The sap flow of Larix principi-rupprechtii, which is one of the most principal species for afforestation in northwestern China, was researched by means of heat pulse method. The results indicated that the sap flow changed regularly from day to night in later growth season. In the night, it was very slow and the value was usually below 0.000 08 m³·h^-1,and became stronger with increasing of solar radiation intensity and atmosphere temperature in daytime, and the maximum could reach 0.001 079 m³·h^-1. The results also showed that the sap velocity of points of stem section from outer to inner accorded with the law that the velocity is slow-quick-slow. The daily transpiration of individual tree was estimated on the basis of calculation of daily cumulative sap flow, at the same time, the cut tree experiment was done to validate the value. The study showed that the results were not different significantly using two methods, and the later value (0.003 17 m³·d^-1) was 8.2% higher than the former, because the logger was not enough sensitive to record low sap flow. And the stand daily water use for transpiration was estimated by applying to DBH and sapwood area as two scalars to scale up based on individual tree measurement respectively. And the former value was 0.64 mm·d^-1, which was 0.051 mm lower than the later. At last, the relationship between daily transpiration and environment factors was studied by correlation analysis. The result showed that solar radiation intensity, atmosphere temperature and relative humidity were three significant environmental factors to determine daily transpiration water use, and the regression equation was constructed accordingly.

Soil respiration and its seasonal change of forest of Pinus tabulaeformis and Quercus aliena var.acuteserrata were studied by using the seal respiration tube.The results showed that (1) there were significant correlations between soil respiration rate air temperature or soil temperature,and the correlation of soil respiration rate and soil temperature was better than that of soil respiration rate and air temperature;(2)roots' respiration was calculated by setting a equation of soil respiration and roots biomass;(3)The carbon dioxide released from forest land of Quercus aliena var.acuteserrate was 28.252 t·hm^-2a^-1,of which carbon dioxide released from respiration soil roots and litter layer were about 67.5%,23.81% and 8.69% respectively.The carbon dioxide released from forest land of Pinus tabulaeformis was 22.323 t·hm^-2a^-1,of which carbon dioxide from soil,root and litter layer was 61.01%,31.14% and 31.14% respectively.

In the same or semblable planting sites, in the seasons of summer and autumn, the parameters of hydraulic architecture of four young Pinus tabulaeformis were measured in improved flushing method. The parameters were hydraulic conductivity (K_h, gm·Mpa^-1min^-1, the weight of oxalic acid solution through the xylem per minute and per pressure gradient),leaf specific conductivity(LSC, gm·Mpa^-1min^-1g^-1, hydraulic conductivity per dry weight of supplied leaves),specific conductivity(K_s, gm·Mpa^-1min^-1cm^-2, hydraulic conductivity per transverse sapwood area),and Huber value(HV, cm²·g^-1, transverse sapwood area per dry weight of supplied leaves). The study indicated hydraulic conductivity was influenced not only by the stem diameter, but also by the location of stem.The hydraulic conductivity of restriction area (namely in the base of the fork) was evidently lower than that of non-restriction area. Meanwhile, every parameter of hydraulic architecture was influenced in a way by the relative ramification rate, crown layer and ramification direction. To some extent, these characters expounded the biological trait of Pinus tabulaeformis, and determined its ecology strategy of drought resistance.

The responses of the growth and the allocation of photosynthetic products in Chinese fir seedlings to N, P fertilizer and NP compound fertilizer under the N-deficiency and P-deficiency conditions in the soil were studied in this paper. The main results were as follows: (1) Under the N and P stress, N fertilizer accelerated the growth of two-year-old seedlings in some degree and the accumulation of photosynthetic products moved from roots to leaves. This showed that the N stress had been relaxed gradually. The use of P fertilizer, which caused the movement of photosynthetic products from roots to stem and leaves, indicated that the increase of P fertilizer could alleviate and sometimes could eliminate the P deficiency of one-year-old seedlings. By contraries, the P fertilizer caused the movement of photosynthetic products accumulation in 2-year-old seedlings from stem to roots. It showed that the P stress had not been eliminated essentially in 2-year-old seedlings with the increase of P concentration in soil and 2-year-old seedlings needed more N than 1-year-old seedlings. Hence, it was very important to use the balance NP compound fertilizer properly on seedlings at different growth stages. (2)Under the N-adequate and P-deficient situation in soil, the application of NP compound fertilizer caused the movement of photosynthetic products accumulation in 2-year-old seedlings from roots to stem (the rate of moved accumulation was 0.50%～3.13%) and leaves (the rate of moved accumulation was 7.21%～11.76%),and also revealed the elimination of P deficiency.

