Robinia pseudoacacia is one of the major planting tree species in the Shaanxi Loess Plateau.Changwu county and Ansai County lie in the semihumid and semiarid region of the area,respectively.In this paper,the fine root vertical distributions of R.pseudoacacia growing at the two counties were studied,using soil auger method.The results showed that the fine root vertical distribution had distinct differences in these two regions.The mean depth of fine root vertical distribution was 250 cm in Ansai County,and only 200 cm in Changwu County.The average fine root surface area(cm²·dm^-3)on shady and sunny slope of Ansai County was 5.06 and 8.29 times over the value of Changwu County,respectively.Both on shady and sunny slope of the two counties,the maximum value of fine root surface area presented soil surface(0～20 cm)and then decrease slowly in Ansai County.However,the maximum value appeared on 60 cm in Changwu County.About 80 percent fine root of R.pseudoacacia distributed in 0～150 cm soil layer in Ansai County,and in 0～100 cm in Changwu County.In addition,the fine root was richer on shady slope than sunny slope both in Ansai and Changwu County.The fine root vertical distribution characteristics was significantly related to soil water,which was a key factor to influence fine root distribution.The model S=Ah^B(C+Dh+Eh²+Fh³)can well described R.pseudoacacia's fine root vertical distribution in these two regions,the fit decide coefficient(R²)more than 0.94 in Ansai and more than 0.80 in Changwu County.The research of R.pseudoacacia's fine root vertical distribution under different soil water environment will help to further explore the relationship between fine root system and soil water and the reason of soil drification in the Leoss Plateau.

Eremochloa ophiuroides was used to study the effects of acid rain stress on chlorophyll fluorescence characteristics.The results showed that maximal photochemical efficiency of PSⅡ(F_v/F_m),potential activity of PSⅡ(F_v/F₀),photochemical quenching(q_P),quantum yield of PSⅡ electron transport(Φ_PSⅡ),electron transport rate of PSⅡ(ETR),non-photochemical quenching(NPQ)in leaves were reduced after 6 h stress with acid rain.The decline of above parameters in treatment with pH 2.5 were faster and larger than that with pH3.0.F_v/F_m、F_v/F₀、q_P、Ф_PSⅡ、ETR、NPQ in treatment began to be gradually recovered after the treatment ended for 24 h,and up to the level of control after the treatment ended for 48 h.The results also demonstrated the potential use of this fast and noninvasive techniques——chlorophyll fluorescence to screen for different acid rain tolerant genotypes and to detect the physiological response of grasses to different environmental factors.

Concentration and distribution characteristics of PAHs in soil between a Cinnamomum camphora stand and a bare land were studied,and PAHs concentration levels in two kinds of soil were evaluated.The results showed PAHs mainly accumulated in 0～30 cm soil depth in two lands and apparently decreased with the increasing of soil depth.Every soil layer was dominated by high molecular weight PAHs,So PAHs mainly result from combustion.The PAHs concentration is 1.1 times as much in the C.camphora forest land as in the bare land.In addition,the evaluation also implied PAHs concentrations in the bare land were higher than those in the C.camphora forest land.PAHs in the C.camphora forest land and the bare land exceed standard by 5 kinds and 8 kinds,respectively.

In order to understand the species diversity and ecological characteristics of seed vines in Hunan and Hubei Provinces,Origin of taxonomic units,climbing mechanics,breeding system and life habits of vines were studied.The results showed:There are 784 seed vine species,belonging to 159 genera and 60 families,which account for 11.1%,10.8% and 29.7% of the whole seed plant flora in this study area,respectively.The seed vine flora composes mainly of small families and genera in this study area,the number of families(genera)with 1～10 vine species account for 68.3%(89.9%)of the total families(genera).Although the seed vine species are included in many families,the majority belongs to relatively few families.Thus 64.8% of the 784 seed vine species only belong to 11 families(Vitaceae,Actinidiaceae,Papilionaceae,Ranunculaceae,Rosaceae and so on).The seed vine climbing mechanics are divided into 5 main types and 12 subtypes,among which twining account for 48.7%,curling 23.2%,hooking 16.5%,adhering 6.0%,mixed 5.6%.In the seed vine sexual system,the bisexual flower account for 67.3%,the polygamous flower 5.1%,the dioecism 20%,and the monoecism 7.5%.

