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The natural abundance of stable carbon and nitrogen isotopes (δ 13 C and δ 15 N) in leaves can provide comprehensive information on the physiological and ecological processes of plants and has been widely used in ecological research. However, recent studies on leaf δ 13 C and δ 15 N have focused mainly on woody species, few studies have been conducted on herbs in different vegetation types, and their differences and driving factors are still unclear. In this study, we focused on the herbs in subalpine coniferous forests, alpine shrublands, and alpine mea-dows on the eastern Qinghai-Tibet Plateau, and investigated the differences in leaf δ 13 C and δ 15 N of herbs and the driving factors. The results showed that there were significant differences in leaf δ 13 C and δ 15 N values of herbs among different vegetation types, with the highest δ 13 C and δ 15 N values in alpine meadows, followed by alpine shrublands, and the lowest in subalpine coniferous forests. Using variation partitioning analysis, we revealed that differences in leaf δ 13 C and δ 15 N of herbs among various vegetation types were driven by both leaf functional traits and climate factors, with the contribution of leaf functional traits being relatively higher than that of climate factors. Hierarchical partitioning results indicated that mean annual temperature (MAT), chlorophyll content index, leaf nitrogen content per unit area (N area ), and leaf mass per area were the main drivers of leaf δ 13 C variations of herbs across different vegetation types, while the relative importance of N area and MAT for variation in leaf δ 15 N of herbs was much higher than those other variables. There was a strong coupling relationship between leaf δ 13 C and δ 15 N as indicated by the result of the ordinary least squares regression. Our findings could provide new insights into understanding the key drivers of leaf δ 13 C and δ 15 N variations in herbs across different vegetation types.

To study sesquiterpenes with anti-metastasis breast cancer activity from Chloranthus henryi, ten sesquiterpenes ,zedoarofuran (1), chlorajapolide D (2), 4β, 8β-dihydroxy-5α(H)-eudesm-7(11)-en-8, 12-olide (3), curcolonol (4), lasianthuslactone A (5), chlomultin C (6), (1E,4Z)-8-hydroxy-6-oxogermacra-1(10), 4, 7(11) -trieno-12, 8-lactone (7), shizukanolide E (8) , shizukanolide F (9) , 9α-hydroxycurcolonol (10), and five bis-sesquiterpenes, shizukaol B (11), shizukaol C (12) , cycloshizukaol A (13) , sarcandrolide B (14) , henriol A(15), were isolated by using different kinds of column chromatography methods from the ethyl acetate part of Ch.henryi and their structures were identified based on spectroscopic methods. Compounds 2, 8, 9, and 10 were obtained from the genus Chloranthus for the first time. Compounds 2, 5, 8-10, 12,and 14 were obtained from this plant for the first time. Some isolated compounds were subjected to evaluate the anti-metastasis breast cancer activity by using pharmacological methods, and only compounds 4, 11, and 12 were potent active., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

A preparative two dimensional hydrophilic interaction liquid chromatography/reversed-phase liquid chromatography (Pre-2D-HILIC/RPLC) method was established to separate and purify the components in Trachelospermum jasminoides . The pigments and strongly polar components were removed from the crude extract after the active carbon decolorization and solid phase extraction processes. A Click XIon column (250 mm×20 mm, 10 μm) was selected as stationary phase and water-acetonitrile as mobile phases in the first dimensional HILIC. Finally, 15 fractions were collected under UV-triggered mode. In the second dimensional RPLC, a C18 column (250 mm×20 mm, 5 μm) was selected and water-acetonitrile was used as mobile phases. As a result, 14 compounds with high purity were obtained, which were further identified by mass spectrometry (MS) and nuclear magnetic resonance (NMR). Finally, 11 lignan compounds and three flavonoid compounds were obtained. The method has a good orthogonality, and can improve the resolution and the peak capacity. It is significant for the separation of complex components from Trachelospermum jasminoides .

