, three lateral branches at the height of 1.6 m from the ground level were selected. Thus, total of 109 branches were measured. Shoot length of branches was measured between July 3, 1983 and March 11, 1984 at approximately bi-weekly intervals. Method of classical growth analysis were used in describing the shoot growth.

The annual shoot growth pattern of P. kesiya exhibited two consecutive sigmoid growth curves, i.e. it consisted of two flushes of shoot elongation, both formed by free growth. Thus, the pattern of shoot growth resembled the caribaea pattern. However, the annual shoot was composed of summer and winter shoots. These could be distinguished from each other by the reproductive organs, which always occur on winter shoot. The shoot contributed 61% of the total annual shoot length.

There were significant differences in the pattern of shoot elongation between the studied clones, which may reflect differences in the adaptation to different environmental conditions.

The PDF includes an abstract in Finnish.

  • Sirikul, ORCID ID:E-mail:
  • Kanninen, ORCID ID:E-mail:
article id 5379, category Article
Timo Kuuluvainen, Timo Pukkala. (1989). Effect of Scots pine seed trees on the density of ground vegetation and tree seedlings. Silva Fennica vol. 23 no. 2 article id 5379. https://doi.org/10.14214/sf.a15536

The study uses the methodology of ecological field theory to model the effect of Scots pine (Pinus sylvestris L.) seed trees on the density of tree seedlings and other plants in the field layer. The seed trees had a clear effect on the expected value of the amount and distribution of the ground vegetation. The vicinity of seed trees had an adverse effect on the growth of grasses, herbs and seedlings, while mosses were most abundant near the trees. Models based on the ecological field approach were derived to describe the effect of seed trees on the ground vegetation.

The PDF includes an abstract in Finnish.

  • Kuuluvainen, ORCID ID:E-mail:
  • Pukkala, ORCID ID:E-mail:
article id 5350, category Article
Heikki Hänninen, Paavo Pelkonen. (1988). Frost hardiness and over-wintering of forest trees. Silva Fennica vol. 22 no. 3 article id 5350. https://doi.org/10.14214/sf.a15507

This issue of Silva Fennica consists of eight articles, which are based on a co-nordic conference ”Frost hardiness and over-wintering in forest tree seedlings”, held in Joensuu, Finland, during December 1–3, 1986. The whole annual cycle of the trees is considered. Emphasis is given on methods for the study of frost hardiness, genetic variation in frost hardiness, nitrogen metabolism, bud dormancy release, and joint effect of natural and anthropogenic stress factors in the winter damage of forest trees. Practical implications for tree breeding and nursery management are discussed.

The PDF includes an abstract in Finnish.

  • Hänninen, ORCID ID:E-mail:
  • Pelkonen, ORCID ID:E-mail:
article id 5275, category Article
Pirkko Velling, Gérard Nepveu. (1986). Männyn puuaineen laadun ja tuotoksen vaihtelu suomalaisessa provenienssikoesarjassa. Silva Fennica vol. 20 no. 3 article id 5275. https://doi.org/10.14214/sf.a15454
English title: Variation of wood quality and yield in a Finnish series of provenance trials on Scots pine.

The purpose of the study was to determine the effects of the origin of seeds and the location of cultivation of Scots pine (Pinus sylvestris L.) on certain properties particularly important to the pulp industry. The research material consisted of six parallel trials of the same 12 provenances. Increment cores were taken of a total of 1,267 sample trees, 19 years old. The location of the trial site generally affected the properties to a larger extent than the origin of the seed. The effect of the variation of wood density and fibre yield on the cultivation values of the provenances was only a few percentages on average, however, at most the effect was nearly 10%. Eastern Finnish provenances adapted well to western Finnish conditions.

The PDF includes an abstract in Finnish and French.

  • Velling, ORCID ID:E-mail:
  • Nepveu, ORCID ID:E-mail:
article id 5256, category Article
Outi Muona, Raimo Hiltunen, Erkki Morén, D. V. Shaw. (1986). Analysis of monoterpene variation in natural stands and plustrees of Pinus sylvestris in Finland. Silva Fennica vol. 20 no. 1 article id 5256. https://doi.org/10.14214/sf.a15435

Variation of monoterpene composition of Pinus sylvestris L. was studied in Southern, Central and Northern Finland using data from both natural stands and plus trees. The natural stands were analysed using different techniques and for fewer terpenes than the plus trees.

