Review on Wood Discoloration and its Control

Wood color is an important factor to determine wood impression. It is also the most vivid and active factor in furniture and interior decoration design. It is an important index to evaluate wood commercial value, and strongly influences wood sale competition power. Wood discoloration is the change of normal wood color. Plywood, veneer, furniture and decorative wood products have some limits on wood discoloration, and export products have also strict limit on it. Discoloring of biomass wood is…     

Current Research and Development on Deformation and Fixation of Bended Wood and Wood-based Composites

There are many advantages of bended wood,such as good-looking shape,simple process and low cost.The product,however,is easy to get recovery,which is urgent to be dealt with.This paper concludes the features of deformation and recovery of bended wood and wood-based composites and summarizes four treating methods to keep dimensional stability.Compared to bended solid wood,some elementary perspectives on the research of bended wood-based composites are presented.The purpose of this paper is to suggest:1)to investigate the optimum heating time and temperature that bended wood and wood-based composites need from the formation of deformation to the recovery and to the permanent fixation,according to its changes of dimensional stability such as curvature radius;2)to measure the composites comprised of wood and adhesives on the changes of stress relaxation,dynamic viscoelasticity and crystal1ization field;3)to quantitatively analyze changes of the major components in wood cell wall polymers as well as the composites under heat/steam treatment and untreated conditions.It will be helpful for subsequent research to clarify on the mechanisms of permanent fixation of bended wood and also contribute to that of wood-based composites.     

European standards on durability and performance of wood and wood-based products – Trends and challenges

Abstract

Standardization work in the field of wood durability and preservation is managed, at the European level, by the technical committee TC 38 ‘Durability of wood and wood-based products’ of the European Committee for Standardization (CEN). Producing sustainable wood-based materials is challenging. A crucial aspect of their provision is reliable standards that take consideration of both the expectations of end-users and the broad set of parameters that may influence the service life of wooden components such as exposure to moisture, climatic variations and design. In order to reach these objectives, most CEN/TC 38 standards are currently being revised based on the recent scientific, technological and legal developments in the field of wood protection. There is an increasing need for performance classification of wood products in construction and to radically consider how wood durability test methods and standards can inform on service life and how they might be translated into a performance classification system. This paper describes the changes during the past 5–10 years in Europe and how the trajectory of standards development is now on a different pathway. Classification and service life demands are described as well as current approaches to consider key issues such as material resistance, moisture risk and adaptation of existing standards.     

Analysis and Comparison on Anatomic Features and Properties of 4 Acacia Species

INTRODUCTION Acacia are widely distributed in tropical and subtropical regions in China. Because of certain climatic similarity in China and Australia, acacia were introduced from Australia since the 1960s as all purpose tree species which also play important roles in plantation forestry, soil and water conservation and landscaping (Fang Guigan et al. 1995). In recent years, more than 0.11 million ha of acacia palantations have been established in southern China, where some major specie…     

Mechanisms and Techniques of Agroforestry Ecosystem on Snail Control and Schistosomiasis Prevention

INTRODUCTION Schistosomiasis, snail fever, is a sort of parasite disease chronically, wildly and seriously injuring human health, especially in developing countries. WHO statistics indicated that about 200 million people in 74 countries, accounting for one third to a half of the population in disease prevailing area, has been suffering from epidemic snail fever. China is one of the countries suffering from snail-fever most in the world, about 100 million people at the risk of suffering fr…     

Eucalypt Wood Anatomical and Physical Properties and Their Effects on Plywood Veneer Quality

In order to better understand the reasons why eucalypt veneer checks easily and severely, wood samples of three eucalypt species were selected, and their anatomical and physical properties were examined according to conventional methods and the national standards. The effects of variances in cell wall thickness of wood fibre and vessel, and diameter of the cell lumen as well as the tissue ratio on the quality of plywood veneer were analysed. The results show that： 1） There is a great difference in fibre cell wall thickness and diameter of the cell lumen between early wood and late wood of Eucalyptus delegatensis. 2） E. obliqua has a high wood fibre tissue ratio and the thickest fibre cell wall, but the difference inthe fibre cell wall thickness between early wood and late wood is the smallest. 3） The wood fibre tissue ratio of E. regnans is smaller than that of E. obliqua, and its wood fibre cell wall isthe thinnest and there is only a very small difference in fibre cell wall thickness between early wood and late wood. The difference inthe diameter of wood fibre cell lumen among early wood, transition area and late wood is also small： 4） E. delegatensis has the highest tangential shrinkage rate and radial-tangential shrinkage rate, andE. obliqua has the lowest. It is the variability of wood anatomical properties of these species that cause the difference in the veneer shrinkagei and then affects plywood veneer quality.     

