不同种源西南桦在云南景东的生长差异

从西南桦分布区内选择的13个种源在南亚热带山地进行筛选试验的结果表明:不同种源在生长、产量、形态 特征上都有很大差异。以胸径、树高、材积和干形等为指标,用坐标综合评定方法对13个不同种源进行综合评定, 结果表明:潞西、屏边和镇源3个种源生长和形态等各种特征都比其它种源好,位列前3名,是当地适生的好种源; 西马、龙陵和百色种源表现较好,属可利用种源;腾冲和西莲种源表现差,不好利用;平果、凭祥、靖西、景洪和田林5 种源表现一般,最好不发展。     

不同强度人为干扰对马尾松生长的影响

不同强度人为干扰15a后,经解析木分析表明,轻度干扰林分中马尾松的胸径、树高、材积均保持良好的生长趋势,总生长量比中度干扰和重度干扰林分高,连年生长量和平均生长量在幼龄期也高于后二者,重度干扰林分的各要素生长量均增长缓慢。这些结果表明超过一定限度的人为干扰阻碍了林木的生长发育。     

火炬松育苗技术研究

火炬松育苗试验结果表明:火炬松大田育苗最佳的处理组合为苗木密度100~150株/m2、芽苗截根处理以保留芽苗主根长的50%、接种厚环乳牛肝菌Sg;火炬松容器育苗最佳的基质配方体积比为火烧土30、过磷酸钙2.5或5.0、深层红壤35、松林表土35两种组合;菌根化处理是火炬松容器育苗行之有效的措施,菌根化对容器苗苗高、地径的生长有比较明显的正效应。     

Stand density and growth of Norway spruce (<Emphasis Type="Italic">Picea abies</Emphasis> (L.) Karst.) and European beech (<Emphasis Type="Italic">Fagus sylvatica</Emphasis> L.): evidence from long-term experimental plots

On the basis of nine Norway spruce (Picea abies (L.) Karst.) and ten European beech (Fagus sylvatica L.) thinning experiments in Germany, for which both residual and removed stock had been registered first during 1870, I scrutinize how moderate and heavy thinning from below (B-, C-grade) affects the production of merchantable volume compared with light thinning (A-grade). In relation to A-grade, cumulative merchantable volume (CV) of B- and C-grade amounts in average to 103–107% in juvenile and to 97–102% in mature Norway spruce stands. The corresponding findings for European beech are 101–106% and 94–102%. CV of individual stands varies between 89% and 130% for Norway spruce and 73% and 155% for European beech (CV of A-grade = 100%). These findings are substantiated by the relation between stand density (SDI) and periodic annual increment (PAI). On the B- and C-grade plots of spruce and beech, respectively, SDI was reduced down to 41–91% and 31–83% of the A-grade. When SDI is reduced in young stands, PAI follows a unimodal curve. Norway spruce’s PAI culminates in 109% if SDI is reduced to 59%; European beech’s PAI culminates in 123% when density is reduced to 50%. Whereas Norway spruce’s growth reacts most positively on thinning under poor site conditions and with increment reduction on favourable sites, European beech behaves oppositely. With stand development the culmination point of the unimodal relation moves towards maximum density, so that in older stands PAI follows the increasing pattern, which is the left portion of a unimodal curve. A model is presented which apparently unifies contradictory patterns of stand density–growth reactions by integrating relative stand density, average tree size and site fertility effects, and makes the findings operable for forest management.     

印楝实生苗年生长规律研究

研究了1年生印楝实生苗生长动态、苗木生物量积累与分配模式以及苗木生长与气象因子的关系,结果表明:印楝苗的年生长规律符合Logistic曲线特征,据此方程可以建立苗高、地径与生长时间的拟合模型,结合二次多项式对苗木连日生长量的动态模拟,可将苗木生长划分为4个阶段:出苗期、生长初期、速生期和生长后期,其中处于速生阶段苗木的高和地径生长量均超过全年总量的70%,地径处于生长初期阶段的时间短于苗高,但生长量占全年总量之比是苗高的2倍;苗木生物量积累与苗高和地径的相关性极为密切,其中地上部分生物量占全株的69.1%,全株含水量是干质量的1.58倍;在制约苗木生长节律的气象因子中,偏相关分析表明:温度是苗木生长的主导因子.     