This paper dealt with variation of chemical elements and relationship between the elements in various vegetation types and plant life forms of Hainan Province,based on the analysis of 15 elements in plant leaves of 80 species.The results showed that:there were big ranges of element concentrations in plant leaves among the species or elements.The vegetation types and plant life forms had the obvious effects on element concentrations in plant leaves.N/P ratios were small for most vegetation types of Hainan Province.This indicated that N concentration was a major limited factor for plant growth.It was pointed out by the analysis of element ratios and correlation coefficients that plants had relatively constant composition and coordinated relationship for necessary nutrient elements.

The ability of drought resistance of Acer ginnala,Malus baccata,Prunus davidiana and Pyrus ussuriensis was studied under four soil moisture treatments (relative soil moisture content 75%、61%、46%、35%, respectively) by planting seedling in pots in greenhouse. The water parameters were calculated by using Pressure-Volume technique,and the drought resistance of four species was comprehensively evaluated. The results showed, under drought conditions, P. ussuriensis was the best in terms of water absorbing;all of four species had some extent of osmotic adjustment and turgor maintenance abilities. A. ginnala, P. ussuriensis, and P. davidiana could adjust osmosis by improving the proportion of bound water to some extent, when the soil moisture content decreased to 61% (for P. davidiana,and A. ginnala) and 46%(for P. ussuriensis), their osmotic adjustment ability by improving the proportion of bound water disappeared. Under drought conditions, P. davidiana and A. ginnala could maintain turgor by improving elasticity of cell wall, while P. ussuriensis and M. baccata maintained turgor mainly by osmotic adjustment. Water stress could increase the abilities of maintaining maximum turgor of P. davidiana, M. baccata and A. ginnala, but decrease the abilities of maintaining maximum turgor of P. ussuriensis. A. ginnala could adapt drought stress by improving the ability of tolerating dehydration, but M. baccata and P. davidiana could not. We concluded that the ability of drought resistance of four species was M. baccata>P. ussuriensis>P. davidiana>A. ginnala by integrating their osmotic potential adjustment and turgor maintaining abilities.

The 2-year-old seedlings of two litchi(Litchi chinensis Sonn.)cultivars grown in pots with different drought-resistance were used in this study.“Chenzi” grown in riverside is considered to be drought-sensitive,while “Dongliu 1” grown on hills is considered to be drought-resistant.Effects of water stress on some enzyme activities related to respiratory metabolism in litchi leaves were studied.The results showed:(1)Under water stress,the relative water content(RWC) of litchi leaves decreased,and the extent of decrease was less in drought-resistant “Dongliu 1” than in drought-sensitive “Chenzi”. (2)Under water stress,the activities of Mg²⁺-ATPase and Ca²⁺-ATPase in mitochondria of litchi leaves increased,and the activity of glycolate oxidase decreased.The extent of Mg²⁺-ATPase and Ca²⁺-ATPase activities increase and the extent of glycolate oxidase activity decrease in drought-resistant cultivar were higher than in drought-sensitive one.(3)The activities of Glucose-6-phosphate dehydrogenase(G-6-PDH) and NADH-cytochrome c reductase(NADH-CCR) in the litchi leaves decreased and the ratios of NADH-CCR activity/G-6-PDH activity increased under water stress.The extent of G-6-PDH and NADH-CCR activity decrease and the extent of NADH-CCR activity/G-6-PDH activity increase in drought-sensitive cultivar were greater than in drought-resistant one.

