Based on paper of “Theoretical derivation of risk-ratios for assessing wind damage in coastal forest”, wind damage in the pine coastal forest, which was thinned at four levels in December of 1997, was investigated for four successive growing seasons. Besides wind damage, the wind profiles outside and inside the coastal forest stand and the distributions of optical stratification porosity (OSP) were also observed. Based on these data, risk-ratios of wind damage for both individual trees and stands were estimated according to the methods developed in “Theoretical derivation of risk-ratios for assessing wind damage in a coastal forest”. The results showed that risk-ratios of wind damage, which were calculated from the mean height and diameter only and from the combination of wind and stand structure profiles, accurately predicted wind damage in the plantation. Relationships between different thinning ratios and incidence of wind damage showed that stand stability decreased soon after the thinning. This was due to the immediate effects of thinning on increasing the canopy roughness and wind load, and on decreasing the sheltering effects from surrounding trees. However, thinning strategies could improve the stability by long-term effects on growth and development of trees against extreme wind. Only canopy damage was recorded during the experimental period, no stem damage was found, even though the maximum 10-min wind speed outside the coastal forest attained 30.2 m s⁻¹. The results obtained in this study indicate that thinning is the most effective silvicultural strategy available for managing coastal forest despite the increased probability of wind damage soon after thinning.

Deforestation caused by the felling of trees for firewood is a major cause of environmental degradation in some villages in Luchun County, Yunnan Province. This is of particular concern in the headwaters of major rivers such as the Black River where increased runoff, erosion, and sediment yield impact on the millions of persons living downstream. While the links between forest clearance, the ability of the land to sustain production, and the sustainability of communities are understood, the pressures of having to survive today often cutweigh consideration of the consequences for tomorrow. The real challenge for these communities is that they recognise their situation and negotiate a practical solution rather than wait the intervention and support. It is essential therefore that the changes which have taken place are documented and their future impact illustrated. This information must then be portrayed in a manner that makes it accessible and comprehensible to all, even to those who are illiterate. For this reason the use of graphics offers considerable merit over textual and numerical analyses. This paper explores the use of MIGIS (an acronym for community based planning which integrates the techniques of PLA and GIS) to facilitate a negotiated, bottom-up approach to afforestation with the Hani farmers of Luchun County, Yunnan in southwest China.

The generalized Chapman-Richards model was derived from the Chapman-Richards function in which parameters η,k andm were unconstrained. Based on the structure of solutions and biological interpretations, the model could be classified into eight cases (three categories) at all and among them only 4 kinds of cases are suitable in forestry that represent four typical growth patterns of trees and stands. For each of 4 equations, the model properties and biological interpretations for parameters were discussed in detail. The generalized Chapman-Richards model was capable of describing a wide range of growth curves that was asymptotic or nonasymptotic, with or without inflection point. In order to illustrate the versatility, of the model, it was fitted to a group of data sets concerning the DBH growth of cryptomeria plantations with 4 initial densities and the DBH and height growth of natural Korean pinetree. Comparing the generalized Chapman-Richards function and the Schnute model, it was found that the parameters and expressions of the two models were interchangeable in theory, and the fitting results were explicitly identical in empirical applications.

With a data set of Eurasian forest litter fall based on 471 stands, annual litterfall was estimated to be 6.53 Pg dm·a⁻¹ (1 Pg=10¹⁵ g;dm, dry matter) in Eurasian forests, of which more than half occurred in tropical and subtropical forests, and a third in the boreal area. With litterfall, around 2.94 Pg C per year is transferred from the forest vegetation to the soil on this continent.

Inventory recorded 4 genera and 11 species of mountain bamboos in Shennongjia, Central China. Of these, 4 species (Phyllostachys nigra var.henonis, Ph. heteroclada, Ph. nidularia andPh. bambusoides) belong to the monopodial bamboo, 4 species (Indocalamus latifolius, I. longiauritus, I. wilsoni andI. tessellatus) to the amphipodial bamboo, and 3 species (Fargesia spathacea, F. murielae andYushania confusa) to the sympodial bamboo. Monopodial bamboos grow on the gentle slopes below 1800 m asl, occurring from the subtropical belt to the temperate belt in the vertical climatic spectrum of the mountain; Sympodial bamboos occur in higher elevations, ranging from the warm temperate (1200 m), across the mediate temperate and cold temperate, to the mountaintops of the frigid temperate belt (3100 m). Amphipodial bamboos occur in all climate types except the frigid temperate belt. Three dominant species,F. spathacea, F. murielae andY. confusa, currently cover 12%, 9% and 3% of the mountain ranges in Shennongjia, respectively.

