云南松化学采脂施用亚硫酸造纸废液、乙烯利试验报告

云南松是我省松脂生产的主要树种,也是全国三大采脂树种之一。为提高云南松立木产脂量和采脂劳动生产率,进而促进云南松松脂资源的充分利用,特参考亚硫酸造纸废液、乙烯利在马尾松等树种上试验的资料,于1980年7—12月在云南省石屏县大桥公社果腊村后山云南松纯林内组织小区试验。     

思茅松林分生物环境因子与产脂量关系的研究

松脂是思茅松产区林业生产的重要资源。本文通过各生物环境因子与产脂量关系的分析研究,泌脂量除受遗传基因控制外,还受海拔、林分密度、林龄、林分胸径的影响。产脂量随海拔、林分密度的增加而减少,随林分年龄、胸径的增加而增加。分别海拔、林分密度,林分年龄、胸径和四个因子建立的预测方程达极显著水平,均可在生产中应用。     

海寨林场采脂试点

通过对国营海寨林场进行采脂试点,得出了华山松、云南松单株年产脂量为1kg左右,松脂收益与现今劳动力报酬不匹配,难达到商品采脂要求的结论。为今后同海拔的高寒山区采脂提供一定的数据参照,同时指出了因区域的不同、采脂的出油量差异也较大,说明采脂也有风险,须慎重。     

林分密度及施肥对马尾松林产脂量的影响

采用长期定位观测,定时、定株收获的方法,研究了马尾松采脂林4种保留密度及16种施肥组合对产脂量影响。结果表明:不同密度松脂产量差异显著,随着密度的增大,单位面积松脂产量也随之增加,呈正相关关系,单株平均年松脂产量则随密度增大而减少,初步认定培育马尾松高产脂林保留密度C—D(750~900株.hm-2)较适合;在中等立地,施肥能有效增加松脂产量,不同施肥组合的松脂产量存在明显差异。较理想的3个施肥组合是:N250 g/株+P 500 g/株、P 1 000 g/株+K 300 g/株和N 250 g/株+K 150 g/株。同时分析了主要气象因子对松脂年产量变化的影响。     

云南松采脂技术

云南红河县垤玛乡、三村乡、车古乡、大羊街乡、架车乡、洛恩乡六个乡是云南松主要特产区。近年来，松脂价格不断上涨。受经济利益的驱动，在松脂采集工作中需要提高云南松采脂技术。为了充分利用保护森林资源和生态环境。推行合理采脂技术，提高松脂质量。促进松香生产可持续发展。文章简要介绍“下降式采脂方法”为广大脂农提供参考。     

云南松脂原料林发展现状、存在问题与对策研究

云南是一个松脂资源大省,主要产脂树种云南松和思茅松能采脂的林分面积和蓄积量均居全国的首位。松香、松节油产业在云南具有巨大的发展潜力和广阔的发展前景。通过对云南松脂原料林发展的现状、存在问题的分析研究,指出云南松脂原料林的建设应以人工林定向培育和提高松脂基地建设的科技贡献率为发展方向。发展云南松脂原料林基地应以市场以导向,选育松树高产脂良种开始,增加资金和科技投入,推广先进采脂技术,提高加工水平,实现松脂产业的可持续发展。     

马尾松不同径级产脂量及松脂成分差异研究

采用长期定位观测,定时、定株收获的方法,研究了马尾松9种径级与产脂量以及6种径级与松脂成分之间的关系。分析结果表明:不同径级产脂量差异显著,随着径级的增大,产脂量也随之增加,呈正相关关系,初步认定马尾松产脂林采割起始径级不小于18 cm;不同径级的松脂主要成分一致,各成分含量存在一定差异,含油量有随着径级增大而增加的趋势,α-蒎烯含量高是马尾松松节油的特征。     

湖南白蜡虫泌蜡量研究

比较了同一种源的的白蜡虫种虫在湖南不同产地以及不同种源的白蜡虫种虫在同一产地的泌蜡量。结果表明:相同种源的白蜡虫种虫挂放在湖南不同产地后,其蜡花厚度和单个雄虫泌蜡量在不同产地间均无显著差异;不同种源的白蜡虫种虫挂放在同一产地后,不同种源间的蜡花厚度存在着极显著差异,但单个雄虫泌蜡量则差异不显著。综合比较而言,云、贵、川等传统产地的白蜡虫种虫为优良种虫,而湖南本地生产的白蜡虫种虫可作为生产补充用种。     

马尾松产脂特性与其外部形态相关的初步探讨

<正> 马尾松是我国南方的主要采脂树种之一。人们在长期的生产实践中发现,马尾松的不同个体分泌松脂的能力有明显的差异。为探讨马尾松本身的形态特征与产脂量的关系,1979年在江西崇义县桐梓松脂林场采脂试验区对17个试验组50年生的524株树进行了调查研究,现将结果小结如下:     