Effects of Larix kaempferi pruned in different types on growth and cutting production of ortets,cutting rooting ability and growth of 2-year-old rooted cuttings were compared at different ages (from 2-year-old to 10-year-old) of ortets. The result showed that ortets originated from L. kaempferi seedlings were cut at a height of 20～140 cm and trimmed or pruned each year could delay the time of occurrence of aging effect and reduce the effect to some extent. Rooting percentage of cuttings taken from 10-year-old ortets pruned in different types,which was 55.2%～81.1%,were extremely higher than that of cuttings taken from ortets of tree form in the same age,which was 24.8%.This showed that pruning each year could rejuvenate the tissue of ortets when they got older. Ortets pruned in different types resulted in different growth (diameter above ground), cutting production and rooting percentage of cuttings collected from them. Ortets pruned in long- and middle-sized cylindricality grew better, and produced more cuttings because of they were pruned relatively light compared with low-sized table type. These two types of ortets produced 110.5, 237.0, 173.0 cuttings and 85.9, 150.7, 98.0 cuttings respectively on average at ages of 3.5, 5.5, 8.5 years old, which were obviously higher than ortets pruned in low-sized table type with 54.3, 61.4, 43.0 cuttings. Though the long- and middle-sized cylindricality ortets had advantages in growth and cutting production, the effects of controlling maturation and rejuvenating were not as well as expected. Rooting percentages of cuttings taken from ortets of long- and middle-sized types decreased after ortets were 5.5-year-old, then sharply down to 58.3% and 55.3% respectively. Ortets of low-sized table type had lower survival and growth rate, and lower cutting production owing to heavy pruning,but gave good results in delaying aging effect and rejuvenating. Rooting percentage of cuttings collected from low-sized table ortets decreased smoothly after ortets were 7.5 years old, which was two year delay compared with long-sized cylindricality. Rooting percentage of cutting could still be 81.1% when the ortets were 9.5 years old. There was no obvious difference in height growth of two-year-old rooted cuttings derived from different types of ortets when they were younger (2.5-year-old), yet significant difference in height growth could be found between two types of 2-year-old rooted cuttings derived from ortets of low-sized table and long-sized cylindricality type when they were 7.5 years old. For increasing cutting production, ortets should be pruned in long-sized cylindricality type at the primary stage when the orchard was just established,and after years (8 years old) the ortets should be cut back (from the height of 40 cm above ground) to improve rooting ability of cuttings and prolong using time of the orchard.

The genetic effects of general and specific combining ability, male, female, and specific reciprocal cross were analyzed for height, DBH, volume, crown-width, under branch height, crook degree and ratio of branch to shoot in Eucalyptus maidenii. Three quantitative characters, i.e. height, DBH, volume were focus, and their genetic effects were discussed in detail. It was found that the specific reciprocal cross(SRE) was the most important for quantitative characters, then, the male effect(MAL). The general combining ability(GCA) had just less affect height and under branch height, almost zero for the other traits. Specific combining ability(SCA) just affect crook degree and under branch height, but the female effect(FEM) was more important on crown-width, under branch height and ratio of branch to shoot. Two parents were good materials with high value of GCA to the used for establishing next generation seed orchard. Eight combinations were dominant on quantitative characters. It was the best breeding strategy that cross breeding, then superior trees selected from combinations for vegetative propagation, but selection breeding, i.e. establishing seed orchard can not be significantly improved base on the sampling population. Inbreeding depression was very serious in this species.

