In this study, seasonal variations in soil respiration rate (R_s) in 43-year-old and 10-year-old Robinia pseudoacacia plantations, abandoned land and cropland, and the influence mechanisms were investigated in hilly area of northern China. In 0-5 cm layers, soil organic matter content of 43-year-old and 10-year-old R. pseudoacacia plantations was 3.9 and 1.6 times of cropland, respectively. Annual soil respiration rates of 43-year-old and 10-year-old R. pseudoacacia plantations, abandoned land and cropland were 2.33, 1.21, 2.40, and 2.04 μmol·m^-2 s^-1, respectively. The cropland had the highest annual R_s, and the annual R_s of 43-year-old R. pseudoacacia plantation was significantly higher than that of 10-year-old R. pseudoacacia plantation. Regression analysis showed that soil temperature was the main environmental factor affecting the seasonal variation of R_s. The temperature sensitivity (Q₁₀) of soil respiration was 2.47, 2.53, 2.06, and 1.56 for 43-year-old and 10-year-old R. pseudoacacia plantations, abandoned land, and cropland, respectively. Compared to the cropland, two plantations presented a more temperature sensitivity of soil respiration. Moreover, there was a significant seasonal variation in Q₁₀ in the four land uses, and soil temperature was the key factor that affected the temperature sensitivity of soil respiration. The results indicated that sequestration capacity of soil organic carbon was improved in the two plantations.

Based on data of Forest Resources Monitoring Center and Continuous Forest Inventory (CFI) System in Zhejiang Province from June to September 2010, spatial variability of carbon densities in forest litter in Zhejiang Province was studied by using the Kriging interpolation method. The results showed that carbon densities in the forest litter ranged from 10.2 to 4 589.8 kg ·hm^-2 with the mean value of 1 627.2 kg ·hm^-2, which was at relatively low-level in China. Variation coefficient of carbon densities in the forest litter in Zhejiang was 0.54, Nugget/Sill ratio value was 62.75%, and the variation range was 42.69 km, suggesting that there was spatial variation in carbon densities in the forest litter in Zhejiang. The Kriging interpolation method showed that carbon densities in the forest litter in Zhejiang exhibited a decreased tendency from inland to the southeastern coast and its spatial distribution was basically consistent to the alignment of mountain ridge.

In this paper, we investigated the succession tendency of 18-48-year-old Larix principis-rupprechtii plantations in mid-low altitude and mid-high altitude districts, and proposed the corresponding management strategies. The results showed that:the succession tendency of L.principis-rupprechtii plantations in mid-low altitude district would be the pure L.principis-rupprechtii forests→mixed broadleaf-conifer forests of L.principis-rupprechtii + Quercus aliena var. acuteserrata + Acer davidii + Juglans cathayensis + Toxicodendron vernicifluum→mixed broadleaf-conifer climax communities of Quercus aliena var. acuteserrata + Juglans cathayensis + Toxicodendron verniciflum. The management strategy paid equal attention to economic benefit and ecological benefit, The close-to-nature forest management technology was used to build the different age, stratified mixed forests in which L.principis-rupprechtii was dominant species and Quercus aliena var. acuteserrata+Juglans cathayensis+ Toxicodendron vernicifluum were associated species. The succession tendency of L.principis-rupprechtii plantations in mid-high altitude district would be the pure L.principis-rupprechtii forests→mixed broadleaf-conifer forests of L.principis-rupprechtii + Pinus armandi+ Betula albo-sinensis→mixed broadleaf-conifer forests of Pinus armandi + Betula albo-sinensis + Pinus asperata (Picea wilsonii) or Abies fargesii→climax communities of Pinus asperata (Picea wilsonii) or Abies fargesii. In this district, the management strategy should consider tree species conversion, follow natural succession trend, and speed up its succession process to climax through human intervention communities of Pinus asperata(Picea wilsonii) or Abies fargesii.