The photosynthetic characteristics and chlorophyll fluorescence characteristics of introduced three almond(Amygdalus communis)cultivars 3^#、4^# and 7^# were studied.The curves of diurnal variation of net photosynthetic rate(P_n)in leaves of almond showed two peaks,occurring at 10:00 and 16:00 respectively.Midday depression of P_n(10:00—15:00)was found in leaves of almond.P_n of leaves of 4^# and 7^# almond was significantly higher than that of 3^# during 10:00—15:00.Some physioecological parameters showed significant difference among different cultivars.The light compensation and saturation points of P_n in 4^# leaves were higher than those in 3^# and 7^#,25.82 μmol·m^-2s^-1 and 1 206 μmol·m^-2s^-1 respectively.The CO₂ compensation and saturation points of P_n in 4^# leaves were higher than those in 3^# and 7^#.P_n was increased linearly with the increase of CO₂ concentration below the CO₂ saturation point,thus increasing CO₂ concentration could improve productivity greatly.And the results of diurnal variations of chlorophyll fluorescence showed that F_v/F_m and q_P of 4^# and 7^# were higher than 3^#,and F_v/F_m restored very fast after noon.The leaves of 4^# and 7^# not only could absorb the light energy more effectively,but also had higher PSⅡa ctivity and light energy transform efficiency,which could turn light energy absorbed into chemical energy effectively,then the transmit speed of electrons was improved.So more ATP and NADPH were formed,which could offer abundant energy and reduction ability for CO₂ assimilation.

The Na⁺/H⁺ antiporter is a ubiquitous membrane protein gene family of bacteria, plants and mammals. In Arabidopsis thaliana, six NHX isoforms have been identified to date and some of which have a major function in response to NaCl. The Populus NHX₁ and NHX₆ cDNA isolation was performed by underlying the electronic cloning technique, based on the Populus EST databases and P. trichocarpa genome sequence using AtNHX₁ and AtNHX₆ nucleotide cDNA sequence information. Two cDNA clones encoding NHX were isolated from the cDNA prepared from cambial zone of Populus tomentosa by the RT-PCR method. These two cDNAs are 1 635 bp and 1 709 bp in length with corresponding open reading frames (ORFs) which are capable of encoding the protein of 544 and 526 amino acids (aa), respectively. The deduced aa sequence of the PtNHX₁ and PtNHX₆ (GenBank accession number AY660749 and AY832912) proteins shares 79%,76%,69%, 74% and 82%,82%, 27%,26% identity with the other recently isolated A. thaliana, Oryza sativa, Triticum aestivum and Zea mays NHX₁ and NHX₆, respectively. When poplar genomic DNA was digested with selected restriction enzymes and then analysed on a Southern blot, we found one to four bands that were labelled, suggesting a low-copy gene (or a few highly homologous genes) within the poplar genome. Tissue differential expression indicated that PtNHX₁ and PtNHX₆ transcripts have their mRNA products in roots, stems and leaves, but have some differences in PtNHX₁ and PtNHX₆ gene. As for PtNHX₁, it was expressed predominantly in roots, cambium, immature xylem, young leaf and mature leaf, with some expression in the phloem and mature xylem zone of the stem. The PtNHX₆ transcripts are the most abundant mRNA products in roots, young and mature leaf, and a low-abundance was detected in phloem, cambium and xylem. To confirm the possible regulation of PtNHX₁ and PtNHX₆ gene expression by NaCl, the RT-PCR detection of the expression abundance of the PtNHX₁ and PtNHX₆ genes was performed at different NaCl concentration (from 100 to 600 mmol·L^-1) after exposure to the salt treatment. The results showed that PtNHX₁ and PtNHX₆ message levels were increased for the NaCl concentration of up to 400 mmol·L^-1 but declined with the concentration of more than 400 mmol·L^-1 and this expression pattern matched the ABA content detected in the leaves. The data suggest that PtNHX₁ and PtNHX₆ are induced by salt stress.