云南小粒咖啡优良品种比较试验及丰产栽培示范

以德宏热带农业科学研究所咖啡种质库选出的13个小粒咖啡品种为材料,在云南省4个不同的生态类型区建立咖啡优良品种比较试验区和丰产栽培试验区,以验证各品种的生长、产量和品质等优良特性,和在不同生态类型区的稳定性,试验结果筛选出CIFC7963、28号可在云南适宜植区大规模种植;T8667、T5175、CatimorP88、CatimorP128等4个品种可以扩大种植。景洪试验点年均气温高(22.4℃),超过小粒种咖啡对最适年均温(19～21℃)的要求,不适宜种植小粒种咖啡。     

Leaf conductance of primary and mature leaves ofPinus roxburghii: A comparison

We used a null-balance porometer to measure leaf conductance of mature and primary leaves of natural seedlings, saplings, and trees ofPinus roxburghii (chir) during autumn at four sites at 1,320–1,930 m elevation in the central Himalaya of India. Our hypothesis that primary leaves had higher leaf conductance than mature leaves (needles in fascicles), based on measurements in other pines, was rejected. Comparisons on the same saplings and seedlings showed lower leaf conductance for primary leaves than for mature leaves. Primary leaves on seedlings and saplings also did not consistently have higher leaf conductance than mature leaves on near-by trees. Mature leaves on seedlings, however, did often have higher conductance than mature leaves on nearby trees. Mean values for leaf conductance (mmol m⁻² s⁻¹, based on total leaf surface area) ranged from 42–82 for mature leaves on trees, 60–121 for mature leaves on seedlings, and 28–67 for primary leaves on seedlings. Compared to published values for other pine species, conductance of mature leaves ofP. roxburghii is relatively low. Funding for this study was provided by grants from the United States National Science Foundation, INT-9312052 and INT-9404043. We appreciate the review of an early draft by Barbara Bond.     

红松高生长模型的研究(英文)

高生长模型是定量研究树木生长过程的有效途径,本文应用双曲线方程、Logistic方程、三个参数的Richards方程及四个参数的Richards方程对红松的高生长进行了研究。结果表明四个参数的Richards方程在模拟红松高生长时最为合适,且当其参数取不同的数值时,该方程可转化为其它理论方程。在使用四个参数的Richards方程时,可根据立地条件事先给定树高最大值,这样可使模型更符合实际情况。此外,文中还对一种以固定年龄时实际树高为参数值的模型进行了讨论,该模型对于计算给定树木的高生长将更为有效。     

The effect of late season damage on the apical bud development of Scots pine seedlings

The effect of Lygus rugulipennis Popp. feeding and artificial damage on the apical bud of Scots pine (Pinus sylvestris L.) late in the growing season was studied on two-year-old seedlings. Lygus feeding in late July and August caused inhibition of bud formation in the subsequent year's shoots, which led to loss of apical dominance and formation of interfascicular buds. Mechanical damage caused by piercing the apical bud with a needle in July, August and October produced scars and malformations on subsequent year's shoots and buds, but did not inhibit bud formation. Damage to the apical meristem could not be detected visually on the dormant bud before shoot elongation.     

杉木幼林年生长节律划分和相关气候因素分析

杉木幼林年生长规律及气候因素对生长的影响,是合理制订杉木产区区划,改善杉木造林规划设计布局,正确实施经营管理措施的基础。 本项研究,将全国杉木西部试区的四川高县作为试验点,从1985～1988年,连续4年在5～8年生不同密度林分中,作了胸高直径及树高生长的旬期定期观测。经对这些实验数据作均值处理,聚类分析,关联分析和多元回归分析结果表明:对生长在中国杉木中带西部产区,处于中亚热带湿润气候区环境条件下的杉木幼林年生长规律的论证及对影响生长的主要气候因子的分析判断和预测,具有可靠性和区域代表性。