Through field investigation of 53 gaps in some permanent plots of virgin tropical montane rain forest in Bawangling nature reserve of Hainan island, this paper deals with gap characteristics and their natural disturbance regimes in tropical montane rain forest of Hainan island. Gaps in the tropical montane rain forest are elliptic in horizontal forms, the ratio of long axis/short axis for each gap is about 1.4. The area percentage of expanded gap(EG) and canopy gap(CG) in the forest landscape is 53.52 % and 25.22 % respectively. The natural disturbance frequency for EG and CG is 1.34 %·a^-1 and 0.63 %·a^-1 respectively, the return interval of canopy gaps is about 160 a. The size of most EG in the tropical montane rain forest range from 30 m² through 500 m², averaged about 160 m². And the size of most CG in the forest range from 15 m² through 200 m², averaged about 80 m². Most gaps were formed 40 years ago, and most of which aged 10~30 a. Most gaps were made by 1~4gap makers, of which two gap maker gaps are the majority. The percentage of different dead gap makers are as follow:uprooting 16.88 %, standing die 14.29 %, breakage at trunk base 36.36 % and breakage on trunk 32.47 %. Most gaps were formed by some combination of gap makers of different die manners. Major gap makers are about 20 tree species, in which there are not only tree species in the first canopy layer, but also tree species in the second and third layers. Finally, based on the study of gap dynamics in the tropical montane rain forest in Hainan island, some suggestions were made about management in the tropical montane rain forest.

Through the studies on the shelterbelt management, sub-models of shelterbelt management including windbreak structure(optimal porosity β), relationship between porosity and protective benefit(β₀), coefficient of disaster(α), mature height(H_in) and effective interval of protection(D_ef)etc. were established successfully. Based on the sub-models, the model for continuative economic benefits of windbreak management(CEBWM) was obtained. The parameters and application examples of poplar shelterbelt were also given in this paper. The CEBWM can provide not only technologies for windbreak management, but also important parameters for windbreak planning and designing.

This study is on a timber harest decision problem, in which the timber price are varied as a self-correlation stochastic procedure. The uncertain factors in timber management and their effects are analyzed. An adaptive decision model for final harvest is established. The optimal decision policy which brings highest expected profit for harvest under a given decision period is obtained by the dynamic programming algorithm. The optimal policies under different risk and discount rate are also compared.

Mating systems of nine natural populations of the three Chinese Larix taxa (L. gmelinii(Rupr.) Rupr., L. principis-rupprechtii Mayr. and L. olgensis Henry) were scored using seven polymorphic loci of allozyme markers generated by six enzymes (PGI, MDH, 6PGD, AAT, PGM and SDH). It was observed that population Jiagedaqi of L. gmelinii in Inner Mongolia exhibited nearly total outcrossing (t_m=0.986±0.081). Two populations of L. principis-rupprechtii, Fengning in Hebei Province and Hunyuan in Shanxi Province, shared no significant difference from random outcrossing (t_m=0.847±0.427~0.792±0.169). However, mating system was variable among populations of L. olgensis. Two populations, Xiaobaihu in Heilongjiang Province and Changbai in Jilin Province, exhibited significant level of selfing (t_m≈0.705). One population, Dahailin in Heilongjiang Province, exhibited inbreeding in addition to selfing, with t_m bein.0.684±0.107, and the other three populations of L. olgensis, Baihe in Jilin Province, Baidaoshan and Dongfanghong in Heilongjiang Province, exhibited predominantly outcrossing, t_m=0.847±0.427~1.203±0.371. These results were comparable to those reported in other conifers including L. laricina [DuRoi] K. Koch and L. decidua Miller.

Through analysis on growth process of 29-year-old Chinese fir stand from seed in different rotation of continuous planting in Ancaoxia, Nanping, Fujian, the results showed that, before ten-year-old, the increment of tree height, D B H and volume for the first and the second rotations were close, after that, the growth of the second rotation declined rapidly, the mean individual volume of 29-year-old decreased by 41.46 percent compared with that of first rotation. The growth of tree height, D B H and volume of the third rotation were lesser than those of the second rotation at the beginning, but decline did not occur to a large range at last, the mean individual volume of 29-year-old trees reduced by 17.70 percent compared with that of the second rotation. The fewer of the planting, the earlier of the time reaching peak growth, the bigger of the peak value, and the longer of sustainable time over the fast-growing period.

