To ask adaptive responses of the S.vulgaris plants to different nutrient regimes in the fixed sandland, shifting sandland, and lowland in the poor nutrient Mu Us Sandland, the authors analyzed the following characteristics:soil nutrient regimes, biomass and nutrient allocation to various parts in the species growing in the contrasting haditats, nutrient use efficiency and resorption efficiency. The results were shown as follows:(1)there were differences in the contents of nitrogen (N), phosphorus (P), potassium (K), calcium(Ca), and magnesium (Mg) in the three habitats to various extents;(2)the ratios of biomass, N and P allocated to the leaves increased with the decreasing of soil N and P contents, these ratios allocated to the roots followed the opposite direction;(3)N and P resorption efficiencies, K use efficiency and resorption efficiency, and Ca and Mg use efficiencies increased with the decreasing of the corresponding soil nutrient contents, while N and P use efficiencies decreased with the decreasing of soil nutrient availability;(4)the contribution of the leaves to nutrient internal cycling was opposite with that of the roots to nutrient internal cycling; (5)root distribution exhibited various influences on heterogeneity of different soil nutrients.

Based on setting up the model system of growth-yield and management,according to management model system and technological economic guidelines of different distribution zone,the optimum cultivation patterns(total 23 patterns)of different zone and site index(every site index had 1～2 patterns)were obtained by using method of dynamic economic eveluation.Each pattern included 18 technology combination.Cutting age of the optimum cultivation patterns were 10～18?a shorter than that being used at present,their IRR were respectively raised 4～9 percent point than conventional cultivation patterns.Compared with building timber stands,planting density (3 100～4 500 tree·hm^-2) and harvest cutting density( 2 100 ～3 200 tree·hm^-2) of the optimum cultivation patterns for pulpwood stand were bigger and their cutting age were shorter 6～13?a with only one thinning or no thinning.Main technology combination of the optimum cultivation patterns were increasing suitably planting density,using middle spot soil preparation,in the north and middle zone first year tending one,the second and third year tending two every year,in the south zone the first and second year tending two every year,the third year tending one,above 14 site index no fertilizing,choosing provenances and families for planting,thinning one or no thinning,and early cutting suitably.

Based on located observations from a national key field scientific experimental station in Huitong, Hunan Province, the loss of the function and economic benefit of ecosystem's atmosphere purification due to Chinese fir plantation being clear-cut was analysed. After being clear-cut, owing to the end to photosynthesis of tree layer the ecosystem decreased the fixation of CO₂ by 17.24 t·hm^-2a^-1　and the emission of O₂ by 14.73 t·hm^-2a^-1,and the release of CO₂ was decreased by 16.64 t·hm^-2a^-1, and 9.775 t·hm^-2a^-1 was lost in the purification function of gaseous organism. By the economic means such as imitating market value method, the loss were estimated: 2 862 yuan·hm^-2a^-1 and 8 838 yuan·hm^-2a^-1 respectively due to the decrease of fixed CO₂ and emitted O₂, 2 762 yuan·hm^-2a^-1 due to the more release of CO₂, and 5 865 yuan·hm^-2a^-1 due to the less purification of gaseous organic pollutants. The total loss of ecosystem's purification benefit of atmospheric environment was amounted to 20 327 yuan·hm^-2a^-1.

Solid water is an ecological environment protecting product, which combines microorganism with chemical technology. Only when solid water contact with plant root can it release moisture gradually by the action of soil microorganism, and be absorbed by plant, at the same time providing the water for plant growth for a long time. Pinus tabulaeformis and Platycladus orientalis were selected to study the regularity of which solid water release moisture and the factors which effect solid water releasing moisture. As a result, the gross moisture and the rate of solid water releasing, the height that solid water decrease per day, and the relation of the quantity of solid water releasing and the area that it contact with the soil were concluded.

