The chemistry of rainfall,throughfall and stemflow was measured continuously for three years (1994～1996) in two Chinese fir forests with different distances from pollution source in Nanping,Fujian. Precipitation chemistry was dramatically altered upon passage through forest canopies at both sites.The pH values in throughfall decreased slightly,but EC values were significantly higher because of its higher ion concentrations than in rainfall. Stemflow showed extremely acidification and nutrient enrichment.Acidity of rainfall and throughfall showed some seasonal patterns,generally with minimal pH values in summer,maximal in winter.However,the EC values of precipitation exhibited strong seasonal patterns practically identical to that for ion concentrations,consistently with minimal values in summer months,intermediate in spring and fall,and maximal in winter,which appeared highly dependent on rainfall amount.Close correlation exited between acidity and sulfate in stemflow,but hydrogen concentrations in rainfall and throughfall were strongly related to acid-base ratios R,which equals to (SO₄^2-+NO₃-)/(Ca²⁺+Mg²⁺).Lastly the distances from pollution sources produced significant effects on precipitation chemistry.

The growth and development of different generation plantations of Chinese fir were studied through the investigation of different generation,age and site plantations.The results are as follows:successive planting results in significant growth degradation of Chinese fir plantations.Compared to the first generation plantations,D.B.H of the second generation and the third generation plantations decrease by 7.29～11.76 percent and 15.63～21.47 percent respectively.Heights of the second generation and the third generation plantations decrease by 7.89～11.76 percent and 17.76～22.35 percent respectively.Volumes of the second generation and the third generation plantations decrease by 21.02～24.61 percent and 38.70～44.18 percent respectively.Moreover,as planting generation increases,fast-growing periods of DBH and height become short,stand disintegration become intensive,proportions of middle diameter group decline,proportions of small diameter group and large diameter group increase.

This paper studied the effect of agro-forestry system with on water use efficiency(WUE) of wheat planted within the shelter belt network. The results showed that within the system,the daily average WUE of wheat was increased 6.33%than CK.The daily course of WUE of wheat showed that,there was a phenomenon of “siesta,”and it can be reduced effectively in the agroforestry system.Proved by the method of PCA,the main causes of WUE increasing in the agroforestry system were air temperature,saturation deficit, leave temperature and photosynthesis rate.

The community characteristics of Quercus serrata distributed in Baotianman area,Henan Province were analyzed based on the data from 15 plots at different elevations in the area.The results showed that there was a Striking dorminance of Q.serrata in the Q.sierrata community,which was in monodominant community.The soil in the community was flrtile,flora components were plentiful,and the vertical structure of the community was complicated,which was divided into three layers:arbor layer,shrub layer,and herb layer.There were a lot of interstratum plants in the community.The index of plant diversity of the community was higher.

Leaf yield, flavonoid content, terpene lactone content, composition of flavonoid, composition of terpene lactone, seasonal variation of flavonoid, terpene lactone and distribution of flavonoid in 13 3-year-old Ginkgo biloba superior trees originated from Zhejiang, Henan, Shandong and Jiangsu Provinces, were studied. The results were as follows: (1)The differences of flavonoid content, terpene lactone content, leaf area and leaf yield for various superior trees were significant; (2)Seasonal variations of flavonoid content and terpene lactone content had the same trend and the order of concentration among quercetin, Kaemplerol and isorhamnetin was quercetin>kaemplerol>isorhamnetin, and the concentrations of ginkgolide A (GA), ginkgolids B (GB), ginkgolide C (GC), and bilobalide (BB). followed the order: GA>BB>GB or GC. The flavonoid content in Ginkgo leaves was highest in September and October, and lowest in June. However, the terpene lactone content was lowest in May, and the highest in September; (3)According to leaf yield, flavonoid yield, terpene lactone yield, 13 superior trees were divided into three types by means of cluster analysis: excellent yield-E₄, good yield-E₁, E₂, E₅, E₆, poor yield-E₃, E₇, E₈, E₁₀, W₂, W₃, E₄, E₅; (4)Among stem, root and leaf, the highest flavonoids content was in leaf, and the lowest in stem.

