Vitex Negundo Var Research Articles

Natural distribution and community ecological characteristics of Taxus chinensis var. mairei in Shanxi Province, China.

Taxus chinensis var. mairei is a national Category 1 protective species in China, with its northernmost natural distribution to the southeast of Shanxi Province, China. This study was conducted to investigate the natural distribution of T. chinensis var. mairei in Shanxi Province. The community classification, species diversity, population structure and competition intensity of T. chinensis var. mairei were studied. The results showed that T. chinensis var. mairei mainly formed four community types, including the community of T. chinensis var. mairei + Carpinus turczaninowii, the community of T. chinensis var. mairei - Vitex negundo var. heterophylla, the community T. chinensis var. mairei - Clerodendrum trichotomum and the community of T. chinensis var. mairei + Quercus variabilis. T. chinensis var. mairei was concentratedly distributed in Mohe of Linchuan County and Manghe Nature Reserve of Yangcheng County, and scattered in some other areas. The communities had an obviously vertical structure, with T. chinensis var. mairei trees growing into main canopy which were about 8-10 m high in mixed forests and 5-6 m high in pure forests. The species diversity index and evenness index had significant difference among the four community types. The average height of T. chinensis var. mairei was 5.16 m. The individuals in tree layer and succession layer were 43.4% and 56.6%, respectively, while they were scarce in the regeneration layer. 67.6% of the trees were small-diameter (DBH＜16 cm) and only 4.0% were large-diameter (32 cm≤DBH＜40 cm). T. chinensis var. mairei was considered to be lack of seedlings because only 4 seedlings were found, which might result in the declination of this species in future. T. chinensis var. mairei in Shanxi Province showed relatively concentrated distribution, with most individuals being small-diameter, resulting in tense intraspecific competition which accounted for 61.8% of the total intensity. The interspecific competition to T. chinensis var. mairei was mainly from C. turczaninowii and Q. variabilis, which were two dominant tree species with larger population in this area.

Lignans and triterpenoids from Vitex negundo var. heterophylla and their biological evaluation

Three new phenylnaphthalene-type lignans, vitexnegheteroins E-G (1–3), and a new polyoxygenated ursane-type triterpene, vitexnegheteroin H (9), were isolated from the seeds of Vitex negundo var. heterophylla, together with ten known compounds. Their structures were established on the basis of extensive 1D and 2D NMR experiments, as well as their mass spectroscopic data. The absolute configurations of compounds 1 and 2 were determined by comparing their experimental ECD spectra with that calculated by the time-dependent density functional theory (TDDFT) method. The isolates were evaluated for their cytotoxicities against three human cancer cell lines, inhibitory activities on lipopolysaccharide-induced NO production in murine microglial BV-2 cells, and antioxidant activities for ABTS radical scavenging.

Chemical constituents and their bioactivities from the fruits of Vitex negundo var. cannabifolia

Phytochemical investigation of the fruits of Vitex negundo var. cannabifolia led to the isolation of 22 compounds (1–22). Their structures were elucidated mainly by spectroscopic analysis and comparison with the literature data. Among them, compounds 1 and 2 were two new artificial lignans. Primary bioassay showed that the polymethoxyflavones 9–12 displayed moderate-to-weak cytotoxicity against human HepG2 and rat C6 cell lines, while the triterpenoids 13–17 exhibited significant brine shrimp lethality with LC50values of 7.5–29.4 μM.

Two new lignans from the aerial part of Vitex negundo

A new phenyldihydronaphthalene-type lignan, (3R,4S)-6-hydroxy-4-(4-hydroxy- 3-methoxyphenyl)-5,7-dimethoxy-3,4-dihydro-2-naphthaldehyde-3a-O-β-d-glucopyranoside (1), and a new phenylnaphthalene-type lignan, 6,7,4′-trihydroxy-3′-methoxy-2,3- cycloligna-1,4-dien-2a,3a-olide (2), along with 10-known lignan derivatives (3–12) were isolated from the aerial part of Vitex negundo var. heterophylla. Their structures were established by comprehensive 1D- and 2D-NMR spectroscopic analyses.

