References Assmann E. (1968): Nauka o produkcyjności lasu [Forest yield science]. PWRiL, Warszawa. [in Polish]. Graczyk M., Kaźmierczak K., Zawieja B. (2010): The longitudinal analysis applied to the analysis of heightincrement of pine stands. Biometrical Letters 47(2): 199-128. Kaźmierczak K., Zawieja B. (2008): An attempt to assess the correlation between lengthwise growth of the main shoot in 24-year old Scots pines ( Pinus sylvestris L) on the growth of lateral branches. Biometrical Letters 45(1): 81-92. Krzyśko M. (2000): Wielowymiarowa analiza
References Assmann E. (1968): Nauka o produkcyjności lasu [Forest productivity science]. PWRiL, Warszawa. Beker C. (1998): Przyrost wysokości w drzewostanach sosnowych starszych klas wieku [Heightincrement in pine stands of older age classes]. Sylwan 8: 43-54. Bruchwald A. (1973): Ocena przydatności dla praktyki gospodarczej sposobów określania miąższości drzewostanu [Evaluation of usefulness for economic practice of methods of determination of stand volume]. ZN SGGW, Rozprawy Naukowe 25. Cedro A. (2001): Dependence of radial growth of Pinus Sylvestris L. from
Forest Research 35:1657-1668. Lindholm, M., Ogurtsov, M., Aalto, T., Jalkanen, R., Salminen, H., 2009: A summer temperature proxy from heightincrement of Scots pine since 1561 at the northern timberline in Fennoscandia. Holocene 19:1131-1138. Lindholm, M., Jalkanen, R., Salminen, H., Aalto, T., Ogurtsov, M., 2011: The height-increment record of summer temperature extended over the last millennium in fennoscandia. Holocene 21:319-326. Lukac, M., Godbold 2011: Soil ecology in northern forests: a belowground view of a changing world. Cambridge University Press, Cambridge
missing observations. Forest Ecology and Management, 260, 1965-1974. Gerelbaatar S., Baatarbileg N. 2011. Growth of Scotch Pine (Pinus sylvestris L.) Plantation in Northern Mongolia. Journal of Agricultural Science and Technology, B1, 1205-1210. Kaźmierczak K. 2005. Przyrost wysokości i dokładność różnych metod jego określania na przykładzie wybranych drzewostanów sosnowych. [The heightincrement and accuracy of different methods of its calculation in selected Scots pine stands]. Roczniki AR Poznań, Rozprawy Naukowe, 365 [in Polish]. Lappi J. 1997. A longitudinal
Norway spruce is commonly regenerated by planting and disc trenching is by far the most widely used soil preparation method in Latvia; however, in specific site conditions other methods might be beneficial. Therefore aim of our study was to assess influence of spot mounding on early growth and tending of Norway spruce in hemiboreal forests. Spot mounding was compared with disc trenching or no soil preparation in central part of Latvia (57° N 24° E) in five different forest types, where two-year-old containerized Norway spruce seedlings were planted. Influence of soil preparation method on tending was assessed in the same region in two different sites in a single forest type on drained fertile mineral soil. Spot mounding had positive effect on the height increment of the dominant trees at the 6th to 8th growing season. Mean height of Norway spruce at the end of 8th growing season on mounds significantly exceeded that on unprepared soil: 179 ± 6.5 and 152 ± 6.2 cm, respectively. Similarly mean height on mounds was significantly larger than on furrows: 209 ± 3.9 and 154 ± 4.0 cm, respectively. Projective vegetation cover before the tending was significantly higher in spot-mounded, but after - in disc trenched sites. Networking time for brashsaw operators in spot-mounded (478 min/ha-1) and disc trenched (462 min/ha-1) sites was similar (p > 0.05). Overall, spot mounding ensured more suitable microenvironment resulting in higher productivity of planted trees and had no negative effect on quality or efficiency of tending, therefore its wider use is recommended.