Genomic DNA from 55 isolates of Sphaeropsis sapinea collected on 16 pines and other 2 conifers from 13 provinces in China was studied using random amplified polymorphic DNA markers(RAPDs). The seventeen random primers produced 200 scorable DNA fragments. One hundred ninety seven fragments were polymorphic. The dendrogram generated by UPGMA divided all isolates into three groups. Cluster analysis showed that differences between isolates were not closely related to the host species and that there were complex relations between the isolate differences and geographic sources.

The paper reports two new species of genus Psyllaephagus, Encyrtidae, collected from Shaanxi and Zhejiang, China respectively. i.e. Psyllaephagus longifuniculus Xu, sp. n. ex Thysanogyna limbata and Psyllaephagus latiscapus Xu, sp. n. ex Pachypsylla celtidisgemma, which are described in detail. The genus Psyllaephagus Ashmead is a first record from China. 1 Psyllaephagus longifuniculus Xu, sp. nov. (figs. 1～3) Host: Thysanogyna limbata. Distribution: Shaanxi(Wugong). Specimens examined: holotype ♀, Wugong(34°12′N,108°0′E),Shaanxi,1954 8 21, Dept. Plant Protection, Northwest Agric. Univ., ex. Thysanogyna limbata, 5526 1a; paratypes 4♀♀2♂♂, same data as holotype. Diagnosis: this new species is similar to Psyllaephagus femoralis Borelli 1920, but can be distinguished by the following combined characters: (1)pedicel 1.8 times as long as wide, the latter 2.0 times as long as wide; (2)all funicular segments clearly longer than wide, the latter with second fifth funicular segments slightly longer than wide, sixth funicular segment quadrate; (3)clava not clearly segmented, the latter with clava clearly segmented; (4)hind femora basal 0.6 black brown, the latter with hind femora basal 0.75 black brown; (5)gaster black and with weakly metallic green reflections, the latter with gaster metallic purple and brass reflections. 2 Psyllaephagus latiscapus Xu, sp. n. (figs. 4～7) Host:Pachypsylla celtidisgemma. Distribution: Zhejiang(Hangzhou). Specimens examined: holotype ♀, Hangzhou(30°12′N, 120°48′E), Zhenjiang, 1957-5-26, CHEN Qihu, ex. Pachypsylla celtidisgemma, 5720-9; paratypes 6♀♀2♂♂, same data as holotype. Diagnosis: this new species is similar to Psyllaephagus caillardiae Sugonjaev, 1968, but can be distinguished by the following combined characters: (1)antennal scape 2.4 times as long as wide, the latter with scape 3.8 times as long as wide; (2)clava as long as fifth sixth funicular segments combined, the latter with clava as long as fourth sixth funicular segments combined; (3)fore wing with marginal vein slightly longer than wide, the latter with marginal vein quadrate.

The patterns of heavy metals in deciduous forest floor along an urban suburban rural gradient(transect 140km×20km)in New York were analyzed. 25 sampling quadrats(20m×20m)of Quercus forests in 9 study areas along the gradient were located and 4 samples of 15cm×15cm of litter patches in each quadrat were collected and analyzed for concentrations of Cu, Pb, Ni, Cr, Mn, Co, Zn and Cd in laboratory. The result reveals the relationships between urbanization and economic activities and the heavy metal pollution of forest floor. DCA analysis show that urban is greater than suburban, suburban greater than rural in total heavy metals. The concentration of heavy metals especially for Pb, Cu, Ni and Cr are decreased significantly along the gradient from city core to rural area. This is closely related to human activities. The concentrations of heavy metals are significantly negative correlated with the distance from the city core, urban land use, population in density, traffic density and road density. Heavy metals in forest floor are mainly from air pollution due to tail gases of automobiles because this area is not industrial area, no other important pollutant resources. Althouth unleaded gasoline has been used for decades in United States, Pb pollution is severe in this area. Ecological gradient of forest along urban-suburban-rural is an effective way to study the relationships between environmental pollution and urbanization.

