The method of simulating diagnosis was derived for the research of foliar optimum nutrient status from the sample plots which were the treatments of experiment on amelioration and increasing fertility with Ⅰ-69 poplar (Populus deltorides Bartr. Cv. "Lux") on Sajong black soil. By canonical correlation analysis, sampling time was selected, and foliar mutriment elements closely related to forest tree growth were determined.Parabolic function was taken as the diagnosis function of optimum nutrient status in foliar. While selecting the variable of diagnosis function,content of foliar nutrient and the proportion of nutrients were considered. It was concluded that optimum foliar nutrient status for Ⅰ-69 poplar was as follows: The leaf content of P₂O₅ was 0.55—0.75% in July in the first year after plantation; N was 3.20—4.20% in the next year; N was 3.00—3;70% in May in the third year; N/K was 1.00—1.60 in the fourth year.

The changes in contents of Vitamin C, Vpp, V_E in fruits of seabuckthon (Hippophae rhmnoides L. subsp, sinensis Rousi and H. thibetana Schlechted) which are naturally distributed in Wushaoling area have been investigated and analyzed systematically during fruit growing and ripening period.The main results are as follows.Ascorbic acid (V_C) mainly exists in fruit flesh, which increases with fruit development, and reaches maximum value at fruit color change phase (about 107—110 days after anthesis)and thn drops rapidly. While it in fruit flesh diminishes it contained in seeds increases.The Vitamin pp (V_(PP)) contact is very high in fruit flesh at the early stage of fruit development, and then gets lower gradually. It increases again during the ripening period. These show the same growth and decline pattern with the changes in respiratory rate.The Vitamin E (V_E) exists mainly in seeds, which has on upword tendeney with fruit growth. It reaches its first peak value at the phase of seed color change, then drops to its second peak value when fruits are ripe.The V_E. Content in H. thibetana is higher than that in H. sinensis.The possible physiological functious of these vitamins are also discussed in this paper.

The effect of tree crown disposition on the vertical distribution of annual increment in the main stem of Populus deltoides Bartr. cv. "Lux"ex. 1-69/55 was studied by measurement at fixed position in 1985-1986. The tend of distribution of annual increment inside plantation was different from outside. The increment of main stem under branches of the latter was more than the former. The maximum increment of stem diameter was at bottom, diminished up to branch height, then increased to crown. With increase of pruning height, the volume increment of crown stem became greater than the below stem. Cross-section area of lateral branch increased 1cm², the difference between upper and below section areas at the positions of growing branch was about 0.7cm². Pruning is important for reguiation of increment in main stem.

According to the principle that contents of water and heat are the two main factors for determining the geographical distributions of tree species, moisture-therm indices have been developed with drougt index and growing degree days, for the 8 species (Pinus koraiensis, Fraxinus mandshurica, Tilia amurensis, Qurcus mongolica, Acer mono, Ulmus japonica, Betula platyphylla, and Populus davidiana) in the Korean pine/deciduous mixed forests. By assuming that tree growth under optimum conditions is proportional to its leaf biomass and is inversely proportional to its size, the optimum growth model has been derived for the 8 species. With combination of the index and growth model,the optimum growth processes of trees grown under different conditions of moisture and heat has been simulated, and the growth features of different species and the same species under different moisture and heat conditions have been revealed. These results can be used for classifing quality of geographical distributions of tree species and evaluating a stand growth.

Both mycelia and sclerotia of Rhizotonia solani were parasitized by Gliocladium virens (GVP). The parasitized sclerotia were incapable of germination. The metabolites produced by the mycoparasite either inhibited or killed the host fungus. Scanning electron microscopy showed that the mycoparasite tightly coiled around the host fungus, formed appressorium-like structures on the host fungus and presumably achieved its infection by active penetration.