There is an ever-increasing need for information relation to the spatial structure of uneven-aged mixed forests. Forest structure may be described on three levels:the level of species mingling, the level of tree size differentiation and the level of the tree point distribution. Suitable parameters are available for characterizing mingling and size differentiation, but the same cannot be said about the distribution of tree positions. The neighbourhood pattern, a new spatial parameter presented in this paper can be assessed with little effort in the field, without having to measure distances. It can be used to describe and reproduce stands with certain spatial characteristics(clumped, regular or random).

Three new species and two new formas from the nature reserve of Gaoligongshan are reported in this paper——Thamnocalamus tengchongensis Hsueh et Hui, Dendrocalamus pachycladus Hsueh et D. Z. Li, Yushania, Y. elevata f. pianmaensis Hsueh et R. Y. He, puberula Hsueh et Hui Y. Farcticaulis yi f. brevinoda Hsueh et H. R. Zhang.

Sixty-six rhizobial strains, isolated from root nodules of fifty-one species of woody legumes (five genera in subfamily Mimosoideae and eighteen genera in subfamily Papilionoideae) in East China, were studied by performing a fuzzy analysis of 42 phenotypic characteristics. Six clusters were formed below the boundary level of 0.75 average distance except 92-78-2 strain. We consider that six clusters should belong to the fast growers and slow growers. However, the properties of the two growers are correspond incompletely with the differential characters of the 4 genera in the rhizobial taxonomic system, for example, some strains can utilize starch as the sole carbon source. The results of numerical analysis also suggest that the primary basis of the division of the clusters is the phenotypic characteristics, and has nothing to do with the category and origin of the hosts. Our results indicate that tree rhizobia are very diverse with respect to their physiological and biochemical properties.

The isolations of soil microorganism in different developing stages of the Chinese fir plantation were investigated. It was found that the amounts of rhizosphere bacteria and the bacteria in juvenile and mature stands were higher than those of non-rhizosphere and the bacteria in medium stands.The amounts of actinomycetes have no significant change among rhizosphere and non-rhizosphere soils.The isolations were more abundant in juvenile and maturestands than that in medium stands in which only Albosporus, Flavus, Griseofuscus were found. The amounts of fungi significantly declined from juvenile to medium stands and increased to mature stands. The percentage of Penicillium in medium rhizosphere soil is higher than those in the juvenile and mature stands. The results suggested that the comparison of the rhizosphere and non-rhizosphere soils is useful to show the relationship between the change of soil characters and the Chinese fir growth, controlling soil degradation and improving production of the plantation.

Five structural polypeptides, with molecular weights of 120 kd, 116 kd, 110 kd, 66 kd and 33 kd, respectively, were found in SDS-PAGE profile of purified virus particles of Dendrolimus punctatus cytoplasmic polyhedrosis virus (DpCPV), Wenshan (Yunnan Province) strain. DpCPV polyhedron contains two major polypeptides of m.w. 30 kd and 28 kd. Four monoclonal antibodies, as 2D5, 2D10, 3D4 and 6B3, were prepared against purified DpCPV particles, and their subclasses were determined. These monoclonal antibodies were used in DpCPV detection by ELISA. Results obtained in vitro DpCPV replication in SFE-HA-8212 and SFE-HA-831 cells (ovarian cell lines from Helicoverpa armigera) showed that these cells were persistently infected, however, the release of virus particles into the culture medium was seldom demonstrated. In Western blotting, traces of viral antigens were detected in SFE-HA-831 cells 18 hours after DpCPV infection. Batches of Dendrolimus larvae collected from pine forests in Guangdong and Yunnan provinces were examined by the immunological detection technique described here. Results confirmed its efficacy in long-term monitoring of DpCPV in Dendrolimus control and its epidemics in nature.

A new species of genus the Diaparsis foerster, Diaparsis minquanensis Sheng et Wu sp.nov., collected from Minquan County, Henan Province, parasitizing Lema decempunctata Gebler (Coleoptera), with a Chinese new record, Diaparsis multiplicator Aubert 1969(Aubert JF, 1969)^[1], collected in Shenyang, Liaoning Province, is reported in this paper.