The study was carried out within Yingde Loblolly Pine Seed Orchard. Trees were planted in 1986, with three classes of planting density, which was 6 m×6 m,8 m×8 m and 10 m×10 m respectively. Randomized Complete Block Design was used with square plot, three replications. Area and tree number of plot was 0.673 hm² and 187, 0.665 hm² and 104, 0.769 hm² and 77 respectively for the three classes of planting density. Clones involved in different classes of planting density were all the same. All there were 20 clones from 9-year-old superior trees in Pengchang Forest Farm, Hubei Province. Because the tree number within plot was different for planting density, the clones were deployed by their remats with equal rate. Measurement was carried out at 7 and 9-year-old and sampling trees at 13-years-old. Studied traits include height, diameter at breast height(DBH) and crown width. From the 7^th to 9^th year, cones were collected and weighed by plot in autumn each year.;The results of 13 years showed that there were significant differences between classes of planting density, for the growth in height, DBH and crown width. The density of 8 m×8 m brought the functions of both the individuals and the population into full play, gave the highest cone yield per unit area. It was followed by the density of 6 m×6 m. The density of 10 m×10 m gave the lowest yield. Cone yield per hectare for the three classes of density, at the age of 13, were 470.98, 422.4 and 307.1 kg respectively. The responding mean yield of single tree was 3.93, 1.88 and 4.11 kg respectively. For the density of 6 m×6 m, trees had grown well until the 7^th year and then came to close gradually(8～10 a) and competition had become violent. On the other hand, for the density of 10 m×10 m, DBH and crown width had the highest growth. At the age of 13, degree of closing was only 0.57, that was most favorable for fruitage. Competition still didn't happen between trees. Our results also revealed that the degree of closing around 0.6 was most favorable for loblolly pine to fruit, with the highest cone yield per unit area. When the degree up to 0.8, it restrain cone yield obviously. For the planting density of 6 m×6 m, roguing should be implemented at the age of 8～9. For the density of 8 m×8 m, time for roguing come to the 10～11^th year. It was concluded that the planting density of 6 m×6 m was suitable for high seed yield in early stage. Meanwhile, the density of 8 m×8 m was suitable for middle to long-term management with high yield. To have both their advantages, the density of 4 m×8 m or 4.5 m×9 m can be used. These two classes of density would give the high cone yield in the early stage,and were convenient for mechanical cultivation.

How to determine the reasonable amount of bamboo shoot dug in a certain bamboo stand is a key problem in the high-yield management of Phyllostachys pubescens. Using the data obtained from 50 plots of Phyllostachys pubescens, the predictive models of bamboo shoot yield and mean D.B.H were built in this paper. Based on the two models, the method of economic threshold was introduced into the research field of bamboo, the new concept of economic threshold of Phyllostachys pubescens ecosystem was put forward, and the economic threshold model of Phyllostachys pubescens ecosystem was founded as follows: M×P sh k∑T-1i 1Δy-ie -iδ+Δy-Te -TδP-{sh}+RMW sh+R(1-k)W sh∑T-s+1i 1Δy-ie -(I+s)δ]P-b +R(1-k)W- sh∑T-1i T-sΔy-ie -TδP-b-F-0∑Ti 1e -iδ. Therefore, this paper not only enriched and developed the research content and application, field of economic threshold, but also provided a scientific basis for the management of Phyllostachys pubescens, and would contribute to realizing its goal of sustainable development and high yield. P-b +R(1-k)W- sh∑T-1i T-sΔy-ie -TδP-b-F-0∑Ti 1e -iδ. Therefore, this paper not only enriched and developed the research content and application, field of economic threshold, but also provided a scientific basis for the management of Phyllostachys pubescens, and would contribute to realizing its goal of sustainable development and high yield.

Correlation analysis was conducted using stem samples collected from Eucalyptus trial stands. A negative linear correlation between the reciprocal of nutrient concentration and the total amount of nutrient uptake in tree stem was observed for the three tested elements, nitrogen, phosphorus and potassium. Based on this linear relationship, the site productivity potential and the nutrient productivity parameter, as well as the site & nutrient effect curves were determined using the measured data with relatively high level of accuracy. The present study provides a new way for approach to the dynamic functional relationship between forest growth and nutrition.

The biomass productivity of different generation plantations of Chinese fir was studied through the investigation of different generation, age and site plantations. The results are as follows:Successive planting results in significant biomass productivity decline of different aged plantations of Chinese fir.As planting generation increases, the stand biomasses of different aged plantations decrease, whereas underground vegetation biomasses increase. Compared to the first generation plantation, the stand biomasses of the second generation and the third generation plantations of 20-year-old decrease by 20.24% and 38.09% respectively. The stand biomass of the third generation plantation of 20-year-old decrease 22.3% compared to the second generation plantation.Moreover, proportions of stem biomass decrease proportions of root biomass increase along with increase of planting generation. Successive planting simulates develop of root and underground vegetation of Chinese fir plantations.

