彭场林场高产脂、高产材湿地松优树选择研究

以荆门市彭场林场66.7hm230多年生湿地松母树林为研究对象,经过连续几年的观测和调查,采用普选法,以材积和产脂量双指标控制,选择出了14株高产脂、高产材优树,其材积比一般湿地松大20%,产脂量高200%,为湿地松优良品系改良与推广打下了基础。     

Somatic Embryogenesis and Plantlet Regeneration in Callus Cultures Derived from Mature Zygotic Embryos of Slash Pine

1TheworkwassupportedbyChineseNationalHighTechnologyDevelopmentProgram"863project"IntroductionSomaticembryogenesishasagreatpotentiaIforrapidProPaationofsuPCriorconifcrspccics.ThefirstreportonsomaticembryogenesisandplantlctrcgencrationinconifersPeCieswasach…     

Bud development and dormancy in slash and loblolly pine. I. Speed of budbreak and second year height as related to lifting date

Slash and loblolly pine 1-0 seedlings were lifted from the nurserybed in late November, mid-December, late December, and mid-February. The buds of the seedlings were classified as set or growing two weeks prior to lifting and were re-examined upon lifting. For both species, buds that had set remained set whereas those that were classified as growing showed an decreasing trend of setting from November through December. A subset of seedlings was potted and maintained in a greenhouse to determine rate of budbreak; the remainder were field planted. In the greenhouse, loblolly pine broke bud fastest and slowest when lifted in mid-February and mid-December, respectively. The rate of slash pine budbreak increased over successive lifting dates. In the field, loblolly pine lifted in mid-December exhibited the highest percentage of growing seedlings; these seedlings were also tallest after one year in the field. Field-planted slash pine had the highest percentage of growing seedlings when lifted in late November. However, seedlings lifted in mid-December were tallest after one year.     

马尾松纸浆林造林密度对木材性质的影响

本文研究了龙里林场5种造林密度，15年生马尾松纸浆林木材基干密度和管胞形态。结果表明：造林密度对木材基本密度影响不大，但具明显的趋势，即一定造林密度条件下，木材基本密度随造林密度增加而增加，造林密度对管胞形态的影响，表现出因年龄而异，不同造林密度马尾松管胞形态总平均值变化不大，但管胞长度随树龄的增大而增加的趋势，受到造林密度影响，较低的造林密度各生长轮管胞形态差异不显著。管胞长度频率分布具一定的规律，中等长度（2501－3500um)管胞长度频率分布最大，占总频率的45％－74．19％，随着造林密度加大，中等长度的管胞增加，较短管胞长度（≤2500um)减少。     

Wood quality in alleycropped eastern black walnut

Thinnings from a 15-year-old eastern black walnut (Juglans nigra L.) agroforestry plantation in SW Missouri (USA) were evaluated to determine the influence of cropping practices on wood quality. Growth rate was found to be strongly affected by weed control and cropping practices while specific gravity and fiber length (measured in selected stems) were found to be weakly affected. of Missouri's Agricutural Experiment Station Journal Series.Research supported by McIntire-Stennis funds. This is Paper No. 11,859 in the University of Missouri's Agricutural Experiment Station Journal Series.     

Two-year development of southern pine seedlings and associated vegetation following spray-and-burn site preparation with imazapyr alone or in mixture with other herbicides

Eight herbicide combinations containing imazapyr alone or in mixture with glyphosate, triclopyr, or picloram+2,4-D were applied July–August 1991 at each of three upland sites in the southeastern U.S., with or without a subsequent broadcast burn in September. Seedlings of loblolly (Pinus taeda L.) or slash (P. elliottii Engelm. var. elliottii) pine were planted that winter. Second-year (August 1993) vegetation responses indicate that broadcast burning, in combination with herbicides, was associated with increased abundances of grasses, forbs, and shrubs and decreased abundances of vines and hardwood trees. In the presence of burning, imazapyr-in-mixture treatments were associated with a high abundance of grass (53% cover) and a mean size of pines less than that of seedlings growing in imazapyr-alone treatments. In the absence of burning, imazapyr-alone treatments were associated with a high abundance of blackberry (21% cover), an average height of hardwoods (131 cm) exceeding that of pines (71 cm), and a mean size of pines less than that of trees growing in imazapyr-in-mixture treatments. Hardwood height in the absence of burning was less when imazapyr was combined with glyphosate (75 cm) than with triclopyr (102 cm). Regardless of the presence or absence of burning, size of pines and abundance of shrubs and hardwoods did not differ between imazapyr rates of 0.56 and 0.84 kg acid equivalent/ha or among herbicides applied in mixture with imazapyr.     