Samples were taken from Eucalyptus ABL12 plantation fertilized respectively with Leilin NPK mixture and Hydro NPK complexes using methods commonly applied. The analytical results showed that there were significant differences in the concentration of nitrogen, phosphorus and potassium in different organs of eucalyptus tree in the order:leaf>branch>bark>root>stem. The average nutrient concentration in eucalyptus (C) decreased with tree age(t) increasing, and its decreasing rate related to fertilization levels (Q). The total quantity of nutrient uptake by plantation(X) increased with t and Q increasing, while nutrient uptake rate (dX/dt) decreased with t increasing. This indicated high importance of eucalyptus stand nutrition in its early growing period. The nutrient uptake curve could be used for determining both the relative intensity of nutrient uptake and the net quantity of nutrient demand relating to stand growth at different stand growing stages, and was thus of high value both in theory and in practice in the dynamic management of stand nutrition.

By using auto-data collection system with thermal dissipation sap flow probe, meteorological and soil sensors, diurnal and daily sap flow velocity (SFV) and whole tree water consumption of Pinus tabulaeformis and Platycladus orientalis were measured in late autumn from Oct. 27 to Nov. 9 in the West Mountains of Beijing. Results showed that diurnal SFV started from 8:00, and ascended to the peak during 13:00～15:00, then went down to the valley after 18:00. SFV of P. orientalis was much higher than that of P. tabulaeformis at the same lower position. Diurnal fluctuation of SFV on lower and upper trunk positions of P.tabulaeformis was similar, but the starting time of SFV on upper trunk position was much earlier, and the SFV peak was higher and thinner compared with lower trunk position. Progressive daily and diurnal sap flux on lower and upper trunk positions were approximately equal during measuring period. Daily water consumption (DWC) gradually descended in November. DWC of P. tabulaeformis in Nov. 6 was only 1/5 of 5 days ago, and DWC of P. orientalis was nearly 0 at the same time. Diurnal SFV was deeply affected by environmental factors such as solar radiation, air temperature, air humidity, wind speed and soil temperature. Multiple linear models of sap flow velocity and environmental factors were developed at significant level,of which the important factors were soil temperature in depths of 5 cm and 20 cm, solar radiation, air humidity and wind speed. Models of daily whole tree water consumption of P. tabulaeformis and P. orientalis were cubic curves.

The basic features of photosynthesis and transpiration of three Chinese Fir (Cunninghamia lanceolata) stands of different density(1 667 tree·hm^-2, 3 233 tree·hm^-2 and 9 767 tree·hm^-2) were measured in the field. The results showed that the light compensation point, the light saturation point and the maximum photosynthetic rate of needles of different positions of crown and different ages were different. In the same layer of the crown, the photosynthetic rate (A) of the mature needles was of the law of the current needles higher than one-year-old needles and one-year-old needles higher than two-year-old needles. In the strong radiation the transpiration rate (E) of the needles at the middle crown layer was less than that of the needles at the upper layer. But in the weak radiation,E of the needles below the middle crown layer was higher than that of the needles at the top layer.Generally, the light saturation point was 1 000～1 900 μmol·m^-2s^-1PAR,but the light compensation point could be low to 4.780～30.114 μmol·m^-2s^-1.the photosynthesis and transpiration capacity of needles in different positions and of different ages in the same branch was different. The photosynthesis and transpiration capacity of the needles in hind part of a branch was less than that of the needles in the front and the middle, but higher utilization rate of quantum or lower light was found for current needles 0.006 60 μmolCO₂·μmol^-1PAR, one-year-old needles 0.017 94 μmolCO₂·μmol^-1PAR and two-year-old needles 0.012 97 μmolCO₂·μmol^-1PAR respectively. The maximum photosynthetic intensity was up to 13.335 μmol CO₂·m^-2s^-1. A/E of the needles in a branch changed in the range of 0.003 5～0.007 gCO₂·g^-1H₂O,and the needles in the hind was of lower A/E. Generally, the photosynthesis capacity of shined needles was 2～4 times of that of shaded needles. A and E of the needles at the top of the branches were stronger than that at both the middle and the hind, and two peaks existed for the daily change of A and E in the growing season for the current needles. It was found that the radiation, the air humidity or the vapor pressure was the key factors to control the stomatal conductance,A and E. The respiration was controlled by the temperature, the humidity of the around air and the boundary layer of the needles. The respiration was higher in day than that at night, and it was in single peak at noon. Good linear relationship was found between the E and respiration. In stands of different density, higher density meant lower average nitrogen content of needles and lower light saturation point and higher light compensation point which led the tree to tend to use the lower light and to be of week growth. In the three stands, for the needles with different ages, the stand of lower density was of higher photosynthetic intensity.