With the help of GIS tool of ARC/INFO, ARCVIEW and FRAGSTATS, the map of forest resource distribution of Heilongjiang Province was analyzed in 1896, 1949 and 1981. Using total area, mean patch size, patch density, coefficient of patch size variation, mean patch fractal dimension and mean shape index, we studied the change of forest landscape pattern and the change of each patch types in this region. As a result, the total area of forest landscape and mean patch size decreased sharply, the quantity and density of patches increased, the juxtaposition of patches weakened, the shape of patch tended to become regular, and the border of patch simplified. All these showed that the forest landscape of this area tended to fragment gradually, and the fragment of Korean pine forest is the severest. The diversity of whole forest landscape and the evenness of landscape types distribution reduced gradually. Human impact, instead of climate change and forest community succession, is the most important reason for such dramatic changes.

The bark ofPteroceltis tatarinowii is a raw material for manufacturing Xuan Paper. The effects of Ca²⁺ concentrations on the accumulation of mineral elements in the bark, leaf and root ofPteroceltis tatarinowii were studied under controlled conditions. The types of Hoagland nutrient solution with three Ca²⁺ concentrations levels (200, 400 and 600 μg·g⁻¹) and a control (without Ca²⁺ were designed to culturePteroceltis tatarinowii. After 6 months, contents of seven mineral elements including Ca, K, Mg, Mn, Zn, Cu and Na in the root, leaf and bark were analyzed. The results indicated that Ca accumulations content in the root, leaf and bark had positively relation with Ca²⁺ concentrations (200, 400, 600 μg·g⁻¹), and the order of the Ca content in the three components was root>leaf>bark. Ca content in the root treated with 600 μg·g⁻¹ Ca²⁺ concentrations was 5.5 times as high as that of the control, and about 1.4 times as high as that of the root treated in 200 and 400 μg/g Ca²⁺ concentrations respectively. On the contrary, K and Mg contents in the root, leaf and bark were negatively related to Ca²⁺ concentrations, especially in the bark, and their accumulation trend followed the order of leaf>root>bark. K content in the bark treated with 600 μg·g⁻¹ Ca²⁺ concentrations was 39.3% of that of the control, and was 79.0% and 91.8% of that of the bark treated with 200μg·g⁻¹ and 400μg·g⁻¹ Ca²⁺ concentrations respectively; Mg content in the bark treated with 600μg·g⁻¹ Ca²⁺ concentrations was 23.4% of that of the control, and was 27.1% and 35.4% of that of the bark treated with 200 and 400 μg·g⁻¹ Ca²⁺ concentrations respectively. Compared with the control, the general tendency of Mn, Zn and Cu content decreased with increasing of Ca²⁺ concentrations and their contents were in the order: root>leaf>bark. Based on the results of this study, the experiment has been useful for providing academic bases in improving the bark quality ofPteroceltis tatarinowii on non-limestone soil.

Water relation parameters of bare-root seedlings of Chinese fir (Cunninghamia lanceolata Hook.) and Masson pine (Pinus massoniana Lamb.) were measured and changes of root growth potential as well as field survival rate of both species were studied after the bare-root seedlings were exposed in a sunny field conditiory. The results showed that Masson pine had a lower osmotic potential (−2.07Mp_a) at turgor loss point and at, full turgor (−1.29Mp_a), compared with Chinese fir (−1.80Mp_a and −1.08Mp_a respectively). The parameter V_p/V₀ (63.27%) of Masson pine was higher than that of Chinese fir (58.03%). This means that Masson pine has a stronger ability to tolerate desiccation, compared to Chinese fir according to analysis of above water relation parameters. Root growth potential and field survival rate decreased with prolonging duration of exposure. The field survival rate of both species was reduced to less than 40% after the seedling being exposed only two hours. Water potentials of −1.60 Mpa and −1.70 Mpa were suggested to be critical values for Chinese fir and Masson pine respectively in successful reforestation.