Fire is a primary factor of deforestation. Although in recent years the level of forest management and technique of fire suppression have been improving, fire fighting force has been strengthened, the area of fire damage is not apparently decreased. Using biological fire resistant technique can effectively prevent the campaign fire. In this paper, fire resistant ability and the component of leaves, twigs and barks of 12 tree species, in mountain area of Dagui mountains, Guangxi Zhuang autonomous region, were analyzed in laboratory. The results from this study indicated as the followings: (1)For all the tree species, fire resistant ability of leaf is more susceptible than that of branches and bark, and the broadleaf tree species are stronger tnan coniferous tree species in fire-resistant. (2)Calorific value, water content, compustion temperature and ash content are main indexes to affect fire resistantivity. Heat value relates to lignin content and benzene-ethanol extractive content linearly. (3)By means of the fuzzy mathematics method, the fire resistantivity about 12 tree species were put in order. Some of them such as Schima superba, Castanopsis hystrix, Myria rubru have strong fire resistantivity, Some tree species such as Machilus pauhoi, Mytilaria laosensis, Michelia macclurei, schima sp. and Manglietia tenuipes are relatively strong at fire resistantivity, the rest such as Cunninghamia lanceolata and Pinus massoniana have weak fire resistantivity.

In this study, the wood of Poplar 72 (Populus×euramericana cv.Ⅰ-72/58), Poplar 63(P.deltoides cv.Ⅰ-63/51) and Poplar 69(P.deltoides cv.Ⅰ-69/55)grown in three different beaches(river beach, islet beach and lake beach) of the Yangtse River with three different row spacings(3m×4m, 4m×5m and 5m×6m)were selected as the materials. Based on the relationships beween wood properties and the cambium age(CA), the ring width (RW) revealed, the fiber length (FL), the microfibillar angle(FA) and the wood density (WD) varied with CA and RW were firstly quantitatively modeled with stepwise regression analysis methods. The results are as follows:FL=765.07+119.77CA-6.15CA²-1506.97(1/RW)+365.18(CA/RW)-18.02(CA²/RW)FA=9.643+0.061RW+2.376(1/CA)-0.201(RW/CA)WD=0.447-0.003CA+0.004(1/RW)+0.004(CA/RW)It was revealed from the results that FL of poplar plantation can be better predicted with above model of FL varied with CA and RW(r=0.989) and FA and WD within a poplar tree can also be better predicted with above models of FA and WD varied with CA and RW(r=0.209~0.909), except for the prediction of FA and WD(r=0.118~0.143) among different poplar trees.

In this paper, the rheological behavior of perpendicular to the grain of 3 mm-thick surface layer of fast-growing poplar lumber was discussed. Four kinds of drying temperatures(85℃, 105℃, 115℃and 125℃) were applied to dry the lumber. The results show that the total strain that occurs in lumber drying is the sum of four components:elastic strain, shrinkage strain, visco-elastic creep strain and mechano-sorptive creep strain. When the lumber is under the joint action of the high temperature and high humidity for a long time, it shows not only an elasticity and a plasticity but also a viscoelasticity. The authors improved the traditional slicing method for determination of the dryint strain of the lumber in accordance with the theory of the wood drying stress model, and put forward for the first time a new testing method to determine simultaneously different strain parameters of the established model on the same piece of squared lumber.(1)The surface layer of the lumber can be greatly plasticized in the high temperature drying and the casehardening is formed. The major factors which affect the drying stresses of the lumber are the maximum values of mechano-sorptive strains both in and after the drying procedure. (2) In the initial drying period, the linear expansion coefficient across the grain of the lumber increases due to the high temperature. This means that the lumber does not shrink but expands instead. As for the conventional drying method, the lumber does not expand due to a rather low temperature in the interior of the lumber, i.e. it shrinks as soon as the drying procedure begins. (3)The tensile strain of the surface layer of the poplar lumber is not so big but the compressive strain is much bigger than the tensile strain. This is why there is no cracking on the surface layer of the poplar lumber at the initial drying stage but internal cracking and shrinkage appear at the later drying stage, especially with a high temperature. (4) It can be found that, through comparison made among the different drying conditions, the viscoelasticity strain reduces as the drying temperature goes up. Judging from the overall variation characteristics of the strains, it is not difficult to find that the value of the creep strain of the viscoelasticity is rather small. (5)The pure strain in the lumber due to the drying is an algebraic sum of all strains excluding the self-shrinking strain of the lumber.

The main purpose of this study on rosin in Masson pine (Pinus massoniana Lamb.) and its modification is to change the rosin content and its properties so as to eliminate the defects in pinus wood, such as deformation, split and rosin overflow. The properties of modified wood can be suited to the standards of industrial materials. That can be realized by the extraction with chemical reagents or fine solvent and a simple way for industrial production will be able to be obtained from our experiment.

