人工栽培凹叶厚朴中厚朴酚与和厚朴酚含量的研究

人工栽培厚朴，其林龄、胸径及同株不同部位对厚朴酚与和厚朴酚的含量均有显著影响。     

不同地理种源高厚朴酚厚朴的筛选

从10个省、自治区收集了我国天然分布的15个厚朴种源3个类型,即:分布在云南的长喙厚朴,四川、重庆、湖北北部、贵州北部等地区的厚朴(川朴、紫油厚朴、油朴)以及分布在福建、浙江、安徽南部、湖南南部等地的凹叶厚朴,在福建省光泽县进行不同地理种源高厚朴酚厚朴的筛选。经过5 a的观察测试结果表明,凹叶厚朴在福建省光泽县表现最好,其中又以湖南道县、江西庐山、福建光泽种源表现更佳,具体表现在生长量大、厚朴酚含量较高。适宜在福建光泽等闽北地区种植。     

微波辅助提取厚朴叶中厚朴酚及和厚朴酚的研究

采用微波辅助法提取厚朴叶中厚朴酚及和厚朴酚,研究结果表明,微波功率中低火,酒精度50%,提取时间8min,料液比1∶40的提取条件最好。提取厚朴叶中的厚朴酚及和厚朴酚。厚朴酚、和厚朴酚以及总酚的提取率分别为91.31%、71.41%和86.53%;RP-HPLC方法较好,结果理想。     

响应面法优化厚朴酚及和厚朴酚的闪式提取工艺的研究

探索了闪式提取厚朴中厚朴酚及和厚朴酚的工艺。在单因素试验的基础上,选取对提取工艺影响较大的乙醇体积分数、提取时间和液料比3个因素进行Box-Benhnken中心组合设计,利用响应面分析法对工艺参数进行优化。结果表明:闪式提取法是一种快速有效提取厚朴中厚朴酚与和厚朴酚的方法,其最佳工艺条件为:乙醇体积分数92%,提取时间71s,液料比35∶1(mL∶g),样品厚朴粒径1.7mm。在此提取工艺条件下,厚朴总酚的得率为20.10mg/g(厚朴酚得率13.96mg/g,和厚朴酚得率6.14mg/g),与预测值20.32mg/g基本相符。     

不同种源厚朴酚类物质含量变异与遗传的初步研究

采集厚朴 5年生种源试验林共 13个种源 39个树皮样品 ,用高效液相色谱分析法 (HPL C)测定厚朴酚、和厚朴酚的含量。结果表明 :厚朴酚、和厚朴酚、厚朴酚类总量、厚朴酚 /和厚朴酚比例等品质性状在种源间均有显著或极显著的差异。叶先端小凸尖型的鄂西种源酚类含量最高 ,凹叶型的庐山种源最低 ,总含量前者是后者的 10 .34倍。以上 4个厚朴品质性状均受较强的遗传控制 ,其种源遗传力为 0 .7585～ 0 .94 6 5,且呈经向为主 ,经、纬双向地理变异     

厚朴酚与和厚朴酚类化合物药效的分子机制

厚朴中的主要活性成分厚朴酚与和厚朴酚表现出高效低毒的药理活性,具有开发分子药物的潜力。为给此类成分分子药理的深入研究提供参考和依据,综述了近20年来国内外关于厚朴酚、和厚朴酚类化合物药效分子机制方面的研究情况和研究进展;并在分析分子几何构象、电子结构、电化学反应行为及比较药理活性差异的基础上,对厚朴酚、和厚朴酚类化合物的构效关系和作用的生物靶分子进行了探讨。     

厚朴密度作用规律的初步研究

厚朴林分不同密度显著地影响胸径、树高、树冠的生长;密度增大,胸径、树高的速生年限缩短,树冠发育受阻,自然整枝加剧。18年生厚朴林,单株厚朴产量随着密度增大而递减,单位面积产量与密度关系不显著,但密度密的林分,因小径级数量厚朴增多而引起厚朴质量下降。因此,厚朴林的合理密植,应引起重视。     

厚朴丰产栽培技术

厚朴为我国特产,其树皮、根皮、花、果均可入药。树皮含有朴酚、四氢厚朴酚、异厚朴酚、木兰醇、生物碱、挥发油等成分,是重要的中药材,能治胸腹胀痛、血淤气滞、呕吐泻痢、宿食不消、咳嗽气喘、退热利尿等症状。芽可作妇科用药,种子含油率约35.5%,出油率25%,油可制作肥皂。     

香党坪厚朴人工林的调查研究报告

<正> 厚朴是名贵中药材树种,属木兰科高大乔木树种,近年来,由于厚朴收购价猛涨,农民采取了毁灭性的采伐,厚朴资源遭到严重破坏,据有关资料反映,目前可采伐的厚朴天然资源越来越少,厚朴人工栽培也只是零星栽培,很少有大面积的人工厚朴林,而对其人工林的栽培又缺少系统的研究,没有一套厚朴人工林栽培的技术措施。为了加快厚朴的人工栽培,为国家提供大量的厚朴药材,我们对香党坪人工厚朴林进行了调查研究,希望能对我县发展厚朴,提供一定的参考依据。现将调查内容及结果报告如下:     