Different hypocotyls of Bruguiera gymnorhiza from Qiongshan, Sanya, Wenchang, Fangcheng, Haikang, Gaoqiao and Futian were collected and cultivated in the same ecological environment at Futian, Shenzhen. And a year later, the morphology growth and the physiological indexes such as water content, chlorophyll, free proline, catalase, electrical conductivity, photosynthesis, transpiration, etc. were analyzed. The results showed that there were significant differences in survival rate, basal diameter growth and physiological indexes among the seedings from different provenances. Of all provenances tested, Gaoqiao, Qiongshan and Sanya provenances were better; the photosynthetic rate and transpiration rate for Qiongshan and Sanya provenances were higher, and lowest for Gaoqiao provenance; the relative electrical conductivity for Sanya, Wenchang and Futian provenances was higher, and lower for Haikang and Fangcheng provenances; the catalase activity for Futian provenance was highest, and the content of free proline for Gaoqiao provenance was highest. The provenance of Bruguiera gymnorhiza from Gaoqiao was best to be introduced to Shenzhen Bay by a coordinate-synthetic-evaluation way according to Shenzhen Bay's ecological environment.

The effects of exogenous salicylic acid(SA) (5 and 10 mmol·L^-1)on activities of antioxidant enzymes in seedlings of Fraxinus mandshurica were analyzed in the present paper.Activities of superoxide dismutase(SOD) were decreased by SA,and reduced with the increase of SA concentrations,resulting in the increase of superoxide radicals.The activities of catalase(CAT) and ascorbate peroxidase(APX) were inhibited by SA,and their activities reduced with the increase of SA concentrations.Although the activities of peroxidase(POD)increased,H₂O₂ levels increased in leaves with SA treatment because of the inhibition of CAT and APX.The activities of glutathione reductase(GR) was decreased by SA,and reduced with the increase of SA concentration. In general,malondialdehyde(MDA) levels in leaves with 5 mmol·L^-1SA treatment were 35.19% lower than that of control,suggesting low concentration of SA reduced freezing injury in seedlings of Fraxinus mandshurica.

The flavonoids, anthocyanin, simple phenols, lignin and soluble protein of the leaves in Ginkgo biloba phyllomes were assayed in 1998～1999. The results indicated that there were two peaks of flavonoids content, one rested on July 4, and the other on Nov.1. The change trend of anthocyanin content with much fluctuation was similar to that of flavonoids content. Simple phenols content rose in the early stage, and reached its first peak on July 4, then its content valleys showed on Aug.1 and Oct.17 apiece. First peak of lignin content was later, and the second peak earlier compared with flavonoids content peaks. There were opposite trends between flavonoids and soluble protein during the early and late stages. It was proved that there was a positive significant correlation between flavonoids and simple phenols, and anthocyanin, and lignin apiece. Positive significant correlation between flavonoids and protein also existed from the middle July to the late September. However, only negative significant correlation between flavonoids and protein was obtained by the analysis of partial correlation. The relationships between flavonoids and its transforming products, and precursors, and competitors were discussed.

The result showed that Camellia oleifera was mainly distributed between 23°30′～31°00′N and 104°30′～121°25′E,spanning 11 provinces in the south of China, where the climate is one of intermediate subtropical moist monsoon types. The classification of site types provided the technical methods for selecting suitable sites to grow this valuable table oil species. Thirty two site areas were classified according to the studied climatic facotors, and oiltea camellia cultivation in the future should be confined within those limits. According to geomorphology, slope and soil depth, 36 site types were generated further.