Bud development and dormancy in slash and loblolly pine. II. Effects of ethephon applications

Ethephon application on four dates did not induce budset in slash and loblolly pine seedlings. Ethephon promoted slash pine budbreak by 11 days when applied in mid-November and delayed loblolly pine budbreak by 8 days when applied in late November. Mid-November and early February applications of ethephon promoted height growth of both species.     

33个生态林阔叶树种在惠州市丘陵山地生长分析

比较研究了广东省惠州市惠阳区秋长镇7年生人工生态林33个阔叶树种的生长。结果表明：长叶竹柏(Nageia fleuryi)、乌桕(Triadica cochinchinensis)和白兰(Michelia alba)等8个树种造林早期存活率较低,在荒山造林中生长表现欠佳;其余树种在荒山造林中效果良好。聚类分析结果将26个树种划分为3类：第1类为猴耳环(Archidendron clypearia)、米锥(Castanopsis carlesii)、红锥(C. hystrix)等9个生长快速的树种;第2类为盆架子(Alstonia rostrata)、樟树(Cinnamomum camphora)、肖蒲桃(Syzygium acuminatissimum)等12个生长速度中等的树种;第3类为桂木(Artocarpus lingnanensis)、铁冬青(Ilex rotunda)、麻楝(Chukrasia tabularis)等5个生长缓慢的树种。     

Variations in wood anatomical properties and specific gravity of half sib progenies of Populus deltoides

We studied radial and inter-progeny variations in the dimensions of the wood elements and specific gravity of 21 half sib progenies of Populus deltoides Bartr. ex Marsh. The female parents of half sibprogenies were G48 and S7C13 clones. Variance ratio (F) test indicated that inter-progeny variations in the dimensions of wood elements andspecific gravity were significant for all wood traits while variations were significant for radial location for specific gravity only. Hierarchical cluster analysis was done by Squared Euclidean Distance for all of 21 progenies considering six wood traits. 21 progenies were grouped into 4 clusters. Cluster 1 was the largest cluster with 11 progenies, whereas cluster 3 had only one progeny. Selected progenies in clusters 3 (progeny 155,male) and 4 (progeny 108, 196, both female) were highly divergent from the other progenies so they were used in combinations as parents of hybrids to develop new clones with desired characters. Progeny 155 showed higher growth, fiber dimensions, and specific gravity, thus,should be used for the development of new clones.     

Loblolly and slash pine height and diameter are related to soil drainage in winter on poorly drained silt loams

Soil drainage characteristics in winter and the heights and diameters of 10-year-old loblolly and slash pines (Pinus taeda L. and P. elliottii Engelm. var. elliottii) were measured on three poorly-drained silt loam sites that had been bedded, furrowed, or disked before planting. Quadratic response functions were used to determine the relationship between depth to water table or volume of drained soil in winter and mean tree height or diameter. These quadratic response functions (species × height or diameter: drainage characteristics) showed that diameter and height were significantly related to soil drainage in winter on these silt loams soils. Slash pines grew better than loblolly pines under more poorly drained conditions while loblolly pines grew better under the better drained conditions. On unbedded silt loams, the soil drainage in winter needed to maximize tree height was 42 cm for loblolly and 49 cm for slash pine. Pines planted on beds did not generally grow better than those on flat-disked plots because where bedding would be most benefical the practice did not form enough additional drainage to significantly influence pine development.     

Performance and variability patterns in wood properties and growth traits in the parents, F1 and F2 generation hybrid clones of Populus deltoides

The performance and variability patterns in the wood element’s dimensions, specific gravity and growth parameters namely ramet height and GBH were evaluated in 16 clones of parents, F1 and F2 hybrids of Populus deltoides Bartr. ex Marsh. Ramet radial variations were nonsignificant, while inter-clonal variations due to interaction of clone/replication were significant for all the wood traits except vessel element length. Inter-clonal variations were significant only for fiber length and fiber wall thickness....     

橡胶树抗病增胶灵生产性试验报告

经勐腊橡胶分公司3年生产性试验结果表明:抗病增胶灵具有良好的增产效果,降低成本,减轻工人劳动强度,与自配常规复方刺激药剂相比,年平均净增产干胶0.38kg/株,净增产率7.34%,适于推广应用。     

17个阔叶树种在退化马尾松林的早期生长表现

对东莞莲花山自然保护区退化马尾松林林分2002年种植的17个3年生阔叶树种的树高、胸径以及冠幅进行测量和分析。结果表明，各个树种之间树高、胸径和冠幅生长均存在极显著差异（P〈0．01）。除红荷、桃花心木、仪花、格木和马占相思以外，其余12个树种树高与胸径生长表现出显著正相关（P〈0．05）。综合树高、胸径和冠幅3个指标对17个阔叶树种的生长数据进行聚类分析，桃花心木、火力楠、铁冬青、尖叶杜英和仪花生长较慢；枫香、格木、红锥、米老排、樟树、木荷、木棉和南洋楹生长速度中等；红荷和黧蒴生长较快；千年桐和马占相思生长迅速。总体而言。试验的17个阔叶树种对退化马尾松林的景观恢复取得一定成效。     