Diurnal variation in soil respiration under different land uses on Taihang Mountain, North China

Abstract The aim of this paper is to evaluate the diurnal variation in soil respiration under different land use types on Taihang Mountain, North China, and to understand its response to environmental factors (e.g., soil temperature and moisture) and forest management. Diurnal variations in soil respiration from plantations (Robinia pseudoacacia, Punica granatum, and Ziziphus jujuba), naturally regenerated forests (Vitex negundo var. heterophylla), grasslands (Bothriochloa ischaemum), and farmlands (winter wheat/summer maize) were measured using an LI-8100 automated soil CO2 flux system from May 2012 to April 2013. The results indicated that land use type had a significant effect on the diurnal variation of soil respiration. The diurnal soil respiration from farmlands was highest, followed by Ziziphus jujube, R. pseudoacacia, P. granatum, the lower soil CO2 efflux was found from B. ischaemum and V. negundo var. heterophylla. The diurnal soil respiration across different land use types was significantly affected by soil temperature and moisture, and their interaction. Precipitation-stimulated soil respiration increased more in soil with low water content and less in soil with high water content. The lower diurnal soil respiration from naturally regenerated forests suggests that naturally regenerated vegetation is the optimal vegetation type for reducing global warming.

New phenolic compounds from Vitex negundo var. heterophylla and their antioxidant and NO inhibitory activities

Four new phenolic compounds, vitexnegheteroins A–D (1–4), were isolated from the seeds of Vitex negundo var. heterophylla, together with eight known compounds. Their structures were established on the basis of extensive 1D and 2D NMR experiments, as well as their mass spectroscopic data. The absolute configuration of compound 4 was determined by comparing its experimental CD spectrum with that calculated by the time-dependent density functional theory (TDDFT) method. The antioxidant and anti-inflammatory activities of these phenolics were also evaluated. Most of the compounds showed strong ABTS radical scavenging activities and all the tested isolates exhibited inhibitory effects on lipopolysaccharide-induced NO production in murine microglial BV-2 cells. The bioactive studies supported the traditional use of this edible aromatic plant and disclosed the potency of it to be developed as new antioxidant and anti-inflammatory functional food.

경주국립공원 구미산 지구에 분포하는 관속식물상

The purpose of this study is to offer the flora data for conserving the biodiversity of Gyeongju National Park by objective surveying and analysing the flora distributed in Mt. Gumi District, Gyeongju National Park, South Korea. The flora of Mt. Gumi were surmmarized as 476 taxa including 97 families, 297 genera, 419 species, 3 subspecies, 46 varieties and 8 forms. The rare plants were 6 taxa such as Aristolochia contorta, Paeonia lactiflora var. trichocarpa, Potentilla discolor, Berchemia berchemiaefolia, Trigonotis icumae and Iris odaesanensis. The Korean endemic plants were 9 taxa such as Carpinus laxiflora, Pseudostellaria coreana, Philadelphus schrenkii, Indigofera koreana, Lespedeza maritima, Vicia chosenensis, Galium koreanum, Lonicera subsessilis and Weigela subsessilis. The specific plants by floristic region were 38 taxa such as Salix chaenomeloides(I), Hylomecon vernalis (I), Oxalis obtriangulata (I), Viola orientalis(II), Adoxa moschatellina (II), Cirsium chanroenicum (II), Vitex negundo var. incisa (III) and so forth. The naturalized plants were 36 taxa such as Fallopia dumetorum, Chenopodium album, Lepidium virginicum, Amorpha fruticosa, Euphorbia supina, Carduus crispus, Erigeron strigosus, Festuca myuros and so forth. The invasive aline plant was Aster pilosus. The target plants adaptable to climate change were 8 taxa such as Artemisia rubripes, Carpesium macrocephalum and so forth.