There were large differences between areas in the proportion of 3-carene in trees from natural stands, as has been discussed by previous authors. The proportion of 3-carene is bimodally distributed and believed to be controlled by a single gene with large effect. For this reason, we stratified our samples into high carene (>10%) and low carene (<10%) groups. Univariate analysis did not reveal any additional differences between natural populations in different zones for components other than 3-carene. In plus trees, several components showed significant differences, but the proportion of 3-carene did not differ between areas. Multivariate discrimination analysis did not distinguish between areas for natural stands. However, for the plus trees discriminant analysis allowed us to discriminate between the zones relatively efficiently. The proportion of correct classification was greater than 64% using the best methods. The central zone was most distinct, and 80% of its trees were correctly classified. Broad generalizations are not possible due to the limitations imposed by our data. Our analysis of phenotypic variation does not support the suggestion that plus trees selected from the north represent a southern type.

The PDF includes an abstract in Finnish.

  • Muona, ORCID ID:E-mail:
  • Hiltunen, ORCID ID:E-mail:
  • Morén, ORCID ID:E-mail:
  • Shaw, ORCID ID:E-mail:
article id 5160, category Article
P. M. A. Tigerstedt. (1982). Metsäpuiden populaatiogenetiikka. Helsingissä 1981 pidetyn symposion tutkimusraportit. Silva Fennica vol. 16 no. 2 article id 5160. https://doi.org/10.14214/sf.a15075
English title: Population genetics of forest trees.

The publication comprises proceedings of a conference held in Helsinki in 1981. Forest tree populations are investigated for population genetic structure, mating systems, mechanisms of genetic adaptation and ecological adaptation. Methods and techniques used in population genetic research of forest trees are presented. Much concern is given to applications by means of forest tree breeding, particularly the seed orchard breeding technique. Generally, the application of population genetics in cultivated forests is discussed.

The PDF includes a preface and the presentations of the conference (25 short papers) in English, and a comprehensive summary of the themes of the conference in Finnish.

  • Tigerstedt, ORCID ID:E-mail:
article id 5062, category Article
I. Etverk. (1980). Geographical variability of the Norway spruce in the Estonian SSR. Silva Fennica vol. 14 no. 1 article id 5062. https://doi.org/10.14214/sf.a15003

The productivity and several morphological features of Estonian Norway spruce (Picea abies L. Karst.) show significant geographical variation. This is no doubt because of differences in the climatic and soil conditions, which in spite of the small area of the country is quite large. In order to check the possible geographical variability of the gene pool, preliminary experiments were carried out in 1969, when seeds from 93 spruce stands originating from 14 forest enterprises were sowed in a nursery. After two years, the seedlings originating from south-eastern Estonia were the tallest. The seedlings from northern origins were smallest. However, it cannot be maintained that spruces from Southern Estonia are of better genotype than genotype from Northern Estonia since the genotypes are evaluated on the basis of ecological conditions under which the experiments are carried out. Another study suggests that an average shift of 7° to the east of the territory for spruces are suitable for cultivation in Estonia.

The PDF includes a summary in Finnish.

  • Etverk, ORCID ID:E-mail:
article id 4868, category Article
Mikko Tormilainen. (1972). Havaintoja Oitin siemenviljelyksen mäntykloonien kukinnasta ja käpysadosta. Silva Fennica vol. 6 no. 2 article id 4868. https://doi.org/10.14214/sf.a14671
English title: Studies of flowering and cone crop in a seed orchard of Scots pine.

Male and female flowering, cone crop, and some vegetative characteristics were studied in grafts 10 to 16 years of age in a clonal seed orchard of Scots pine (Pinus sylvestris L.). Genetic variation was found between clones in flowering as well as in cone production. Clone evaluation resulted in similar classifications of clones in different years. A regression analysis showed that crown size clearly increased but previous height growth slightly decreased flowering and cone production. The percentage of pollinated female strobili did not differ between clones.

The PDF includes a summary in English.

  • Tormilainen, ORCID ID:E-mail:
article id 7643, category Article
Pauline Oker-Blom. (1986). Photosynthetic radiation regime and canopy structure in modeled forest stands. Acta Forestalia Fennica no. 197 article id 7643. https://doi.org/10.14214/aff.7643

The relationship between canopy structure and photosynthetic radiation regime are studied in a theoretical basis. In modelling the canopy structure, a statistical approach is applied and the radiation field inside a stand is described in terms of random variables and their distribution. A comparison is made between horizontally homogenous stands and grouped forest stands in order to assess the influence of grouping of foliage on the irradiance distribution in a forest stand. Results show that grouping considerably reduces the interception of radiation and causes a large spatial variation. In coniferous stands the grouping of needles into shoots and the effect of penumbra are shown to have an important influence on the distribution of radiation on the needle area.

The PDF includes a summary in Finnish.

