Monocalyptus is a subgenus, the second largest in the genus Eucalyptus L'Hetitier, including 134 species and 9 subspecies. The species transfer of Monocalyptus is of great significance in ecophytogeography. A species elimination test was established in Yipinglang Forest Farm, Yunna Province, China with 11 species of Monocalyptus. 7-year results showed that E. regnans, E. obliqua, E. delegatensis, E. elata, E. fraxinoides, E. triflora, E. fastigata, E. dendromorpha and E. muelleriana were adapted to the local environments and very promising in growth rates in comparison with E. globulus planted at adjacent plots at the same time. A conclusion could be drawn from the trial that site selection would be essential for successfully planting Monocalyptus, the temperature regime be more critical for the species transfer of Monocalyptus than that of precipitation.

Based on the fixed field monitoring data of soil water content during the growing season in three different plantations(Populus hopeiensis, Populus sinmnii, and Caragana korshinskii), by means of soil water characteristic curves the authors studied the soil water holding ability, the specific water capacity as well as soil available water of three plantations at different period of growing seamn in different precipitation year. The results were as follows:Of the P. Hopeiensis, P. Sinmnii, and C. Korshinskii plantations the soil water holding capacity was relatively lower. Among them the soil water holding capacity and the specific water capacity had the following order:P. Hopeiensis plantation. > P. Simonii plantation > C. Korshinskii plantation. Although the dynamics of SAW(soil available water)in a certain year was deternfined mainly by the amount and seasonal distribution of rainfall it was also influenced by the successive years of drought. Therefore when the precipitation during the growing season was 494.3mm(1992), 234.8mm(1993), 338.5mm(1994)and 651.6mm (1995), respectively, the SAW content had following order:1995 > 1992 > 1993 > 1994. There was little of SAW content during the early period of the growing season in 1992 and 1995, and it was even quite low during the whole growing season in 1993 and 1994.

Through determining the contents of secondary metabolites(active constituents)in Eucommia ulmoides Oliv.(Duzhong)leaves, it is found that secondary metabolites appear dynamic accumulation trend.Variance analysis of the contents of secondary metabolites is notable in different clones.The result illustrates that the inheritable gene is an important factor in regulating the formation of secondary metaboiltes.In the growth season of Duzhong leaves, the contents of chlorogenic acid and aucubin are highest in June and November.The content of geniposidic acid is the highest in June, too.The content of flavonoids, however, is the highest in May.The content of gutta-percha is the highest in May and June, then decreasing gradually.It seems that correlation exists between dynamic accumulation of secondary metabolites and tree growth rate.

On the basis of survey materials from 38 sample plots, the author regarded the basal area of breast height ratio of saplings and young trees under the mother trees as the transition probobility, predicated not only the composition of tree species on balance status, but also the dynamic process and trends of survived forest community in Daqinggou in longer periods and larger scales through the data comparison between present and 30 years ago, by means of the Markov succession model. The results show, if the environmental conditions keeping smoothly, the community which Quercus mongolica, Fraxinus mandshurica are main species are more stable, while the community which Ulmus macrocarpa is main species fluctuated greatly. The quantitative correlation of species composition in different communities in balance stutus will be changed variously.

The article is a part of the "research on productivity and ecological borderline effect of ecology economy system in Dayawan Bay, Guangdong Province, South of China". The typical sampling and transect methods are principally used for the community structure and quantitative characteristic of mangrove forest in Dayawan Bay. The quantitative parameters such as the diameter, height, growth rate, storage volume, growth volume, consumption volume and the primary productivity of the mangrove plant species are measured. This research work is an important foundation of studying ecological borderline effect of the special plant community at the border area between the land and the sea.

