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Studies on the Characteristics of Foliar Surfaces of Hippophae and Related Taxonomy

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北京林业大学学报 1992年第S2期14卷 64-69页

作者： Zhang ZhixiangForest Resources college, Beijing forestry University

Trichome forms and stomatal distribution and types were undertaken. The results show that trichome forms are stellate, peltate and stellate-peltate. There is a difference in the position of stomata among the taxa of Hippophae. H. thibetana, H. salici-folia. H. gyantsensis, H. neurocarpa and H. rhamnoides ssp. turkestanica have stomata on both foliar surfaces, while other subspecies have stomata only on the lower surface. Stomata are of the Actinocytic type.

关键词： Hippophae. trichome stomata epidermis

Choice of Species in China's Plantation forestry

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北京林业大学学报 1992年第S2期14卷 15-24页

作者： Shen GuofangForest Resources college, Beijing forestry University

This paper reviews the new developments in the choice of tree species for China’s plantation forestry in relation to forest regionalization and site classification. After a brief discussion on the fundamental principles of choosing species,it gives the statistical data of the species composition of established forest plantations and recommendation for suitable tree species for plantations in some important forestry regions. Results of studies in 3 different cases have been given to illustrate the research approach in choice of tree species in accordance with the planting sites.

关键词： choice of species forest regionalization site classification

The Research and Control of Woodboring Insects in China

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北京林业大学学报 1993年第S3期 53-60页

作者： Wang Ximeng Department of forestry,Ningxia Agricultural college Zhang Zhen Institute of forestry,Chinese Academy of forestry,Beijing

Characteristics and occurence of woodboring insectsSome woodboring insects complete their entire life cycle in tree trunks (Scolytidae),oth-ers spend most of their life cycle in tree trunks ,such as round- headed borers(Cerambicidae) ,and flat-headed borers (Buprestidae),clearwing moth (Sesiidae) and car-penterworms (Cossidae). They shelter in trees and feed on the phloem and xylem, causingthousands of holes and wounds on the trees that result in the death of the trees. Compared to

关键词： In The Research and Control of Woodboring Insects in China

A Brief Account on Biological Control of Forest Insect Pests in China

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北京林业大学学报 1993年第S3期 45-52页

作者： Wang Ximeng Department of forestry,Ningxia Agricultural college Zhang Zhen Institute of forestry,Chinese Academy of forestry,Beijing

In China ,Forest Entomology separated from Agricultural Entomology after the foundingof People’s Republic. Biological control measures of forest insect pests have gradually devel-oped in recent ***, biological control was first applied in China. One thousand six hundredyears ago, there was a record of the application of the red tree ant(Oecophylla smaragdina)forthe control of orange pests in orchards. Two thousand four hundred years ago, Beauveria was

关键词： A Brief Account on Biological Control of Forest Insect Pests in China

Wild Alpine Flower Germplasm Resources of the Changbai Mountain Nature Reserve

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北京林业大学学报 1993年第S3期 83-89页

作者： Su Xuehen college of Landscape Architecture,Beijing forestry University

The nature reserve of Changbai Mountain was established in 1960. It is known for its richplant germplasm resources , among them the wild alpine flowers are most interesting germplasm resources inthis rich alpine vegetation pool. From June to July,Rhododendron chrgsanthum Pull,*** Maxim,ft. confertissimum Nakai, Phyllodoce caerule ( L. ) Babingt, Vaccinium vitisidaea L. , Dryas daerulea (L. )Babingt,Polygonum laxmanni Lepech,P. viviparum L. , P. ochotense V. Peter. ex Kom. grow profusely. Becauseof the special natural environment of Changbai Mountain, many endemic wild alpine flowers grow naturally,such as Minmartia macrocarpa (Parsh)Osterf,Papaver psendoradcatum Kitag, Geranium paishanense Y. ***, Gentiana james Hemsl, Oxytropis anertii Nakai and Hedysarum ussuriense. I. Schischk. All of thesespecies could be used in rock gardens.