Seeds of Juglans nigra L.stored for one year under 0～5 ℃ were adopted in this research to investigate the effect of stratification ways on seed water content, endogenous hormon content, germination and following seedling growth. The period of stratification was highly required by the seeds of J.nigra to make a successived germination and later-on vigor growth. It was slower for the seeds to absorb water during stratification. As reaching saturation water content, the seeds were available to germinate. The higher the seed water content was before stratification, the shorter the time to be used to reach the saturation water content would be. The dormant seed contained lower level of GA₃ and high ABA. As the stratification process, GA₃ showed an obvious increase and ABA a sharp decrease, finally to zero. The rate of GA₃ to ABA might be an inner factor to control the seed germination. Among the stratification ways, the treatment of soaking the seeds in water for 5～6 days and then stratifying them at 2～5?℃ for 120～150 days presented the best and seed germination rate could be achieved as high as 75%. Although moisture absorption pretreatment could retard seed water absorbing, mosture absorption treatments showed no promoting seed germination. The stratification under low temperature had a significant effect to promote seedling growth in the following growing season and the promoting effect was enhanced as the stratification time increasing within a certain extent.

The effects of density regulation and rotation harvesting shoot on the shoot and young bamboo growth were studied under the different experimental treatments.The results indicated that:①The number of 1 year old daughter ramets in the treatment of 4～5-year-old mother ramets cutting was 1.92 times over that in the no cutting treatment; ②The rotational harvesting shoot improved the growth of daughter ramets, so the growth increments in height and diameter of 1 year old ramets were 1.5 and 1.4 times than those without treatment; ③There was a tend that the daughter ramets become short under the condition of current annual shoot picking.

The titres of haemolymph juvenile hormone(JHⅢ) of the last instar and diapausing prepupa of the sawfly Chinolyda flagellicornis were determined by high performance liquid chromatography(HPLC). In the last instar, the titres of JHⅢ dropped sharply, but still maintained in mid titres(about 17 ng·mL^-1). The titres of JHⅢ of diapausing prepupa maintained in a higher level(about 20 ng·mL^-1), and over 30 ng·mL^-1 in the day before pupation. It seemed that the diapause of Chinolyda flagellicornis was regulated by JH.

Based on the runoff plots in Suide, Yan'an, Lishi and Ansai area on the Loess Plateau, the benefits of runoff and sediment reducing by woodland and the effective converage of woodland for soil and water conservation under different rainfall conditions were analyzed in the condition that rainfall index used in the analysis is bigger than that of erosive criterion of sloping field, i.e.PI₃₀>3.20mm²·min^-1 & I₃₀>0.28mm·min^-1 ; and the effects of preparing works to erosion reducing for soil water conservation of woodland were discussed. The soil and water conservation index of woodland with different coverage in different rainfall conditions were established (V=0～100;PI₃₀=3.20～100mm²·min^-1):R_%=160.426 - 28.906 44(1/V) - 37.442log(PI₃₀·V),r=0.835^{* *},　n=88　S_%=161.953- 31.03189(1/V) - 30.985log(PI₃₀·V),r=0.682^{* *},　n=88

Acording to grey-system theory, two forceasting models(Grey-Model of disaster change) of forest fire's high risk age and forest fire's Mass Hazards Age were founded, which were based on the systematic analysis of the forest fire disciplinary occur in Daxingan Mountain forestry of Inner Mongolia. The verify precision of model simulating comes to first level, its expand modulus(-a) was less than 0.3. So the two models could be used as medium term or long term forecasting on the Daxingan Mountain forestry's disaster changes. The results showed that there will be three are three high risk fire years and five heave risk years during 2001 to 2010. Their lagging time will be 2 to 3 years, which precisions were higher than 98%. 2007 will be the Forest Fire's High Risk Age and the Forest Fire's Mass Hazards Age, with precisions of 98.05% and 99.78%.

Theoretic analysis for elastic modulus of softwood was carried out in this paper. It was assumed that softwood cell comprises tracheid and wood ray, and the models of tracheid and wood ray cell were presented. The tracheid was modeled as a hollow cuboid with two wedged close ends and ray cell as a hollow close cuboid. Based on the two models and following the hypothesis of cell wall consisted of MP composite layer and S1, S2 and S3 composite layer, the calculative formula was derived for longitudinal elastic modulus of tracheid and wood ray cell by means of elastic bodies in series and in parallel. Meanwhile, the method was given to calculate the longitudinal elastic modulus of coniferous sample according to the elastic behavior and the arrangement of tracheids and wood ray cells within softwood. Work done in the paper reveals the relationship between the macroscopical elastic behavior of softwood and its anatomic structure as well as the micro elastic behavior of softwood cell. It can not only obtain much knowledge toward the mechanism of softwood elasticity but also be useful to estimation of the longitudinal elastic modulus of softwood.