Regeneration of Pinus sylvestris in a natural pinewood in NE Scotland following reduction in grazing by Cervus elaphus

The occurrence of Scots pine (Pinus sylvestris L.) seedlings and saplings (<2.0 m in height and suppressed by grazing) and ground characteristics were recorded in a 300 ha block of natural pine forest in 1993. The density of red deer (Cervus elaphus L.) was then reduced by exclosure to approximately 3–4 deer km⁻², which is below the threshold at which pine regeneration should occur. Numbers and performance of pine seedlings and saplings were further monitored 2 and 4 years after exclosure. Numbers of young pine increased over time. In the three years with observations 97–99% of pine seedlings and saplings were recorded within 20 m of a seed source. Stepwise multiple regression was used to explore the relationships of pine establishment with plot characteristics for (a) all observation plots (n = 178) and (b) plots within 20 m of a seed source (n = 154). The factors most closely related to the number of pine seedlings and saplings in 1997 were, for (a), seed–source distance, vegetation height, blaeberry cover, slope and deer pellet-group density in 1993, all but the last having negative effects. For (b), vegetation height, blaeberry cover and slope were again selected predictors, and again had negative effects. Possible mechanisms by which the selected main effects may influence pine regeneration are discussed, the positive relationship to deer density being considered to reflect the creation of gaps in the sward suitable for germination. However, the amounts of variation explained in the models were low, being 16% for (a) and 13% for (b), reflecting the patchy nature and diverse age of the regeneration.     

黄龙县主要造林树种工程造林模式试验

以油松、侧柏为材料,在黄龙县试验研究了穴状整地、鱼鳞坑整地、带状整地等不同整地方式以及50cm×40cm×30cm、60cm×60cm×50cm、50cm×50cm×40cm等栽植穴规格对造林成活率、保存率以及幼树生长量的影响,结果为穴状整地和50cm×40cm×30cm栽植穴规格最好,建议该地工程造林选择穴状整地、栽植穴规格50cm×40cm×30cm。     

Influence of prior land use on wood quality of Pinus radiata in New South Wales,Australia

Wood quality data from 33 sites aged between 15 and 18 years old were analysed to determine the effect of prior land use (pasture, cleared grazing land or timber) on wood density, wood stiffness, fibre length and kraft pulp yield. Sampling sites covered 6 different forest areas within the estate. Prior land use (PLU) significantly affected wood stiffness, density and fibre length but not the kraft pulping traits. In contrast, differences were found between different forest areas for the kraft pulping traits plus fibre length but not for stiffness or density.     

Genetic variation in foliar nutrient concentration in relation to foliar carbon isotope composition and tree growth with clones of the F1 hybrid between slash pine and Caribbean pine

The objectives of this study were: (1) to quantify the genetic variation in foliar nutrient concentration in relation to foliar carbon isotope composition (δ¹³C) and tree growth of 122 clones of ca. 4-year-old F₁ hybrids between slash pine (Pinus elliottii Engelm var. elliottii) and Caribbean pine (P. caribaea var. hondurensis Barr. et Golf.) grown at two experimental sites with different water and nutrient availability in southeast Queensland, Australia and (2) to examine the potential of using foliar nutrient concentration of the 4-year-old tree canopies for selecting elite F₁ hybrid pine clones with improved nutrient-use efficiency (NUE) and water-use efficiency (WUE), and ultimately enhanced tree growth under ambient growing conditions. There were significant differences in foliar nutrient concentrations between two canopy positions (upper outer and lower outer canopy) sampled, between summer and winter, and between the two sites. This highlights that foliar nutrient concentrations are influenced by sampling and environment. Significant genetic variations in foliar nutrient concentrations were detected between the clones, between the female parents, and between the male parents of the clones in both sampling seasons at both sites. Depending on the nutrient concerned, canopy position, season, and site sampled, the clones accounted for 4.7–33.9% of the total variation in foliar nutrient concentrations, the clone female parents for 0–25.1% and the clone male parents for 0–28.6%. The site-by-clone interactions were statistically significant for foliar N, P, Mg, Cu, Zn, Mn, Fe and mineral concentrations at the upper outer canopy in summer, and for foliar N concentration in winter. There were significant, positive correlations between clone means of foliar δ¹³C and N concentration at the upper outer canopy in summer for the wet site, while clone foliar δ¹³C was also positively related to clone foliar N concentration at both canopy positions in summer for the dry site. This suggests that clone WUE as reflected in foliar δ¹³C may be improved by selecting elite clones with higher foliar N concentration and increased photosynthesis, leading to enhanced tree growth when both water and N are the major growth-limiting factors. This is supported by the positive correlation detected between clone tree height and foliar N concentration at the upper outer canopy for both sites. Thus, foliar nutrient (particularly N) concentration, together with foliar δ¹³C, may be useful for assisting in selection of exotic pine clones with improved NUE and WUE, and enhanced tree growth under the nutrient- and water-limiting environments.     

