吊丝球竹DD-1选育与推广研究

吊丝球竹DD-1是大渡河造林局近年选育的省级良种,通过吊丝球竹DD-1与原种吊丝球竹（Bam busabeecheyana）的分类学的差异分析、抗寒性等研究,结果表明：对低温的耐受性,与慈竹相当,明显优于杂交竹,可耐受-1.1℃以下的低温;吊丝球竹DD-1抗干旱性较强,在川中旱区种植成活率高于当地慈竹45.7个百分点;耐盐碱性尤为突出,在pH5.5~7.8均能正常生长,在pH值7.0~7.8的立地条件表现优异;在相同立地条件下,其生物量大大高于慈竹,DD-1单株平均重量20.1 kg,慈竹单株重量2.4 kg,DD-1重量是慈竹的8.37倍;比较与慈竹等4种竹子制浆抄纸性能,粗浆细浆出浆率综合评定优于慈竹,属于优良的造纸竹材;经营模式研究表明,DD-1栽植第4年,笋、材两项公顷平均收入可达34 500元~46 500元;综合研究表明：四川1 000 m海拨以下的山区可广泛种植。     

A study on the measurement for forest ecological benefit

IntroductionForesaw is importsnt part of national economy, notonly an industry but also a public welfare. Forestresource has ecological, economical and socialb6nedtS. At present, the study about forest ecologicalbenefit is mainly on measurement of physical quanhty, and less on measurement of economical quantity(Bat6man 1991, DWyer et al. 1992.) (how to transformphysical quantity to economical quantity). There existmany problems on research of measurement of forestecological benefitS. For ex…     

A new instrument for measurement and collection of quantitative samples of the litter layer in forests

The litter layer plays an important role in the maintenance of tropical forests. The evaluation of parameters such as thickness or water content can reveal forest conditions that are of global relevance (for example carbon stock) or of local importance such as the conservation of nutrients in native forests or plantations. However, there is no specific instrument or protocol for quantitative collection of the litter layer. We developed an instrument composed of two parts that permits measurement and collection of the litter layer, following a simple protocol. The method was tested in two forest types and we verified the greater accuracy and ease of use of the instrument compared to two other commonly used litter collection methods.     

中国笋用林文献分析及研究进展

对中国笋用林有关文献的数量、地区和主题分布等进行研究分析 ,发现中国笋用林有关文献分布具较强的地域性及聚散性特征。笋用林经营管理研究占文献量的 36 7% ,竹林丰产定向配套技术达到国际先进水平 ;基础研究占 1 9 0 % ,造林育种与笋加工方面的比例分别为 1 6 8%和 1 5 6 %。浙江在笋用林研究方面成绩突出     

林下经济的经营模式与发展对策

集体林权制度主体改革完成后,全国各地掀起了发展林下经济的热潮。从产业形态来看,林下经济主要有林下种植、林下养殖、林下产品加工、森林旅游等经营模式;从组织形态方面看,林下经济主要有林农独立经营、林业专业合作社、＂公司＋林农＂等经营模式。进一步促进林下经济的发展,需要加快推进集体林权制度改革的配套与深化,扶持建立一批示范基地和龙头企业,加强基础设施和销售平台建设,主打绿色、生态、有机的特色,树立品牌意识和原产地保护意识。     

基于度量误差的杉木与马尾松地位指数线性模型

地位指数法是当前立地质量评价中广泛采用的一种评定方法。在同一立地上,实现不同树种地位指数之间的转换,建立地位指数相关关系模型有助于立地质量的评定。然而,地位指数相关关系模型中其自变量和因变量均存在度量误差,所以采用常规的回归模型不合理或使用不便利。利用线性度量误差模型,以湖南省雪峰山杉木和马尾松地位指数为研究对象,建立了杉木和马尾松地位指数相关关系模型,并进行精度检验和模型适用性检验,其平均相对误差为5.391%,模型精度比较高。研究结果有助于不同树种间的立地质量评定。     

连续式平整度仪在高速公路中的应用

随着高速公路的大量兴修,一些新的试验检测技术得到了应用。本文对哈绥高速公路的检测 技术应用情况作了一些介绍,供大家参考。     

推行六合生态园区模式努力实现农业可持续发展

改善生态环境,实现农业和农村经济的可持续发展,是我们始终致力于破解一个难题。近年来,龙江县委、县政府大力实施"生态发展"战略,积极探索旱区农业未来发展的有效途径,通过全面推广整村推进结构调整的"六合模式"。走出了一条农牧结合,协调发展的生态农业建设之路。     

锯切表面粗糙度的综合评价

为了提高木材锯切表面的加工质量，探讨了微观不平度十点高度Rz在评价锯切表面粗糙度方面的可行性，并提出综合使用Rz和Ry两个参数来评价锯切表面粗糙度更加合理。     

厦门地区草坪主要害虫调查及其防治

1995～ 2 0 0 0年对厦门市草坪害虫进行调查 ,结果表明 :华南 (齿爪 )鳃金龟、华北蝼蛄、小地老虎、粘虫是近年来的主要害虫。文章对 4种主要害虫的生物学特性进行了简要记述 ,并提出了在生产上行之有效的无公害防治方法 ;分析了近年来害虫发生原因、发展趋势及控制害虫发生的对策     

森防工作如何应对林业发展新形势

面对我国启动实施的六大林业重点工程和林业五大转变，就森防工作如何应对林业发展的新形势，作了较为详尽的阐述。     

壳聚糖对种子萌发及幼苗生长的影响

本文采用不同浓度(0.1%、0.2%和0.3%质量浓度)壳聚糖(CS)溶液对马尾松、栾树、金合欢、刺槐、玉米、小麦进行漫种及幼苗处理.探讨壳聚糖对几种种子萌发及幼苗生理生化特性的影响.试验结果表明,各种子发芽率、发芽势、幼苗生长量和活力指数均高于对照;用壳聚糖溶液喷洒正在生长的幼苗叶片,其叶绿素、可溶性蛋白质含量均明显提高;且CS在一定范围内存在浓度效应,浓度为0.2%时处理效果最佳.     