In this paper, the diameter and height increment, species composition and species diversity of the upper-layer broad-leaved trees were measured during 6 years period after stand structure quantitative regulation with opening degree of the under-canopy planted P. koraiensis is trees in a mixed forest of planted Pinus koraiens with natural broad-leaved trees. The results showed that the quantitative regulation of stand structure (QR) evidently promoted the diameter and height increment of upper-layer broadleaved trees (UBT). Periodic increment of UBT in various QR treatments was all higher than that in control and the increment was increased along with the elongation of QR period. The annual increment of UBT in K=1.5 and K=2.0 treatments was significantly higher than that in control. QR improved the species composition of UBT in the treated plots, the proportion of valuable hardwood species like Fraxinus mandshurica, Phellodendron amurense and Juglans mandshurica was increased, and the proportion of pioneer species like Betula platyphylla and Populus davidiana was decreased. QR increased the species richness of UBT, increased species diversity and uniform degree of UBT or no changes, decreased ecological dominance or no changes.

In order to determine the optimal nitrogen amount for Araucaria cunninghamii,an exponential fertilization trial was conducted with 8 nitrogen levels (0,50,100,150,250,350,550,750,and 950 mg ·seedling^-1) to research the effects of different nitrogen levels on height,root-collar diameter (RCD),biomass,root activity and N content in leaves of A. cunninghamii. The result showed that: 1) Height,RCD,biomass of A. cunninghamii seedlings increased with the increase of nitrogen supply,up to 550 mg·seedling^-1,over which growth performance and biomass were stable. The root shoot ratio slightly decreased with increasing nitrogen fertilization,but the differences were not significant. 2) Root activity increased as the nitrogen fertilization increased from 0 to 550 mg·seedling^-1 and then decreased from 550 to 950 mg·seedling^-1. 3) From the response curves of seedling dry mass and N content to the increasing N supply, the sufficient and optimum nitrogen loading rates for A. cunninghamii seedlings were found to be 558.82 and 573.55 mg·seedling^-1,respectively. Based on these results,it could be concluded that 550~575 mg ·seedling^-1 would be the optimal nitrogen amount for A. cunninghamii seedlings.

To reveal the relationship between the structure and function of vegetative storage proteins in Ginkgo biloba, the vegetative storage proteins were separated and purified by DEAE-Sepharose FF ion-exchange chromatography and Sephadex G-75 gel chromatography. A target protein was obtained and its molecule weight was 36 kDa. The mass-spectrometry showed that there were two peptide sequences which were consistent to some sequences of the Soybean storage protein (29 kDa) and the Dioscorea storage protein (30 kDa). The infrared spectrometry indicated that the secondary structure of the protein was mainly in β-sheet conformations.

The rooting ability of Picea abies cuttings, exposed to full-light and auto-interval misting, and the affecting factors were studied with the orthogonal experimental design (L₈ (1⁴×2²)) in Xiaolong Mountain of Gansu Province. The factors included three hormones (ABT₁, IBA and NAA) with four levels (0, 50, 100, 200 mg ·L^-1), two types of cutting wood (twig, and twig with 1.5-year-old branch), and two levels of treatment time (1 h and 2 h). The experiment arrangement was blocked with 2 replications in random. With these treatments and conditions, the rooting rate of 823 individuals was monitored. The results showed that the reasonable concentration of ABT₁ and IBA had dominant influence on rooting of P. abies shoot cutting, the types of shoot cutting and treatment time had different effects on rooting with different types of hormones. The rooting rate of shoot cutting was significantly different with different levels of ABT₁. The treatment of 50 mg ·L^-1 ABT₁ + twig with branch + 2 h dipping had the maximal rooting rate with 89.0%, and the treatment of 200 mg ·L^-1 ABT₁ + twig with branch + 2 h dipping had maximal rooting number. IBA concentration itself had no significant influence on rooting ability of the shoot cutting, but the treatment of 50 mg ·L^-1 IBA + twig with branch + 2 h dipping, and 100 mg ·L^-1 IBA + twig with branch + 1 h dipping had the maximal rooting rate and maximal rooting number, respectively. The high concentration NAA had a negative effect on rooting of the calli, therefore, it is not recommended for application in practice, but low concentration NAA with short time soaking could improve rooting from the bark. The variation range of P. abies rooting ability was 0–100.00%, and the potential of individual selection was great. The rooting properties of P. abies was not correlated to growth properties, thus attention must also be paid to the choice of rooting properties when growth properties of P. abies was selected for clonal selection and cutting orchard construction. There were significantly positive correlations among rooting rate, rooting number and average length of roots. Thus, once rooting rate, an easy measured property, was selected, other properties of rooting would be improved genetically.