  • Oker-Blom, ORCID ID:E-mail:
article id 7634, category Article
Heikki Smolander. (1984). Measurement of fluctuating irradiance in field studies of photosynthesis. Acta Forestalia Fennica no. 187 article id 7634. https://doi.org/10.14214/aff.7634

The problems caused by the temporal and spatial microvariation in irradiance during field measurements of photosynthesis are studied. It is concluded on the basis of variation analyses based on irradiance data measured in a Scots pine (Pinus sylvestris L.) stand that the microvariation should be measured by integrating it over the measurement time and space.

However, the curvlinearity of the light response of photosynthesis results in biased estimates when linear integration (mean irradiance) is used. The significance of the bias is examined using a simulation technique on irradiance material. Whether the actual integral of photosynthesis can be approximated with mathematical method is next studied. The method gave satisfactory results only for a low curvature response, but the latter method was applicable also to the high curvature response. However, both methods presuppose that the mean and variance are known. Measurement of the variance is based on integration of the second power.

A new method, where the nonlinearity problem is avoided, is presented to measure fluctuation of the irradiance. The method enables the shoot geometry to be taken into account and it is also applicable to transpiration studies.

The PDF includes a summary in Finnish.

  • Smolander, ORCID ID:E-mail:
article id 7620, category Article
Min-Sup Chung. (1981). Biochemical methods for determining population structure in Pinus sylvestris L. Acta Forestalia Fennica no. 173 article id 7620. https://doi.org/10.14214/aff.7620

Studies on Finnish Scots pine (Pinus sylvestris L.) plus tree clones by monoterpene and isozyme analyses was undertaken to further investigate mating system, population structure and pollination. Six allozyme systems (3 GOT, 1 GDH and 2 LAP) were properly analysed on the basis of segregation. Monoterpenes were analysed from needle material and segregation in high and low 3-carene content was found to depend on two alleles C and c. Thus, six allozyme systems and one monoterpene system were used as markers in this study.

It was shown that the northern clonal group maintains a much genetic variation as the central or southern clonal groups. The conditional probability of self-fertilization in about 20-year old clones estimated by the multilocus model was 14.1%, of which 8% originate from mating between trees that carry the same alleles to one of the maternal parent at some loci and 6% through self-fertilization.

There was no prominent difference in allele frequency of male gametes that pollinated the very early or very late flowering clones. The northern clonal group has higher a lower frequency of alleles GOT B2 and B3 respectively than of the southern clonal groups. The artificial plus tree selection, particularly in northern Finland, appears to favour heterozygous genotypes for the alleles that control 3-carene content n Scots pine.

The PDF includes a summary in Finnish.

  • Chung, ORCID ID:E-mail:
article id 7618, category Article
Songkram Thammincha. (1981). Climatic variation in radial growth of Scots pine and Norway spruce and its importance in growth estimation. Acta Forestalia Fennica no. 171 article id 7618. https://doi.org/10.14214/aff.7618

Variation in the radial growth of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) was studied in 10 localities in Southern Finland. The aim of the study was to utilize the information on variation in the growth indices for growth estimation, and to evaluate the relative accuracy of growth estimation based on the data from increment boring, in comparison to other methods.

The climatic variation in periodic growth (5-year-period) in Southern Finland is about 11% of the normal level. The results suggest that the data from 10 localities can be used in the computation of the index series for Southern Finland and that the data from 10 relascope plots are required in the study of the climatic variation in tree growth in a given locality. The standard error of the estimate in actual growth estimation for past and future periods by the stand function method is about 23%, the errors of the method involving increment boring being 6% and 16% respectively in past and future growth estimation. The respective methods yield about 20% and 13% error in average growth estimation. With aid of the average growth indices for Southern Finland in local growth estimation the accuracy is distinctly improved, the error being equal to 12% only, while the accuracy in other cases is slightly improved.

The PDF includes a summary in Finnish.

  • Thammincha, ORCID ID:E-mail:
article id 7566, category Article
Leo Heikurainen, Kustaa Seppälä. (1973). Ojitusalueiden puuston kasvun jatkumisesta ja alueellisuudesta. Acta Forestalia Fennica no. 132 article id 7566. https://doi.org/10.14214/aff.7566
English title: Regional variation and continuity of stand growth in old forest drainage areas.

The study deals with the development during the 1950s and 1960s of a stand growing on peatlands which had been drained in the 1930s. The following characters were determined by measurements: the volume of the growing stock, the volume increment, the relative increment, the increment percent and the increment curves. Moreover, the possible changes taking place in the difference between tree growth along the ditches and in the middle of the strip between ditches were studied. In addition, the regional variation in increment was studied; this question was studied as the regression between the relative growth and the temperature sum. The results were compared with other Finnish investigations into the regional variation of increment.