The induced variation of some chemical substances in the body of the larch,Larix princippis-rupprechtii Mayr. injured by the larch case-bearer, Coleophora sinensis Yang, was studied. The tests were conducted in 1996～1998 in the forest areas of Wutai and Guandi Mountains located in Shanxi, China.The results showed that the North China larch could produce some secondary substances and change the compositions of some compounds in its body when it was injured by the larch case bearer. The first group of the secondary substances was tannin and free phenol. Tannin was raised so quickly with the case bearer feeding leaves in the moderate damaged forest that its content in leaves could exceed that in the other two areas. The second change was the variation of peroxidase activity in the leaves. The more damages the forest suffered, the more activities of the peroxidase the trees had. Another pest resistant factor of the forest was the dropping of its reducing sugar and Vc when the damage happened, so that the pest did not prefer to the nutrition of the leaves. These factors together took part in the chemical defense of the larch against the case-bearer attack.

Polycarboxylic acids acted as esterification agents and inorganic salts acted as catalyst in the research of wood crosslinking reaction. This new and soluble crosslinking system is poison free and pollution free system. In this work crosslinking reaction intermediate was proofed by FTIR spectra, therefor we can infer crosslinking reactions between polycarboxylic acid and wood want through cyclic anhydride intermediates.

The relationships between the values of humidity conditioning property parameters x ,y of four kind of interior decorative materials (wall paper, linden plywood, oak floor lumps and smooth MDF on both sides) and the ratio of area to volume A/V, initial moisture content of the specimens, ambient temperature were determined respectively during the period of water vapor flowing in or out. On the basis of these curves, a humidity designing graph under this condition can be obtained to provide theoretical support for designing the humidity of living environment more scientifically and completely.

The heat-conducting property of OSB wallboard was evaluated with finite difference method and intergal transformation method and compared with the traditional construction brick wall. It was indicated that the indoor temperature was determined by the materials and structure of the wall. The wall composed by OSB and glass wool had steady heat\|conducting property. It had better property of withstanding the difference of the outdoor environment than the brick wall even it's thickness was half of the brick wall. In addition, light wood composites like OSB was benefit to control the indoor temperature of the large place with air conditioner inside.

The effect of three different treatments on wood permeability and its mechanism were studied in the paper by air drying and ethanol exchange drying for green wood and by soaking in water then followed by ethanol exchange drying for air dried wood of yezo spruce (Picea jezoensis Var.komarovii) and fir (Abies nephrolep). The results showed that the specimen of green yezo spruce sapwood, heartwood and fir heartwood after air drying had a low permeability of 0.114, 0.045 and 0.111 darcy, respectively. The permeability of green yezo spruce sapwood, heartwood and fir heartwood after ethanol exchange drying was approximately 11.713, 0.074 and 0.144 darcy, respectively. Compared with the permeability of air dried specimen group, the average permeability was increased about 101.5 times, 62% and 30%, respectively. The t test showed that the difference for yezo spruce green sapwood was very significant while for yezo spruce and fir green heartwood it was not significant. The average permeability of yezo spruce sapwood and heartwood and fir heartwood samples which have been air dried for 18 months after the treatment of soaking in water for 2 weeks followed by ethanol exchange drying was increased approximately by 85%, 49%, 65.5% over their controls before the treatment, respectively. The permeability difference of soaking treatment samples versus their controls was significant at the 5% level by t test of paired comparative test. For yezo spruce green sapwood the significant increase of permeability after ethanol exchange drying compared with air drying was mainly due to the lower fraction of pit aspiration, and then the extraction of a small part of extractives from specimens were also probably responsible. For yezo spruce and fir green heartwood the increase of permeability after ethanol exchange drying compared with air drying was not significant because the ethanol exchange drying failed to prevent or decrease pits aspiration in yezo spruce and fir heartwood. For yezo spruce and fir air dried wood the increase of permeability as a result of soaking treatment was probably due to two aspects, that is, the deaspiration of some aspirated pits and the decrease of extractives in the specimen. However, for yezo spruce sapwood the former was probably the primary factor, whereas for yezo spruce and fir heartwood the latter was probably the major reason.