The results proved that Manglietia yuyuanensis was an excellent broadleaved tree species with fast growth rate, high-quality stem form, less diseases and pests and higher wood density.And after slower early growth period, M.yuyuanensis begin to enter a rapid growth phase of stemwood at 10 years old. Individual stemwood of M.yuyuanensis at age 16 was nearly as three times as Chinese-fir, suggesting that interplant with Chinese fir would be a effective way of cultivating high-quality and large-diameter broadleaved wood. Because of marked stem forking, it was important for cultivating high-quality stemwood of M.yuyuanensis to remove or prune sprouts in time. The results indicated that hill slope was a major site factor affecting stemwood growth of M.yuyuanensis in the mountain areas in South China with lower elevation. Gentle slope means deeper soil and better site, resulting in greater stemwood and longer clear bole height. There existed some trend of great height and DBH growth for M.yuyuanensis planting lower position and semi-shade (or semi-sun) aspect.Based on the mechanism of stemwood cultivation, initial planting density and M.yuyuanensis trees per hectare should be reduced properly and higher ratio of Chinese fir to M.yuyuanensis adopted in order to cultivate longer clear bole height and large-diameter broadleaved wood.

Based on the overall on-the-spot survey, combined the typical investigation and fixed position measurement, the coastal protection forest of Pinus thunbergii in Shandong Province was studied. The site conditions of the coastal protection forest were evaluated by means of the quantitative theory I and divided into 11 types, then classified the stand into three height classes by systematic cluster analysis. The results showed that the tree height for class Ⅰis the highest, classⅡis medium and the classⅢ is the lowest. Then based on the comprehensive analysis of the protection maturity and quantitative maturity, the protective maturity period(PMP)of the coastal protection forest for classⅠto Ⅲ were 15～57 a, 14～32 a, and 13～28 a respectively, the regeneration period(RP)were 33～57 a, 23～32 a and 21～28 a respectively, and the reasonable regeneration age(RA)were 33 a, 32 a,and 28 a respectively.

Soil belts of the oxide with REE such as La、Se、Nd、Sm、Eu and Dy were disposed every other 10?m on the bare straightly sloping surface along sloping length (60 m) and sloping degree (6°) in loess plateau. Under the condition of simulating typically erosive rainfall with fainfall intensity (1.0 mm·min^-1) and rainfall duration (40 min), the process of runoff-sediment, sediment discharge of different periods and six kinds of rare earth elements in different positions along the sloping surface were measured and analyzed in the outlet. The results showed that the main place of sediment was 30～50 m from dividing ridge, and the difference of source and distribution about sediment was not obvious along the sloping surface.

strains, isolated from the cadaver of Pantana phyllostachysae infected by Beauveria bassiana,were studied on their colony morphology, growth, sporulation and germination; and their capabilities for controlling Pantana phyllostachysae indoors and outdoors were compared with 4 strains of Beauveria bassiana of Dendrolimus punctatus. The results indicated that the strains had significant difference in their cultural characters, virulence and specialization. The 8 strains were highly virulent to Pantana phyllostachysae and two superior strains, BP4 and BP1, were obtained. The mycelium of the two strains grew fast and could produce large amount of spores with high virulence. The superior strain BP4 was applied in mass production, with 238.7×10⁸·g^-1 sporulation on the average, 96.2% germination and 92.3% efficiency for controlling Pantana phyllostachysae in bamboo forest.

The activities of esterase isoenzyme in Tetranychus viennensis Zacher were tested with Polyacrylamide gel electrophoresis after photo and dark reactivation treated by the chloroform extracts, which was obtained by sohxlet method from the root of Tateges erecta. The results showed that both photo and dark treated group with the chloroform extracts could inhibit the activities of esterase isoenzyme. With the increase in the concentration of the extracts, the number of the isoenzyme lanes, the OD value and the peaks area of the gel's scanning curves reduced gradually. The inhibition potential of photo treated group was obviously significant higher than that of the dark treated group. Neither light group nor dark group, there was not any new isoenzyme band coming out after treated by the extracts. Thus, it seems to be that the chloroform extracts of the root of Tateges erecta have some inhibiting activities to the esterase isoenzyme in Tetranychus viennensis Zacher after treated with light.