The processes of pollination, fertilization and embryo development in Camellia oleifera‘Xianglin XLC15’were examined under a microscope. The results showed that the pollen germination occurred in 2 h after pollination, the pollen tubes grew up to the base of the style in 48 h after pollination. The pollen tubes entered into the embryo sac through a degenerated synergid, which belonged to the porogamy type. Approximate 23% of the pollen tubes were observed to penetrate into the embryo sac. The fusion of sperm cells and polar nucleus mainly occurred in 3-10 days after pollination, while fusion of sperm cell and egg cell occurred in 5-16 days after pollination. The double fertilization was of the premitotic syngamy type. The primary endosperm nucleus did not begin to mitosis until they were formed, and the development of endosperm belonged to the nuclear type. Endosperm nucleuses were extremely underdeveloped, the endosperm was composed with large but few cells. The zygote resumed rapid growth after a dormant period of 4 months, and later globular embryo with obvious suspensor formation in 200 days following pollination. Thus, the development of embryo conformed to the Solanad type.

Homeobox genes play important roles in determining plant morphogenesis. A homeobox gene was isolated from Dendrocalamus latiflorus with RT-PCR and RACE methods. The full length of the cDNA was 1 452 bp which would encode a 330-aa protein containing one KNOX1 domain, one KNOX2 domain, one ELK domain and one Homeobox domain, indicating that it belongs to KNOX protein, and the gene was designed as DlKNOX1 . Tissue specific expression showed that DlKNOX1 expressed in knob with the highest level, followed by in stem and sheath, and the lowest in leaf. DlKNOX1 gene was constructed into the multiple cloning sites of pPZP vector driven by a 35S promoter, and transferred into Arabidopsis thaliana. RT-PCR analysis showed that DlKNOX1 was expressed in the transgenic plants. The phenotype of transgenics showed that flowering time was later than that of wild type, and the pods position changed obviously, which suggested that DlKNOX1 might participate in the regulation of D. latiflorus morphogenesis.

Eukaryotic translation initiation factor 5A (eIF5A) plays an important role in plant development and various stresses. In this study, the full length PtoeIF5A2 (GenBank Accession number: HQ529480) cDNA was isolated from the cDNA library prepared from 2-month-old Populus tomentosa‘BJHR01’seedlings using RT-PCR technique. The PtoeIF5A2 coding region contained 483 nucleotides, encoding 160 amino acids with the molecular weight of about 18 kDa and PI of 5.76. The real time quantitative RT-PCR displayed that the expression of PtoeIF5A2 was highest in leaves in 6-month-old seedlings, about 5 times higher than that of in root. Moreover, the expression of PtoeIF5A2 in P. tomentosa responded to the drought, ABA and low temperature, especially NaCl treatment. After 24 h under NaCl, the PtoeIF5A2 expression was 25 times higher than control, and the PtoeIF5A2 promoter contained 6 response elements to pathogen and salinity, indicating that PtoeIF5A2 would be mainly involved in response of salt stress.

A new forest method for retrieving above ground biomass (AGB) was developed based on Polarization Coherence Tomograhpy (PCT) technique using airborne single baseline polarimetric interferometric SAR (Pol-InSAR) data. First of all, forest vertical distribution of relative reflectivity (FVDRR) for each pixel was extracted using single baseline PCT technique. Then, the mean FVDRR for each forest stand was calculated from the FVDRR of all the pixels inside each corresponding forest stand. Thirdly, the mean FVDRR of each stand was fitted to Gaussion function and the forest canopy height, here defined as tomography canopy height (TomH), was extracted. Finally, regression analysis method and cross-validation approach were applied to build and assess forest AGB estimation model based on TomH using 20 in-situ forest stand AGB as reference. The result showed that the determination coefficient R² was 0.822 and RMSE was 53.14 t ·hm^-2 of the forest AGB retrieval model based on TomH. TomH had a higher correlation with in-situ forest AGB than that of three-stage inversed forest height. This approach is simple and easy to implement, and it can improve the accuracy of forest AGB estimation. Moreover, there was no signal saturation in our study area.