A Study on the Effects of Insect Pests and Diseases on Intensively Managed Plantations

Basedon the results of monitoring the environment of China National Afforestation Project (NAP) and the investigation on insect pests and diseases in 1.2 million ha of plantations, the author elaborates the areas, species and causes of insect pests and diseases occurring in the project's areas and provides fundamental theory for guiding environmental protection and plantation establishment in a sound way. Since the project's activities strictly follovved the guideline of environmental protection in past five years, little losses were caused by some commonly insect pests and diseases.     

Comparative Study on Public Forest Management and Forest Law in France and USA

Though public forests in countries take up a small portion of forests, their importance in respect of environmental side looms large gradually. This paper studies and compares the public forest management and forest laws in France and the USA, attempting to explore the forest operation practice in both countries and the emphasis of the law governing forest management, so that a lesson can be drawn for us to learn in China.     

Survey and Analysis on Forestry Production of Community Population

Forestryisanimportantindicatorofacountryandregion'scivilization,alsoanimportantcomponentofthecountry'snationaleconomy;theparticipationofbroadmassestoforestryproductiondirectlyinfluencethemtomakethemostoftheirforestryproductioninitiativesandintegratedbenefitsoflocalforestry.Withtheincreasingdevelopmentofsocietyandeconomy,theopportunitiesofcommunitypeople'sparticipationofforestmanagementactivitiesareincreasing,anditsscopegraduallyenlarging,atthesametime,anumberofnewproblemsandconflictsarealsoemer…     

Impact of Demographic Structure on Paddy and Forestland Management

INTRODUCTIONChina resorts to socialist public ownership of land.In present, the ownership of land belongs to the stateand collectives. The ownership of land in China refersto the right that the owners of land can possess theland, use the land, get some interest from the landand dispose of the land according to laws. The 4sections of ownership of land can be combined as awhole, and also can be separated to carry out. Beforethe Third Plenary Session of the 11th CPC(Communist Party of Ch…     

Development of Electroless Copper and Gold Plating on Wood

The use of more and more electron products requires interior wood products to have the performance of electromagnetic shielding. One of the ways to realize it is to introduce the chemical plating which has already been developed in electron industry into wood processing. The paper clarifies the mechanism of electroless copper and gold plating and its application to wood. It emphasizes the development and technology of electroless copper and gold plating on wood. Meanwhile, it points out that it is highly feasible to take this technology into effect.     

Present research on the composition and application of lac

Lac is a natural polymer with atoxigenic, renewable, and naturally degradable characteristics. Nowadays, more and more attentions are paid to environment protection and resource conservation, so it has great significance to study the composition and application of lac. The paper summarizes the research of lac composition and emphasizes on the present research of lac resin. The applications of lac are also introduced. In addition, some suggestions are proposed, which is expected to provide some scientific references for further studies of lac.     

Study on Balance between Supply and Demand for Timber and Timber Products in China

INTRODUCTION Because China is deficient in forest resources, and the forest has the characteristics of low quality, uneven distribution, slow growth and severe situation of ecological environment, the ecology construction has become the first requirement in society and with the implementation of the “Natural Forest Conservation Program”, Chinese forestry is in the historic transition from timber production to ecological construction. Therefore, the timber production in China increases…     

Research on TemporaI and Spatial Patterns and Dynamic Laws of Soil Water at Eco-tope between Oasis and Desert

Based on long term and stationary research, the temporal and spatial patterns and dynamic laws of soil water content in Minqin desert area were studied. Some results are as follows:(1)The change of soil water content in different years is not obviously in shrub sand dune of Nitraria sibirica and Tamarix ramosissima, but it was great in shifting sand dune, the maximum is 2.538%; (2)The season dynamics can be divided into three stages: accumulating, consuming and stable; (3) The vertical change of soil water content distribution is obvious, i.e., decreasing with the depth; (4)Compared with the lower slope and middle slope,the upper slope has higher soil water content, the maximum is 15.408%.     