This paper discussed the characteristics of degenerated forest ecosystems in Changbai Mountain area, which include over-harvest natural forest, typical secondary forest, derived forest, and artificial forest. Forest cutting and regeneration methods that were historically used, in the region were summarized. They include diameter-class selective cutting, clearcutting, upbringing selective cutting, and selective cutting. We proposed cutting methods for the broad-leaved Korean pine mixed forest., spruce-fir forest, and larch forest. The measures for restoring the original mixed forest ecosystems were recommended.

The content of total sugar sucrose, fructose and protein in the leaves of 3-yr-oldBetula platyphylia was measured after the treatment by three exogenous sugar solutions (sucrose, fructose, glucose) and three high concentrations of CO₂ (700, 1 400, 2 100 μL·L⁻¹) for about a month in 1998. The results showed that spraying three exogenous sugar solutions increased markedly the content of sugar and protein of leaves under 700 μL·L⁻¹ and 1 400 μ L·L⁻¹ CO₂. The effect of spraying exogenous sucrose solution was the best among the three exogenous sugars. The treatment of spraying exogenous sugar solution and 2 100 μL·L⁻¹ CO₂ constrained the accumulation of total sugar and protein of leaves. There was no different in protein content of leaves when spraying glucose and fructose solutions under 700 μL·L⁻¹ and 1 400 μL·L⁻¹ CO₂. The treatment of 2 100 μL·L⁻¹ CO₂ concentration significantly increased the contents of total sugar, sucrose, fructose, and protein of leaves compared with that of the 700 μL·L⁻¹ and 1 400 μL·L⁻¹ CO₂ except the plants spraying fructose solution. There was positive correlation between the content of sugar of leaves and CO₂ concentration when spraying same exogenous sugar solution.

The age-structure of natural population ofZoysia japonica in Xiuyan County of Liaoning Province was studied by generational method. The results showed that the highest tiller age class was three, but 1st age class tillers held dominant position with proportions over 95% in each month during the growing seasons. The 2nd age class and 3rd age class tillers were minority in the population. SoZ japonica population was an expanding population. The zero age, class buds on the rhizomes were dominant in buds age structures. The proportion of buds to tillers on quantity in each month was about 30% to 40% and reached the highest at the end of September. The increasing of buds proportion before domancy guaranteed the quantity of tillers in the next spring. The biomass of 1st age class tillers changed with time. The biomass kept increasing from April to July and reached the highest at the end of July and then decreased.

The fresh pollen vitality, the effect of different storage conditions on the pollen vitality, and the difference of vitality among the species of seven species ofSyringa were determined in Shenyang, China. The results indicated that the pollen vitality (81.5%) ofSyringa villosa was the highest among the seven tested species, followed byS. microphylla andS. meyeri, and that ofS. oblata var.affinis was the lowest. The low temperature was the best condition for storage of pollen ofSyringa, and the most proper temperature for the storage was 0–2°C. The storability ofS. microphylla was the best of all, and it could be stored over 60 days at the temperature of 0–2°C, next wasS. villosa andS. meyeri.

The preliminary assessment of progeny test in a seed orchard ofEucalyptus globulus Labill ssp.globulus at Yipinglang State Farm of Yunnan Province in China was conducted. The trial was composed of 21 replications, with 2 trees on each plot, 15 plots in each incomplete block, and 18 incomplete blocks in each replication, laid out in aa-design of 270 open-pollinated families. The families were of three categories (natural populations, local land race and seed orchard). They were further subdivided into 11 regions. The data from an assessment of growth, stem form and other characteristics of the young trees after being planted 2 years were analyzed. Results are as follows the different categories differed significantly in their growth, with the families from seed orchards being the best. Regions also differed significantly in their growth. The families from the regions of Western Victoria, Eastern Victoria and all three seed orchards were better than others. The families from Yunnan had the best frost tolerant and its survival was the highest. For growth, stem form and fungal tolerance, the families from Yunnan were similar to that from Southern Tasmania and Eastern Tasmania. Two-tree plots were strongly recommended over singletree plot designs for large-scale progeny trials.