Ionic liquids (ILs) based ultrasonic-assisted extract has been applied for the extraction of essential oil from Persicaria minor leaves. The effects of temperature, sonication time, and particle size of the plant material on the yield of essential oil were investigated. Among the different ILs employed, 1-ethyl-3-methylimidazolium acetate was the most effective, providing a 9.55% yield of the essential oil under optimum conditions (70 ℃, 25 min, IL:hexane ratio of 7:10 (v/v), particle size 60-80 mesh). The performance of 1-ethyl-3-methylimidazolium acetate in the extraction was attributed to its low viscosity and ability to disintegrate the structural matrix of the plant material. The ability of 1-ethyl-3-methylimidazolium acetate was also confirmed using the conductor like-screening model for realistic solvents. This research proves that ILs can be used to extract essential oils from lignocellulosic biomass.

To study the chemical constituents from the roots of Chirita longgangensis var. hongyao. The methanol extract was isolated and purified by silica gel, Sephadex LH-20 and preparative HPLC. Their structures were elucidated by MS and spectral data (1H, 13C-NMR). Seven compounds were isolated and identified as plantainoside A (1), plantainoside B (2), calcedarioside C (3), calcedarioside D (4), platyphylloside (5), hirsutanonol (6), and hirsutanonol-5-O-beta-D-glucopyranoside (7). Compounds 5-7 were isolated for the first time from the family Gesneriaceae.

This study compared the decoction's HPLC figures of the different processed rhizomes of Cibotium barometz including the raw, the sand-baked, the wined, the steamed and the salted, on the basis of which, with the sand-baked Drynaria fortunei decoction as the positive control group, comparingall groups' decoction, concentration of which was 104.2 g x L(-1), for 4 weeks, by their effects (s-TRAP and total scores of OPG, Ca, P, IL-6, TNF-alpha and IL-1) on retinoic acid induced male rats osteoporosis. The experiment results showed the sand-baked and the wined were better than the steamed, the salted and the raw;in the processing methods' selection, the sand-baked was a better heating method than the steamed and the rice wine was the better excipient than the salt. It provided a reference to explain the processing principle of rhizomes of C. barometz and work mechanism of anti-osteoporosis.

The pancreatic enzyme-II type collagenase digestion method was adopted for primary culture of osteoblasts, inoculation and passage. They were identified by alkaline phosphatase dye-liquor. N-butanol extract fractions from different processed products of Cibotium barometz were prepared. The above osteoblasts were jointly cultured with protocatechuic acid, protocatechuic aldehyde, kojic acid and the mixed control liquid of the above three substances, and their proliferation was detected by CCK-8. Various n-butanol extract fractions from different processed products of C. barometz showed a significant proliferative effect on osteoblasts in the order of the wined > the heated > the salted > the sand-heated and wined system > the alcohol-processed > the steamed > the crude. The q test showed no significant difference among sand-heated, alcohol-processed and steamed C. barometz, no significant difference between heated and salted C. barometz. Various control substances also showed a certain proliferative effect on osteoblasts in the order of the mixed control > protocatechuic aldehyde > protocatechuic acid > kojic acid. The q test showed no significant difference between protocatechuic aldehyde and protocatechuic acid. All of n-butanol extract fractions from different processed products of C. barometz showed a significant effect on osteoblast proliferation, of which wined C. barometz showed the best effect. All of phenolic compounds such as protocatechuic aldehyde, protocatechuic acid and kojic acid showed a significant proliferative effect on osteoblasts.

