Abstract:Hydrological effects of coniferous and broadleaved mixed forest ecosystem in Dinghushan were studied from August 2002 to July 2003. The total precipitation during this period was 1 690 mm, of which the net precipitation under canopy was 1 212.7 mm, accounting for 72% of the total. The amounts of throughfall and stemflow were 1 125.3 mm and 87.4 mm, respectively, accounting for 66.6% and 5.2% of the total precipitation, respectively. Canopy interception was 447.3 mm, with an interception rate of 28.2%. The surface runoff was 621 mm (about 3.7％ oftotal precipitation)．It was shown that the amount of canopy interception increased with the increasing of precipitation，but having various tendency for different precipitation intensity classes． However, the critical canopy interception for precipitation event was about 25 mm． Throughfall and stemflow were linearly related to the precipitation．The surface runoff was also linearly related to precipitation when the daily precipitation was ≤ 30 mm， but nonlinearly related to precipitation at >30 mm． Compared with monsoon evergreen broadleaved forest or pure coniferOLlS forest，the coniferous an d broadleaved mixed forest had a greater hydro-ecological effect on decreasing surface runofr and water and soil conservation.

Abstract:The amount and composition of soil microbes including bacteria, fungi and actinomycetes were investigated in July 2002 in Heshan Hillyland Interdisciplinary Station where afforestation was undertaken on waste downland since 1983. Soil samples were collected at 0-15 cm depth from plots of seven sites, i.e. I, Pinus massoniana forest (planted in 1983); II, Schima wallichii forest (1987)； III, Mixed forest of legumes (planted during 1983-1987)； IV, Acacia mangium forest (1983)； V, Orchard (1985)； VI Fish pond sludge(fish pond was established in 1985)；and VII，Secondary forest near village．Microbial am ount Was highest in site VII(6.323×10⁶g^-1 dry soil)，folowed byⅣ，V，Ⅱ,III,VI,and lowest inI(1.424xl06 g dry sold．111e number ofsoil microbes was in the order：bacteria > actinomycetes > fungi，which Was similar to the results obtained in l988．However，the percentage ofbacteria Was increased rapidly in all sites(from 32.1％-79.9％in 1988 to 71.4％-87.7％now)，and the percentage of fungi and actinomycetes were decreased (from 6.8％-28.6％and 6.8％-39.3％to 1.1％-9.6％and 9.2％-22.7％，respectively)．Soil microbial biomass(mg C_mic (100g)^-1 dry soil)in sites was in the order：IV(57.11)> V(47.79)>II(42.55)>I(29.68)，which had a similar sequence for soil organic carbon in the corresponding sites．The increase of total amount of microbes，especially ofthe number and percentage of bactefia suggests that the soil properties under artificial forests were improved， and most obvious result Was foun d in soil un der aforestation by Acacia mangium．

Abstract:Net photosynthetic rate (Pn), stomatal conductance (Gs), intrinsic water use efficiency (WUE) and chlorophyll content were measured in the leaves of Kmeria septentrionalis seedlings grown in pots withvarious soil water contents during July 15-19 and October 20-25, 2001. Decrease of soil water content in summer and autumn reduced the leaf dry weight per unit area and chlorophyll content in the seedlings. In July, highest photosynthetic rate was found at 9:00 pm in sunny day. The Pn of seedlings in treatments with soil water content at high(WH)，mediam(WM) ，and low levels were 4.41±1.1O μmol m^-2s^-1 ,4.28±1.23 μmol m^-2s^-1 and 1.89±0.94 μmol m^-2s^-1，respectively．WH，WM and WL represent the soil water contents are 60％-65％, 45％-50％ and35％-40％ of the field water holding capacity， respectively． Low Pn occurred in plants grown under soil water treatments of WL． A pattern with double peaks in daily photosynthetic course was observed in leaves of the seedlings under soil with all the three treatments．Gs an d intrinsic WUE daily courses also showed similar paUem ． In October，daily high Pn appeared at 12：00 in plants in WH group and those in WM and WL groups were found at 9：00．A pattern with single peak in daily photosyn thetic course was observed in 3 groups． Average values of Pn，Gs and intrinsic WUE were higher in autumn than those in summer in all the three groups．However,the Pn，Gs and intrinsic WUE were all low in soils with low water content, whatever in summer or autumn． The results suggest that the control of soil water content may help to promote the growth of septentrionalis and increase the effectiveness of ex situ conservation.

