山丹河城郊段河岸植物景观设计

基于植物造景的基本原则与方法,以甘肃省张掖市山丹县山丹河污水处理厂至祁家店水库段河道的河岸植物景观设计为例,分析项目地概况、主要植物种类选择,分别提出河岸护坡植物及湿地植物的配置原则及方法,采用乔、灌、草搭配及不同植物的色彩搭配进行植物配置。对项目地右岸、左岸生态护坡植物及湿地植物进行种植设计,运用植物景观改善山丹河的环境现状。     

汕头市水库库区维管植物资源调查分析

文章介绍了广东省汕头市水库库区有维管植物142科384属592种,其中野生维管植物有139科370属570种,包括药用植物468种、观赏植物358种、油脂植物65种、纤维植物47种、植物蛋白质和氨基酸植物44种、鞣料植物37种、芳香油类植物29种、植物胶与果胶植物17种、淀粉植物14种、维生素类植物6种、植物色素类植物5种、糖与非糖甜味剂植物4种、树脂类植物4种、橡胶与硬橡胶植物3种,国家重点保护野生植物和珍稀濒危植物资源6种,并对其资源特点进行了分析、对其开发利用和保护提出了建议。     

植物的传统文化与园林应用——植物风水学中的植物造境

植物传统文化在园林景观中根深蒂固,应用植物来造境历史悠久。植物民族情结、植物象征意义及植物风水学等历史遗留下来的植物传统文化在当今环境营造中有着其独特的景观文化效应,而植物风水学中的植物配置理论更有其特殊的心理调节作用。许多植物在风水学中有自己的特殊含义及完整的配置理论体系,风水植物摩肩接踵间,"聚气造势",其"气"、"势"下的景观环境科学、宜居。本论文通过对植物传统文化,尤其是植物风水学文化的探究,挖掘隐藏在植物背后的潜在能量,并研究其能量与人居园林生境的关系。     

植物源农药的研究和应用进展

综述了植物源农药(包括植物源杀虫剂、植物源杀菌剂、植物源除草剂)的研究和开发应用现状。较详细地介绍了几种典型杀虫植物注要包括楝科植物、豆科鱼藤属植物、卫矛科植物)的杀虫机理和开发应用情况,并讨论了植物源杀虫剂今后研究的几个热点:生物技术在植物源杀虫剂研究中的应用;植物源光活化毒素的研究;杀虫植物资源的进一步调查研究。与植物源杀虫剂相比,植物源杀菌剂和除草剂的研究和应用要少得多。然而目前人们已经在植物体内发现许多具有杀菌、除草活性的物质,因此开发植物资源合成杀菌剂和除草剂具有巨大的潜力。     

九万山自然保护区植物资源

在对九万山自然保护区森林植被调查的基础上,介绍其中主要的材用植物、纤维植物、芳香植物、油脂植物、淀粉植物、饲料植物、园林观赏植物、稀有濒危保护植物、药用植物、橡胶植物等18类资源植物,提出植物资源保护与利用建议。     

茂兰喀斯特森林区的野生经济植物

贵州茂兰喀斯特森林区位于贵州省南部荔波县境内,为亚热带喀斯特森林生态系统。该区内有维管柬植物143科501属1203种,其中有经济植物1268种,隶属于184科568属;按用途分材用植物、油料植物、药用植物、观赏植物、工艺植物、绿化植物、纤维植物、香料植物、果实加工植物、蜜源植物、染料植物、薪炭植物、栲胶植物等13类。本文中,例述了一些有代表性的、经济价值较高的植物种类,分析了该区经济植物的特点及存在问题,提出了合理开发利用的措施和建议。     

呼和浩特市彩叶植物种类及园林应用研究

文章首先介绍了彩叶植物的定义和分类;其次,在实地调查的基础上总结呼和浩特市园林绿地中现有常色叶植物、秋色叶植物、春色叶植物、双色叶植物和斑色叶植物等彩叶植物资源;最后,通过对彩叶植物应用形式和存在问题的分析,提出几点个人建议,希望在呼和浩特市园林绿化中合理应用彩叶植物提供帮助。     

湖南省通道县植物资源调查

对通道县植物资源作了调查统计,结果显示：全县有高等植物251科981属2589种,其中国家一级重点保护植物5种,国家二级保护植物27种,湖南省重点保护植物48种,兰科植物62种,是湖南省植物资源最丰富的县之一。     

植物生物技术在茶树生产中的应用现状与展望

综述植物组织培养、植物基因工程、植物细胞工程等植物生物技术在茶树生产上的应用现状 ,展望其他植物生物技术在茶树生产上的前景 ;指出茶树植物生物技术的研究与推广工作比较落后 ,开展这项工作任重道远     

绿地植物配置中的花色与时令效果

用植物进行造景时,应充分发挥植物的观赏性功能,创造良好的生态环境,求得植物与植物之间,植物与环境之间,植物与时令之间的最大协调,使各种植物和谐共存,群落稳定发展,以达到调节和美化自然环境的目的。     

坚持和完善森林资源管理制度 保障和促进林业持续快速发展

概要阐述了森林资源在维护生态平衡、促进可持续发展中的重要作用,简要分析了当今全球和我国森林资源状况,全面总结了建国以来我国森林资源管理取得的成绩和经验,深入揭示了当前我国森林资源及其保护管理存在的问题和原因,系统介绍了我国森林资源管理的基本政策和制度。按照《中共中央国务院关于加快林业发展的决定》要求,对今后一个时期我国森林资源管理的思路、目标、任务提出了一些设想和建议。     

Short-term Effect of Thinning on Pinus sylvestris Damage and Sporulation Caused by Cronartium flaccidum