To accurately estimate forest carbon storage is of significance in researching terrestrial ecosystem carbon cycle and global change. Based on the survey data from the representative plots in Northeast China forest area (Da Xing' an Mountains, Xiao Xing' an Mountains, Zhangguangcai Mountains and Changbai Mountains) in 2007 and 2008 and the inventory data in the same period, and by using the models for estimating ground tree biomass, shrub biomass, and grass biomass and the Multi N/C 3000 for measuring forest carbon rate in laboratory, this paper calculated the forest biomass and carbon storage in the forest area, and analyzed the variation and stability of the forest carbon rates at different scales. There was an obvious difference in the carbon rates among tree organs, being the highest in leaf (0.4448), followed by in branch (0.4422), bark (0.4398), and trunk (0.4351). In Changbai and Zhangguangcai Mountains, coniferous forest had a higher carbon rate than broad-leaved forest; whereas in Daxing' an and Xiaoxing' an mountains, it was in adverse. In Northeast China forest area, the forest carbon rates were relatively stable, with a total value of 0.44.

In July-December 2010, a complete factor-controlled experiment was conducted to study the effects of litter and mineral nitrogen addition on soil organic matter decomposition (soil respiration) at the depths of 0-10 cm and 20-30 cm in Dinghu Mountain National Reserve. Coniferous needle litter and broadleaved litter were added, respectively, and 70 g N x m(-2) x yr(-1) of NH4 NO3 was applied to simulate soil nitrogen saturation whereas soil mineral nitrogen was removed by ion-exchange membrane to simulate the decreased nitrogen absorption by root. The addition of both needle litter and broadleaved litter increased the respiration rate of soil-litter system significantly from July to November, but this effect disappeared in December. Both mineral nitrogen application and soil mineral nitrogen removal increased the soil-litter respiration significantly. These results suggest that litter decomposed completely in a short period therefor had limited effects on soil organic matter decomposition and accumulation, and thus, foliar litters could be not the major source of soil organic matter, whereas soil mineral nitrogen removal could obviously promote the soil organic matter decomposition in the system.

By using litterbag method, the decomposition processes of 9 types of foliar litter in secondary conifer and broadleaf mixed forest in Changbai Mountains were assessed during a period of 34 months. The initial N and P concentrations varied greatly among the litters, and there were significant relationships between litter decomposition constant (k) and initial N concentration and C/N. The percent organic matter remaining had a significant linear correlation with percent C remaining, and a significant polynomial correlation with percent N and P remaining. The percent N and P remaining increased with the decomposition of organic matter in its initial decomposition phase, but decreased gradually in the latter decomposition phase. C/N and C/P declined with the decrease of percent organic matter remaining, and the differences in C/N or C/P among litter types decreased, being approached to 23 and 350, respectively by the end of the study. During organic matter decomposition, N/P did not change greatly, and the differences in N/P between litter types declined when the percent organic matter remaining was below 25%. Our study showed that percent of C, N and P mass remaining can be predicted by percent of organic matter mass remaining.

By adopting the concept of space as a substitute for time and taking the primitive subalpine coniferous forests as a reference, this paper investigated the forest litters in 10, 30, 40, 50 and 60-years subalpine Picea asperata stands to study the development process of litters in subalpine coniferous plantations with different restoration stages. The difference in litter development in artificial and natural stands was also discussed. The results indicated that in Picea asperata plantations with different ages, the litter pool on forest floor and the nutrient storage and maximum moisture holding capacity of litters showed a general trend of decrease at their earlier restoration stages, and of increase at the later stages. The trend of increase reached the maximum around 50 years of restoration, and then gradually leveled off or even slightly decreased. The observed litter pool (70.21 x 10(3) kg x hm(-2)), nutrient storage (4.73 x 10(3) kg x hm(-2)) and maximum moisture holding capacity (89.98 x 10(3) kg x hm(-2)) of 60-years plantations were considerably small, only accounted for 48.40%, 46.79% and 46.99% of the primitive forests, respectively. After 40 years of restoration, both artificial stands and naturally regenerated secondary forests showed similarity in litter dynamics, annual litterfall, and amount of annual nutrient returning to the soils, while a big difference in litter components, litter pool and structure on the forest floor, nutrient storage, and maximum moisture holding capacity. The difference which accounts for the difference in ecological functioning of the subalpine coniferous plantations lagging behind that of the secondary forests might be mainly caused by the less species diversity of the former.