Study on Chemical Components and Properties of Radial Chinese Fir

The variability of main chemical composition of radial Chinese fir was studied. Analysis of variance showed that variance was significant, especially for holocellulose and α-celluloSe; the hblocellulose content in heart wood was lower than that in sapwood; the lignin content decreased from Position t to Position 3, but increased gradually from Position 4 to Position 8; the a ~ cellulose content in heart wood was lower than that in sapwood; and the relative crystallinity was 59.97% in Position 1, 60i80% in Position 2, and about 42% in others.     

Study on biological and ecological characteristics of lps subelongatue Motsch

IntroductionIpsSubeiongatusMotschulskydistributesinKorea,Japan.someareasofEurope,andaIlChina.ItisoneofmaJorborerpestsofLarchplantationsinChinaandcausesseriousdamages.Since198os,domes-ticentomoIogistshavemadeagreatmanystudiesonlifehistory,occurringlawsandcontroImethodsofthlspestandalsogainedremarkabIeadvanceinmanagementandcontrolThispestisunlikeIytobefoundbeforerampantoccurrenceduetothecompIi-catednessofoccurringcausesanditshiddenlifeandrepaidreproduction.Rampantoccurrencenotonlybringsab…     

Study Tour on Community Forestry and Agroforestry Approaches in China

ＳｔｕｄｙＴｏｕｒｏｎＣｏｍｍｕｎｉｔｙＦｏｒｅｓｔｒｙａｎｄＡｇｒｏｆｏｒｅｓｔｒｙＡｐｐｒｏａｃｈｅｓｉｎＣｈｉｎａ（Ｓｅｐｔ．１６－２９，１９９６）Ｔｈｅｓｔｕｄｙｔｏｕｒｗｉｌｌｐｒｏｖｉｄｅ４ｄｉｆｆｅｒｅｎｔｍｏｄｅｌｓｏｆｓｏｃｉａｌ／...     

Torrent Classification and Hazard Zone Mapping Information System on GIS

以中文Ｗｉｎｄｏｗｓ３．１为系统运行环境，以ＷＩＮＧＩＳ为基础，用ＭｉｃｒｏｓｏｆｔＶｉｓｕａｌＢａｓｉｃ４０作为开发工具，建立了荒溪分类和危险区制图模型及其信息系统．该系统由文件管理子系统、属性数据管理子系统、图形数据管理子系统、应用模型子系统等构成．应用结果验证了系统模型的各项功能，表明系统设计合理，运行稳定、安全．     

Discussion on Status and Functions of China’s Forestry

In recent years, the quantity and quality of global forest resources are declining continually. Contrarily, the both in China are increasing, which is deeply related to the sustainable forest management and eco-system management in China. With the trend that world community knows more about the important role of forest, more and more functions of forest are recognized. The impact and functions of China’s forestry deserve more concern. Based on some experiences in the field of forestry research, the authors introduced and analyzed the key role of China’s forestry for the sustainable development, and explained the functions of China’s forestry, such as ensuring ecological safety, addressing climate change, improving economic development, promoting social harmony and prospering ecological culture.     

Application and Research Development of Ectomycorrhizae on Forest Disease Resistance

1 INTRODUCTIONEctomycorrhizae is a mutual symbiotic associationof ectomycorrhizal fungi and tender nutritive roots ofplants. It is universal in nature. It has an active effecton the growth and the establishment of forestecosystem and especially is crucial to the survival andgrowth of trees planted in adverse environments suchas that of soil drought, salinity and pH extremes. Mostof the ECM plants are arbors and shrubs, such asPinaceae, Cupressaceae, Fagaceae, Betulaceae,Salicaceae, Ul…