Tateges erecta is an useful natural plant pesticide according to the former reports.In this paper,the effects on several enzyme systems about extracts of Tateges erecta against Tetranychus viennensis Zacher were studied.The results showed that the extracts of Tateges erecta had hgih effect on Tetranychus viennensis Zacher.Different from that of the dark treated group,the activities of protease,GSTs and esterase isozyme could be strongly inhibited in light treated group.The result indicated that the extract of Tateges erecta possessed high photo-activity.

Proteins in healthy and infected leaves of diseased trees and healthy leaves of healthy trees of Paulownia tomentosa Steud and P.Fortunei(Seem)Hemsl,which were on the same direction and at the same age,related to Paulownia witche's broom were studied by SDS-PAGE and 2-D-PAGE.The results indicated that there existed difference among healthy and infected leaves of diseased trees and healthy tree leaves of P.tomentosa and P.Fortunei trees in protein quantity and quality,in which obvious protein numbers were 22,20,17 and 27,21,22 with SDS-PAGE respectively.Moreover,the changes of proteins in healthy and infected leaves of diseased trees and healthy tree leaves of P.tomentosa had similarity to that of P.Fortunei on basis of 2-D-PAGE.That is,the protein(pI 6.8,MW24KD)existed in healthy tree leaves and infected-healthy leaves of diseased trees disappeared in diseased leaves.This protein change might be considered to have relationship with Paulownia witche's broom.

Based on the models of tracheid and ray cell, and by means of computer sampling simulation, the longitudinal elastic moduli were evaluated with corresponding equations and calculating methods for juvenile and mature wood from plantation Chinese Fir(Cunninghamia lanceolata) and Masson Pine (Pinus massoniana).There was a great agreement between estimated values and measured values for the elastic moduli of two species. This research report presented a practical way to study on the longitudinal elastic modulus of wood from above two species and ones with similar structure, and it was useful to develop the theory on the mechanical behaviors of softwoods.Variations of the longitudinal elastic modulus were estimated for specimens from Chinese Fir and Masson Pine when latewood percentage and structural parameters of tracheid were changed in the specimens. Results showed that the longitudinal elastic moduli increased with increasing of latewood percentage, tracheid length,and thickness of cell wall, and it decreased with increasing of radial and tangential diameter of tracheid. Finding and conclusion in this paper can be used in the practice to improve the wood properties of softwood through using the modern biological technology.

In this paper, the problem of nonlinear systems robust tracing containing uncertain diathesis, which abstracted from Computer Integrated Manufacturing Systems (CIMS) in wood industry was discussed. Where, unknown parameters taken value from a compact set Ω are time-varying. Furthermore, self-tuning controller of a robust tracking problem is given when unknown parameters appear both linear and nonlinear style.

Deterioration of culms of Phyllostachys pubescens after the treatment of ultraviolet irradiation was investigated by means of a scanning electron microscope (SEM), light microscope and colorimeter. SEM observation on the cross sections of the bamboo showed that the deterioration in the fibers started in inter-layers of secondary walls followed by the cell corners and the middle lamellae. While the deterioration in the parenchyma cells began from the cell corners followed by the middle lamellae. Consequently, all the cell walls were eroded. In terms of the colour reaction after 40 days of UV irradiation on the cross sections of bamboo surface, it was further determined that the deterioration reached a depth of 590 μm in the parenchyma and 146 μm in fiber from the surface. In addition, this study noticed that there exited sharp difference in colour and brightness after the treatment with the UV irradiation along the different directions. Finally, the mechanism of causing the structural changes was discussed as well.

Making use of equipments,three-line track rope and saving labour hoist ropeway was creatively remade.The ropeway was designed by using catenary theory,for the accomplishment of assignment of heavy rib arc aqueduct for the water conservancy department.It rushed out a new way for the application and development of forestry ropeway.The hoist ropeway had its advantage and made it especially suitable in the hoist of great prefabricated components or heavy equipments in the engineering construction of department,such as mountain area water and electricity,water conservancy and traffic and building.