关键词： wild alpine flower plant germplasm resource natural reserve

Root Growth Potential and Energy Sources for New Root Growth of Three Conifer Species in Northern China

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北京林业大学学报 1993年第S3期 10-22页

作者： Liu Yong Forest Resources college,Beijing forestry University

Seedlings of Pinus sylvestris var. mongolica, Larix principis—rupprechtii and Platycladus orientaliswere lifted from the nursery in March and transplanted to favorable growing conditions in a controlledenvironment chamber. The test of RGP showed that Platycladus orientalis seedlings had the greatest RGP amongthe three species, any one of the four parameters as TNR, TNR>1, TLR>1 and SAI could representthe RGP of Platycladus orientalis. However, at least two parameters (TNR and any one of TNR>1,TLR>1, SAI)must be used to represent the RGP of Larix principis—rupprechtii and Pinus sylvestris *** seedlings due to the weak correlation between root initiation and root elongation for the twospecies. The results of the RGP test and carbohydrate analysis for different treatments demonstrated thatcurrent photosynthate is needed for new root growth in Pinus sylvestris var. mongolica seedlings, whereasstored-carbohydrates provided the energy source for new root initiation. Current photosynthate is also neededfor root elongation in Larix principis — rupprechtii seedlings; New root growth of Platycladus orientalisseedlings is primarily caused by current photosynthate, but some reserve materials may be utilized at thesame time if photosynthesis is inadequate to meet growth demands.

关键词： root growth potential(RGP) current photosynthate stored carbohydrates

Studies on Topophysis in Seedlings and Suckers of Populus tomentosa Using Tissue Culture and Cutting

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北京林业大学学报 1993年第S3期 23-30页

作者： Fu Jianming Forest Resources college,Beijing forestry University

Different segments of seedings and suckers of Populus tomentosa were propagated using methodsof tissue culture and cuttings. Vegetative propagation abilities of different segments are compared . Thepurposes of this research are to determine whether topophysis exists in seedlings and suckers of Populus tomentosa,and to probe the change in patterns of topophysis. The results show that the callus weights,the differentiationrates of shoots and rooting rates which are major characteristics of expressing propagation abilitiesin tissue culture are apparently different and have an increasing trend with the decrease of the positionsfrom which the explants are taken. The rooting rates of cuttings have the same trend. These results demonstratethat there is topophysis in the seedlings and suckers and that topophysis patterns are the same as thoseof mature trees.

关键词： tissue culture seedling sucker topophysis Populus tomentosa

A Study on Mechanisms of Drought Tolerance in Tree Species

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北京林业大学学报 1993年第S3期 1-9页

作者： Li Jiyue Forest Resources college,Beijing forestry University

According to ways of responding to drought stress,two primary types of drought resistance intree species have been identified: (1)drought escape; (2)drought tolerance (including dehydration postponementwith high tissu... 详细信息

关键词： drought drought tolerance water stress water potential turgor pressure osmotic adjustment

STUDY ON THE NETWORK OF FOREST BURNING LINKS

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Journal of Northeast forestry University 1991年第2期2卷 1-6页

作者： Zheng Huanneng Hu Haiqing Northeast forestry University Wang Dexiang Northwest forestry college, Xi’an 1. Northeast forestry University China 2. Northwest forestry college Xi’an

Based on the research of the Forest Burning Links published in the Journal of Northeast forestry University in 1987, this paper continues to study the theory of forest burning. Fire behavior has been divided into two important series in this paper. One is fire occurrence and spread, and the other is burning intensity. The first series has been divided into three grades as A: to burn difficulty and spread slowly; B: to burn possibly and spread little fast; and C: to burn easily and spread fast. The second series has been divided into four grades as Ⅰ: light burning; Ⅱ: medium burning; Ⅲ: intense burning; and Ⅳ: severe burning. The first series can be put as ordinate, and the second series can be put as abscissa. Then the network of 12 forest burning links can be formed. In the network, the relationship, the law of distribution and the variation of different forest burning links can be shown clearly. The studies of the distribution of fuel types, topography, site and fire kinds in the network can provide the basic theory for fire management.

关键词： Forest burning link Fire management