Nursery growth and dry weight of plus tree progenies of Pinus contorta

Height development, stem diameter and dry weight of plus tree progenies of lodgepole pine (Pinus contorta ssp. latifolia) from controlled cross pollination, open pollination and selfing were evaluated in a nursery trial. Early growth was slow in year 1 but more rapid in year 2, and it showed higher correlation with total increment than late growth. Nursery growth was uncorrelated with 10‐year‐height in field. The controlled crosses started growth faster and became higher than the two other types of materials. The family variance within all types differed also significantly. Mother clone had larger influence on 2nd‐year‐growth than father clone. Height and diameter growth were slightly influenced by latitudinal but not altitudinal origin. Prolepsis was independent on both. Specific combining ability (SCA) decreased while general combining ability (GCA) increased by age. For dry weight, SCA was more important than GCA.     

马尾松年轮宽度和木材基本密度的种源变异及早期选择

针对浙江省淳安县姥山林场的24年生49个产地马尾松种源试验林,采集植株胸高处木芯,分析种源年轮宽度和木材基本密度的年龄效应。结果表明:除近髓部1～5轮年轮段的木材基本密度外,其他年龄段的年轮宽度和木材基本密度皆存在显著的种源差异,进一步说明通过种源选择可实现木材生产力和木材基本密度的遗传改良。不同年轮段木材基本密度的种源变异相对稳定,而年轮宽度的种源变异则易受环境的影响,幼龄材年轮宽度的种源变异较小,仅为成熟材的63.29%。来自不同种源区的种源年轮宽度的径向变异规律相似,皆表现出先增后减的变化趋势,在6～10轮达到最大值;年轮木材基本密度径向变化规律则与年轮宽度不同,表现为随年龄增长先增加后逐渐稳定的S型变化趋势,并据此筛选出广西横县、恭城、忻城,广东乳源和福建南靖5个木材基本密度径向均匀性高的纸浆材优良种源。不同年轮段年轮宽度和木材基本密度的相关分析显示,约在8年生选择径向生长快的种源会明显地降低其木材基本密度。基于性状早晚相关分析,认为可在7年生时先淘汰生长较差的种源,在12年生再开展种源生长和木材基本密度的联合选择。     

红松木材密度与气候变化关系的实证分析

运用协整分析对我国东北地区人工林红松木材密度与气候变化的关系进行了研究。结果表明,红松木材密度与气候因素之间存在长期均衡的协整关系和显著的短期动态调整机制。在1973～1997年,2、3月平均日照时间的延长有利于提高早材密度,而7月份的日照时间延长却不利于提高早材密度;2月气温升高,不利于提高整个生长轮密度平均值;误差修正模型和格兰杰检验证实,2月气温短期内对生长轮密度的影响存在2～3年的滞后期。人工林红松的优质培育需要充分考虑气候变化的影响。     

Effect of growth conditions on wood density of Spanish Pinus nigra

The natural forests of Laricio Pine (Pinus nigra Subsp. salzmannii) cover in Spain an area of 353,000 ha, producing annually 310,000 m³ of roundwood. This species is considered as the fourth, most important Spanish conifer, being its timber frequently used in construction. The natural area of distribution of Laricio pine in Spain is officially divided into ten different regions of provenance, being only four of them considered as productive. The present study on the influence of growth conditions on extracted wood basic density (EBD) is carried out on 89 P. nigra trees, sampled from the two most productive Spanish regions of provenance (R.7 and R.8) in seven different sites. Cross-sectional disks were cut at 3 m (in 89 trees) and every 3 m height (in 18 trees) from the butt up to 15 m. For assessing the pattern of radial variation of the properties, 20×20×20 mm³ wood samples were taken radially from every cross-sectional disk. In every 20×20×20 mm³ wood sample, age and distance to the pith of the central annual ring was recorded, together with the average growth rate. Extractive content and EBD were measured in every sample. The results lead to the conclusion that there is not a significant relationship between EBD and provenance or growth rate. On the contrary, a significant relationship has been found between EBD and site quality or cambial age. The results also demonstrate that in a tree EBD tends to diminish from the base to the top and from the pith outwards. The main result of the present study is related with the observation that for the same cambial age, annual ring width has no significant influence on EBD, confirming that its utility as a predictor of the quality of timber is highly questionable, at least if the ring curvature is not considered.     