The fire retardancy of FRW,a new fire retardant for wood,was systematically studied by cone calorimeter and Dricon fire retardant was used for comparison.The cone calorimetric results showed that:(1)at a heat radiation of 50kW·m^-2 ,the Heat Release Rate (RHR) and Total Heat Release (THR) of FRW treated wood decreased considerably with the increase of FRW retention,but this decrease slowed down as the FRW retention was near 10%(Wt/Wt),and the RHR and THR values of FRW treated wood were about 50% of those of the untreated wood;(2) the curves of Effective Heat of Combustion(EHC) of FRW and Drion were nearly the same,which suggested that the fire retardant mechanism of FRW is similar to Drion;(3)the curve of Mass Loss Rate (MLR) of FRW was similar to its RHR curve,and the weight loss and heat release of FRW treated wood took place mainly in the flaming period of combustion;(4)the FRW treatment of wood could drastically increase its charring,while its ignition time was not influenced too much;(5)the fire retarding efficiency of FRW is similar to Dricon and both of them are highly effective fire retardants.

Because different wood-rot fungi have different physiological properties, and they can produce different enzymes with different activity, different wood-rot fungi degrade different compositions of wood with different velocities, and the middle materials degraded by different wood-rot fungi are different. In order to offer a applicating basic theory study to biopulping with david poplar wood, and offer a related study to microbial conversions of lignin to useful chemicals, biobleaching, enzymes treatment preventing from becoming yellow of mechanical pulping, wasted water control, microbial pretreatment of cellulose sugaring by enzymes, and decrease environment pollution in paper industry and make full use of lignin resources, this study selected Phellius igniarius and other 5 wood-rot fungi with higher wood degrading ability living on broad leaf trees, i.e. Funalia gallica, Lenzites tricolor, Polyporellus brumalis, Pseudotrametes gibbosa, Pycnoporus sanguineus, tested their degrading ability to david poplar wood lignin, measured the lignin content change of david poplar wood after a period of time degraded by 6 wood-rot fungi, which is the first study on the biodegradation mechanism of lignin by wood white-rot fungi. Under sterile conditions, the standard david poplar wood samples were put plate media of 6 species white-rot fungi and degraded by them. After 40 d, 60 d, 80 d and 120 d, the rotted wood samples were taken out respectively and the mycelium on the wood samples were brushed off. Then the lignin contents of primitive wood sample and rotted wood samples were measured. Results showed the lignin degrading ability of 6 species of wood white-rot fungi is different, it is Pycnoporus sanguineus, Pseudotrametes gibbbosa, Polyporellus brumalis, Lenzites tricolor, Funalia gallica and Phellius igniarius in turn. If considering the degraded extent of cellulose, Polyporellus brumalis is the better wood white-rot fungi with higher ability of degrading lignin and lower ability of degrading cellulose.

The growth volume of Acacia auriculiformis tree was investigated at the same age and the different forest stand,its chemical composition was determined and utilization of pertinent regions were studied.The results showed that the volume of timber and the biomass of the tree had increased by 14.8% and 43.4% respectively when it was compared coppice stand to seeding stand.It proved that the young trees developed from fastgrowing species would be fastgrowing in its early period.Its wood properties were changed a little by its forest stand.Its average basic density is lighter than 0.60 g·cm^-3,its fiber length is 898～916 μm,its radio of wall to cavity is 0.56～0.6(<1),and its fiber suppleness proportion is 59.3～ 68.5(it is among the range from 75 to 50).The yield of screen stock is more than 44% when pulping by Kraft process,the quality of wood pulp meets the standard of hard wood KP pulp.Acacia auriculiformis is the perfect host of Lac insects.The yield of tree stick lac from coppice stand is higher than that from seeding stand;The net increase production of tree stick lac is 1.42kg.The chemical composition of wood was almost the same and that of the bark was different slightly when the trees were stocked by lac insects,and the tannin amount of bark reached to 9.97%～11.40%(>8%)also.The product quality and the properties of tanning extracts made from this bark were better than the first degree of GB2619 81.When the trunk and branch is used for culture medium of domestic fungus,such as Pasania fungus,the yield of Pasania fungus and biological efficiency were remarkable higher than control groups.The optimum utilize process was studied depending on economic benefit exploiting from vary products. The best economic benefit will be yield from the artificial forest of Acacia auriculiformis when the following process is followed.Firstly,the 3-year-old coppice stands were stocked by lac insects. Then cut was down after collecting the tree stick lac and debarking the trunk and the branch.Thirdly,the debarking trunk and branch was used for culture medium of domestic fungus and the bark was used for producing tanning extracts.

