The concentration, absorption of nutrients in 8 months old and 36 months old E. Leizhow No. 1, E. urophylla and E. citriodora were studied. The sampling time of leaves for nutritional diagnosis and the methods of nutritional diagnosis were discussed. The nutrition status of Eucalyptus in medium-expand experiment plots of Eucalyptus fertilizing were diagnosed by using diagnosis of eritical concentration and diagnosis and recommendation of integrated system (DRIS).The results indicated that the value of macro-nutrients concentration in leaves was the highest for all three Eucalyptus, that the Eucalyptus would absorped more nitrogen and potassium at 8 months old and absorbed more potassium and calcium at 36 months old. It was showed that the optimal time of leaf sampling in nutribnt diagnosis was at 8 months old for E. leizhow No. 1 and E. urophylla at 20 months old for E. citriodora. The critical concertration (g·kg^-1 of N, P and K for E. Leizhow No. 1 was 17.2, 1.3 and 4.9 respectively, and that of N, P for E. urophylla was 17.0 and 1.3, and P, K for E. citriodora was 1.1 and 9.6. The diagnosis parameters of DRIS should be K/P, P/N and N/K.

In this paper, the amount of carbon sequestered through large-scale afforestation and related costs and benefits are calculated, assuming that the forests are managed in perpetual rotations. Based on land availability for afforestation, 20 cases are identified in 5 regions of China. The least expensive way of developing forests for the purpose of sequestering carbon emissions is the case of Pinus massoniana from the initial investment point of view, and then Spruce. The cases of open forest management are relatively less expensive options because of their low initial investment and long rotations, although their annual wood increments are low. Some less productive tree species have higher net costs for carbon sequestering. For most of the agroforestry systems the net costs are low, especially in the south, the southwest, and the north of China, though their initial investments are high. If the total land available is afforested, the net carbon sequestering will be about 9.7 billion tons under perpetual rotations, amounting to 16.3 times of the total inustrial carbon release in 1988 in China, and the total initial cost for such a program is estimated at 19.3 billion US＄. Some hindrances in developing forests in China are discussed.

A combined Provenance family progeny trial of Eucalyptus grandis was established in Fujian in 1990 using seeds provided by the Australian Tree Seed Centre with 18 provenances and 147 open-pollinated families representing the whole range. Research results from the trial indicated that there were very significant difference in growth characteristics between families, and significant difference in wood basic density between provenances/families at age 4 years. Provenance 1, 4, 15 and 5 as well as family group A, B, C, D, E and F had higher wood density than the others. There was not a significant correlation between growth characteristics and wood density. It was found that the more significant genetic variation existed in all the characteristics between individuals, and hence individual selection would exceed family selection in genetic gain by 6%- 25%. The more genetic gain can be achieved by individual selection based on selection index values.

The black locust (Robinia pseudoacacia L.) is one of most important nectariferous tree species. Most of black locust forests are not fit for timber production. They are suitable for management as nectar source. Based on 490 sample trees and 81 plots, the flower mass of individual tree and stand of black locust were studied. The flower mass of individual tree is 0-5.2kg per tree. It is determined by its genetic factor. The flower mass of stand hasclose links with age, G, D, H, M, Wt, Ws, Wb, W, Wl et al. After analysis regression step by step, the main factors that affect the flower mass of stand were screened and the multiple regression estimation model of flower mass of stand was established. The growth dynamics of stand flower mass follows the Logistic.The fastest growing point is at 8 years. Its rapid growth period is at 4-12 years. There are significant differences between flower mass dynamics and the growth rules of stem, branch, leaf and root at the late phase of stand growth. These results are useful for the management of nectarferous forest.

61 strains of Bacillus thuringiensis belonging to 31 subspecies, preserved by two methods of sterie sand and filter paper for 1 - 23 years were tested. Their survival, morphological characteristics, toxicity against insects (Lymantria dispar) were measured. Physiological and biochemical characteristics and estarases of 5 subspecies of Bacillus thuringiensis preserved from 1979 to 1992 were determined.