海岛困难立地抗旱措施对不同树种生长的影响

在舟山泗礁岛的松材线虫病危害迹地,通过完全随机区组设计研究了覆草、保水剂、覆草+保水剂3种抗旱保墒措施对舟山新木姜子(Neolitsea sericea)、全缘冬青(Ilex integra)、红楠(Machilus thunbergii)和石栎(Lithocarpus glaber)4树种容器苗造林保存率和生长的影响.结果表明:覆草、施用保水剂和覆草+保水剂3种蓄水保墒措施均能有效提高苗木生长量,其中以施用保水剂+覆草的效果最好,但不同处理对各树种的保存率没有显著影响;不同树种的苗高和地径生长幅度为:全缘冬青＞石栎＞红楠＞舟山新木姜子,保存率为:舟山新木姜子＞石栎＞全缘冬青＞红楠,通过隶属函数评价,供试树种适应能力为:舟山新木姜子＞全缘冬青＞石栎＞红楠.综合分析表明,在海岛困难立地植被恢复与重建过程中,可以优先选择覆草+保水剂保墒措施,应用舟山海岛地带性植被的优势树种的优质苗木进行造林.     

Prediction of annual tree growth and survival for thinned and unthinned even-aged maritime pine stands in Portugal from data with different time measurement intervals

An annual individual tree survival and growth model was developed for pure even-aged stands of maritime pine in Portugal, using a large data set containing irregularly time-spaced measurements and considering thinning effects. The model is distance-independent and is based on a function for diameter growth, a function for height growth and a survival function. Two approaches are compared for modeling annual tree growth. The first approach directly estimates a future diameter or height using well-known growth functions formulated in difference form. The second approach estimates diameter or height using a function in differential form estimating the increment over a year period. In both approaches, the function parameters were related to tree and stand variables reflecting the competition status of the tree as well as of a thinning response factor. Variable growth and survival rates were assumed in the modeling approaches. An iterative method was used to continuously update tree and stand attributes using a cut-off to convert the survival probability for a living or a dead tree. The individual tree diameter growth model and the survival probability model were fitted simultaneously using seemingly unrelated regression (SUR). Parameters of the height function were obtained separately as the number of observations for height was much lower than the number of observations for diameter, which may affect the statistical inference and the estimation of contemporaneous cross-equation error correlation inherent to the system of equations. PRESS residuals were used to evaluate the predictive performance of the diameter and the height growth functions. Additional statistics based in the log likelihood function and also in the survival probability were computed to evaluate the survival function. The second modeling approach, which integrates components of growth expansion and decline, performed slightly better than the first approach. A variable accounting for the thinning response that was tested proved to be significant for predicting diameter growth, even if the model already included competition-related explanatory variables, namely the basal area of trees larger than the subject tree. However, this thinning response factor was not significant for predicting height growth.     

Changes in the stand structure of a pine forest after rapid growth of Quercus serrata Thunb.

We studied the species composition and stand structure of secondary pine forests affected by pine wilt disease, caused by epidemic attacks of the nematode Bursaphelenchus xylophilus, in western Japan. Based on the species composition, the vegetation was divided into four types: (1) Cladonia rangiferina, (2) Wikstroemia sikokiana, (3) Quercus glauca, and (4) Gleichenia japonica. The sequence of types from (1) to (3) represents a successional series in accordance with topographical position. The relative basal areas of Rhododendron reticulatum and Juniperus rigida in the C. rangiferina and W. sikokiana types were larger than in the Q. glauca type. The relative basal areas of Q. serrata, Clethra barbinervis, and Eurya japonica in the C. rangiferina and W. sikokiana types were less than in the Q. glauca type. The mortality of light-demanding trees was higher in the Q. glauca type than in the C. rangiferina and W. sikokiana types. In stands that were severely affected by pine wilt disease, light was reduced and soil became moist after rapid growth of Q. serrata and other species which are not affected by the disease. The numbers of species and components of evergreen broad-leaved natural forests were decreased, because pine forests in the study area had been cut frequently and the land had degraded. Pine wilt disease has shifted the dominance of pine forests from Pinus densiflora to deciduous oaks such as Q. serrata and physical conditions seemed to provide a safe site for shade-tolerant plant species, which are components of evergreen broad-leaved forests. Moreover, the seed dispersal of evergreen oaks appears to be an important factor in the succession to evergreen broad-leaved forest in degraded areas.