This paper used larch particle and self made isocyanate resin, studied that how the factors of particleboard manufacturing, which is the density, pressing temperature, pressing time, moisture content, resin consumption and wax consumption affected on the difference of 24 h TS and irTS of particleboard by orthogonal double experiments, and studied the effects of particle materials and the adhesives in common use on the difference by one factor double experiment, it showed only the density of the board and the particle materials are the notable factors affected the TS Parallelity. Through analyzing some results of scholars' experiments, it found that particle geometry and particle pretreament are two another notable factors affected the TS Parallelity. The reason of the former is resulted from the different velocity and extent of wood absorption swelling, while the latter are from the difference of wood absorption caused by the conditions of experiments.

Combination strength on interface is an important parameter in the mechanical research of interface. Building a testing system that is quantitatively characterizing the particles and adhesives interface combination strength, analyzing factors of influencing interface combination strength, integrating microcosmic specific property on interface with macroscopic mechanics function of artificial board, thus realize the optimization of control on board technology processing. The established microcosmic mechanics model correctly describes interface combination status of particles. Shearing stress and direct stress can be separated by limited unit law analysis, thus demonstrated the interface destruction is due to shearing stress. The end of glue layer interface of pulled particles is the weak point of combination. The established test method for interface combination strength is feasible.

East Asia is very rich in the genetic resources of haploxylon pines consisting of 11 species and 2 varieties of Sect.Cembra Spach and other 2 species in Sect.Parrya Mayr. Of these taxa Pinus armandii, most widely distributed, and P.koraiensis, which naturally ranged in China, Korea Peninsula, Japan and Far East, are the most commercially important for wood production, logically, the most research has been carried out in genetic variation, tree improvement and gene conservation for these two species.P.fenzeliana and P.kwangtungensis, which are locally used in plantations, along with other 5-needle pines are mainly studied in taxonomy and ecophytogeography. P.bungeana and P.parviflora are not planted for commercial purpose but ornamental. Attempt is also made in this review paper to give an overview of tree improvement for the 5-needle pines.P.wangii, P.dabeshanensis and P.gerardiana still remain on the status of less known species. To develop a strategy for tree breeding and gene conservation, it is urged that more research should be undertaken in the patterns of genetic variation and advanced breeding programmes assisted with genetic markers.

Primary resistance of host trees directly effects the infection of bark beetles, secondary resistance of host trees restrict the colonization and brood development of bark beetles in the host tree tissues.The resistance of host trees decides invasion number of bark beetles and impels bark beetles to symbioses with special fungi. The symbiotic fungi of bark beetles effect the physiological metabolism of host trees to weaken host trees resistance, so that, creating essential existance condition for bark beetles in the host tree tissues, and inducing existance strategy of bark beetles' high evolution in suitable to the symbiotic fungi and host trees resistance, result in bark beetles cooperated evolution with host trees and symbiotic fungi.

The Economic and ecological effects of the Apple Pleurotus ostreatus system on ecology, physiology and yield in the hilly land of Taihang Mountain were studied, comparing with the pure apple tree stand(CK). The results indicated that: (1) The ecological environment of Apple Pleurotus ostreatus system which spacing is 3 m×4 m between the trees planted in 1991 was good for growing. (2) The content of organic matter, readily available N and K in the 0～50 cm soil increased by 45.8%, 31.0% and 39.3% respectively. (3) The content of chlorophyll and the photosynthetic rate of the apple tree leaves increased by 19.7%～23.3%, 5.9%～25.6% respectively. (4) The yields of Pleurotus ostreatus and its net income was 4 500 1 kg·hm^-2, 609.0yuan·hm^-2(RMB) respectively.(5) The yields of apple increased by 7.5%. (6) The total net income of the system increased by 7 025 yuan·hm^-2(RMB).