The genetic resource of Populus deltoides Bartr., a fast growing species of rich genetic variation, is poor in China and need to be introduced from foreign country. In 1980's 331 clones of Section Aigeiros consisting of 52 clones of P.deltoides, 56 clones of P.×euramericana and 6 clones of P.nigra were introduced from 17 foreign countries. In 1984 the first gene pool of Section Aigeiros in China was established in Changqing County, Shandong Province. The several characters in clones of Section Aigeiros had been measured and studied for ten years. The results showed that there were significant in phenology, growth, rooting, cold resistance, disease and pest resistance between different colnes, and the genetic variation was rich. The rules were as follows:(1)Growth showed significant negative correlation to the original latitude.(2)Cold resistance showed significant positive correlation to the original latitude.(3)Rooting ability tended to add little with the height of latitude.(4)Disease resistance showed slight significant positive correlation to the original latitude, as well as negative correlation to the original longitude.(5)Change of season showed significant correlation to growth of standing stock.(6)Cold resistance showed significant positive correlation to growth.(7)Disease resistance shows positive correlation to cold resistance.Basic wood properties such as wood basis density, fiber length, tree height, and DBH were also measued and analyzed. The results showed that a significant variance was observed in 4 traits among 46 clones and there was slight negative genetic correlation between the wood basic density and tree growth rate, as well as positive genetic correlation between the fiber length and tree growth rate. RAPD analysis was applied to the analysis of DNA polymorphism and genetic differentiation among the clones. The percent of polymorphism was up to 80%, which showed that genetic diversity of this gene pool was significant. The gene pool will provide rich breeding material for improvement of poplar in China.

The pollination experiments were carried out in Pinus tabulaeformis Carr. Seed orchard located at Lushi county in Henan province during 1993~1995, The pollination efficiencies of different pollination experiments were also analysed. The first pollen grain arriving at the integument arms was preferentially engulfed over pollen approaching later during female cone receptive period. The optimal time of pollination was the first 4 days after flowering. The controlled pollination carried out within 2~3 days after flowering gave the greatest efficiency with 54% of full seeds. The repeated pollination during receptive period could not significantly increase seed numbers over single pollination. The 45%~50% of full seeds in cone could be produced when 0.2~0.4 mL of pollen was applied to one pollination bag, and a markable decline in pollination efficiency be followed when less than 0.1 mL of pollen was applied. The mixtures of fresh pollen with dead pollen or talcum powder at the ratio of 1:1 could produce the same percentage of full seeds as pure fresh pollen applied. In addition, the pollination efficiencies of different treaments, the determination of weighted values for flowering synchronization indexes and changes of flowering synchronization indexes after weighting were preliminarily discussed.

Tree mortality model is an important part of tree growth model system. Logistic regression was used to model tree mortality of Larix based on the data from l31 diameter-class groups of l2 forest management inventory remeasured plots in Wangqing Forestry Bureau of Jilin Province. Independent variables are diameter class, relative diameter (RD), number of stems per hectare, basal area per hectare, quadratic mean diameter (DG), degree of closeness (P) and sum of squared diameter of larger trees than the predicting diameter class. An empirical equation including RD, P and DG was proposed by means of square correlation coefficient and coefficient of variation for all parameters. The equation is characterized by simple form, convenient measurement and calculation, without requiring stand age and site quality index, and good stability of the parameters. It may be used to predict mortality ratio of diameter class and mortality probability of individual tree for Larix.

An investigation on insect natural enemies of gypsy moth, Lymantria dispar L. (Lepidoptera:Lymantridae) was carried out in 1996 and 1997. Totally 23 species of the natural enemies were gotten, of which 17 species are parasitoids and 6 predators. Two egg parasitoid species made a parasitism of 5.2%~10.9% and Ooencyrtus kuvanae (Howard) (Hymenoptera: Encyrtidae) was the dominant species. The dominant larval parasitoid species were Meteorus pulchricornis, Glyptapanteles liparidis, Apanteles sp. (Hymenoptera:Braconidae), Phobocampe lymantriae, Casinaria nigripes (Hymenoptera: Ichneumonidae), The larval parasitoids could parasitize the pest with an average parasitism of 9.55% and kill them later. The pupal parasitoids had a parasitism of 19.08%, these contain the 5 larval pupal parasitoids of tachinidae (Diptera): Exorista rossica, E.japonica, parasetlgena silvestris, Compsilure concinnata, Palexorista laconspicua and the real pupal parasitoids: Coccygomimus disparis, Theronia atalantae gestator (Hymenoptera: Ichneumonidae), Brachymeria lasus (Hymenoptera: Chalcididae) and Tetrastichus sp. (Hymenoptera: Eulophidae). Altogether, about 30.1% of the gypsy moth individuals were killed by natural enemies from egg to pupal stage. These data showed that the natural enemies played an important role in controlling the population of gypsy moth.