A cDNA library of male floral buds of Populus deltoides through SMART(the Switch Mechanism At the 5' end of RNA Templates)technique was constructed.4 200 clones randomly selected from the cDNA library were sequenced and 3 092 raw sequences were obtained.3 087 valid ESTs were generated after the size of inserts shorter than 150 bp and the contaminants were removed.The average length of the cDNA was 515 bp.A total of 416 clusters were formed after assembly of the 3 087 ESTs,and 451 contigs and 1 104 singletons were obtained.1 015 ESTs with known or unknown function were identified by BlastN searched against the NCBI non_redundant nucleotide databases,540 ESTs had no significant similarity to any protein or DNA sequence in the databases.The present ESTs provide a valuable resource for further research on the flower development of higher plants.

Embryo rescue of interspecific hybrids between wild diploid species Dendranthema lavandulifolium,D.nankingense,D.dichrum and cultivated species D.morifolium was studied in this paper.The results indicated that the genotypes and the days of embryo rescue were important factors.13～18 days after pollination were the suitable time for embryo rescue.Medium had little effect on ovary culture.Beneficial proportion of hormones was BA 2.0 mg·L^-1+NAA 2.0 mg·L^-1.The rescue result was better when wild diploid species used as female parents than as male parents.RAPD and morphological analysis showed that they were real hybrids.

The effects of five different site management treatments on productivity of 6-year-old,second rotation Chinese Fir(Cunninghamia lanceolata)plantations planted after harvesting a 29-year-old,first rotation Chinese Fir plantation in Xiayang State Forest Farm,Nanping,Fujian Province,were studied.The results showed that the Chinese Fir stand grew the best on the double slash treatment(BL₃),followed by the whole tree harvest treatment(BL₁)and slash burning treatment(SB),and the poorest on the no slash burning treatment(BL₂)and the no slash treatment(BL₀).The site index of the second rotation Chinese Fir plantations in the BL₃ and BL₀ treatments increased by 0.56 and 0.27,respectively,compared with the first rotation,and decreased in the rest of the 3 treatments.Compared with the first rotation,site index of the second rotation treated with BL₁,SB and BL₂ treatments decreased by 0.39,0.45 and 0.63,respectively.Differences between the treatments were not statistically significant.

Experiments were conducted with potted jujube to study the changing of NR activity in different organs and periods as well as the effect of different nitrogen forms on NR activity.The result showed:leaf was the main organ which assimilated NO^-₃.The new-leaf has the highest NR activity,then was the mid-leaf.The activity of down-leaf was the lowest.NR activity of fine-root was higher than other roots but lower than leaves,the activity of absorption roots could not be observed.Further,the diurnal variation of NR activity in vivo showed a peak curve and maximal NR activity appeared at about 11:00 or so.The change of seasons showed NR activity in leaves was higher in August comparing with other seasons and NR activity of roots appeared three peak in Jun,Aug and Oct.In addition,the effect of different nitrogen forms on NR activity indicated a peak appeared after 4 h daubing leaves with 40 mmol·L^-1 KNO₃.NR activity in vivo could be raised by lower concentration of KNO₃(<80 mmol·L^-1)and be increased no more with higner concentration of KNO₃(>80 mmol·L^-1).NR activity could also be improved by daubing urea.In addition,NR activity was not significant effected after daubing Glu or Gln,however,was remarkablely decreased by Gly.Fertilization in soil showed urea could maintain the higher NR activity in leaves and increased the ability of assimilation NO^-₃.

A mutualism of ants with Codariocalyx motorius has been formed through a long interrelationship and co-evolution.The effectiveness of ants in removing seed of Codariocalyx motorius has been studied together with its effects on seed predation by rodents in Simao and Xishuangbanna of Yunnan Province,China.The results show that dispersing distances of seed removed from their mother plants by ants are not very great,with averages of 0.93～2.53 m,but exceed the shooting distance attained by seeds themselves.Each of ants,which are leading remover of C.motorius seed,has its own peak in the removing distance curve.When ants can not access the seeds,the predating ratios of C.motorius seed by rodents are 28.3% and 16.5% respectively in Jinggu and Menglun,in contrast with the high rates(77%,daily and 35.7%,night)of dispersal by ants when rodents can not predate the seeds.The shooting time of mature seed falls into the ants' periods of activity,and therefore ants can effectively remove the seed before rodents reach it.The experiments show that coexistence of C.motorius with ants is beneficial to protection and dispersal of the seed,as well as reduction of seed loss by rodents,and so promotes the development of the plant population.