Changes in tree ring width and density ofPinus thunbergii growing in the vicinity of industrial complex in Korea

There has been a decline in tree growth since the operation of factories atPinus thunbergii forests around a petrochemical industrial complex in Korea. This study was carried out to investigate the effects of air pollution on tree ring width and ring density ofPinus thunbergii. Soft X-ray densitometrical method was used. Decline of ring width was the highest during 3 years immediately after the operation of factories. The percentage of decrease was almost bigger immediately after operation as compared with before. Maximum density (MAXD), and the difference (DD) between maximum density and minimum density (MIND) generally decreased since operation of factories, while minimum density increased in the beginning of operation of factories. There was a significant correlation between ring width and high temperature, and precipitation in the beginning of growing season, respectively. There was also a negative correlation between annual mean concentration of SO₂ and ring width at 5% level (r=−0.627^*). It is suggested that the decline of ring width after operation of factories was due to compound factors of air pollution and climate. The effect of other factors should be still more studied. A part of this paper was presented at the International Workshop on Asian and Pacific Dendrochronology on March 4–9, 1995 in Tsukuba (Forestry and Forest Products Research Institute), Japan.     

Growth rate and shoot: Root allometry in Pseudotsuga menziesii (Mirb.) Franco and Pinus contorta Dougl. Seedlings raised under two photoperiodic regimes

Six provenances of both Pseudotsuga menziesii (Mirb.) Franco and Pinus contorta Dougl. from a range of locations in the interior of British Columbia between latitudes 49° and 58° were grown for 80 days in controlled environment chambers programmed to provide daylengths comparable with those at either latitude 48°, or latitude 58°, during the period from mid‐June to early September. Neither shoot : root ratio nor whole plant dry weight of P. menziesii were affected by photoperiod. However, P. contorta seedlings, which unlike P. menziesii set bud during the experiment, had a greater dry weight and a higher shoot:root ratio (p<0.05) under longer daylengths. The results appear relevant to the interpretation of effects of cross‐latitudinal provenance transfer on plantation productivity.     

章古台地区樟子松年轮宽度和管胞长度的径向变异

对章古台地区不同密度樟子人工林松年轮宽度和管胞长度进行测定,结果表明：章古台地区胸径年轮数30a的樟子松林,已出现生长衰退现象,生长衰退期开始林龄与林分密度有关,降低林分密度可延缓衰退期出现林龄。樟子松管胞长度与距离髓心的年轮数之间存在Y=alnx＋b（Y：管胞长度;X：距离髓心的年轮数．b：第1年轮的管胞长度）关系。不同密度樟子松年轮宽度不同,但管胞长度与未成熟材范围无显著变化,未成熟材范围距离髓心的年轮数均为21～23a。     

红松人工林优树个体结实量与生长因子关系的研究

为探讨红松生长指标对结实量的影响,调查了草河口地区30～80年生5个林龄红松人工林优树个体结实量和胸径等生长指标,利用灰色关联度方法分析结实和生长因子之间的关系。结果表明,与个体结实量关联度较大的3个生长因子是树高、胸径和侧枝长。因此,除了个体结实量外,树高、胸径和侧枝长可作为红松结实型优树选择的重要依据。     

Pathogenicity of canadian isolates of the Bursaphelenchus xylophilus (pinewood nematode) to provenances of Pinus sylvestris and Pinus contorta as grown in Finland: A greenhouse study

Seedlings of Scots pine (Pinus sylvestris L.) and lodgepole pine (P. contorta Dougl.) provenances, as grown in Finland, were inoculated with “m”; and “r”; “forms”; of the pinewood nematode (Bursaphelenchus xylophilus) from Canada, an m form isolate from France and an r form isolate from Missouri, USA. Scots pine was highly susceptible to an Alberta r form and a British Columbia m form isolate and moderately susceptible to two Quebec m form isolates. Lodgepole pine was higly susceptible to the two r form (Alberta and Missouri) isolates and moderately susceptible to the British Columbia m form and the two Quebec m form isolates. Mortality of both pines after inoculation with the French isolate was inconsistent. Mortality of both pines occurred more rapidly following inoculation with r form than with m form nematodes. Large numbers of nematodes were generally found in the tissues of both pines. Our results with seedlings need to be corroborated by inoculating larger field‐grown trees.     