厚朴研究综述

根据试验研究，综合厚朴的一些资料，论述了厚朴的分布、生物学特性、造林和采收加工技术，为厚朴的推广与发展提供依据．     

Comparative Study in Chemical Character and Fatty acid Compositions of Masked Civet''''s Fat and Nutria''''s Oil

IntroductionMaskedciVet(Paguma18vata),Mammalia,Viverridae,ismainlydiStributedinShanxi,Sichuan,Tibet,Yunnanprovinces,etc..Itsmeatisdeliciousandhasspecialflavor.Itiseasytoberaisedartificially,withhighproduCtivity.Nutria(MyocasterCOypus),Rodentia,Capromyidae,originatedinArgentina,Chili,etc.insouthAmerica.Itisakindofherbivoresfur-bearer.itsartificialraisinghassuchmeritsasdurablefurandlowcostandhighproduCtivity.MaskedcivetandnutriahavehigheconomicvalueandwideprospeCtofutilization.Atpresen…     

Repair and strengthening of timber cantilever beams

This research aims to study the feasibility of repair and strengthening of timber cantilever beams used in historic buildings. It is conducted to investigate the feasibility of using different valid materials and techniques to repair and strengthen timber cantilever beams in new and historic timber buildings. The study is performed in terms of structural performance as well as historic and architectural values. An experimental program of several different materials and techniques is executed. The results are driven in terms of initial cracking load, crack propagation for the tested samples at different loading stages, deflection values, and failure load for each repaired or strengthened material and technique. The main variables are timber types (new and historic), repair and strengthening materials (steel plates, Glass Fiber Reinforced Polymer wrap, and Carbon Fiber Reinforced Polymer laminates), repair or strengthening techniques (near surface mounted and externally bonded system), and cantilever length (1000 and 1250?mm). Test results indicated that using steel plates, glass fiber wrap, and carbon fiber laminates increases the value of failure loads and decreases the deflection at both; repaired and strengthened timber cantilever beams compared to control beams.     

Chemical composition of wood and its connection with wood anatomy in Betula pubescens

ABSTRACT

The connection between chemical composition and anatomy of wood is poorly studied. Abiotic and biotic growth conditions affect the synthesis of structural compounds and the anatomy of wood at the same time as they affect growth. In this study, the wood chemical composition, and connections between wood chemistry and anatomy were studied in downy birch (Betula pubescens Ehrh.) grown on four growth sites possessing mineral and peat soils. Lignin, holocellulose, extractive and ash contents, and effective heating value were analysed and compared with libriform fibre double wall thickness and lumen diameter, vessel size and number, and ray and axial parenchyma numbers. Measured lignin and extractive contents were exceptionally high and holocellulose content low. Correlations between wood anatomy and effective heating value were partly different on different soils. Correlations between holocellulose and anatomy were the opposite of the correlations between other chemical compounds and anatomy. The significant correlations between chemical composition and anatomy were commonly opposite in trees grown on peat than in trees grown on mineral soil. Particularly, vessel characteristics and fibre wall thickness correlated significantly with wood chemistry in trees grown on mineral soil. The connections between wood anatomy and chemistry proved to be soil-dependent.     

梣属(Fraxinus)植物果实的四种类型及其系统学意义

国内外重要的植物分类学与系统学文献均认为:木犀科和属(白蜡树属)植物只有2心皮的子房和果实。目前仅有2篇文献认为木犀科和属植物还具有3或3和4心皮的子房。作者在对属植物的果实进行研究时,发现属植物果实具有2心皮、3心皮、4心皮和6心皮4种类型,首次发现了属植物具有6心皮的果实。这一发现具有一定的系统学意义。     

Spatial patterns of Douglas-fir and aspen forest expansion

Spatial patterns, rates, and density of encroaching forests into adjacent grasslands have important implications for long-term land use management and resource planning. This study examines the effects of Douglas-fir (Pseudotsuga menzeisii) and aspen (Populus tremuloides) regeneration mechanisms on sucker and seedling spatial patterns, distance from adult trees, and density in encroaching forests. A total of 8,924 aspen suckers and 1,244 Douglas-fir seedlings were counted and mapped in 2,920 quadrats (5 m × 5 m) in 106 plots along a lower forest-grassland ecotone in the Centennial Valley, MT, USA. Sucker and seedling spatial patterns were analyzed using Morisita’s I index. Average sucker and seedling density per quadrat and distance from adult trees were estimated for each plot and compared between aspen-dominated plots and Douglas-fir-dominated plots using ANOVA tests. Aspen suckers were established in a clustered spatial pattern at a significantly higher density and a significantly shorter distance from the adult trees. In contrast, Douglas-fir seedlings were established in varying spatial patterns at a significantly lower density and a significantly greater distance from the adult trees. Forest encroachment into the adjacent grassland in the Centennial Valley is occurring in contrasting patterns and at varying rates and densities due to the difference in aspen and Douglas-fir regeneration mechanisms.     

