The study is concerned with some agroclimatological methods to compare with 10 climatic elements, which be taken from 7 weather stations of neighbouring county at north Jiangsu. It will be seen from this that shelterbelts produce a lot of good influences in ground-climate, in particular to represent a colding effect and a humidifying effect, which help to bring a good yield about food crops. However, shelterbelt system can't effect any variation of macroclimatic background if forest-cover rate in the place is existed as less than 20%.

Genetic variation within and among four populations of Korean pine forest in Northeastern China were analyzed at four loci coding for three enzyme systems.Isoenzyme variation within population. The mean value for all samples of the average expected heterozygosity over four loci was 0.37. The average number of alleles detected per locus was 2.25.Isoenzyme differentiation among populations. Our mesurement of gene diversity for the four loci showed a 2% significant effect of interpopulation differentiation. Ninety-eight percent of the total gene diversity resided within populations.The mean genetic distance over all pairwise combination of population was 0.025±0.008.

The influence of Diflubenzuron on the natural enemies of two species of pine caterpillars, Dendrolimus tabulaeformis & D.spectabilis, were reported in this paper. According to the results of laboratory experiments and extension tests in the pine forests, the insecticide did not significantly influences on the natural enemies, such as: Carcelia rasella, Casinaria nigripes, Leis axyridis, Arma chinensis, Anastatus sp., Beauveria bassiana, Paecilomyces farinosus, Coturnix japonica, Therefore when the concentrations of diflubenzuron are rational, the use of diflubenzuron for control of the pine caterpillars should be one of the best techniques in the integrated management of these pests.

The study reveals that four species (M. matsumurae, M.massonianae, M. koraiensis, M. dahuriensis) have obvious difference in their ultrastructure of sperms.The main difference appeared in the quantity of microtubules, their arrangging patterns and the angle of the microtubular row has been discovered.The key to four species is as follows:1.The microtubules are arranged in whorled radii patterns in the non-nuclear region……2The microtubules are arranged in spirale patterns in the non-nuclear region……32.The angle of microtubules row in non-nuclear region is 170°—190°……M. massonianaeThe angle of microtubules row in non-nuclear region is 30°—50°……M. koraiensis3. In the nuclear region, the microtubules are arranged in whorled radii patterns, the angle of microtubular row is 40°—60°……M. matsumuraeIn the nuclear region, the microtubules are arranged in whorled radii patterns, the angle of microtubular row is 90°—160°……M. dahuriensis

The rainfall interception in canopy of main forest types, litter storage in forest lands, dynamic changes in water contents, as well as its effect on rainfall interception in Liupanshan forests have been determined in this paper. The infiltration capacity of soil for water and its related factors have also been analysed. It was shown that the interception of rainfall in canopy of main forest types is about 16.2—29.1%, litter storage is 10—12 t/ha, its minimum water-holding capacity is equivalent to the rainfall in 3—6mm, the interception of mainfall in litter is 5.6—13.1%. There is a little water storage in non-capillary pore of forest soil, 233.5—1088.6t/ha in the arbor forest, 390—669t/ha in the bush forest, and 236—475t/ha in the grassland, thus water infiltration rate of soil surface layer is arbor forest, bush forest and grassland from higher to lower.

By measuring the prolongation, tension and radial contractibility rate of wire and rope of the over-long (39m) samples of double twisted wire rope(6×19+1, 6×37+1), the following conclusions can be obtained:1. Without displacements at both ends of suspended cable, its E_s has nothing to do with its length.2. When new wire rope is used as sample(its overtension is not tested in advance), r=0.37—0.414(r refers to the correction coefficient of E_s and tested 9 times).3. After pretension of newer wire rope, r=0.605—0.715.4. E_s is in direct proportion to the tension, and the relationship bet ween E_s and the safetly factor of tension is one variable and two degrees curve(Fig. 5).5. To deduce formula W in theoretical value of E_s in refrence[6], the corrected value of W is 2% less than the testing average valus of W, so accurate value of E_s can be obtained from formula[6].6. As to the selection of E_s, (0.37—0.414)E should be chosen for the skyline with short span (about 100m). It is suitable to choose(0.615—0.715) E for the cableway with longer span (about 500m).

Computer-aided identification for timbers is a fast and accurate method so far developed in wood science. In this paper a system for identifying 500 Chinese hardwoods has been presented, which consists of two programs: WIP (in Chinese) and WIP 1 (in English). This system has many additional functions, such as restooting the previous state, listing the different feature codes among 5 or less tree species as well as modifying information already inputed and adding information for new tree species. The data base consists of 23 multi-characters (Multistate characters) and 19 non-multi-characters(Dichotomous characters).Now there are two types of method dealing with wood identification features: One is Morse and IAWA'S suggestion which divides the wood features into dichotomous, multistate and quantitative ones, and the other is Weeler's opinion which is in accordance with the features of the multiple-entry perforated-card. The method adopted by the authors is in difference from the both methods previously used. Based on the kinds of the features which are divided into 8 groups, such as growth ring, pores, wood ray etc. and then the features in each groups are further divided into dichotomous and multistate ones. The botanical family names are expressed with three letters, i.e. the first letter and first and second consonant letters after that.