Though RTK is a satellite positioning technology with high precision, GPS RTK technology is seldom used in forests due to the obstruction of forest canopy to the satellite signal. GNSS RTK with two satellite systems has broad application prospects. The effects of canopy openness on positioning availability and initialization time of GNSS RTK were studied in secondary poplar-birch forests in mountain land in north Hebei, positioning with GPS+GLONASS RTK system, measuring forest canopy openness with hemispherical photograph. The results showed that canopy openness was the most fitting indicator, since hemispherical photograph could represent well forest environment and most satellite had medium elevation angle. Satellite number was enough to meet the positioning requirements. Forest canopy openness had significant positive correlation with common satellite numbers. PDOP value more than 92.4% was less than 4, and there was a good satellite geometric distribution. SNR was significantly positively correlated to canopy openness, and was affected greatly by forest environment. All indicator of positioning availability were good when canopy openness was more than 0.25. Average initialization time of RTK was becoming shorter with the increasing canopy openness. The suitable occupation time was 15 min with regard to surveying duration and surveying efficiency.

Forest biomass estimation is the basis of carbon cycle in forest ecosystems and carbon dynamic analysis. Therefore, the accurate estimate of biomass is very important. Establishing biomass models is a major means of biomass estimation on a large scale. Based on remote sensing images of Changbai Mountain region in Heilongjiang province and data from continuous forest inventory of 122 permanent sample plots, 171 independent variables was chosed including options include band grayscale value, the different band combinations between the grey value of linear and nonlinear, texture information and environmental factors. Respectively adopting conventional regression model of biomass without canopy density variable, conventional regression model of biomass with canopy density variable, consociation equations model of biomass and canopy density, forest biomass was calculated in the Changbai Mountain region in Heilongjiang province, and precision evaluation was carried out. Research results showed that: simultaneous equations model of biomass and canopy density was the optimal model, with the accuracy of the model as high as 83.1%, and the precision was increased by 6%-7% compared with the other two models. This study provides a new train of thought for the estimate of forest biomass using the remote sensing.

Sustainable forest management on regional scales attributed to accurate biomass estimates, which were influenced by multiple biotic and abiotic factors. Combining forest inventory data with yield sampling, we calculated biomass accumulation of Eucalypt plantation in Nanjing, a county in Fujian, and presented spatial distribution of biomass differences between values using local biomass model gained in this study and default biomass model in many existing references. The source of differences and their relative contribution rates were analyzed using BRT (boosted regression trees) method. The result indicated that biomass accumulation calculated using default biomass model was overestimated by 20.88%, and the largest error source ascribed to stand conditions which accounting for 70.94% of biomass differences. Among all variables, stand age was dominant due to contributing 54.92% of biomass differences which declined along with stand age growth. In addition, abiotic factors had less effect on biomass differences with 29.06%; besides, elevation and soil depth were, respectively, the key variables among topography and soil factors.

In this research,vegetation and building parameters were extracted accurately by using multi-feature fusion and object-oriented classification with LiDAR and CCD data,based on the digital elevation model calculated by the refined information extraction algorithm using LiDAR. By integrating hemispherical viewshed solar radiation model,the individual-building based rooftop-received solar radiation was mapped across four seasons,and the shading effects of rooftops by neighborhood trees were quantitatively estimated. The result demonstrated that: compared with the building structure parameters extract from sole LiDAR data,the results by the integration of LiDAR and CCD had a higher accuracy; it also reflected the seasonal dynamics of the shading effects by high-rise buildings and the shading on low-height buildings by surrounded tall trees; there existed a positive correlation between vegetation structure parameters and rooftop-received solar reduction,whereas the influence by building structure parameters was mild and the general trend was not significant.

To understand the community structure and its seasonal change of soil nematode in urban forests of Southern China, the litter invertebrates in four plantation of Schima superba, Eucalyptus urophylla, Thyrsostachys siamensis, and Vatica astrotricha in Changgangshan Natural Reserve of Guangzhou were sampled monthly from January 2008 to December 2008. A total of 31 570 nematode individuals were collected, belonging to two classes, eight orders, 39 families and 93 genera. Aphelenchoides, Aphelenchus, and Nothotylenchus were the dominant genera in the experimental region and most of them lived in fall-litter. Based on trophic groups classification, the majority of soil nematodes in the four plantations was Bacterivores (BA) and Fungivores (FF); and the second-highest was Plant-feeding nematodes (PF).The maximum population density of nematodes occurred in October. The soil nematode density was significantly correlated to soil moisture (r=0.631;P<0.01). Species richness of Fungivorous nematodes was higher than others in different vegetation communities and soil depth. The total soil nematode density and the trophic groups varied significantly (P<0.01) with different months. The number of Bacterivores and Fungivores nematodes (P<0.01) and the value of WI changed significantly (P<0.05) in different months. The number of Fungivores and the value of WI varied significantly (P<0.01) in different soil depths. The value of H' varied significantly in different vegetation communities (P<0.05).