Simulated erosion using soils from vegetated slopes in the Jiufeng Mountains, China

The effects of rainfall intensity, slope gradient and vegetation cover on the intensity of runoff and rate of soil erosion were examined with simulated rainfall. All five affected soil erosion in experimental soil boxes containing Vitex negundo var. heterophylla (VN), VN with litter (VN-L), Broussonetia papyrifera (BP), BP with litter (BP-L), and a control with bare land (BL). The presence of the vegetation and litter layers significantly reduced the rates of sediment yields, the mean rate of sediment yield values of BP-L, BP, VN-L, VN and BL were 2.873g/min, 11.264g/min, 4.220g/min, 16.781g/min and 21.594g/min, respectively. The mean rates of sediment yield increased linearly with increases of rainfall intensity and slope gradient, but not beyond a certain gradient. B. papyrifera reduced sediments by 6.24 and 25.55% more than V. negundo var. heterophylla with and without litter layers, respectively. The rate of sediment yield was positively and linearly correlated with runoff shear force, with rates increasing quickly in VN, and the critical runoff shear force of BP was 0.8282N/m2, and VN was 0.2098N/m2. The results of this study will help to determine appropriate methods for reducing soil erosion.

Anti-inflammatory Ursane- and Oleanane-Type Triterpenoids from Vitex negundo var. cannabifolia

Six new polyoxygenated triterpenoids, cannabifolins A-F (1-6), and eight known triterpenoids, 7-14, were isolated from the leaves of Vitex negundo var. cannabifolia. The absolute configuration of cannabifolin A (1) was determined by single-crystal X-ray crystallographic analysis. Compounds 1 and 2 represent a class of rare natural pentacyclic triterpenoids bearing cis-fused C/D rings and are the first examples of 12,19-epoxy ursane- and oleanane-type triterpenoids. Compounds 3, 7, 8, and 14 exhibited inhibition of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages with IC50 values in the range 24.9-40.5 μM.

Carbon sequestration effects of shrublands in Three-North Shelterbelt Forest region, China

Three-North Shelterbelt Forest (TSF) program, is one of six key forestry programs and has a 73-year construction period, from 1978 to 2050. Quantitative analysis of the carbon sequestration of shrubs in this region is important for understanding the overall function of carbon sequestration of the forest and other terrestrial ecosystems in China. This study investigated the distribution area of shrubland in the TSF region based on remote sensing images in 1978 and 2008, and calculated the carbon density of shrubland in combination with the field investigation and previous data from published papers. The carbon sequestration quantity and rate from 1978 to 2008 was analyzed for four sub-regions and different types of shrubs in the TSF region. The results revealed that: 1) The area of shrubland in the study area and its four sub-regions increased during the past thirty years. The area of shrubland for the whole region in 2008 was 1.2 × 107 ha, 72.8% larger than that in 1978. The Inner Mongolia-Xinjiang Sub-region was the largest shrubland distribution area, while the highest coverage rate was found in the North China Sub-region. 2) In decreasing order of their carbon sequestration, the four types of shrubs considered in this study were Hippophae rhamnoides, Caragana spp., Haloxylon ammodendron and Vitex negundo var. heterophylla. The carbon sequestration of H. rhamnoides, with a maximum mean carbon density of 16.5 Mg C/ha, was significantly higher than that of the other three species. 3) The total carbon sequestration of shrubland in the study region was 4.5 × 107 Mg C with a mean annual carbon sequestration of 1.5 × 106 Mg C. The carbon density in the four sub-regions decreased in the following order: the Loess Plateau Sub-region, the North China Sub-region, the Northeast China Sub-region and the Inner Mongolia-Xinjiang Sub-region. The paucity of studies and data availability on the large-scale carbon sequestration of shrub species suggests this study provides a baseline reference for future research in this area.