Sabina vulgaris is a unique evergreen conifer shrub and expands its area by the growth of stolon along the ground surface on which adventitious roots are formed and absorb water and nutrient. Therer is notable difference between the thickness of sand layer and sprouting of adventitious roots, especially between the great thickness sand layer and the other three types. Minor thickness of sand layer is enough to better off the soil water content in the soil layer (0～10 cm),while the soil moisture content decreased on the condition of great number sprouted adventitious roots, as a result, it is difficult for the adventitious roots to sprout. When the soil moisture content is below 1.0%, it is a question for adventitious roots to sprout. The adventitious roots was able to sprout on the 2-year-old stolon on the condition in which the sand is easily accumulated, even on the 9-year-old stolon on the medium and great thickness of sand layer. This indicates that the age is not the key factor for restricting the adventitious roots to sprout.

Protein in alcohol diversity was tested for the endosperm of Pinus massoniana from natural population using vertical slab polyacrylamide gel electrophoresis. 26 patterns of protein in alcohol diversity and 11 allele loci were obtained. The results indicated the ratio of polymorphic loci was 72.7%(P), mean number of alleles per locus was 3.636(A), mean effective number of alleles per locus was 2.663(Ne) ,mean expected heterozygosity per locus was 0.552(He), mean observed heterozy gosity per locus was 0.231 (Ho) and fixation index was 0.557>0(F) .It showed the population had higher genetic diversity, and pure individual was excessive.

The article summarized the species diversity index and regeneration of young Linzhi spruce stand at Linzhi region in Tibet. It showed that the diversity index of the young Linzhi spruce stand community was high. The Simpson diversity index is 0.871, while the Shannon Wiener diversity index is 3.976. But the diversity index of arbor layer of young Linzhi spruce stand was lower. Its Simpson diversity index was 0.336,the Shannon wiener diversity index was 0.899. Linzhi spruce occupied 89% of the regeneration sapling.Its average basal diameter, average height was 3.5cm and 125cm respectively. The linzhi spruce regeneration sapling grew well. The authors suggest that local forestry bureau should carry on closing hill for afforestation in this area continually. At the same time, artificial regeneration measures should be taken to improve the young Linzhi spruces crown density.

According to the genetic difference detected by means of RAPD markers, the methods of distinguish among 2 Liriodendron species and their interspecific hybrid were discussed, and the relationship between genetic distances of parents and their hybrids performance were analysed. Of the total 136 bands amplified with 25 10-mer primers, 3 presented in all 5 L.chinense sample trees, but absented in all 5 L.tulipifera sample trees. On the contrary, 8 presented in all 5 L.tulipifera sample trees, but absented in all 5 L.chinense sample trees. The 11 fragments could be detected in all the 6 hybrids sample trees. It was considered that 11 fragments could be used as markers in the identification. The range of genetic distance among 5 L.chinense sample trees, among the sample trees between L.chinense and L.tulipifera and between L.chinense and the hybrid were not overlapped. Therefore, the genetic distance between an unidentified tree and a L.chinense tree could also be used in the hybrid identification. The 16 sample trees were grouped correctly. So, the UPGMA (unweighted pair group methods of arithmetic (average))cluster analysis method was useful in the (hybrid) species identification. The mean height and basae diameter increment of families after the first growing season showed a significant guadratic cure correlation with genetic distances of parents. Therefore, the genetic distance had high potential for the choice of parents and the heterosis prediction in cross breeding of Liriodendron.

The number, weight, volume, density, shape and distribution of the root nodules were investigated in three different Casuarina equisetifolia plantations in Haikou, Hainan Province. The results showed that the biomass of root nodules in the sandy tidal soil was biggest, much bigger than that in sandy wind blown soil and sandy alluvial soil. The nitrogen content in soil was the most important factor that affected the biomass of the nodules. The other physical and chemical properties of the different soil types also affected the number, volume, shape and distribution of the nodules in soils.