The detecting results of the basic nutrient materials, the chemical substance content of phenolic type, etc.and the wood fibre morphology of 4 Casuarina species with different insect-resistant performances were reported, the relation between the chemical and morphological factors of Casuarina spp. and the harm of Anoplophora chinensis was analysed and the insect-resistant mechanism of Casuarina spp.was studied.The distribution difference of basic nutrient material content in the Casuarina barks was not notable whereas that in their xylems was obvious, i.e. their content reduced with their insect-resistant performance enhancement, which caused the wood internal environmental difference of different strains of Casuarina and formed the living environmental difference of A. chinensis, the bole-boring injurious insect.The soluble total carbohydrate content in the highly sensitive Strain C₂₃(2.80%) was obviously higher than that in the highly resistant Strain C₄₄(0.62%) and was 4.52 times as high as the latter.The free amino-acid content in the C₂₃(1.857g) was 1.94 times as high as that in the C₄₄(0.955g).Meanwhile by adopting the glucose solution and the clear water(for a contrast)respectively to soak Casuarina segments and imitating the burrows with the segments to inoculate A. chinensis larvae for a feeding experiment, it was also tested and verified that the enhancement of the glucose content was advantageous to the enhancement of the larva living rate, which illustrated that the chemical nutrient material content in the xylems was closely realted to the larval growth and development.The phenolic compound (such as catechol or caffeic acid) content in the highly resistant Strain C₄₄ was obviously higher than that in the other strains.The average wood fibre length of the C₄₄ was 0.77mm, its average fibre width was 12.07μm and its ratio of length to width was 63.6.Its wood fibre was the thickest and strongest in that of all the strains, which illustrated that its fibre tenacity was the strongest and its bending strength was the highest to cause A. chinensis to nibble difficultly and also illustrated that its wood fibre status tallied with its performance of both insect resistance and wind resistance.

This paper reports the following results of study on the integrated control of Moso bamboo foot rot caused by Arthrinium phaeospermum: (1)40% compound of seedvax and thiram and 70% thiophanate methyl WP were found to have very good fungistasis for this pathogen; (2) Cultivating and selecting big and strong bamboo shoots should make them rapid growth to 2m in height before the initial infection occuring, thus to avoid infection; (3)Peel off the basilar shealth of bamboo shoots could reduce the disease developing; (4)This technology of integrated control have been used to bamboo forest, the control efficiency got 92.46%.

By studying in detail in jujube forest, the behaviors of tending to sex pheromone on the adult Ancylis sativa Liu, the rhythm of trapping the males and the control of the pest by sex pheromone in jujube forest in a large acreage are understood. There are two trapping peaks: the first one is from 4:00 to 6:00, trapping rate is from 37% to 76%; the second one is from 18:00 to 22:00; trapping rate is 15% or so. Sex pheromone can not only affect the courting and copulation of the adult Ancylis sativa Liu, but also disturb its flying behaviors in the course of feeding dispersal and concealment. A large acreage pheromone trap experiment indicates that the fertilized eggs of the pest are reduced from 68.5% to 85.2%.