The unique numbing components in prickly ash (Zanthoxylum) consist of 8 different types of chained unsaturated fatty acid acylamides. It is meaningful to establish a rapid determination method of the numbing components contents (total acylamides) in prickly ash in evaluating the quality of prickly ash and its products. A three-levels and four-factors orthogonal experiment was conducted. The optimum ultrasonic-assisted extraction conditions for the total acylamides extract were in a 95% ethanol solvent with a 1:10 solid-liquid ratio at 50 ℃ for 2.5 h. Through a comparison study of the rapid formaldehyde titration method with HPLC approach for detecting the total acylamides contents in prickly ash, the adjusted coefficient of determination with the quick formaldehyde titration method was 2.269 6 (R² = 0.978 1). In addition, the rapid formaldehyde titration assay was used to detect the total acylamides contents of 14 types of prickly ash from different habitats. The results indicated that the Z.bungeanum, grown in alpine regions, had the highest total acylamides contents, followed by Z.armatum and then Z.bungeanum, found in low-relief terrain.

Wood coating can undergo degradation when exposed to the UV and visible light, moisture and oxidation condition, and its decorative and protective function will be destroyed. Therefore, the issues about the failure time, form, degree and mechanism, prevention and detection of wood coating failure have become the concerns of scientists in wood and painting fields. Presently, plenty of researches on wood coating failure have been reported in abroad, but few researches for wood coating failure forms, mechanisms and prevention were investigated in China. In order to provide scientific directions for the rapid assessment and effective prevention of wood coating failure, as well as the development and evaluation of coating in wood industry, the forms, mechanisms and assessment methods of wood coating failure in recent decades were reviewed in this paper.

In this study, the effects of different concentration trace elements in NT medium on adventitious root growth, the accumulation of total alkaloid and triptolide of Tripterygium wilfordii were investigated. The results showed that the trace elements of Mn,Zn,Cu,Co,B,I and Mo influenced the adventitious root growth and the accumulation of total alkaloid and triptolide. The optimal NT medium trace elements for the growth of adventitious root were 2 times the concentration of MnSO₄,with concentrations of ZnSO₄,CuSO₄,CoCl₂,H₃BO₃ and KI maintained unchanged and 2 times concentrations of Na₂MoO₄.As for the accumulation of total alkaloids, the concentration of KI had no impact on the accumulation of total alkaloids, 2 times the concentration of CoCI₂ and CuSO₄, removal of H₃BO₃ and Na₂MoO₄, and 4 times concentrations of MnSO₄ and ZnSO₄ were suitable. In NT medium, 2 times the concentration of ZnSO₄ and CuSO₄, removal of H₃BO₃, Na₂MoO₄ and CoCl₂, and 4 times concentrations of MnSO₄ and KI were optimal for the accumulation of triptolide.

The aim of this study was to enhance manganese peroxidase (MnP) gene express by Lenzites gibbosa MnP production for using Aspergillus nidulans. In this study, an auxotrophic strain, TN02A7, of A.nidulans was used as the host of L. gibbosa.The conidiophores of TN02A7 were used to produce the protoplasts by different cell wall lyases, including lywallzyme, cellulase and snailase which were mixed together by 1:1:1 for effectively break down the wall and produce protoplasts. PEG/CaCl₂ were used to mediate transformation of L. gibbosa, containing a gene encoding for manganese peroxidase 2 (Lg-MnP2), into the TN02A7 protoplast. The newly obtained transformant strain, TN02A7-Lg-mnp2 , and TN02A7 were cultured in the same shaking medium containing lignin and the MnP activity was detected. The result showed that TN02A7-Lg-mnp2 could produce MnP activity up to 17 U ·L^-1 in 96 h, while TN02A7 did not produce MnP activity at any time, indicating that the gene Lg-mnp2 had been successfully transformed into TN02A7-Lg-mnp2 and expressed in lignin environment. This study provided a new method to produce MnP.