The fungi of genus Botryosphaeria,genus Coniothyrium and genus Dothichiza can cause huge disaster in forestry and man-made poplar forestry in China.Six micro-satellites primers [(GT)n,(CGA)n,(CCA)n,(GAA)n,(CAA)n,(GA)n] and one mini-satellites primer M13 used to identification the molecular relationship of those three genus.All 42 tested isolated isolates are clustered into 4 groups,22 Botryosphaeria isolates and 6 Dothiorella isolates are disperse in this 4 groups,but group I,Ⅱ and IV formed only by the Botryosphaeria and Dothiorella isolates.However,the other 6 Botryosphaeria dothidea isolates and 4 Botryosphaeria berengeriana isolates formed the subgroup of group Ⅲ,6 Coniothyrium isolates and 2 Dothichiza isolates only occurred in the subgroup of group Ⅲ.The results of RAMs-PCR showed that the Botryosphaeria dothidea or Dothiorella isolates which identification by anamorph characters were not a monophyletic group.The putative pathogenic fungus of apple stem rot and ring spot,B.berengeriana and its physiological form could not formed a clear cluster branch separately and which merging with some B.dothidea isolates in a complex group.This result illustrated that Botryosphaeria berengeriana is very similarly with some B.dothidea isolates.The result also illustrated a close relationship between genus Coniothyrium and Dothichiza.

In the study,the dynamics of lignolytic and cellulolytic enzymes,viz.laccase,lignin peroxidase(LiP),manganese peroxidase(MnP),carboxymethylcellulase(CMCase)and filter paper activity(FPA)secreted by six soil-inhabiting deuteromycetes,were investigated systematically during the decomposition of Pinus massoniana needle litter in solid state fermentation(SSF).The six deuteromycetes exhibited varied profiles of enzymes secretion and caused different loss in TOM and decomposing rate.Pestalotiopsis sp.produced the highest laccase activity and caused the highest loss in TOM;Alternaria sp.produced the highest MnP activity;the highest CMCase and FPA activities were detected in strain Pestalotiopsis sp.The process of decomposition was closely correlated to the changes of enzyme activities.The early-stage decomposition primarily depended on activities of cellulolytic enzymes.While later-stage decomposition depended on the lignolytic enzymes,which acted synergistically with cellulase.According to these results,fungi could be divided into two functional groups:group 1 were cellulose decomposers,including Alternaria sp.,Penicillium sp.,Cephalosporium sp.and Tricherderma sp.,group 2 were decomposers of lignocellulose,including Pestalotia sp.and Aspergillus fumigatus.Meanwhile,we find Pestalotiopsis sp.could produce an appreciable high level of laccase.

Fuel type is a basic concept to describe the state of fuel,and it is usually used as a basic input for the fire behavior model of the forest fire danger rating system.The paper uses the land cover map and Landsat TM imagery of Beijing to make the fuel map by using supervised classification.Fuel type maps account for structural characteristics of vegetation related to fire behaviour and fire propagation.The results classify the vegetation into six fuel types:O_1 grass,O_2 grass(high coverage),S_1 shrub,S_2 young plantation,C_1 conifer forest,M_1 mixed wood and B_1 broad_leaf forest.Due to the resolution limit of TM imagery,it is difficult to distinguish the forest variety in vertical structure.The results can be used in the forest fire danger rating system,but there is a need for further classification for the fuel with the flammability,vertical structure and distribution in order to make the fire behavior prediction.The paper also discusses the current methods and development of fuel classification and mapping.

Based on the field investigation,sampling and the laboratory experiment,the ignition moisture content and spread moisture content of 30 tree and bush species leaves were analyzed by applying factor analysis and cluster analysis.The ordering of combustibility and spread degree of those fuels were given out.The result shows that those 11 species of Populus davidiana,Acer saccharum,Rhamnus davurica,Acanthopanax senticosus,Betula nigra,Deutzia amurensis,Gleditsia japonica,Ribes mandshuricum,Sambucus uilliamsii,Philadelphus schrenki,Catalpa ovata have relatively higher fire resistant ability.While those 10 specie of Caragana arborescens,Malus baccata,Hemiptelea davidii,Euonymus alatus,Pterocarya stenoptera,Viburum burejaeticum,Pyrus ussuriensis,Crataegus pinnatifida,Euonymus maackii,Pinus tabulaeformis have relatively lower fire resistant ability.Those results can have a help to the selection of fire-resistant species.