论植物景观设计的可持续发展

本文论述了植物景观设计的“科学性、文化性、实用性、多样性和艺术性”等可持续发展特征,探讨了植物景观设计可持续发展的理念。     

A decision making model for investment and development of construction panels

A study was conducted to select the best alternative for the development of construction panels as well as investment in its manufacturing in Iran.Three alternatives are considered,cement-bonded wood composite product,substituted products(such as concrete panel) sandwich panel and a mixture of them.We apply the analytic network process(ANP) to achieve this goal.A hierarchy is designed to prioritize benefits,opportunities,costs and risks(BOCR) by using the Analytic Hierarchy Process(AHP) ratings approach.To evaluate the "control criteria" of the system,a control hierarchy is also created and prioritized by applying the Analytic Network Process(ANP).A total of four major control criteria in the system are prioritized where each one controls a decision network evaluated using ANP.The final synthesis of the system shows cement-bonded wood composite product is the best choice among three potential alternatives for the investment and development.     

SSJ—1型水力碎解机的设计

制作草炭容器的纤维浆料是首先经水力碎解机进行水力碎解后，再经系列工艺加工处理合成。该机在碎解纤维原料团过程中，采用了“高旋流水分解”和“挤排水分丝帚化”两工艺，并依据两工艺的原理，设计了以叶轮为主要工作部件和在动力传动过程中，实现两工艺间同时进行的相应传动机构。该设备的研制成功，不仅为草炭容器的生产提供了配套设备，也为碎解纤维团和纸料类纤维领域提供了一种新型、高效、节能的纤维分解设备。     

Declared value for the thermal conductivity coefficient of insulation corkboard

Summary This study presents the results of a set of tests for the determination of the thermal conductivity coefficient of samples extracted from boards of Insulation Corkboard (ICB) withdrawn from the usual production of the seven portuguese factories.These tests were carried out as a part of an interlaboratorial study integrated in the standardization program for cork of the sub-comission 4 of The National Technical Committee of Standardization (CT 16), in which participated the Cork Technological Centre (CTCOR), the National Laboratory of Civil Enginneering (LNEC) and the National Institute of Engineering and Industrial Technology (INETI). The purpose of this study aimed to contribute to the definition of the declared value of this thermal property to be included in the future European Standard (EN) specifying the characteristics of ICB for thermal insulating of buildings which is in preparation in the 88^Th Technical Committee of The European Committee of Standardization CEN/TC-88 (CEN 1995).In view of the results, the declared value of thermal conductivity proposed was 0.045 W/m. °C.     

Non-destructive measurement techniques for taper equation development: a study case in the Spanish Northern Iberian Range

In recent years, the technology for measuring the diameter and height of standing trees has improved significantly. These enhancements allow estimation of the volume of standing trees using stem taper equations, which traditionally have been constructed with data from felled trees, in an accurate and economically feasible way. A non-destructive method was evaluated with data from 38 pines and was validated with data from another 38 pines, both in the Northern Iberian Range (Spain). The electronic dendrometer Criterion RD1000 (Laser Technology Inc.) and the laser hypsometer TruPulse (Laser Technology Inc.) were used due to their accuracy and interoperability. The methodology was valid (unbiased and precise) measuring from a distance similar to the height of the tree. In this distance, statistical criteria and plots based on the residuals showed no clear advantage in volume estimation with models fitted with data from destructive methods against models fitted with data from the proposed non-destructive technique. This methodology can be considered useful for individual volume estimation and for developing taper equations.     

竹类种群动态理论模式的研究

从分析竹类各群的生命周期出发,并以大熊猫主食竹种冷箭竹的种群动态研究为例,建立了竹类种群动态的理论模式。     

A carbon balance model of peach tree growth and development for studying the pruning response

We modeled tree responses to pruning on the basis of growth rules established on unpruned trees and a simple principle governing root-shoot interactions. The model, which integrates architectural and ecophysiological approaches, distinguishes four types of anatomical organs in a tree: rootstock, main axis, secondary axes and new roots. Tree structure is described by the position of secondary axes on the main axis. The main processes considered are plastochronal activity, branching, assimilate production, respiration and assimilate partitioning. Growth and development rules were based on measurements of two unpruned trees. The model was used to simulate growth of peach trees (Prunus persica (L.) Batsch) in their first growing season. Assuming that the equilibrium between roots and shoots tends to be restored after pruning, the response to removal of the main axis above the twentieth internode in mid-July was simulated and compared to the response measured in three pruned trees. The model fit the unpruned tree data reasonably well and predicted the main traits of tree behavior after pruning. Dry matter growth of the secondary axes of pruned trees was increased so that shoot seasonal carbon balance was hardly modified by pruning. Rhythmicity of growth was enhanced by pruning, and might result from variations induced in the root:shoot ratio. Variation in pruning severity had greater effects than variation in pruning date. A sensitivity analysis indicated that: (1) root-shoot partitioning was a critical process of the model; (2) tree growth was mainly dependent on assimilate availability; and (3) tree shape was highly dependent on the branching process.