感染松材线虫病的思茅松林择伐木外观判定初探

通过观察思茅松在12月至翌年1月感染松材线虫病的外部特征,得出思茅松感病后的主要外部特征和区别于其他松树的感病特点,并提出择伐感病思茅松时在外观特征上的判定标准和处理建议。     

25年生马尾松优树子代生产力评价及家系选择

对25年生马尾松优树子代测定林调查分析,结果表明马尾松子代树高、胸径、材积在家系间存在显著的遗传变异,其家系遗传力分别为0.428、0.565和0.610。利用以树高、胸径、材积构建的指数选择方程从参试家系中选择出20个速生优良家系,平均材积遗传增益为26.0%。从入选的优良家系中选择出100株优良单株,平均材积比群体均值大122.21%。     

Index selection for growth and construction wood properties in Pinus elliottii open-pollinated families in southern China

The initial introduction of Pinus elliottii (PEE) to China occurred in the 1930s, and the planting of this conifer species has now attained close to 3 million ha in the subtropical zone of southern China. A large-scale genetic improvement program for PEE was implemented in southern China to produce fast-growing trees with high wood quality to address the severe shortage of timber production over the last two decades. In this paper, selection for stem volume, basic wood density (DEN) and modulus of elasticity (MOE) was based on the Smith–Hazel index, and a total of approximately 2 000 individual trees from 158 PEE open-pollinated families were selected at 22 years of age. The DEN and MOE for each tree were determined by non-destructive evaluation techniques using the Pilodyn and Hitman Director ST300® acoustic velocity device. The heritabilities and genetic and phenotypic correlations for the traits that were measured were estimated using the residual maximum likelihood approach in the flexible mixed modelling program ASReml-R. The results showed that the heritability estimates for the wood properties were between 0.292 and 0.309, and the heritabilities of the growth traits ranged from 0.129 to 0.216. The genetic correlation between the DEN_P and acoustic velocity (V?) with MOE_P was 0.45 and 0.95, respectively. An indirect selection based on V was observed to be highly effective for determination of MOE. It indicated that V can be integrated into tree improvement programs as a useful index of MOE by ranking candidate families or individuals within the selection population. The genetic correlations between the growth traits and wood properties were not significant. By contrast, the phenotypic correlations between them were significantly positive, but the correlation coefficients were very low. The appropriate selection index (I₄), which placed 10 times as much weight on DEN and MOE as the equal emphsis method, was determined as the appropriate selection index.     

Simulation of the growth ring density of Larix olgensis plantation wood with the ARMA model

Because growth ring data have temporal features, time series analysis can be used to simulate and reveal changes in the life of a tree and contribute to plantation management. In this study, the autoregressive(AR) and moving average modeling method was used to simulate the time series for growth ring density in a larch plantation with different initial planting densities. We adopted the Box–Jenkins method for the modeling, which was initially based on an intuitive analysis of sequence graphs followed by the augmented Dickey–Fuller stationarity test. The order p and q of the ARMA(p, q) model was determined based on the autocorrelation and partial correlation coefficient figure truncated on the respective order.Through the residual judgment, the model AR(2) was only fitted to the larch growth ring density series for the plantation with the 1.5 9 2.0 m^2 initial planting density.Because the residuals series for the other three series was not shown as a white noise sequence, the modeling was rerun. Larch wood from the initial planting density of2.0 9 2.0 m^2 was modeled by ARMA(2, 1), and ARMA((1, 5), 3) fitted to the 2.5 9 2.5 m^2 initial planting density,and the 3.0 9 3.0 m^2 was modeled by AR(1, 2, 5).Although the ARMA modeling can simulate the change in growth ring density, data for the different growth ring time series were described by different models. Thus, time series modeling can be suitable for growth ring data analysis, revealing the time domain and frequency domain of growth ring data.     