Ethylene, a simple organic molecule with complex biological function, has profound and versatile effects on the growth and development of higher plants as a plant hormone. These effects include promoting fruit ripening, flowering and leaf senescence, petal and leaf abscission, inhibiting seedling elongation, stimulating root initiation, relating to the sexual differentiation of flower in cucumber, promoting initiation of the flowering of pineapples, and increasing latex flow in rubber trees and so on. It is recently reported that ethylene has outstanding effect in disease resistance of plant, however, the metabolism of ethylene in disease resistance of plant is not clear. As the antisense gene technique has been applied to higher plants, the more and more antisense transgenic plants containing antisense ethylene forming genes have been obtained. Therefore it is a successful way to control effect of ethylene on the growth and development of higher plants by controlling its biosynthesis by antisense RNA, and also a successful breeding way to obtain expected transgenic plants. This paper summarizes the effect of ethylene on the growth and development of higher plants, especially on disease resistance of plants.The antisense-gene technique and the current work on the studies of transgenic plants containing antisense ethylene forming genes are also introduced.

Forestry is a major industry in environmental reproduction. The key of sustainable forestry development lies in regulating and adjusting the management behaviors of forest manager and department. By means of managing forest ecosystem effectively, sustainable forest management emphasizes that forest ecosystem provides varied material products and environment services for social and economical development. The facts that forestry confronts in China include: enormous population pressure, transform of economical system, unsoundness of forestry policy systems in effect, as well as the relative inadequate land resources, the total quantity of water resources in China is not enough, and the critical situation of ecological environment. There is practical variance in objective orientation of forestry development the government must strike up appropriate harmonious mechanism based on ensuring legal authority of forest managers, forest department and all citizenry and to realize the coordination of society, economy and environment objectives of sustainable forestry development. Forestry department must join society and ecological environment objectives into economy objectives to avoid or decrease the appearance of external diseconomy. To the sustainable forestry development, the essential task is to set up the ecologically rational, socially and economically feasible operating system in management. It has four specific tasks. Firstly, determining what natural basis for agricultural management is needed in the process of sustainable forestry development; Secondly, combining the above social demands with natural basis, to determine the social, economic and ecological environment objective, and the forest objective in the sustainable forestry development which can guarantee the realization of the three objectives; Thirdly, to determine the means of realizing the objective of sustainable forestry development, including the strategy, the special means, the technological system of the sustainable forestry development and its operating system; Fourth, to improve the guarantee system of sustainable forestry development, including the system of macro regulation and control by the government, the system of public participation, management system, the system of rational disposition of interests based on the property right system and the system of the scientific research and education in forestry. In China, the natural resourecs structure, geographical characters and the present situation of social and economic development appear conspicuous regional division rules. So the difference of needs for forest products and forest ecosystem environment function, as well as the difference of forestry development load are existed in social and economic development process for different regional or different periods in the same regional. Therefore, regionalisation has a very important significance in practices of sustainable forestry development.

The study on the high-yield poplar cultivating pattern in mid-temperate zone in China was reported, which had been used for poplar industrial exploitation on a large scale in Liaoning Province. The results showed that the survival rate of planting amounted to more than 97%, the preservation rate of juvenile tree amounted to 95.7% in an area of 2000hm² located in the colder and arider forestland. The annual average height growth of the juvenile trees was 2.6～3.0m, and the annual average growth of DBH was 2.2～3.7cm, which set a high\|yield record of cultivating poplar in a big area in China. Meanwhile, the better economic benefits have been achieved from intercropping in such cultivation pattern of the high-yield poplar.

Based on density theory of plant growth and related biological hypothesis, a theoretical model describing the whole change process of plant population density was derived, i.e. N=exp(aln²v+blnv+c), where N and v represent population density and mean volume of a plant, and a,b,c are parameters. Thereby, the authors proposed a self-thinning mechanism model which can be used in different sites and different growth stages of Chinese fir plantation, the model was described as N=exp(5.895932H^0.01351034 - 0.9225263H^-0.002829299lnv -0.1148481H^-0.01018257ln²v).The simulating result showed that the mechanism model fitted the data observed from Chinese fir plantation very well. Therefore it is very useful in practice, which will provide a scientific basis for sustainable management of Chinese fir plantation.

In this paper, the variation in fruit shape, size and its seed number were studied, and the correlativity of length and diameter of fruit to seed number for 12 species of Rhododendron from Zhejiang Province were analyzed. Based on the fruit shape and the ratio of length to diameter, 12 species of Rhododendron L. Were divided into three types. The seed number varied in different species. Rhododendron ovatum had the highest seed setting efficiency, followed by the species of Subgen Tsutsusi. The variation of seed number among the individuals of the same species was more obvious than that of the fruit. There was a significant positive correlation between the seed number in fruits and the length, diameter of fruit in most species. The results showed that fruit morphology might be an important character in systematic studies of Rhododendron L.