The theory and techniques for steady-state mineral nutrition of plants, which is relative to the traditional mineral nutrition, is one kind of view in full new and experimental technique little short of being perfect.The main points of the steady-state mineral nutrition can be summarized as follows:(1) According to the requirements of the plants to supply the nutrients; (2) Suppling the nutrients in alow concentration which is close to the concentration of the natural soil solution; (3) Suppling the nutrients in a balanced proportion according to the requirements of plants.Based on the experimental technique proposed by T.Ingestad, the optimum growth of plants tested have been obtained so that the growth potential of plants has been tapped fully.For many years, the research fields of the steady-state mineral nutrition include the extension of range from tree species, ions, and experimental conditions, application of the theory to forest tree nursery cultivation, fertilization modles of forestland, and the related cross-study, as well as the study on the mechanism of the steady-state mineral mutrition from the matter metabolism and environmental conditions.The results have proved that the real relationship between growth and nutrition of plants has been revealed by the theory and techniques for steady-state mineral nutrition.

The paper put forward a conclusion of"Differentiated Forest Management is an Important Way towards Sustainable Development of Tropical Forestry ", which was verified and analysed by means of the theory of" differentiated forest management"for China's forestry development as well as the mid-term experimental results of currently implemented ITTO China Hainan Tropical Forestry Development Demonstration Project, which was executed under the guidance of this theory.The paper pointed out that the protection and utilization of tropical forests were a comprehensive issue integrating technical, economic and social aspects, and even with political, cultural and ethical factors.To solve this issue, "Systematic Theory" must be adopted with understanding of wider background.The paper also pointed out that the lessons in the past was confining the development of tropical forest to forestry and to technology.

Sustainable development is the knowledge and culture resulting from the progress in human civilization.It is a goal, idea and the common sacred cause for the whole human being.Education is the basis and rule by law is the guarantee for achieving this realm.Sustainable development is also a strategy and principle.It is the criterion to coordinate all relationships between regions or professions.Sustainable management of the forest is the basis of sustainable development of the forestry.It is one of the important components of regional orglobal sustainable development.It can not be realized without the attention from the government, the support from the entire peaple and the effort for centuries.

The content of an endogenous putrescine increased dramatically in four tree species of Robinia pseudocacia Linn., Liriodendron tulipifera Linn., Platanus acerifolia Willd and Gardenia jasminoides Ellis under acid stress, but the content of spermidine and spermine showed no change.The additional D-Arginine (an inhibitor of the putrescine biosynthetic enzymes) to acid medium could inhibited the level of putrescine.However a simultaneous additional D-Arginine and putrescine could reverse the inhibitory effects of D-Arginine.Under the acid stress, the balance of active oxygen metabolism was lost, the content of MDA was accumulated rapidly, the activies of SOD and CAT decreased.Applying exogenous putrescine to acid medium could regulate the balance of active oxygen metabolism, decrease the accumulation of MDA, while increase the activities of SOD and CAT.The results showed putrescine could protect plants from the acid stress.

The predicting models of cone crop/seed yield of Chinese fir seed orchard were established on Qifeng shan forestry farm in Yang xin County of Hubei Province by means of the method of visible crown, information section in crown, tree growth factors and climatic factors respectively.The results showed that there were closely linear relations of the number of female cones and immature cones of visible crown or of the optimum information section, and the crown diameter of the female tree with the cone crop of a tree. However, the predicting model via the optimum information section was most accurate among the cone crop predicting models while the predicting model via immature cones was more accurate than that via female cones.The number of seeds in a cress section of a cone and the cone volume could accurately predict the number of full seeds in a cone.A model via the key climatic factors for seed yield was accurate enough. Each model had its own merit on simplicity, applicability or the predicting period, but the tests of all models were at significant level and could be selected to use according to the requirement of practice.

The field trap test on Ancylis sativa Liu showed that E9-12:Ac alone had a little attractness to male moths, but Z9-12:Ac alone could not attact them.Mixtures of E9-12:Ac and Z9-12:Ac in five various ratios were tested, and the mean catches reached their maximum in the natural E/Z (6.5:3.5) ratio.The preparation in this ratio was used to study the relationship between doses used and mean catches. Within the range 50~200 μg the traps were effectively attractive to the males in the field.Little attractness to males was found in the dosage of 1 μg and 500 μg.

Breeding and cultivating G.uralensis with seeds, treating seed before sowing, sowing in a right period, harvesting in autumn when the age of root is 3-4-year-old and keeping seedlings density in 222~444 thousands per hm² are the key measures to obtain the root harvest with high quality and yield.