The yunnan pine needle scale (Sonsaucoccus yunnansonsaus Young et Hu) is a major pest of yunnan pine (Pinus yunnanensis Franch) in Yunan Province. It has one generation a year in Kunming, and the adult appears from early April to late June, the egg appears from late April to late June, and the pupa which has the characteristics of sociality appears from early April to mid May. The ralations of its emergence with rain fall, daily temperature, forest type, host density and natural enemy were also studied. Its mortality has positive relation with rain fall and low temperature. Establishment of mixed for est combining with protecting natural enemy and killing pupae in pupal stage, may obtain significant effetiveness.

During the conference of forest pests protection held in China in 1990, it was urged by the State Forestry Department that computer network of prediction in forest pests should be established immediately and become the one part of prediction system of forest pests. Application of communication through computer network for prediction of forest pests was successful. It was carried on by Forest Protection Station in Fujian, Nanjing Forestry University, Nanping Forest Pretection Stationn in Fujian and Sanming Forest Protection Station in Fujian in 1994.The Fortune Fax communication system based on Great Wall Computers and distant telephone lines was used, according to HDLC communication rules. The distant computer network communication between cities (or regions) was realized at last, so that code information, numbers and prediction results of for est pest prediction could be sent out in fast speed immediately. It makes a breakthrough in the transndssion of prediction in formation of forest pests in our country, timeconsuming turns the conventional timeconsuming letter communication to fast computer transmission, which improves obviously the timeliness and precision of forest pests prediction and provides applied technique for computer network communication for forest pest prediction.

The radial variation patterns of wood density in Pinus elliottii and Pinus teada planted with different tree spacing in Hunan Province and Jiangsu Province were studied by x-ray wood densitometry. The main results obtained are: 1) Tree spacing affected the radial variation patterns of wood density components mainly on their average levels but insignificantly on the shape of density curves. 2) Tree spacing made significant effects on the average levels of the ring width curves and earlywood width curves, and the shape of ring width curves, earlywood width curves, and latewood width curves. 3) In the light of the results from loblolly pine, tree spacing influenced average ring density in two ways: to change the average level of the intraring density curves and to change the ring width so that it is not always ture that there is a monotonous negative correlation between tree spacing and wood density.

A series of basic formulas, which are used for designing saw chains and sprockets, were built upon contour parameters of new-type saw chains and sprockets by reference to geometry of usual chain drives. The formulas concern two kind of saw chains with same pitch and different pitch and three kind of sprockets, which are rim sprocket, spur sprocket and nose sprocket. Bumping, point contact, sliding, climbing, side clearance and fluctuating tension occur if the pitch of chain differs from the pitch of sprocket so that wear-and-tear of chain and sprocket, loss of power and probability of chain breaking and coming off increase and steadiness of cutting procedure decreases.

The international conservation organization IUCN has given international guidances on categorisation of protected areas for more than 20 years. Considerable achievements and experiences have been gained for the resources conesrvation and their wise-use around the world. So far as China is concerned, efforts in those aspects are just being started or almost on blank in other words. This paper disusses the follwing 2 parts. The first part consists of the background and the purposes of the categorisation of protected areas. Two category systems were recommended by IUCN CNPPA in 1978 and 1994, which were introduced, and examples applying the management categories were shown. On the basis mentioned above, the second part set a management category system of protected areas of China. It is hoped that they will contribute to the development of protected areas, especially to their management in China.

This paper develops a location model of storeyard. This model combines the following factors consistently: the metbod of dynamic economic evaluation, the net of timber transportation and the location of storeyard.

An oligonucleotide primer set (PaF/PaR) was designed for polymerase chain reaction (PCR) amplification of an approximately 1.2kb fragment DNA from Paulownia Witches' broom(PaWB) MLO on the basis of 16S rRNA sequence from O-MLO. Amplification of a 1.2kb DNA fragment from PaWB-MLO-infected plants DNA in total nucleic acid extrats of the host plant Paulownia spp., but no 1.2kb DNA fragment was observed when healthy DNA was used as a template. The study showed that the PCR method was able todetect PaWB-MLO in as little as 9.4pg of total DNA from infected Paulownia tissue culture plantlets.