Scientia Silvae Sinicae, sponsored by the Chinese Society of Forestry, is an acadimic periodical. The number of papers published in this periodical from 1955 to 1994 has reached up to 1970, including 30 volumes 134 issues; with about 3700 persons (times) of writers being involved. About 840 papers were quoted in Forest Research, Journal of Northeast Forestry University, Journal of Beijing Forestry University, Journal of Nanjing Forestry University and Scientia Silvae Sinicae itself from 1988 to 1994; 339 papers were gathered by Chinese Forestry Abstracts from 1988 to 1991, the rate of gathering was 92.37%. Therefore, among the forest academic periodicals throughout China, Scientia Silvae Sinicae is the only one sellected by Chinese Academic Periodical Abstracts. According to the incomplete statistics, about 91.55% and 52.82% of the papers were the major projects and won the highest prizes at national, provincial and ministry levels. About 200 copies are distributed over 33 countries and regions of the world by subscriptions and exchanges. The world famous periodical Chinese Science Abstracts、 CAB and AGRIS have been successively gathering the English abstracts of Scientia Silvae Sivicae now, Scientia Silvae Sinicae has won several important prizes bestowed by the China Association for Science and Technology, the State Science and Technology Commission and the Chinese Society of Forestry.

A special computer program COMPLEX was constructed to determine the climatic parameters for the distribution region of Pinus tabulaeformis based on the research on the distribution rules of the tree species. Correlation models were constructed. The central region, which is the most suitable distribution region, and potential distribution region of the species under current climatic conditions were mapped using a Geographic Information System IDRISI. According to the averaged predictions by 7 GCMS for 2030, a projection was made for the future distribution of the pine. The results show that the potential distribution area of Pinus tabulaeformis will have a small northward shift indistinctively. The east part of the northern boundary will move northwards by 1. 4°, while the southern boundary will move about 0.2° in latitude. The east and west edges will both move towards the distribution center.The potential distribution region will shrink by 9.4% compared with the current area.The species will disappear mainly in the area with lower altitudes from 180 to 1200 m above the sea level. The central distribution area will reduce by 7%, and the reduction mainly happen at the southern boundary making the continuous distribution pattern discontinuous.

Based on the data obtained by single watershed experiment, the changes in streamflow by forest fire were studied. The results showed the forest fire in Daxinganling in 1987 resulted in the increase of annual runoff obviously in the initial stage, the runoff of melting snow in May tended to reduce. After forest fire, the ability to regulate the water circulation of forest was reduced, and the changes in streamflow depended on the precipitation even more.

The study of downiness of Hippophae rhamnoides L. subsp. sinensis Rousi is intended to clarify the chaos of definitions of different downiness, approachs the morphology and evolutionary relationships among downiness groups which provides a reasonable basis for the toxonamy, ecology and system evolution of Hippophae. Observed under light microscope and scaning electron microscopes, two types and six groups of downiness of Hippophae rhamnoides subsp. sinensis are indentified. The first type is spiral downiness, including spiral stellate, spiral stellate-peltate and spiral peltate downiness groups; The second non-spiral downiness, including stellate, stellate-peltate and peltate downiness groups. In systematic development, stellate peltate downiness, derived from stellate downiness, developsinto peltate downiness, and spiral downiness are derived from non-spiral downiness. Therefore, stellate and spiral stellate downiness are primitive character type; stellatepeltate and spiral stellatepeltate downiness are derived type; peltate and spiral peltate downiness are evolutionary type. In ontogeny, stellate and spiral stellate downiness generate first, stellate-peltate and spird stellate and spiral stellate downiness second, and then peltate and piral peltate downiness. The main function of the downiness of Hippophae mainly is to protect the buds overwintering.

Seeding physiology, viability and survival after cold storage were studied on Pinus tabulaeformis Carr., Platycladus orientalist (Linn.) Franco.When tree seedlings are held in cold, dark storage for prolonged periods of time, they are separated from the sources of environmental energy and information they need to develop in synchrony with the changing seasons. This affects many important physiological processes and variables. The change paterns of fungi infestation, chlorophyll contens, carbohydrate reserves, mineral nutrients, water potentials, RGP, DBB and electrolyte leakage of roots of cold stored Platycladus and Pinus tabulaeformis Carr. seedlings are investigated. The electrolyte leakage from fine roots is a very good indicator of stored seedlings viability. Pinus tabulaeformis Carr. seedlings require 35-80 days below 5℃ to overcome dormancy, whereas Platucladus seedlings have no such requirement.

A study on Euzophera batangensis Caradja was conducted in Fujiau province from 1989-1993. Euzophera batangensis Caradja is one of the primary pests damaging stem of Casuarina shelterbelt along the sea shore. The growth and resistance performance of 51 different geographical provenances of Casuarina spp. intraduced in 1987 and 1989 were investigated. The varianceanalysis showed that the ability of C₃₈, C₃₉, C₄₄, to resist the pest was quite significant and they were the most resistant provenances. More than ten species of natural enemies of the borer were collected. If the crown density is over 0.3 or the age of stand is over 2 years, the tree could de hardly damaged. The comparison of infectivety of 8 steinernematid Steinernema feltiae Agriotos was the best one. Putting the nematode to water inthe ratio of 200 nematode juveniles to one ml of water and spraying the lipuid to the damaged sites of the tress in forest, a mortality of 72.0% could be obtained. The best way to use Beauveria bassiana to control the pest was to spray the mixture of Beauveria, diesel oil and water, the motality was from 86.1% to 100%.