The study on half-sib family's experimental forest of slash pine shows that there are obvious difference among height, diameter, volume, bole form, branch size, timber density, tracheid length and so on with changed families. At family level, the timber density was negatively ralated to volume growth while there was no obvious relation between tracheid length and volume growth. Based on constrained and unconstrained selection indexes, different demands for pulpwood and construction timber, the following integrated selection results were got:families No.0.508^#, 0.1027^#, and 2.46^# are most suitable for planting pulpwood forest; families No.0.464\^#, II-101\^# and 0.508\^# are the best selection for establishing construction timber forest.

Acantholyda erythrocephala, a kind of destructire insect, is found recently in Shenyang, China. Its host tree is Pinus spp. especially Pinus tabulaeformis and P.densiflora. The injured branch, tip will be withered or even died. The harmful period of the larvae is about one month. There is one generation during a year in Shenyang area. Winter is passed as prepupae by making earth cells in the soil at the depth of 0～10cm. It can be controlled by many ways:set up closed forest; making conopy density be more than 0.7; digging out the forest soil in autumm, winter or early spring; cutting the larval nests and burning up; spraying 10% pyrethrum at 8000x ditution to the early instar larvae.

nests, in which 100 nests filled with eggs, of common tern(Sterna hirund), little tern (S.albifrons), kentish plover(Charadrius alexamdrinus) and redshank (Tringa totanus) were found in the breeding colony of saunder's gull(Larus Saundersi) when the special survey of saunder's gull was proceeding in June of 1998 around the coast of Yancheng, Jiangsu Province. It was estimated that there were about 1,633 pairs of common tern, 414 of little tern, 146 of kentish plover and 139 of redshank in the breeding colony of saunder's gull based on the egg-filled nest density of them and the colonial area of saunder's gull.

The average wood utilization percent from log to solid Products in Jilin Province was 10.5%～23.4%. In the view of internal connection and influence among log making, lumber manufacturing, drying and further processing, the causes of the wood waste were analysed; the accomplishment of the research concered wood waste and the succeeded experience of some plants were introduced; the measures for reducting the wood waste was advanced.

In order to raise the utilization ratio of forage shrub forest, the characteristics of the shrub species(Caragana intermidia, C.korshinkii,Hedysarum scroparium, H.fruticosum, H.fruticosum Pau. var. Laeve, Atraphaxisbracterate, Tamarix chinensis, Artemisia ordosica) were studied. the results showed that 8 shrubs can resist the cold or extremely hot weather. Their lateral roots were abundant. Their branches and leaves contained many coarse fat, coarse protein, all kinds of nutrient elements and 19 amino acids. The change law of their yield and the relation between yield and site, density, age, size, cutting were also studied.

In the areas of seasonal and perennial frozen soil, soil layers always contain different exent free stagnant water and frozen stagnant water, which may save the pressing need of water for spring plants. The paper, according to the laboratory stimulation of water movement in soils during freezing, analyzed formation and affecting factors for frozen stagnant water. In light of the fact that water content obviously increased after freeze. The authors advanced technical measures for afforestation in arid regions, aiming to using this part of water to assure plant's survival and growth.

In order to provide theoretical basis and technological guide for cultivating wild Pteridium aquilinum, study on the influence of planting density and fertilizers on growth and yield of Pteridium aquilinum was conducted. The results showed that the low planting density(25cm×11cm) favoured the development of root stem under earth and increase in plant height and petiole length, but resulted in decrease of yield of the fresh Pteridium aquilinum. Under the conditions of chicken dung applying, the root stems under earth developed well, plant height and petiole length increased and the third year yield of the fresh Pteridium aquilinum was significantly higher than that of the fresh Pteridium aquilinum with the treatments of compound fertilizer applying, ash fertilizer applying and no fertilizer applying. Therefore, the high planting density(25cm×5cm) with chicken dung applying is the suitable combination measures for obtaining the highest yield of fresh Pteridium aquilinum.