Four new species of the genus Coraebus are described and four new records of the same genus from China are reported in this paper. All the type specimens are desposited in the Department of Plant Protection, Southwestern Agricultural University, Chongqing, China. Coraebus simplex sp. nov. (fig. 1 )Body elongate, robust, entirely dark blue with somewhat green ring. Head very short, sparsely and coarsely scattered with irregular punctures, frons deeply and longicudinally depressed at middle. Pronotum tranverse, disk very strongly convex at middle of anterior margin, prehumeral carina present, but very short, Elytra elongate, about 2.6 times as long as wide at base, apex separately rounded, surface with dense, irregular punctures, but without conspicuous ornament of pubescent hairs.Lenth: 10mm. Width: 3.5mm.Holotype: ♀, Helongtan, Kunming, Yunnan Province, 1986-Ⅵ-10by Peng Zhong-liang.Most species of this genus possess bands or spots of pubescent hairs, this species is one of the several species without pubescent ornament and it can be distinquished by the different colour and the form of elytral apex from others.whitish pubscent hairs, on basal half of elytra with some other irregular and fragmental spots or bands of pubscences of the same colour.Lenth: 9mm. width. 3.5-4mm.Holotype: ♀, Helongtan, Kunming, Yunnan Province, 1986-V-18 by Peng Zhong liang. Coraebus yanshangensis sp. nov. (fig. 4 )An elongate and subcylindrical species, body entirely dark blue with somewhat green lustre. Head very short with sparse but coarse punctures. Pronotum tranverse, with dense and irregular punctures but without conspicuos ornament of pubescence, prehumera carina absent. Scutellum tranverse, but sharply pointed apically Elytra elongate, elatral apex separately rounded and finely denticuated, surface ornament of pubescence as follow: at posterior half of elytra with two tranverse bands of white hairs, first one at posterior 3/4 of elytra, slightly sinuate, the second near apex more straight, in addition, at middle of elytra towards outer margin with a very short pubescent band, at humeral depression and along sutural margin with some sparse pubescent hairs.Lenth: 10mm. Width: 3.5mm.Holotype: ♀,Yanshan,sichuan Province,1979-V-28,by Ma Wang quan.This new species is allied to C. annamensis of Indochina, distinguished by the presence of a pubescent spot in the middle of elytra and without prehumeralcarina, while C. annamensis with prehumeral carina but without pubescent spot in the middle of elytra Coraeous denticollis Saunders, 1886, (New record to Chinese,fauna) Specimen examined. 2♀,Jingdong, Yunnan Province, 1956-V-23 by Jiang Shan Coraebus mianningensis sp, nov. (fig, 2 ) Body broad, head and pronotum aeneous, basal half of elytra aIso aeneous with somewhat sparse white pubescent hairs along sutural and latral margins,posterior half of elytra black or dark blue with four tranverse bands of pubescent hairs, the first one at posterior 3/5 of elytra, rather sinuate, the second one just behind the first, more straight, but very wide towards sutural margins, the other two near apex, more arcuate, the apex is separat ately rounded and finely denticuate, surface with dense and irregular punctures. Pronotum without any conspicuous pubescent hairs but with prehumeral carina, which extending from base to middle of pronotum. Scutellum tranverse but sharply pointed apically.Lenth: 12mm. width: 4mm.Holotype: ♀, Mianning, Sichuan Province, 1980-Ⅵ-3. by Fang Hou quan.This new species is distinguished from any other species of the genus by the ornament of white pubscent hairs on elytra. Coraebus obscurus sp. nov. (fig. 3)An elongate and subflattened species, body entirely dark black with somewhate violet tint on head,pronotum and margins of elytra. Head very short, with dense punctures, pronotum tranverse, disk strongly convex anterior medially, suface densely but unevenly covered with yellow-whitish pubescent hairs, but without prehumeral carina. Elytra elongate, about 2.5 times as long as wide at base, elytral apex subtrancated, with two short and obtuse lateral spines respectively, surface with two parallel bands of yellow-whitish pubescent hairs near apex, and just behind middle with a very narrow incured thread-like band of yellowDistribution: China(Yunnan), Indochina. Coraebus grafi Obenberger, 1934, (New record to Chinese fauna)Specimen examined: 1♀, Beipei, Sichuan Province, 1985-Ⅷ-17 by Pang Zhong liangDistribution: China(Sichuan), Indochina. Coraebus salvazai Bourgoin, 1922, (New record to Chinese fauna)Specimens examined: 1♀, Guiyang, Guizhou Province, 1980-Ⅵ-18 by Peng Zhong liang.Distributions China (Guizhou) , Indochina. Coraebus violaceipenis Saunders, 1866, (New record to Chinese faSpecimens examined.. 1♀, Huaxi, Guizhou Province, 1980-Ⅵ-18 by Chi Fu xin.Distributions China (Guizhou) , Indochina.

According to the investigation of main forest factors on 26 typical plots and the observation of climatic factors and ascospores dispersion way lasting 2—3years,the results analysed with different mathematical methods show that the disease incidence of Korean pine needle cast decreases along with higher elevation and elder forest age, and increases with thicker forest density.By means of the analysis of soil nutrition and pH value,it is indicated that the disease occurrence is not significantly related with nutrition of forest land. The dispersing amount of ascospores is controlled by climatic factors. ≤23℃ daily mean temperature, ≤90% daily mean relative humidity, and≤24 mb daily absolute humidity are the optimum conditions of ascospores dispersion. When the daily precipitation is≤0.5mm, the ascospores dispersion is restrained. It is suggested that controlling this disease should be put stress on the middle and young forest under 10m.