경주국립공원 서악 지구의 관속식물상

The purpose of this study is to offer the raw data for establishing the management and restoration plan by objective surveying and analysing the flora distributed in Seoak District, Gyeongju National Park, Korea. The flora summarized as 411 taxa including 92 families, 285 genera, 363 species, 2 subspecies, 41 varieties and 5 forms. The rare plants designated by Korea Forest Service were 2 taxa including Exochorda serratifolia and Potentilla discolor. The Korean endemic plants were 3 taxa including Philadelphus schrenkii, Lespedeza maritima and Weigela subsessilis. The specific plants by floristic region were 16 taxa including Asplenium sarelii, Pyrrosia petiolosa, Vitex negundo var. incisa and so forth. The target plants adaptable to climate change were 2 taxa including Lespedeza maritima and Carpesium macrocephalum, and the plants with approval for delivering oversea were 4 taxa including Exochorda serratifolia, Glycine soja, Lespedeza maritima and Weigela subsessilis. The naturalized plants were 51 taxa including Phytolacca americana, Viola papilionacea, Lamium purpureum and so forth. The invasive alien plants were 3 taxa including Ambrosia artemisiifolia, Aster pilosus and Lactuca scariola. NI(Naturalized Index) was 12.4% of all 411 taxa of surveyed flora in this study and UI(Urbanized Index) was 15.9% of all 321 taxa of naturalized plants in Korea. Potentilla discolor in rare plant, Philadelphus schrenkii in endemic plant and Dictamnus dasycarpus in specific plant were established the conservation plan. Whereas, invasive alien plants such as Ambrosia artemisiifolia, Aster pilosus and Lactuca scariola should be removed as soon as possible. The damaged sites in Seoak District were divided between wildfire area and farmland. To restore a forest fire site, we will have to apply a natural renewal and community planting. In case of farmland, we will have to do ecological planting using native species and constrcut a forest wetland.

Antioxidant lignans from the seeds of Vitex negundo var. cannabifolia

A new phenyldihydronaphthalene-type lignan, vitexdoin F (1), along with 22 known lignan derivatives (2–23) was isolated from the seeds of Vitex negundo var. cannabifolia. Their structures were established by comprehensive 1D and 2D NMR spectroscopic analyses. The antioxidant activities of these lignans were evaluated through 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assays, and 16 of these isolates exhibited obvious radical-scavenging effect on the stable-free radical, DPPH.

Comparative Study on Antimicrobial Activity of <i>Vitex negundo</i> var. <i>negundo</i> and <i>Vitex negundo</i> var. <i>purpurascens</i>

The present study was conducted with an aim of determining antimicrobial activity of Vitex negundo var. negund o (Vnvn) and Vitex negundo var. purpurascens (Vnvp).The powdered leaf materials of both varieties were extracted using methanol in soxhlet assembly. The content of total phenolics and flavonoids were estimated by Folin-Ciocalteau reagent and Aluminium chloride colorimetric estimation method respectively. Antibacterial activity of extracts was determined against five drug resistant urinary tract pathogens by agar well diffusion assay. Poisoned food technique was performed to determine antifungal effect of extracts. The extracts caused concentration dependent inhibition of urinary tract isolates. Marked antibacterial effect was shown by extract of Vnvp. Among bacteria, Staphylococcus aureus and Klebsiella pneumoniae were inhibited to high and least extent respectively by extracts. The extracts were effective in inhibiting test fungi as revealed by reduction in mycelial growth in plates poisoned with extracts. Here also, high inhibitory activity was observed in case of extract of Vnvp. Among fungi, Helminthosporium sp., Alternaria sp., and C. capsici displayed similar susceptibility to both extracts at concentration 1mg/ml. Aspergillus flavus was inhibited to least extent by extracts. Phytoconstituents viz., tannins, alkaloids, flavonoids, saponins, steroids and glycosides were detected in extract of both Vnvn and Vnvp. The total phenolic and flavonoid contents were high in extract of Vnvp. The extracts were effective against bacteria and fungi. The presence of high phenolic and flavonoid content could be ascribed to the marked inhibitory activities of the extract of Vnvp.