Modelling impacts of changes in carbon dioxide concentration,climate and nitrogen deposition on carbon sequestration by European forests and forest soils

Changes in the Earth's atmosphere are expected to influence the growth, and therefore, carbon accumulation of European forests. We identify three major changes: (1) a rise in carbon dioxide concentration, (2) climate change, resulting in higher temperatures and changes in precipitation and (3) a decrease in nitrogen deposition. We adjusted and applied the hydrological model Watbal, the soil model SMART2 and the vegetation model SUMO2 to asses the effect of expected changes in the period 1990 up to 2070 on the carbon accumulation in trees and soils of 166 European forest plots. The models were parameterized using measured soil and vegetation parameters and site-specific changes in temperature, precipitation and nitrogen deposition. The carbon dioxide concentration was assumed to rise uniformly across Europe. The results were compared to a reference scenario consisting of a constant CO₂ concentration and deposition scenario. The temperature and precipitation scenario was a repetition of the period between 1960 and 1990. All scenarios were compared to the reference scenario for biomass growth and carbon sequestration for both the soil and the trees.     

Socioeconomic research in agroforestry: a decade in review

Agroforestry research in academia and government and non-governmental agencies began by focusing on biophysical aspects. As this science represents a series of practices implemented by individual farmers, it requires in-depth social and economic analyses to assess economic feasibility of agroforestry systems, factors influencing the adoption of agroforestry, monitor the relevance and effectiveness of investigations, and guide future research efforts. This study presents literature dealing with socioeconomic issues in agroforestry research from interdisciplinary peer-reviewed journals, book chapters, and gray literature from 1992 to 2002. Over 500 publications were analyzed to determine relative dominance of geographical regions, types of analyses, agroforestry technologies, and socioeconomic issues. Trends were examined over time and by region. Overall, the body of literature exhibits an increasing trend toward regional and analytical diversity over time. Some deficiencies of regional and thematic nature were observed, which included underrepresented temperate regions and technologies such as riparian buffers, as well as only a small number of papers dealing with gender and property rights. These suggest opportunities for future investigations.     

杜鹃花种子休眠打破技术的研究

以杜鹃花的两个种映山红（R.simsiiPlanch.）和蓝荆子（R.mucronulatumTurcz.）的种子为实验材料,用不同浓度的硫酸、有机溶剂和氧化剂处理种皮并分别处理不同时间,在培养皿中进行萌发对比实验;用赤霉素、层积及变温处理种子在培养皿中进行萌发的对比实验。结果表明,40%硫酸处理种皮20min、100%乙醚处理种皮20min、5%次氯酸钠处理种皮30min、层积处理及10%赤霉素处理24h均能有效提高映山红种子萌发的发芽率、发芽势和发芽指数;20%硫酸处理种皮10min、层积处理和赤霉素处理能显著提高蓝荆子种子发芽率、发芽势和发芽指数,100%乙醚处理10min能明显著提高蓝荆子种子的发芽率。     

杨树修枝理论和技术研究进展

杨树修枝是杨树速生丰产后期经营管理中一项重要的措施,本文综述了修枝对杨树生长、材质以及林下经济的影响。修枝对杨树树高、材积生长量的影响因树种、立地、修枝强度的不同规律不同;修枝会降低胸径的生长量,提高萌枝数量,但可以提高材质。修枝对材质的影响表现在尖削度减小、节子减少、形数和形率增加等。修枝可以增强林下作物光合作用,促进林下植物生长,提高产量;实践中,修枝强度、起始年龄、修枝季节应因树种而异。目前,对于杨树修枝的研究多为短期的、单方面的,系统综合研究尚需进一步加强。     

Risk assessment for biodiversity conservation planning in Pacific Northwest forests

Risk assessment can provide a robust strategy for landscape-scale planning challenges associated with species conservation and habitat protection in Pacific Northwest forests. We provide an overview of quantitative and probabilistic ecological risk assessment with focus on the application of approaches and influences from the actuarial, financial, and technical engineering fields. Within this context, risk refers to exposure to the chance of loss and typically involves likelihood estimates associated with outcomes. Risk assessment can be used to evaluate threats and uncertainty by providing: (1) an estimation of the likelihood and severity of species, population, or habitat loss or gain, (2) a better understanding of the potential tradeoffs associated with management activities, and (3) tangible socioeconomic integration. Our discussion is focused on threats identified as important influences on forest biodiversity in the region: natural, altered, and new disturbance regimes, and alien and invasive species. We identify and discuss three key challenges and opportunities specific to these threats and quantitative and probabilistic approaches to risk assessment: (1) endpoint selection and calculation of net value change, (2) probability calculations and stochastic spatial processes, and (3) evaluation of multiple interacting threats. Quantitative and probabilistic risk assessment can help bridge the current gap between information provided by general assessment and planning procedures and the more detailed information needs of decision and policy makers. However, management decisions may still fail to win public approval because important risks and issues can be missed or perceived differently by stakeholders. Stakeholder involvement at the inception of a risk assessment can help attenuate these problems. Stakeholder involvement also provides opportunities to communicate information that can influence public risk perceptions and attitudes.