Abstract:Wood structure of six Sonneratia species from Mangrove Nature Reserve at Dongzhai Port, Hainan Province, was observed under LM, SEM and Laser scanning confocal microscope. Ray height and ray width can be used for diagnostic or subsidiary diagnostic features to distinguish S. ovata from other Sonneratia species.Sonneratia forms a monophyletic group which has a closer affinity to Lagerstroemia (Lythraceae) instead of Duabanga (Sonneraceae). The result of clustering based on quantitative data of vessel elements (pores) suggests that the Sonneratia species evolved into two clades，one including S. aseoalris and S．paracaseolaris that has the wider vessel and lower pore density sug esting a high conducting eficiency，the other including S．alba，S. ovata，S．apetala and S．hainanensis that has the narrower vessel and higher pore density resulting in high conducting safety．

Abstract:Specimens collected from ten populations of Paeonia lactiflora Pall. or P. lactiflora Pall. var.trichocarpa (Bunge) Stern grown in six plantation sites (provinces) in China were studied for the purpose ofidentifying the traditional Chinese herbs namely Chuanbaishao, Bobaishao, Hangbaishao, Hezebaishao, Donghai- baishao, and Hanchengbaishao. Morphologically, Chuanbaishao population with pink flowers was identified as P. lactiflora, while that with white flowers was P. lactiflora var. trichocarpa. As for Hangbaishao from Zhejiang Province，all colections from populations with whether red or pink，or white flowers were recognized as var. trichocarpa．The rest were referred to P lactiflora．The diagnostic anatomical features ofthe roots are described,a key for morphological identification of the plants iS provided.

Abstract:The composition and content of fatty acids in three marine(Chaetoceros simplex,Pavlova virides,Platymonas sp.)and three freshwater microalgae(Chlorella pyrenoidosa,Scenedesmus obliquus,Spirulina maxima)were measured. Major saturated fatty acids in the marine microalgae were characterized by those with 14-20 carbons, while those in the freshwater microalgae were only C16:0 and C18:0.The monounsaturated fatty acids in both marine and freshwater microalgae were mainly C16:1ω7 and C18:1ω9. Major polyunsaturated fatty acids in the marine microalgae were Eicosapentaenoic acid an d Docosahexaenoic acid, while those in the freshwater microalgae were polyunsaturated fatty acids of 18 carbons.

Abstract:The essential oil was obtained at a yield of 0.51% by steam distillation from the leaves of Syzygium buxifolium. The main components were identified by GC-MS as caryophyllene (37.623%),α-selinene (9.627%),β-selinene (9.408%) and copaene (5.360%). Antibacterial experiments showed that the essential oil had stronginhibitory and bactericidal activities against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Proteusvulgaris and Sarcina lutea.

Abstract:Petal growth and anthocyanin content in ray florets of Gerbera hybrida (Compositae) were determined during the six phases (from P1 to P6) of head development, and the development of pollen sacs and grains in disc florets were observed as well. The results showed that the anthocyanin in P3 phase started to increaseaccompanying the maturation of pollen grains in outer whorls of disc florets. The growth phase and pigmentation of ray florets were closely related to the stamen development of disc florets in head of the plant.

Abstract:Four-leaf seedlings of tobacco were used to study the resistance to tobacco mosaic virus (TMV). After the seedlings were sprayed with 1 mg ml-1 methyl jasmonate (MJ) once a day for 3 days, then TMV was inoculated to the leaves. Among three tobacco varieties, brazil tobacco (BX) showed lower disease index than the other two (GH55 and K326). Endochitinase, β1,3-Glucanase, superoxide dismutase (SOD) and lipoxigenase activities increased in MJ-treated BX tobacco seedlings. It is suggested that MJ plays an important role in the increase of SOD and in the resistance of BX tobacoo against TMV.

Abstract:Spraying ZnSO₄·7H₂O and Na₂MoO₃·2H₂O on the leaves of balsam pear (Momordica charantia cv. Zhuzhou Changbai) grown in the field could significantly increase the yield of balsam pear and the contents of polyamines (PAs), putrescine (Put), spermidine (Spd), spermine (Spm), indole acetic acid (IAA), gibberellic acid (GA₃) and ascorbic acid (ASA) and the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in the leaves. It also reduced malondialdehyde (MDA), abscisic acid (ABA) content and autoxidation rate (AOR)in leaves，which inhibited membrane lipid peroxidation and retarded the senescence of leaves．The statistics analysis showed a significant positive correlation between yields and IAA，GA₃，PAs，SOD，POD，CAT， but a significant negative corelation between yields and MDA，AOR,ABA．Whereas in the leaves，the content of MDA was positively related to the contents of ABA and AOR，but negatively to those of PAs，IAA ，GA₃，SOD，POD and CAT．