The definition of forest is the basis of defining afforestation, reforestation and defforestation (ARD) activities and has close relations with the carbon accounting for the land use, land use change and forestry (LULUCF) sector. Definitions of ARD can significantly impact accounted carbon emission or removal by ARD under the Kyoto Protocol 3.3. Based on the information and discussions on the Expert Meeting on Harmonizing Forest-related Definitions for Use by Various Stakeholders and two expert meeting on LULUCF Good Practice Guidance, national and international definitions of forest and ARD were investigated in the paper, the impacts of forest and ARD definitions on carbon accounting were discussed and key issues in carbon accounting were also addressed.

Incubation experiment and field investigation on soil microbial biomass dynamics in agroforestry system in coastal saline soil, which impacted by litter decomposition process of Populus and Metasequoia glyptostroboides, were carried out in this study. It was showed that the litter of Populus was more favorable to soil microbial biomass increase, whereas litter of M. glyptostroboides was less favorable to soil microbial biomass increase, but the microbial biomass N content associated with litter decomposition of M. glyptostroboides was higher than that of Populus, and litter of M. glyptostroboides was easier to be accumulated in the soil. There was a positive interaction for microbial biomass increase when M. glyptostroboides leaves mixed with Populus leaves during decomposition. According to soil microbial parameters, such as ratio of microbial biomass N and total N, metabolic quotient (qCO₂) from field investigation, it was also proved that although the soil organic content under forest increased, the soil salinity content had not decreased significantly, and the qCO₂ was still high. This may suggest that the increase of organic matter through agroforesty practice did not efficiently mitigate the environmental stress for soil microbes. Therefore, in the study soil, it is still necessary to adopt other measures to improve site conditions.

The transpiration characteristics of Acanthopanax brachypus and their relationship with the ecological factors of photosynthetic active radiation (PAR), air temperature and air relative humidity etc, were studied in two habitats of open land and under-forest in this paper. The transpiration curve of Acanthopanax brachypus in two habitats belonged to single-peak type. The maximum transpiration rate and diurnal average transpiration rate of Acanthopanax brachypus on open land were higher than those in forest. PAR was the most important ecological factor affecting the transpiration rate in forest. On open land, air temperature and relative humidity had significant effects on the transpiration rate; PAR had a little effect on transpiration rate. Water use efficiency on open land was higher than that in forest. Based on the preliminary analysis of water physiological ecology of Acanthopanax brachypus, it was concluded that open land with better water conditions was suitable for its growth.

Five controlled crosses of Eucalyptus urophylla S.T.Blake×E.tereticornis Smith were used for RAPD analysis on DNA polymorphism and heterozygosity of the seven parental clones.A total of 58 fragments were amplified with 9 single arbitrarily chosen primers,and 42 fragments(72.4%) were scored as polymorphic among the parents.The genetic distance (GD) between parents was calculated with RAPD data matrix.High levels of heterozygosity were revealed in the parents studied,with an average 28.0%,but the percentage of heterozygous loci varied with parent from 16.2% to 39.5%.The implications for material selection in genetic linkage map construction were discussed.

Salt-induced/repressed genes were isolated at the transciption level in P.euphratica using subtractive hybridization technique.About 40 cDNA fragments were obtained with polyacrylamide gel electrophoresis from +6/-6 to +8/-8 cDNA hybridization cycles,which will be used for screen and cloning salt-tolerant genes of P.eupharatica and studying the mechanism of salt-tolerant.

A new pathogen Nosema glabripennis Zhang parasiting the longhorned beetle Anoplophora glabripennis. According to the field investigation, about 2.8% of the real pathogens for naturally dead longhorned beetles were microsporidiums and the other pathogens were mostly saprophytic or other parasitic organisms, which parasitized the beetles after infection by the microsporidium. The results of bioassey showed that the mortality of the longhorned beetle larvae was 27.4%. The microsporidium possesses the ability of vertical dissemination and was hopeful to be an effective natural organism to control the beetles.

Elastic modulus of the 17 and 50 loblolly clones were measured by DSCM . The result showed E_L, E_T and E_R of the 17 loblolly clone were 6 110, 1 207, 1 576 Mpa, respectively. Those of the 50 loblolly clone, however, were 5 965, 1 308, 1 606 Mpa, respectively. In addition, the method of DSCM for the compression elastic modulus of loblolly was right and proved by resistance strain gages. The error was 1%～7%. DSCM have some virtues, such as simple optical setup, convenient measurement, etc.