Bamboo was carbonized at different temperatures ranging from 200°C to 600°C. The dependence of the change of hemicellulose, cellulose, and lignin on the temperature was investigated by means of elemental analysis and Fourier Transform Infrared (FTIR) spectra of the residual solid products. The results showed (1) Below 200°C, hemicellulose in bamboo was decomposed and a large amount of hydroxyl groups are dislocated from hemicellulose and cellulose, accompanied by the evolution of water to escape (2) 200°C–250°C, cellulose in bamboo was drastically decomposed whereas the net structure of lignin keep stable, with the except of the dislocation of methoxyl groups from lignin. (3) 250°C–400°C, the net structure of lignin collapse, up to 400°C, followed by that the more position in aryl groups are substituted. (4) For bamboo carbonization, the aromatization of residual carbon has approximately completed at the temperature as high as 600°C. But the fusion of aromatic rings possibly does not occur.

Structural properties of forest soils have important hydro-ecological function and can influence the soil water-physical characters and soil erosion. The experimental soil samples were obtained in surface horizon (0–10 cm) from different subalpine forest types on east slope of Gongga Mountain in the upriver area of Yangtze River China in May 2002. The soil bulk density, porosity, stable infiltration rate, aggregate distribution and particle-size distribution were analyzed by the routine methods in room, and the features and effects on eco-environment of soil aggregation were studied. The results showed that the structure of soil under mixed mature forest is in the best condition and can clearly enhance the eco-environmental function of soil, and the soil structure under the clear-cutting forest is the worst, the others are ranked between them. The study results can offer a basic guidance for the eco-environmental construction in the upper reaches of Yangtze River.

The investigation was carried out on 10-year-old plantation ofFraxinus mandshurica in Maoler Mountain Experimental Station of Northeast Forest University. Tree height (H), diameter at breast height (D₁₃) and the increment of tree height in 5 years (H₅), the thickness of humus layer, as well as the soil moisture were measured for the plantation and the growth indexes (H, D_1.3, H₅) for different site conditions were analyzed. The results showed that main site factors influencing the growth ofFraxinus mandshurica were soil moisture, gradient and location of slope in order. The growth ofFraxinus mandshurica was better on the middle-or up-slope site than on the down-slope site. Soil moisture and late frost caused by terrain are the main reasons that limit the growth ofFraxinus mandshurica plantation.

This paper introduced the Genetic Algorithms (GAs) and Artificial Neural Networks (ANNs), which have been widely used in optimization of allocating. The combination way of the two optimizing algorithms was used in board allocating of furniture production. In the experiment, the rectangular flake board of 3650 mm×1850 mm was used as raw material to allocate 100 sets of Table Bucked. The utilizing rate of the pcard reached 94.14% and the calculating time was only 35 s. The experiment result proofed that the method by using the GA for optimizing the weights of the ANN can raise the utilizing rate of the board and can shorten the time of the desing. At the same time, this method can simultaneously searched in many directions, thus greatly increasing the probability of finding a global optimum.

Defibrator is a very important machine in the wood industry for producing fiberboard. The refiner plates are the key parts of defibrator that directly act with the wood, and broken easilly. The working life of the refiner plates is of significance to the wood industry. It may affect refining quality, production efficiency, and power consumption. In this paper, the abrasion resistance of the refiner plate made of different materials, the stainless steels and high chromium cast irons, were tested and compared. The results showed that abrasion resistance of refiner plate made of high chromium cast irons was better than that of the stainless steel materials. Although the two kinds of materials have the same compositions, their abrasion resistances have apparent difference. The main reason is that the material microstructures have very important effects on their performance. The refiner plates made of developed high chromium cast irons don’t demand the complex heat treatment. This can simplify the producing process, save the cost of production, decrease labor strength, and increase the production efficiency.