The volumes of the growing stock had increased during the course of twelve years by 70–10 m3 /ha depending on the site type and climatic zone concerned. The relative increment had dropped in each case studied. As a matter of fact, this is only to be expected because the volumes had increased and the absolute growth had remained more or less unchanged. The development of the increment percent was compared with mineral soil stands in the case of Southern Finland, both uncut stands and stands treated with cuttings. According to the results obtained, the development of the increment percent was better in the present material than in uncut forests, but in some cases it did not reach the level of tended stands. The revival of the tree crop after draining takes place at different rates in the vicinity of and, on the other hand, at greater distances from the ditches and that this relationship is dependent on the fertility of the site.

The PDF includes a summary in English.

  • Heikurainen, ORCID ID:E-mail:
  • Seppälä, ORCID ID:E-mail:
article id 7547, category Article
Leo Heikurainen. (1971). Pohjavesipinta ja sen mittaaminen ojitetuilla soilla. Acta Forestalia Fennica no. 113 article id 7547. https://doi.org/10.14214/aff.7547
English title: Ground water table in drained peat soils and its measurement.

The present study deals with the ground water table in the soil of drained peatlands and with the technique used for its determination. The terms depth and height of the ground water table are defined in the paper. Because of the fact that the surface of peatlands moves under the influence of a great number of different factors, the depth of the ground water table and the height of the ground water table are not parallel concepts. The present paper concentrates on the depth of the ground water table.

Observations on the depth of the ground water table in the sample plots in 1966-67 and 1968-69 show that the maximum of the late summer usually exceeds that of the early spring, and that the minimum occurring in the period of snow melting is more clearly discernible than that of the fall. Great differences occur in the depths of the ground water table in different sample plots. These differences are due to the specific properties of the peat of different peat layers, which are expressed in terms of the ground water coefficient. The duration of the depth of the ground water table proved to be a useful way to express the long-term changes.

Four kinds of short-term fluctuations in the ground water table were observed: a) the ground water table falls during the night hours, although the rate of falling is slower than in daytime, b) the ground water table rests at the same depth during the night, whereas during the day it clearly falls, c) the descent of the ground water table is similar throughout the whole 24-hour period, d) the ground water table rises during the night hours and falls in daytime. Occurrence of these types are discussed. Typical short-term fluctuation is the fall due to evaporation in the daytime.

The third part of the paper discusses the techniques used to measure the changes in ground water table.

The PDF includes a summary in English.

  • Heikurainen, ORCID ID:E-mail:
article id 7547, category Article
Leo Heikurainen. (1971). Pohjavesipinta ja sen mittaaminen ojitetuilla soilla. Acta Forestalia Fennica no. 113 article id 7547. https://doi.org/10.14214/aff.7547
English title: Ground water table in drained peat soils and its measurement.

The present study deals with the ground water table in the soil of drained peatlands and with the technique used for its determination. The terms depth and height of the ground water table are defined in the paper. Because of the fact that the surface of peatlands moves under the influence of a great number of different factors, the depth of the ground water table and the height of the ground water table are not parallel concepts. The present paper concentrates on the depth of the ground water table.

Observations on the depth of the ground water table in the sample plots in 1966-67 and 1968-69 show that the maximum of the late summer usually exceeds that of the early spring, and that the minimum occurring in the period of snow melting is more clearly discernible than that of the fall. Great differences occur in the depths of the ground water table in different sample plots. These differences are due to the specific properties of the peat of different peat layers, which are expressed in terms of the ground water coefficient. The duration of the depth of the ground water table proved to be a useful way to express the long-term changes.

Four kinds of short-term fluctuations in the ground water table were observed: a) the ground water table falls during the night hours, although the rate of falling is slower than in daytime, b) the ground water table rests at the same depth during the night, whereas during the day it clearly falls, c) the descent of the ground water table is similar throughout the whole 24-hour period, d) the ground water table rises during the night hours and falls in daytime. Occurrence of these types are discussed. Typical short-term fluctuation is the fall due to evaporation in the daytime.

The third part of the paper discusses the techniques used to measure the changes in ground water table.

The PDF includes a summary in English.

  • Heikurainen, ORCID ID:E-mail:

Register
Click this link to register for Silva Fennica submission and tracking system.
Log in
If you are a registered user, log in to save your selected articles for later access.
Contents alert
Sign up to receive alerts of new content
Your selected articles

Committee on Publication Ethics A Trusted Community-Governed Archive