To improve the permeability of larch wood,high intensive microwave irradiation was applied to wood.The microwave treated and untreated larch wood was water-impregnated by pressure at the same conditions,and then the water absorption ratio(WAR)of the microwave-treated wood samples and the untreated(control)was calculated to evaluate the permeability of the wood.The relationship was discussed between the permeability of larch wood and the conditions of microwave treating process such as the initial moisture content(MC)of wood,the inner temperature of treated wood,microwave power and the time of microwave treatment.The results showed that by controlling the microwave treating conditions properly,the permeability of larch wood can be improved.The proper range of the initial MC of wood was from 25% to 60% for intensive microwave treatment in the conditions of this paper.The proper microwave power is related to the initial MC of the wood,and it was 9～24 kW in this paper.While the proper time of microwave treatment is determined by the initial MC and the microwave treating time applied to the wood.When the initial MC of larch wood was about 30%,being irradiated for 55 s by the microwave power of 9.23 kW,or being irradiated for 25 s by the microwave power of 20～24 kW,the WAR of the microwave-treated larch wood was more than 200% of the untreated,indicating the permeability of larch wood was improved remarkably.The mechanism of permeability improvement of larch wood by intensive microwave irradiation was discussed.As intensive microwave was applied to larch wood,the water inside the wood cell boiled rapidly,forming vapor.When the vapor pressure increased high enough,it broke down the weaker part of the wood cell and formed tiny invisible cracks in the cell wall,forming new channels for water and vapor going through the cells,and the permeability of larch wood was thus improved.Increasing microwave power accelerated the formation of the tiny cracks in the cell wall and shortened the treatment time,but excessive microwave intensity or too long treatment time might result in surface checking and inner checking of wood.

The stress of surface layer of small-diameter Asian White Birch(Betula platyphylla)timber with consecution-heat and intermittent-heating(intermittent 2 h and intermittent 6 h)was discussed.The results showed that the change of tress of surface layer with three kinds of heating methods were in a similar way.However,during either prophase drying or metaphase drying,the stress with intermittent-heating was smaller than that with consecution-heat,the stress was least with intermittent 6 h.The drying stress was loosed during intermittent,intermittent time more long,the effect of loosen more remarkable.At the same moisture content level,the stress of surface layer of tangential timber was larger than that of radial timber.

Because bamboo absorbs water slowly,the softening time of bamboo blocks by this routine softening method lasts long.In order to improve bamboo softening effect and effeciecy quickly,softening treatment technology at high temperature was adopted.Effect of softening treatment of bamboo at 120 ℃ for 30 min was studied in this paper.The results of modulus of elasticity(MOE)of bamboo showed that the MOE of bamboo strip after softening treatment for 30 min at 120 ℃ was decreased from 8 912 Mpa to 6 417 Mpa which meant that plasticity of bamboo was increased greatly.The results of dynamic mechanical analysis(DMA)showed that glass transition temperature(T_g)of no softening treatment bamboo was 120 ℃,while T_g of softening treatment bamboo at 120 ℃ for 30 min was 88 ℃,T_g of softening treatment bamboo at 120 ℃ for 30 min decreased 26.7% compared with that of no softening treatment bamboo.The results of hardness showed that the hardness of surface near outer part of bamboo and surface near inner part of bamboo after softening treatment for 30 min at 120 ℃ was decreased with 42.0% and 54.6% respectivly compared with no softening treatment bamboo.The results of thickness deviation and lathe check on the loose side of veneer showed that surface quantity of bamboo veneer can be guaranteed after softened at 120 ℃ for 30 min.

In the paper,introduced development of mechanization forestation for tree planting in our country and other's,indicated the emphases of research about the digging machine for tree planting in homeland.And then,analyzed emphatically the establishment of torsional vibration model of auger bit axis,at the same time,analyzed systematically the interaction force between bottom of auger-bit principal axis and soil,auger-bit principal axis gravity and inertia,gave the dynamical stochastic boundary condition and initial condition by the spatial kinematics,the theory of mechanization vibration and the principle of elastic dynamics.The results can provide new theoretic basis for the dynamic characteristic simulation of auger-bit and whole machine dynamic characteristic research,rationally forecasting and controlling movement rule of auger-bit,improving the dynamic characteristic of auger-bit,enhancing work efficiency of auger-bit and improving design method of auger-bit.