Based on the data obtained from September 1986 to August 1988, it was found that the most bird abundance (47 species) was in spring and the least (31 species) in autumn, and that the bird abundance in winter was 35 and in summer 36 species. There was the most resident bird species (67.7%) in autumn and the most migratory bird species (57.4%) in spring. The average densities in winter, spring, summer, and autumn, were 56.87, 56.81, 47.25 and 49.35 individuals per 10 hm² respectively. The difference of average densities among seasons was not significant. The higher average density of migrant birds, 43.10 individuals per 10 hm², was found in winter, then in spring and in autumn, the lower, 5.49 individuals per 10 hm² in summer. The difference of the migratory birds' densities between winter and summer was very significant. The average densities of the resident birds in one season were always higher than those of the migratory birds in the same and other seasons (F=8.727, P < 0.05). The difference of bird species diversity among seasons was not significant according to the analysis of variance.

In this paper, seventeen species of hardwood were chosen in the variation range of 100-1300kg/m³ wood density. The large Transverse compression deformation test and the collection of quantitative data were conducted under six kinds typical conditions of wood compression. (The conditions are the combination of three kinds of conditions which are airdried. 20℃, saturated water. 20℃ and saturated water. 100℃ with the restricting conditions.)On the basis of data analysis, the formulas which express quantitatively the relationship between stress and strain and stain were founded as following: In the formulas above, E is elastic modulus in transverse direction; σ_y is yield stress; ε_y is yield strain; ε_d is a measure of the strain when all of the pore space in wood is squeezed out. C is the armature of increasing speed of stress when strain above the yield point; ρ and ρ_s reefer to density of wood and material density of the cell wall respectively. K is a constant that depend on the factors such as the restricting conditions of compressive test, 0≤K≤1.The formulas above is adaptable to the tree species and the compressive conditions under the test conditions in this paper. Moreover, the results of calculation were very concordant with the data of experiment.

This paper puts forward a new mothod of balancing the big reciprocating inertia force of gang saw with the altering angular velocity of the shock attenuation device. The study and calculation indicate: the method can balance the reciprecating force by 99%; decrease the maximum reciprocating inertia force by 268 times and by 90 times over the present balancing method with counterbalance. Thus, the gang saw can elimlnate the vibration caused by impact, increase its tangential velocity and productivity of labor and the stability of the frame, This method provides the eneoretical base for ideal balanced gang saw.

Since 1982, the experiments of the rare-earth application to forestry have been carried out with both pot-planted seedlings and field trees. The results proved that the rare-earth can increase the seed germination rate, and growth of forest trees at nursery stock stage, and improve the quality of nursery stockes, e. g. Cunninghamia lanceolata (Lamb.) Hook, Schima superba Gardn, et champ, Castanea mollissima Blume, Paulownia sp., Populus sp.etc. It can also raise the seed yields and quality of Pinus elliottii Engelm and Cunninghamia lanceolata in a seed orchard. And there are obvious effects on the fruit set percentage and yields, as well as improving the quality of fruits for some dry or fresh fruit tree species, such as Juglant regia L., Ziayphus jujuba Mill, Castanea mollissima, Maius pumila Mill, Pyrus bretschmeideri Rehd, Crataegus pinnstifida Bge, Diospyros kaki L., Prunus armeniaca L., and so on. The studies on physiological effects of it in forest tree species during its nursery stock stage, and in economic forest tree species during its flowering and fruiting period indicate that it can promot chlorophyll formation and mineral element absorption by roots, increase photosynthetic intensity and dry matter accumulation, as well influence the contents of some organic acids, protein, fat, sugar, and Vc etc in the fruits and seeds. Now the technique for the rare-earth application to forestry have been used in production practice as a result of studing it for many years.

Urban forestry, developed from the fusion of forestry and landscape architecture, is an industry of setting up and managing urban forest ecosystem, which builds, manages and utilizes the biocenose—mainly the trees, and the facilities in cities. Urban forestry ecosystem is a subsystem under the urban compound ecosystem, which broadly participates in the use of substance and energy of the urban compound ecosystem, the coordinative development of society and nature, and the self-balanceing of the system.Urban foresty is a science of studying urban forestry ecosystem, construction, management and utilization of urban forest. The tasks of this science are those of making plannes, designs for urban forestry, studying utilization and effects of urban forestry, providing relative basis for legislation, constructing kinds of forest types, plant communities and landscapes, and selecting and producing plant materials.

The breast height form factor (f_1.3) is a subset on a series of the normal form factor (f_n), which has the specialities of f_n. Based on the mathematic derivation and calculation of a felled tree, the relationships between the specialities of f_n.and relative height (n), form index (r), and between the specialities of f_1.3 and total height (h), r are as follows: 1. To the same r, f_n, increases with increasing n, however f_1.3 decreases as h rises. 2. When 0.03≤n≤0.22 for f_n to the same n, 5.87≤h≤43.33m for f_1.3 to the same h, the larger the value of f_n and f_1.3, is the plumper the stem form is so that the stem form may be reflected. f_n and f_1.3 are used as conversion factors for volume; When 0.22 < n≤0.37 the same n for f_n, 3.51≤h < 5.87m, the same h for f_1.3 only apply to conversion factors for volume; When 0.37 < n < 1 for f_n, or 1.3 < h < 3.51m for f_1.3, a fraction of f_n or f_1.3 (it is various in different tree species) is used as a conversion factor for volume, but most of them are not ideal for applying to the reflection of stem form or conversion factors for volume.

This paper compares the integrated rotation of goal with that of begin and end by analysing relative factors. It advances also three design models used for forest resource in future and examines in examples.