The short-term effect of thinning on cronartium rust on Scots pine ( Pinus sylvestris L.) was investigated in a stand of Scots pine (artificially seeded and in the pole-stage) severely infected by the stem-rust fungus Cronartium flaccidum (Alb. & Schwein) G. Winter. The disease rate (the number of old and fresh infections) was recorded before thinning, after which all trees with a resin-top as well as all individual branches with sporulating lesions were removed from the thinned plots, while the comparison plots remained non-thinned. The numbers of sporulating lesions were recorded on the plots annually for 2-5 yrs after thinning. Thinning had no significant short-term effect on the year-to-year relative number of sporulating lesions. The relative number of sporulating lesions, however, increased in both thinned and nonthinned trees, varying significantly from year to year. Thinning had no significant effect on the year of formation of the shoot bearing annual sporulating lesions, the duration of sporulation or the growth of the fungus along the infected shoot in perennial lesions during the first 5 yrs after the treatment.     

Concentrations of Cadmium,Lead and Mercury in Different Soils in Two Swedish Forest Catchments

Accumulation of cadmium (Cd), lead (Pb) and mercury (Hg), as affected by organic matter content, pH of different soil compartments and the physicochemical properties of each metal, was studied in different soil types within two forested catchments of the Norway spruce (Picea abies - Vaccinium myrtillus) type. Independent of soil type, the highest metal concentrations were found in the organic layers of the soil, usually in the surface soil. The concentrations in the upper part of the mineral subsoil were about one-fifth to one-tenth, or less, of those in the organic surface soil. Concentration maxima in the B-horizon were more pronounced for Cd and Hg than for Pb. When comparing soil types, the highest concentrations of Cd were found in the less acidified fens in the discharge area, while for Hg and Pb the highest concentrations usually occurred in the mor layer of the well-drained Podzols. For all metals, the soil types with the largest accumulation had concentrations up to 2-3-fold higher in the organic layers than those with the smallest accumulation.     

Photosynthetic Characteristics of Ash and Larch in Mixture and Pure stands

IntroductionDuringthepasttwodecades,studieshaverevealedthatgrowingash(Fnainusmandshurica)andlarch(LarlksPP.)togetherinaproperwaycanincreasetheproduc-tivityQfthestandsI"'}'-'].Theyieldimprovementmechanismsattributetotwoaspects,i.e.,theabovegroundandundergr…     

用碘结晶法测量针叶树材的微纤丝角

采用碘溶液和氢氧化钠两种溶液的混合液处理针叶树材管胞弦壁切片，并用干燥法脱除切片胞壁水，对碘结晶法测量木材微纤丝角的方法进行改良．结果表明，切片的木素脱除干净彻底，次生壁微纤丝之间易形成空隙，有利于碘离子进入其中形成碘结晶，可清晰地观察到微纤丝的走向，有利于有效而准确地测量微纤丝角，与改良前进行比较，具有省时省力，节约经费的优点．     

Improvement of dispersing property of sodium sulfite-formal-dehydeanthraquinone pulping effluent by treatment withCoriolus versicolor

A strain of the fungusCoriolus versicolor was inoculated periodically into potato dextrose agar (PDA) slants containing the effluent to enhance the natural ability to grow in the effluent. The acclimated strain grown in the 50% effluent-containing PDA slant and the original strain were employed to treat the effluent. The acclimated strain could grow in a higher concentration of the effluent than the original unacclimated one. Both the original and acclimated strains improved the dispersing ability of the effluent, especially the acclimated strain because of its higher laccase secretion. The dispersing ability of the SFP effluent was improved to a level comparable to a commercial lignosulfonate product because it was strongly polymerized by the fungus. During the fungal treatment, more than 50% of the sugars were removed from the effluent, thereby increasing the purity of the SFP lignin product.This work was presented at the 48th annual meeting of the Japan Wood Research Society, April 3–5, 1998, Shizuoka, Japa     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Effect on maize growth of the interaction between increased nitrogen availability and competition with trees in alley cropping

Maize growing next toErythrina hedgerows had 44% lower biomass (p<0.01) and 35% lower N content (p<0.1) than maize growing in the middle of the alleys. Maize growing next toGliricidia hedgerows had the same biomass but 56% higher N content (p<0.1) than maize growing in the middle of the alleys. However these differences did not develop until 2 months after sowing of the maize.Spatial variability in soil nitrogen mineralization and mulch nitrogen release did not explain any of the differences in growth or N uptake of the maize with respect to distance from the trees. It is hypothesized that the slower growth of the maize next to theErythrina trees after 2 months is due to increasing light and/or nutrient competition from the trees as the trees recover from pollarding. The apparent lack of competition fromGlirigidia may be due to different rates of regrowth or different shoot and root architecture.A theoretical model is described demonstrating that if a crop is to take advantage of the higher nutrient availability under alley cropping it must complete the major part of its growth before the trees recover significantly from pollarding, and start competing strongly with the crop.     

Modelling of adequate pretwist for obtaining straight timber

Abstract

Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists.     

基于GIS和RS数据的地统计学方法在水质评价中的应用

基于地理信息系统和Landsat TM (ThermalMapper)数据 ,本文应用地统计学的方法分析了肯尼亚Naivasha湖的水质。通过分析比较不同的插值法 ,最终分别采用普通克里金 (OrdinaryKrigging)和各向异性克里金 (AnistropyKrigging)方法绘制Naivasha湖水的深度和浊度图 ,并计算了湖水总容量。结果表明 ,湖水总容量为 3893371 99m3 ,以 30 (未知单位 )作为阈值 ,湖中净水和浊水的容积分别为 36 774 1 2 72m3 和 2 1 5 95 92 8m3 。