Basic density,longitudinal shrinkage and tracheid length of juvenile wood of Picea abies (L.) Karst

Variation in the growth ring width, basic density, longitudinal shrinkage and tracheid length was investigated in the juvenile wood of Norway spruce samples taken from different heights in the stem. Annual height increments were cut from the ten youngest shoots from trees of three different heights. By this method the properties of an individual growth ring could be analysed without taking samples from each ring. Sixteen tree tops of an average stem height of 8, 15 and 25 m were analysed. Basic density was low in the first shoot, highest in the second or third one and decreased gradually thereafter. Longitudinal shrinkage was highest close to the pith and decreased to about 0.2% in the outer rings. Tracheids were only ca. 1 mm long close to the pith and their length increased sharply towards the tenth shoot. The properties of juvenile wood varied with the height in the stem. Longitudinal shrinkage around the pith seemed to increase with increasing height and basic density was highest at 25 m stem height. The applicability of the method for the calculation of basic density and tracheid length in individual growth rings close to the pith is discussed.     

次生林下红松幼树的最佳生长条件

全文对杨桦次生林下红松幼树的最佳生长条件进行了研究。结果表明，林下无灌木或少灌木，距离立木1．5m以外，林冠郁闭度0.5-0.6为红松幼树更新的最佳条件。同时，提出了通过胸径与林分密度的关系对林分郁闭度进行控制的直接方法。     

Genetic parameters of growth and wood quality traits in Picea abies

Genetic parameters were estimated for wood and growth traits in two 19-yr-old clonal trials and a 40-yr-old full-sib progeny trial of Norway spruce [Picea abies (L.) Karst.]. In the clonal trials high (>0.4) broad-sense heritabilities were found for wood density traits, lignin content, number of internal cracks, growth traits, spiral grain and number of resin canals. Moderate (0.2–0.4) heritabilities were found for tracheid lumen diameter and cell wall thickness, microfibril angle and tracheid length, while low heritabilities (<0.2) were found for pulp yield, fibre strength, wood stiffness and wood colour. Lignin content and pulp yield showed low genetic variation, whereas the genotypic coefficient of variation for most other traits ranged between 5 and 15%. Most traits showed low levels of genotype by environment interaction. Among the wood properties, latewood proportion, earlywood density and ring density showed significant, adverse correlations with volume in both clonal trials.     

Development of a method for sorting picea abies pulp wood with respect to basic density

The basic density of pulp wood can be used to convert green volume to dry weight, and as an indicator of the fibre quality. Because the methods for measuring basic density are cumbersome, a practical, on‐line method for sorting Norway spruce pulp wood with respect to basic density was developed. The relationship between mean annual ring width and basic density was used to sort the pulp wood. Brief visual inspection could separate piles of logs with different mean annual ring widths from each other with an acceptable precision. The resulting classes had significantly different mean basic densities (380, 400 and 434 kg m^?3). Means of other properties, such as juvenile wood content, heartwood content, and dry matter content, also differed among classes.     

The variation of the basic density within the juvenile wood of Sitka spruce (Picea sitchensis)

The variation in the basic‐density level of 45 stems of Sitka spruce from two Danish sites has been examined. It is shown that the basic‐density level, i.e. the basic density as a function of ring width, within the juvenile wood decreases with (1) increasing distance from the pith and (2) increasing height in the stem (same ring number from pith provided). Furthermore, the basic‐density level seems to decrease with increasing stand quality, which may affect the pattern of variation in basic‐density level if the stand quality class varies with age. The basic density of the juvenile wood is markedly higher in Sitka spruce than in Norway spruce, whereby the risk of stem cracks probably is reduced.     

Timber quality and volume increment of advance growth and planted Pinus sylvestris

Timber quality and increment of Scots pines were analysed in two adjacent stands in northern Sweden. One stand originated from advance growth, and one from planted seedlings. Height increment of advance growth that was higher than 1.3 m when released was slow compared with advance growth lower than 1.3 m and planted trees. Timber quality of advance growth, > 1.3 m at release, was poor due to high incidence of stem damage, most likely inflicted during the logging operation. Potential timber quality of planted Scots pines was better among dominated than dominating trees. Volume production was more than twice as high in the plantation as in the stand originating from advance growth. Slash burning after clear felling had a positive effect on production in the plantation.