不同产脂量云南松树脂道解剖学比较研究

为确定高产脂云南松的早期选择指标,采用石蜡切片法对不同海拔、不同产脂量云南松的针叶、树干韧皮部和木质部的组成性树脂道特征进行解剖观察,结果表明:高产脂与低产脂云南松的针叶树脂道个数、树干木质部树脂道密度、韧皮部树脂道大小及单位长度树脂道数量存在极显著差异(P＜0.01),但不同海拔之间无显著差异;高、低海拔高产脂云南松针叶树脂道数量分别比低产脂的高38.89％、30.34％,树干木质部树脂道密度分别高58.06％、48.48％,韧皮部树脂道大小分别高32.20％、29.73％,韧皮部单位长度树脂道数量分别高21.95％、38.51％.说明针叶树脂道数量、树干木质部树脂道密度及韧皮部树脂道大小3项指标,也可作为云南松产脂力评价的部分指标.     

Radial distribution of sap flux density in trunks of a mature beech stand

In a mature beech stand located in north-eastern Germany, xylem sap flux measurements were continuously performed during the 2002–2004 growing seasons. Ten representative trunks were studied using heated thermal dissipation probes. The measurements aimed at identifying principles governing radial profiles of xylem flux in beech trunks. The measurements were taken up to a trunk depth of 132 mm. The sap flow density in the pericambial xylem was found to vary among trees of different diameters, but was not considerably smaller in suppressed trees. A model for the radial distribution of sap flux density was formulated relating trunk radius and sap flow density. The model takes into account different trunk diameter. About 90% of the sap flux was found to occur in the outer two fifths of the trunk. Using this model, an adequate estimate of transpiration can be achieved at tree and stand level, even when the sap flux measurements are restricted to the outer trunk sectors.     

地形及整地方式对大扁杏幼树生长发育的影响

试验以4年生龙王帽为试材,研究了不同地形及整地方式对大扁杏幼树生长发育的影响。结果表明,两种不同坡向的3个坡位上对大扁杏幼树的生长发育影响不大;3种不同整地方式对大扁杏幼树有着显著的影响．其中以水平梯田整地的方式最为理想。     

Selection of feeding trees by capercaillie Tetrao urogallus in winter

Selection of winter feeding trees by capercaillie Tetrao urogallus was studied by sampling of needles of Scots pine Pinus sylvestris trees browsed by capercaillie and closely situated unbrowsed trees in 5 localities situated in the southern half of Norway. Browsed trees contained higher concentrations of N than unbrowsed trees but no differences in P were found among browsed and unbrowsed samples. Needles eaten by capercaillie were significantly lower in resin content than needles from unbrowsed trees. For tannin, no differences between browsed and unbrowsed trees were found. Results give evidence that capercaillie select needles richest in N when the resin content is low, but when high, the birds select needles low in resin. Thus, both N and resin play an important role in selection of winter browse by capercaillie.     

Usefulness of diurnal trunk shrinkage as a water stress indicator in plum trees

We compared seasonal changes in maximum diurnal trunk shrinkage (MDS) with seasonal changes in midday stem water potential (Psi(s)) over three years in plum trees grown in differing drip-irrigated regimes. In well-irrigated trees, day-to-day variations in Psi(s) and MDS were related to evaporative demand. Reference equations were obtained to predict MDS and Psi(s) values for well-irrigated trees as functions of environmental conditions. A decrease in plant water status toward the end of the growing season occurred even in the well-irrigated trees, probably reflecting a reduced volume of soil wetted by the drip irrigation system. Thus, for the prediction of Psi(s), different reference equations are required for the fruit-growth and after-harvest phenological periods. A seasonal change in the relationship between MDS and Psi(s) was observed, which compensated for the decrease in plant water status such that well-irrigated trees had similar MDS values during both the fruit-growth and after-harvest periods. The influence of tree size on the relationship between MDS and Psi(s) was also investigated. For tree trunk diameters ranging between 8 and 13 cm, MDS increased 13% for each cm of increase in trunk diameter, as a result of the thicker phloem tissues of the larger trees. This finding may allow extrapolation of Psi(s) predictions based on empirical relationships with MDS to plum trees of different sizes.     

Soil acidification under the crown of oak trees I. Spatial distribution

Thirty oak trees (Quercus robur L. sensu lato) growing on the same site were selected on the basis of their stem diameter (D_bh ≥ 0.625 m) and their effect on soil properties was assessed. Litterfall, old litter accumulation, acidity and buffering capacity of the A₁ horizon were measured at three distances from the trunk (0.4, 1.4 and 2.4 m) and in four directions (N, E, S, W). Results led to the conclusion that on average more acidification and litter accumulation occurred near the trunk base and in the north direction, but this general trend was far from being followed by every tree. The clay content of the soil was inversely related to acidification and litter accumulation. Interrelationships between soil organisms, crown leaching, bark substances and the parent rock are proposed as working hypotheses for the future of this study.     