In this paper, the calling behaviour and the effects of environmental temperature and photoperiodic changes oncalling behaviour and sex pheromone release in Ancylis sativa Liu were investigated. The results showed that the females calling peak period of Ancylis sativa Liu was at 6.0~8.0 hours in scotophase. The higher the temperature was, the later females called, the shorter the calling behaviour lasted. The sex pheromone titre released by females at 31℃ or 16℃ was almost only 1/5~1/4 of that released by females at 21℃. Meanwhile, the E/Z was changed with the temperature, that is Z isomer increased while the temperature decreased from 31℃ to 16℃, as well as the C.V. was perfectly controlled under 10%. Virgin females shifted to continuous dark from 14L:10D as 2-day old adults showed similar temporal patterns of both calling and pheromone production to those of moths held continuously at 14L:10D. This result indicates that both events have a circadian periodicity. When moths were shifted to continuous light at day 2, calling became inactive and irregular, whereas pheromone titres were equal or higher than those of moths under 14L:10D.

A novel polymer composite material(SMA WPC) was made from graft polymerization reaction with ternary copolymerization monomers such as styrene, methyl methacrylate and acrylonitrile(SMA) soaking into cell wall and activated cellulose. It was found that, by relative physical mechanical, water absorption, anti-acidity performances detected, the hardness of the manufactured material is 20%~35% higher, as well as the compressive capability of that 35%~45% higher than that of plain timber, And the weigh loss rate of the said substance decreases by 22% with three-day soaking in 98% concentrated sulphuric acid, and water absorption drops by 50% with eight-day dipping in water. And also, the microscopic structure before and after plasticiting was observed by means of scanning electron microscope.

The concept of contributivity was put forward in this paper.It can be used to measure the contribution ratio of solid wood properties to LVL strength.The contributivity of 3 poplar clones from plantation was studied and the results shows that poplar with good solid wood properties or LVL with thick veneers gives high contributivity.The average contributivity of good poplar 69, poplar 72 and poor poplar 63 is 74.34%, 67.48%and 64.72%, respectively.When LVL is assembled with the veneers of 3.565mm, 2.614mm and 1.545mm in thickness, the average contributivity is 74.00%, 67.48%and 58.06%, respectively. In addition, the contributivity of shear strength, modulus of elasticity and toughness is approximated to 80%, which is higher than that of the other 3 properties.

Microwave plasma represents rather reactive media, so ablation will take place from wood surface in contact with microwave plasma. The ablation depends upon the energy of the reactive species, which in turn depend upon the nature of gas used and the treatment conditions. The ablation verity of wood (Chinese fir) sample in different treatment conditions, including location of sample in the reactor, time of treatment, electrical power used, gas pressure and different gas, including N₂, O₂ and air, has been investigated. The result shows that the location of sample to resonance cavity is the strongest affecting and factor followed by treating time, microwave energy level and gas pressure. Shorting distance of sample to resonance cavity, prolonging treatment time and increasing microwave energy level will result in ablation increasing. Oxygen is most effective on the action of ablation, followed by nitrogen and air.

The objective of mapping quantitative trait loci (QTLs) is to search for genes affecting quantitative traits with the aid of genetic linkage maps constructed from molecular markers. As a prerequisite for map-based cloning of important genes in biology, medicine and agriculture, the genetic mapping of QTLs has being brought about a revolutionary change in quantitative genetics. In the past decade, many statistical methods have been developed to estimate the effects of QTLs and locate their positions throughout the genome. Although these methods are based on well-defined pedigrees, such as F₂ and backcrosses, initiated with inbred lines, their theoretical framework can be developed to map QTLs in outbred forest trees. In this article, we review the principle of constructing genetic linkage maps and statistical basis for QTL mapping using the maps. Further directions for developing statistical mapping methods in forest trees are discussed.

Forest sustainable management is a strategic problem in the sustainable development of forestry. In this paper, the understand of human to forests in the course of history, and the development process of forest management were expounded. The concept and connotation of forest sustainable development were put forward, and then proceed to discuss the characteristics and indexes of forest sustainable management systematically.