In this paper,the saw-timber's analytical model was applied.Considering the bending curvature,the optimal design for improving recovery ratio was applied to making bending wood and the mathematical model was initialized.Because this saw-timber's model is the optimal models based on continue analytical saw-timber model,which precise is better than traditional way's.The objective function is from continue function,especially with the analysis of continue function,every parameter's effect to optimal design is worked out,and these parameters are superior for initialing the optimal objective function and considering the best answer to the function with optimal designing,which is complied with in the industrialization of bending wood.

Being a necessary direction of modern forestry development,nonpublic owned forestry will become a better approach to social investment in forestry industry.This paper reveals the major problems in forestry management system,such as failure in protection of nonpublic owned forest property right,restriction of development by harvesting quota,incomplete regulation of forest land application,heavy forestry taxation,and incompletion in the regulation of forestry finance.A set of corresponding solutions is proposed in this paper,which includes:a)enhancing the protection of property right,b)adjusting harvesting quota,c)improving in regulation of forest land utilization,d)alleviating taxation in forestry industry,and,e)implementing a newly developed regulation of investment in forestry industry.

Many examples have proved that exotic trees can produce great ecological,economic and social benefits.However,biological invasion of exotic trees has drawn increasing attention.The potential risk of biological invasion of exotic trees should not be overlooked in any tree introduction program.Correct understanding of the concepts of exotics,invasiveness of exotic trees and risk of invasion is needed to develop sound strategies for preventing and controlling potential biological invasion of exotic trees.Many studies have been carried out in many countries to assess invasiveness of exotic plants,patterns of biological invasion and consequences of invasion,to predict potential invasion risk and to develop strategies for prevention and control of invasive alien plants.However,much fewer studies were concentrated on exotic tree species due to scarce literature available on invasive trees.Similar to alien invasive plants,invasive exotic trees can have negative impacts in multiple aspects on environment,most severely on biodiversity and ecosystem functions,which are usually in large-scale,long term and irreversible.Based on literature review of 1 211 exotic tree species,443 species are invasive or potentially invasive,accounting for 39% of the total number.282 invasive tree species have been used in forestry operations.Invasion usually occurs in steps of introduction,establishment and rapid spread.Risk assessment should be conducted for any future tree introduction program.Trees have much longer life cycle compared to other types of biological organisms such as insects and grasses,therefore the time-lag of invasion is long,making it more difficult to predict the potential of invasion.Moreover,most of exotic trees have great values for its timber and can be utilized once found to be invasive.These unique features of exotic trees should be considered in developing strategies for invasion control.Criteria and indicators should be developed to assess invasiveness and ecological impacts of exotic trees.Risk assessment of biological invasion should be conducted prior to any tree introduction.Invasiveness can be assessed according to the biological characteristics of alien tree species.However,ecological impacts can only be assessed through long-term monitoring and evaluation.

Virtual trees are models that describe the growth and development of a tree in 3D space by computer simulation.The study of virtual plants has been more and more popular in botany,agriculture,forestry,environmental sciences and computer.Growth modelling and visualization techniques are essential parts of virtual plants.Growth models of virtual trees include morphological structural models,functional models and functional-structural models.Functional-structural models may simulate the interaction between trees and its environment,whose outputs are 3D structure of trees.Therefore,functional-structural models are more close to realistic tree growth process and lead the trend of tree growth modelling.One of the major difficulties in tree visualization is the contradiction of between computer time and memory occupation and tree morphological structure complexity.Specific features different from normal objects for visualization cover self-similarity,ramification,branch bending,phototaxy,smoothly and un-smoothly blending branching etc.Tree visualization software is based on either pure graphics or functional-structural models,which has been applied in games,commerce,computer-assistant landscape design and forestry education,research and practice.Further work should be done in the collection and management of tree architecture data,the development of functional-structural models,the visualization techniques and forestry-oriented application.