Within-tree variation in transpiration in isolated evergreen oak trees: evidence in support of the pipe model theory

Within-tree variation in sap flow density (SFD) was measured in two isolated evergreen oak (Quercus ilex L.) trees growing in an oak savannah (dehesa) in southwest Spain. Sap flow was estimated by the constant heating method. Three sensors were installed in the trunk of each tree in three orientations: northeast (NE), northwest (NW) and south (S). Sap flow density was monitored continuously from May 18 to September 27, 1993. Daily values of SFD ranged between 500 and 4500 mm3 mm-2 day-1. There were significant differences in SFD between orientations; SFD was higher in the NE and NW orientations than in the S orientation. These differences were noted on both a daily and seasonal time scale, and were less pronounced on cloudy days and at the end of the drought period, when SFD was relatively low. Our results support the idea that branches of trees can be viewed as a collection of small independent plants.     

不同坡位8年生厚朴人工林生物量分配格局

对不同坡位8年生厚朴人工林地上部分和地下部分生物量及其分配率进行了调查分析。研究结果表明,从生长量来看,不同坡位平均胸径、平均树高及平均木单株总生物量均体现为下坡位〉中坡位〉上坡位;就各器官生物量分配率而言,不同坡位厚朴各器官生物量分配率表现为干〉叶〉枝;从平均木各径级根生物量分配率来看,各坡位均表现为骨骼根〉中根根〉大根〉小根〉细根;地上部分皮的总生物量表现为下坡位〉中坡位〉上坡位,地下部分不同径级根生物量分配率随坡位变化而变化,其中干皮生物量分配率表现为下坡〉上坡〉中坡,枝皮生物量分配率表现为下坡〉中坡〉上坡,大根及中根皮生物量分配率表现为中坡〉上坡〉下坡。     

Dynamics of transpiration, sap flow and use of stored water in tropical forest canopy trees

In large trees, the daily onset of transpiration causes water to be withdrawn from internal storage compartments, resulting in lags between changes in transpiration and sap flow at the base of the tree. We measured time courses of sap flow, hydraulic resistance, plant water potential and stomatal resistance in co-occurring tropical forest canopy trees with trunk diameters ranging from 0.34-0.98 m, to determine how total daily water use and daily reliance on stored water scaled with size. We also examined the effects of scale and tree hydraulic properties on apparent time constants for changes in transpiration and water flow in response to fluctuating environmental variables. Time constants for water movement were estimated from whole-tree hydraulic resistance (R) and capacitance (C) using an electric circuit analogy, and from rates of change in water movement through intact trees. Total daily water use and reliance on stored water were strongly correlated with trunk diameter, independent of species. Although total daily withdrawal of water from internal storage increased with tree size, its relative contribution to the daily water budget (approximately 10%) remained constant. Net withdrawal of water from storage ceased when upper branch water potential corresponded to the sapwood water potential (Psi(sw)) at which further withdrawal of water from sapwood would have caused Psi(sw) to decline precipitously. Stomatal coordination of vapor and liquid phase resistances played a key role in limiting stored water use to a nearly constant fraction of total daily water use. Time constants for changes in transpiration, estimated as the product of whole- tree R and C, were similar among individuals (~0.53 h), indicating that R and C co-varied with tree size in an inverse manner. Similarly, time constants estimated from rates of change in crown and basal sap flux were nearly identical among individuals and therefore independent of tree size and species.     

Crop load affects maximum daily trunk shrinkage of plum trees

We studied the effects of low fruit load (3-4 fruits cm(-2) of trunk cross-sectional area (TCSA), and high fruit load (6-7 fruits cm(-2) TCSA) on maximum daily trunk shrinkage (MDS) and trunk growth rates (TGR) over two seasons in plum (Prunus salicina Lindell) trees receiving full irrigation or deficit irrigation. Seasonal changes in MDS and TGR were compared with those in midday stem water potential (Psi(s)) and leaf stomatal conductance (g (s)). Crop load increased g (s) in fully irrigated trees approaching harvest. Although crop load did not affect plant water status in either watering regime, there were considerable differences in both MDS and TGR as a function of crop load. Compared with low-cropping [corrected] trees, MDS was 34% higher and TGR was 48% lower in high-cropping [corrected] trees. The differential responses of MDS and Psi(s) to crop load were a consequence of a higher MDS for a given Psi(s) in the high-cropping trees compared with the low-cropping trees. There was a linear increase in MDS with crop load, with a slope of 15.2 microm MPa(-1) per unit increment of crop load. In the fully irrigated trees, day-to-day variations in MDS were related to evaporative demand; however, the slope of the relationship between MDS and evaporative demand increased with crop load, indicating that different reference equations must be used to adjust for tree crop load when using MDS to determine plant water status and irrigation requirements.