Abstract:To evaluate the effects of blue light and sucrose on anthocyanin accumulation and chalcone synthase gene (CHS) expression, the leaves of 13-day-old seedlings of wild type Arabidopsis (WT) and hy4 mutant grown under 20μmol m-2 s-1 white light were used in the experiments. After irradiation by blue light (BL), anthocyanin content in leaves of WT increased with the increase of blue light intensity and irradiation duration. Anthocyanin content in hy4 mutant was lower than that in WT after BL treatment, which demonstratedthat cryptochrome 1(cry1)mediated the BL response in anthocyanin accumulation．CHS gene expression detected by Northern blot in the、WT leaves was induced by BL and it could be detected after 4 hours and reached a peak after 8 hours，and then the gene expression declined．BL could not induce any gene expression in hy4 mutant indicating cryl is the photoreceptor mediating the blue-light-induced CHS gene expression． It was observed that the increase ofan thocyanin an d gene expression were weakened in sucrose-free medium under blue light treatment． Sucrose may act not only as an energy source but also a component in blue-light-induced signal transduction of anthocyanin accumulation and CHS expression.

Abstract:The improved method for isolation of transgenic sugarcane genomic DNA could rapidly and simplyextract high quality DNA from a few leaves of transgenic sugarcane. The isolated DNA is essentially free of polysaccharides, polyphenols, RNA and other major contaminants. Ultraviolet absorbance spectrum analysis andgel electrophoresis results showed that DNA samples obtained by the method possessed the standard ultraviolet absorbance spectrum of pure DNA, with 1.7-1.9 A₂₆₀/A₂₈₀ and 1.8-2.0 A₂₆₀/A₂₃₀. The yield was about 45-60 μg DNA per 100 mg young leaves．The total DNA prepared by this procedure could be used for PCR, restriction enzyme digestion and southern blotting.

Abstract:The growth of mung bean radicles decreased with the increase of NaCl concentration in incubationsolution, and the detected ultraweak photon emission intensity declined markedly as well. During germination of mung bean seeds, superoxide dismutase (SOD) activity also decreased as NaCl concentration increased. SODactivity was closely related to biophoton intensity. The results show that ultraweak photon emission detection is useful for the study of the plant response to salt stress.

Abstract:Nodal regments of tropical fruit Averrhoa carambola (Oxalidaceae) were used as explants to investigate optimum conditions for rapid propagation. Among cytokinins (1.0 mg L^-1), zeatin (1.0 mg L^-1) was best for culture, and kinetin (1.0 mg L^-1) the worst. MS medium supplemented with 0.5 mg L^-1 BA, 0.2 mg L^-1 NAA and 0.2 mg L^-1 GA was optimal for the plantlet growth, the proliferation coefficient being as high as 3.7, and the rate of abnormal plantlets was only 23.3%. As for rooting, half-strengh MS medium containing 0.2 mg L^-1 IBA，0.1 mg L^-1 and 2％-3％ sucrose was the best．The rooting rate was 87.1％ ．

Abstract:After a brief introduction to the history, fundamental concept, method and steps of emergy theory and analysis method, the current situation and future trends of six frontiers of emergy study are reviewed anddiscussed. The six frontier fields in emergy study include: applied research, emergy theory and the optimization of evaluation system, the integration study of emergy in connection with landscape ecology and otherthermodynamic theory, measuring method, and unification of emergy transformity.

Abstract:Recent studies on decontamination of heavy metals by wetland plants and soils are reviewed. Wetland plays an important role in removal of heavy metal contamination, which is under intensive study. Most researches have been focused on the function and the processes of wetlands. The functional compositions of wetland include plants, microbes, water and soil, among which plants play a key role in the removal of heavy metals. Phytoremediationis contributed mainly from three parts: phytoextraction, phytovolatilization and phytostabilization．Plants have great effects in heavy metal removal via modulating pH,transporting O₂ stimulating microbes, erc．The detaining of heavy metals in soils is related to soil particle size and other traits, such as the basic elements of soil,organic material, pH, etc．It is proved that the organic material content has the effect of concentrating heavy metals via cation exchange， surface adsorption，chelation with solid organic material，etc．But it is also found that the stability of the organic complexation，chelating with acid，is highly pH dependent．Wetland，therefre，is a system in which most of the factors will work together and affect each other．The function of wetland，especially those with rich biodiversity, is extremely complex．In artificial wetland construction and research，more attention should be paid to the cooperation of various factors than the function ofindividual one．

Abstract:The development of annona fruit production is restricted due to the difficulty in fresh-keeping of the fruits during storage and transportation. This paper reviews postharvest physiology of annonas, including respiration and ethylene production, relevant enzymes, fruit softening, fruit browning, and postharvest pathology.

Abstract:This paper briefly reviews the studies of medicinal plant Jatropha curcas on the following aspects: morphology and habitat; effective components including terpens, flavons, fats, coumarins, sterols, etc.; toxicity and pharmacological activities; medicinal use; and application prospects.