Soil greenhouse gas fluxes from different tree species on Taihang Mountain, North China

Abstract. The objectives of this study were to investigate seasonal variation of greenhouse gas fluxes from soils on sites dominated by plantation (Robinia pseudoacacia, Punica granatum, and Ziziphus jujube) and natural regenerated forests (Vitex negundo var. heterophylla, Leptodermis oblonga, and Bothriochloa ischcemum), and to identify how tree species, litter exclusion, and soil properties (soil temperature, soil moisture, soil organic carbon, total N, soil bulk density, and soil pH) explained the temporal and spatial variation in soil greenhouse gas fluxes. Fluxes of greenhouse gases were measured using static chamber and gas chromatography techniques. Six static chambers were randomly installed in each tree species. Three chambers were randomly designated to measure the impacts of surface litter exclusion, and the remaining three were used as a control. Field measurements were conducted biweekly from May 2010 to April 2012. Soil CO2 emissions from all tree species were significantly affected by soil temperature, soil moisture, and their interaction. Driven by the seasonality of temperature and precipitation, soil CO2 emissions demonstrated a clear seasonal pattern, with fluxes significantly higher during the rainy season than during the dry season. Soil CH4 and N2O fluxes were not significantly correlated with soil temperature, soil moisture, or their interaction, and no significant seasonal differences were detected. Soil organic carbon and total N were significantly positively correlated with CO2 and N2O fluxes. Soil bulk density was significantly negatively correlated with CO2 and N2O fluxes. Soil pH was not correlated with CO2 and N2O emissions. Soil CH4 fluxes did not display pronounced dependency on soil organic carbon, total N, soil bulk density, and soil pH. Removal of surface litter significantly decreased in CO2 emissions and CH4 uptakes. Soils in six tree species acted as sinks for atmospheric CH4. With the exception of Ziziphus jujube, soils in all tree species acted as sinks for atmospheric N2O. Tree species had a significant effect on CO2 and N2O releases but not on CH4 uptake. The lower net global warming potential in natural regenerated vegetation suggested that natural regenerated vegetation were more desirable plant species in reducing global warming.

Winter Soil CO2 Flux from Different Mid-Latitude Sites from Middle Taihang Mountain in North China

Winter soil respiration is a very important component of the annual soil carbon flux in some ecosystems. We hypothesized that, with all other factors being equal, shorter winter SR result in reduced contribution to annual soil C flux. In this study, the contribution of winter soil respiration to annual soil respiration was measured for three sites (grassland: dominated by Artemisia sacrorum, Bothriochloa ischaemum and Themeda japonica; shrubland: dominated by Vitex negundo var. heterophylla; plantation: dominated by Populus tomatosa) in a mountainous area of north China. Diurnal and intra-annual soil CO2 flux patterns were consistent among different sites, with the maximum soil respiration rates at 12∶00 or 14∶00, and in July or August. The lowest respiration rates were seen in February. Mean soil respiration rates ranged from 0.26 to 0.45 µmol m−2 s−1 in the winter (December to February), and between 2.38 to 3.16 µmol m−2 s−1 during the growing season (May-September). The winter soil carbon flux was 24.6 to 42.8 g C m−2, which contributed 4.8 to 7.1% of the annual soil carbon flux. Based on exponential functions, soil temperature explained 73.8 to 91.8% of the within year variability in soil respiration rates. The Q10 values of SR against ST at 10 cm ranged from 3.60 to 4.90 among different sites. In addition, the equation between soil respiration and soil temperature for the growing season was used to calculate the “modeled” annual soil carbon flux based on the actual measured soil temperature. The “measured” annual value was significantly higher than the “modeled” annual value. Our results suggest that winter soil respiration plays a significant role in annual soil carbon balance, and should not be neglected when soil ecosystems are assessed as either sinks or sources of atmospheric CO2.