This paper aims to quantify relationships between the biometric parameters of young, 15-year old spruce stands at the Experimental Site Vrchslatina. In 2011, 40 spruce trees were selected to cover four classes of bio-sociological status (dominant, co-dominant, sub-dominant, and suppressed - 10 individuals each). The trees were measured for their height increments (by recording the distances between the successive whorls) and the increments of lateral branches at all whorls. The sample trees were then cut down and discs were taken from the stem base. In the laboratory, the discs were measured for the annual ring widths using WinDendro software. We focused on detailed analyses of the relationship between the bio-sociological status of the trees on the radial and height increments. Minor differences were found in the increments in the newest lateral whorls. The ratio between height increments and lateral branch increments was found to be higher in dominant trees (height increments is two times higher than the increments on the lateral branches). Conversely, the smallest ratio was found in suppressed trees (the ratio was around 1). The ratio between tree height and diameter at the stem base, as well as the ratio between height and radial increments, was the smallest for dominant and the highest for suppressed trees. Hence, relationships between height and diameter increments (both annual and cumulative) proved to reflect competition intensity among trees.
Growth response of young Scots pines to needle loss assessed from productive foliage
The amount of productive foliage was assessed with the help of the relative significance of each annual needle set in their contribution to the growth of young Scots pines (Pinus sylvestris). The number of needles in the subsequent needle sets was studied retrospectively in twelve-year-old stand, and the worst needle loss years were detected. The growth rate of trees was compared with the number of needles in the annual needle sets and with the loss of needles from the assessed productive foliage. Needles in the 4th and older needle sets remaining in the trees were interpreted as useless or less important if their amount did not correlate with the growth. The second and third needle sets supported both radial and height growth. Most variation in the needle loss during 1999-2002, caused mainly by summer drought and by fungal needle cast due to Lophodermium seditiosum, occurred in the third annual needle set. Decrease in both radial and height increments in relation to the needle loss were apparent in the total material for 1997-2004, but needle loss reduced the annual growth significantly only in two-three years inside that period.
The study presents the results of an analysis of the pine tree growth increments (height increment, dbh increment, basal area increment and volume increment) for a 5-year period. The study involved Scots pine trees of Kraft’s class 1, 2 and 3 (dominant stand) in stands of different age classes (II, III, V) growing in fresh mixed coniferous (BMśw) and fresh coniferous (Bśw) forest habitats. The multivariate analysis of variance was performed to assess the statistical significance of age and dominance of trees within a stand on their increment. The dominance position was classified for each tree using Kraft’s criteria. The following characteristic were also measured: dbh of the trunk in two directions (N-S and W-E), and crown projection area on the basis of the characteristic tree crown points, projected using of a crown projector, characteristic points in tree crowns (7 to 14 on average). The actual height was determined after trees were felled. The following measurements of the single tree growing space were selected and determined: crown projection area - pk (m2), crown diameter - dk (m), Seebach’s growth space number - dk / d1.3, crown projection area to basal area ratio d 2 k / d 2 1.3, crown deflection coefficient dk / h, single tree space ppd = pk·h (m3). We assessed the strength of the relationships between tree growth parameters and tree growth space, crown length, relative crown length and slenderness. Both the age and dominance position of trees within the stand affected the growth increments. The strongest correlation among measured traits was between the 5-year volume increment and decreasing slenderness.
Relationships between the volume growth of mixed stands and their species composition were analyzed in order to examine the so-called “mixture effect” on stand productivity. The influence of co-species was studied using multiple linear regression analysis. Stand level basal area and height growth models were constructed in order to find out which stand characteristics can be used to describe mixture-effects. The study material originates from the Estonian network of permanent forest growth plots, only stands consisting of mainly (≥ 50% of volume) Scots Pine with Norway spruce and/or Birch spp. as co-species were used. Sample size was 139 5-year measurement periods on 88 plots; stand ages range from 14 to 167 years. The study results indicate that an increasing proportion of birch in the stand causes a negative effect on both basal area and height growth. Spruce seems to be a weaker competitor than other pines as its trend in the model is positive. Also, height growth is more rapid when the mean diameter of spruce is smaller than that of pine. Species composition coefficients for co-species (calculated by standing volume) proved to be the most significant variables that describe stand composition in the models
models for major target variables, including diameter increment, heightincrement, crown ratio and mortality. Because management decisions often require precise and accurate predictions, existing individual tree growth models have been evaluated in many studies ( Sterba et al., 2001 ; Pretzsch, 2002 ; Kindermann and Hasenauer, 2007 ; Schmidt and Hansen, 2007 ). Model evaluation provides end-users with information on the accuracy of the model. It gives insight into errors and deficiencies, and helps in improving the models. Model evaluation examines whether the model