The value of tlchnical parameters of side boom in the rivers flowing at a high speed is determined by boom-model hydraulic test. The limit value of the angle between the axis of the lead boom with a water pressure-bearing splash board and current has been determined, and the relation between the value of the vertical force exerted on the lead boom with a water pressure-bearing splash board and flowing speed has been set up. Thus, the technical data of separating water width of wing-typed boom with the changing of flowing speed effectual guided length and resistance have been obtained.

In order to study random vibration and running smoothness of logging trailer-truch this paper puts forward a kind of computer simulating method for calculating the random vibrations. Based on five inputs and ten degrees of freedom, a mathematical model of tree-lehgth logging trailertruck is set up. Simulating calculations about a tree-length logging trailer-truck, model LT-110+GT15C, are carried out with the IBM computer. The results of field test correspond with that of theoretical calculations. Therefore, the mathematical model advanced in this paper can be used to predict the running smoothness and optimize structural parameters of tree-length logging trailer-truck as well.

Firstly,this paper reviews the main points of recent academic arguments on the forest site classification and evaluation in China. Secondly,the main principles and methods related to forest site classification and evaluation,which could be considened in China are suggested. Meanwhile, the importance of topography and soil in a certain area in forest site classification and evaluation have been expounded in this paper emphatically.

The full understanding of technical and economical level of wood industry of our country is one of the essential requirements in working out the medium and long-term plans and strategy for developing science and technology of the industry. In this study the method of establishing targets system for comprehensive appraising technical and economical level and "Scientific and technical measurement model" is firstly used, i. e. a quantitative method is used to reflect the present level of China's wood industry and it's change in recent years. Besides, the author concretely analyses all targets on the basis of the data obtained and puts forward a proposal for increasing the total technical and economical level of China's wood industry in the future.

The authors research the different rooting capacity of shoot cuttings of some cypress tree species, including Sabina vulgaris Ant., Platycladus orientalis(L.)Franco cr.'Sieboldii' ,P.orientalis(L.)Franco cv.'Semperaurescens' ,S.chinensis(L.) Ant., S.chinensis(L.) Ant. cv. 'Kaizuca',and Juniperus rigida Sieb. Et Zucc, and emphatically in quire into the physiological bases causing such different rooting capacity. According to the results, those cypress tree species can be divided into three types: easy rooting, more difficult and most difficult. The effects of NAA or IBA supplied in stimulating rooting of shoot cuttings are very complicated,as the differences are not only from tree species but also from different cuttings. Further the authors point out that these different effects are related to endogenous IAA/ABA ratio in cuttings. The higher IAA/IBA ratio may be the conditions for inducing adventitious roots. NAA application to cuttings can induce ETH production,whose level has correlations to NAA treatment and rooting capacity of tree species.

The Clethrionomys rufocans is an important rodent pest for young forest. This paper deals with the control measure during 1982-1987 in the Forest Bureau of Dailing. On the basis of habit that it's fond of eating tender oark, according to its regular dispersion, some branches from the residue of tending were thrown to substitute the food in young forest. Field experiment showed that this control measure was effective, and reduced the number of the voles, which protected the natural enemy, also saved the rodenticide cost.

A new angle-count method for estimating the increment of stand growing stock has been proposed based on the angle subtended by the sample tree in this paper. As compared with other angle-count method, it has several advantages, for instance, smaller variance, higher relative efficiency, and convenient for continuous checks etc. The result tested by the data of continuous checks and measurements in Guangxi CFI has proved the advantages of the theoretical analysis of this method.

In this paper, the finite element method (FEM) is used to analyse the strengfh of case furniture. The case body is made of particleboard and the back is made of plywood or fiberboard. These boards belong to viscoelastic behaviour materials, but they can be considered as linear elastic behaviour materials within a certain area and dispersed and analysed by elastic plate elements. The corner joint of case furniture is a key problem during the calculation by FEM the small elements which located near corner joints are assumed to be semi-rigid elements. Then the fabricated modulus of elasticity of the semi-rigid elements are determined by individual corner joint experiments.In this experiment, four kinds of particleboard and two kinds of corner jiont forms were ussd to make up eleven cases. The displacement of some typical points under each load was measured by the Fturniture strength Test Mechine. After comparing the displacements of measurements with that of calculations, it was found that the errors were usually below 30%. Results of this study indicated that the deflection of case furniture could be calculated by using FEM, and proved that the program could be used for predicting case furniture deflection reliably.