The knowledge of symbiotic associations with tree legumes is less well understood, yet that microorganisms appear on land with higher plant is of major importance in maintaining soil nitrogen in shrub and forest communities, therefore a generally historical background, current advances and research trend of the study of tree legumes nitrogen fixation have been discussed in this treatise, with appropriated introduction of some authors' research results and experiences.The major emphasis in the present review is laid on the nodulation of tree legumes. Within the legumes, however, the Caesalpinioideae are largely unnodulated, while the Papilionoideae and Mimosoideae are mostly nodulated. There are also several reviews concerning more detailed information on classification of nodule bacteria of tree legumes, possible factors involved in the inability to nodulate of tree legumes and so on.

In this paper reports that the so-called "Mohe Korean pine", found in Daxinganling in the late fifties of this century was proved to be of Pinus sibirica (Loud.) Mayr but not of P. koraiensis Sieb. et Zucc. by a series of research and investigation. On the contrary, the P. koraiensis has not distributed in Daxinganling.The main natural area of the P. sibirica is western and central Sibiria. In Daxing anling it only occurs in the northwestern border. That is a first discovery.In identification, the openings of the sunken stomata on the needles epidermis and their prints on the cuticle, in addition to general morphological characteristics, were also studied camparatively by combination means of dissecting, optical and scanning electron microscope. In this research discovered that the opennings of the sunken stomata, even in the epidermal cells, of the P. sibirica apparently differs from that of the P. koraiensis. That could be considred as a reliable diagnostic characteristics.

Studies on the microoganism and biochemical activity of forest soil in different site conditions of Chinese-fir plantation were carried out in Lilou Forest Area, Longshen County, Guangxi Autonomous Region. The results indicated that there were remarkable differences in different topography and soil types. The quantity and number of colonies of predominant groups of soil microoganisms in the black sandy soil in the valley and hillside were higher than those in the yellow and red soil on the ridge. In the same case, the biochemics of soil respiration and the biochemical activities (such as ammonification, nitrification, nitrogen fixation, cellulose decomposition, protease, invertase, catalase and polyphenoioxidase) of the former were higher than those of the latter. It showed that the productivity of the former was higher than that of the latter.

This paper describes 5 methods of soil preparation lead to the different influence of tree growth in rocky hill areas. According to the data of sample plot and statistical analysis, the double field preparation is the best one. Using this method, the physical property of soil can be improved evidently, the contents of organic matter and rapidly available nutrient can increase greatly. Both the survival rate and increment of trees are larger.

Castanopsis fissa and Schima superba are the two suitable and dominate tree species for fuel forest in the suburb of Wuzhou City in Guangxi Autonomous Region. Studies were conducted to find out the quantity of biomass in relation to site condition, density of crop and pure or mixed stand. The results are as follows:1. So far as site condition is concerned, the biomass of fuel forest at the foot of the mountain is the largest.2. So far as density of crop is concerned, in a certain range, the biomass increases with the increase of density of crop.3. So far as pure or mixed stand is concerned, the biomass of the pure stand of C. fissa per ha is more than that of the mixed stand, while S. superba is to the contrary.

The annual biomasses of trunk, branch and leaf of Populus gansuensis (Populus nigra var. italica×P. siminii), as a single tree and population, have been calculated by analogy simulation and average treemodular standard tree method respectively in this paper. The growth analysis of this tree species have also been carried out by classical method. The results are as follows:(1) By calculating the existed biomass, the percentage of trunk, branch, and leaf to the overground part of a tree(S₁%, B₁%, L₁%), tended to be stable from the 8th year, which is 77%, 18% and 5% respectively.(2) Based on the dry matter accumulated over 16 years, the percentage of leaf to the overground part of the tree amounted to 21.5%, and it would raise with the increase in age.(3) The leaf area ratio (LAR) of both an individual tree and a population trended to decrease during the investigation. The net assimilation rate (NAR) and the relative growth rate (RGR) tended to fall from the 8th year.(4) The leaf area index (LAI) of a population shot up with the increase in age during the investigation. The complex growth rate (CGR) raised sharply after the 5th year, and amounted to the maximum at the 8th year when the LAI was 9.1.

After tract was tested in two forest bureaus in Heilongjiang province, it was applied to provincial inventory. This paper showed the results of the test and the principle of this method. The authors derived two new applicable formulas, which had the advantage of the original one in forest inventory of volume-increment, area estimation and time efficiency.