Air and shallow soil temperature in forest site are important factors impacting carbon cycle and plant physiology of the ecosystem.It is an effective method to estimating these temperatures by the recordings at neighboring meteorological station.The estimations will fill the gap of micrometeorological measurements in forest area.An empirical model to estimate the air temperature in the crown and soil temperature at 5 and 20 cm depth in the mixed forest of broad_leaved and Korean_pine was established,according to the recordings at adjacent meteorological station.The effects of seasons and snow coverage were taken into account in model establishment.The results showed that estimations were well accordance with the measurements.

Using 608 Robinia pseudoacacia materials gathered from 13 provinces in China,7 allozyme were electrophoreticlly analyzed in order to detect the genetic diversity of Robinia pseudoacacia population in China.The desirable 7 allozym systems were Amy,Fe,Lap,Idh,Mdh,6-Pgd,Skd.The Ae ranged from 1.592 8～2.761 2.The Ho ranged from 0.187 6～ 0.676 6.The F varied from-0.151 2～0.496 8.The process of making starch gel,model of electrophoretic zymograms and the experience in describing the locus and allele were discussed in detail in this article.As well as the Robinia pseudoacacia population in America and Europe,the Robinia pseudoacacia genetic diversity in China is also high.The results indicated that new Robinia pseudoacacia ecotypes were formed in China under different ecological environment,also,it seemed impossible for gene drift occur in Robinia pseudoacacia population in China.Compared with other genetic markers,allozyme marker still has its unique advantages in detecting population genetic diversity.

Eleven microsatellite(SSR)markers were used to evaluate the genetic diversity and paternal parents of a seed orchard for Pinus massoniana planted at Wuyi Forest Farm,Fujian Province.The seed orchard contains 286 open-pollinated progenies derived from 129 candidate paternal clones and three maternal trees.Both the parental and progeny populations displayed high genetic diversity(h),with the estimated h values of 0.543 8 and 0.455 6,respectively.Paternal clones contributed differently to the progeny;only 5.3%～15.8% clones contributed 27.08%～48.96% pollen.More strikingly,one paternal clone contributed 10% and 17% pollen,respectively,to two maternal trees.It was found that the mating compatibility of a clone was not related to its origin.There was no significant influence of the physical location of a clone on the amount of paternal constituent and genetic diversity.The rate of contamination by pollen outside the seed orchard was as high as 9.44%.No selfing progeny was observed,suggesting that selfing depression will not be an issue in the seed orchard of P.massoniana.

Rooting characteristics of forest trees is an important trait both for silviculture and also for genetic improvement,but its progress which was made on its improvement was rather small due to the complexity and heavy work for rooting traits measurement.Fractal theory provided a new idea and also a method to deal with such complicated traits.The rooting characteristics based on cuttings of 46 poplar clones were investigated,poplar cuttings were cultivated in two kinds of medium,perlite and fresh water.Pictures were took for each cutting with a digit camera and then edited with Photoshop 6.0,Fractal dimensions were obtained for each picture by the software(FDC1.0).For the two rooting traits(length,dry mass)investigated,there were significant differences existed among clones.The variation ranges of fractal dimension of cuttings were 1.173～1.533 for 46 clones cultivated in perlite,and 1.513～1.814 for 34 clones cultivated in water.A significant positive correlation was found between fractal dimension and dry mass of roots,thus,fractal dimension might be a substitutive index for rooting characteristics.In general,the more the cutting roots,the bigger the fractal dimension.

Antennae surface structure and morphological characters of male and female Dendroctonus armandi were observed with scanning electron microscope(SEM).The results indicated that there were not obvious differences between structure and morphology of male and female.Most of the sensilla were distributed on the club of the antenna that occupied 90.3%,while only 7.4% and 2.3% on scape and funicle.All of the sensilla could be categorized 5 types:sensilla trichodea,sensilla chaeticum,zigzag sensilla,sensilla basiconicum,and bud-shaped sensilla,of which sensilla trichodea and sensilla basiconicum were dominant sensilla types and mainly distributed on the club,zigzag sensilla were secondly number and mainly distributed on the scape and funicle,and only a few on the funicle,while sensilla basiconicum and bud-shaped sensilla were the least number,only 1～3.Sensilla basiconicum distributed on connection between the scape and the first funicle,but bud shape sensilla mainly distributed on the end of scape or the tip of club.