Soil respiration response in different vegetation types at Mount Taihang, China

Temperature response of soil respiration depends on the sensitivity and adaptability of soil respiration (SR) for the variation of soil temperature, which will directly influence the terrestrial carbon cycling and extent prediction of global warming. The diurnal and seasonal variations in the temperature response of SR were assessed through continuous measurement during the June 2012–May 2013 with an automated chamber system under three vegetation types (Robinia pseudoacacia, RP; Vitex negundo var. Heterophylla, VN; Artemisia sacrorum, AS) in the hilly region of Mount Taihang, China. Our results indicated that SR exhibited significant seasonal variations in the RP, VN and AS sites (0.15–5.14, 0.14–4.51 and 0.22–5.28μmolm−2s−1). Due to the adaptability for the variation of soil temperature, SR peaked in Aug 2012 and bottomed in Apr 2013, and the adaptability will weaken the relationship between SR and temperature. Because of the differences of plant physiology and environment conditions, temperature sensitivity of soil respiration (Q10) varied among vegetation types. Meanwhile, because of exempted from seasonal complicated factors, average daily Q10 values of the RP, VN and AS sites (1.86, 1.35 and 1.53) were all smaller than the values of annual Q10 (2.12, 3.32 and 2.61), and might better reflect the biological sensitivity of respiration to temperature. Q10 exhibited a strong seasonal variation pattern, and decreased with increasing soil temperature. This result indicates that low temperature may be more important to carbon cycling than higher temperature based on soil respiration results. The study area had low soil respiration rates, enhancing the long term C accumulation in the context of global warming. The seasonal variation of Q10 was primarily driven by soil temperature while soil moisture had little influence on the dynamic for each site based on annual scales. However, due to the complicated relation between soil properties and SR, Q10 value derived from diurnal and seasonal patterns of SR should be used with extreme caution when estimating carbon balance of terrestrial ecosystem.

衡阳紫色土丘陵坡地植被恢复阶段土壤特性的演变

PDF HTML阅读 XML下载 导出引用 引用提醒 衡阳紫色土丘陵坡地植被恢复阶段土壤特性的演变 DOI: 10.5846/stxb201301030012 作者: 作者单位: 湖南环境生物职业技术学院,湖南农业大学生物科学技术学院,湖南环境生物职业技术学院,湖南环境生物职业技术学院,湖南环境生物职业技术学院,湖南环境生物职业技术学院,湖南环境生物职业技术学院 作者简介: 通讯作者: 中图分类号: S154.2；S155.2 基金项目: 湖南省重点项目（62020608001）；湖南省科技厅项目（S2006N332）；湖南省教育厅科学研究项目（12C1057）；湖南省普通高校优秀青年骨干教师培养对象资助项目；湖南环境生物职业技术学院南岳学者基金项目（湘环职院[2012]4号）资助 Changes of soil properties in re-vegetation stages on sloping-land with purple soils in hengyang of Hunan Province, South-central China Author: Affiliation: Hunan Environmental-Biological Polytechnic College,a College of Landscape Architecture,bCentre of Practice and Train,Hengyang,,,,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:采用空间代替时间序列方法，对衡阳紫色土丘陵坡地不同恢复阶段的土壤理化性质、土壤微生物数量、土壤微生物学性质和主要酶活性特征以及它们之间的相互关系进行研究。结果表明：不同恢复阶段土壤理化特征存在明显差异，从狗尾草群落阶段（Ⅰ）、紫薇-狗尾草群落阶段（Ⅱ）、牡荆+剌槐群落阶段（Ⅲ）到枫香+苦楝-牡荆群落阶段（Ⅳ），0-40cm土壤含水量、容重、非毛管孔隙度、孔隙比、大于0.25mm水稳性团聚体含量、有机碳（SOC）、全氮（TN）、碱解氮（AN）与速效磷（AP）显著增加，土壤容重显著减小，土壤pH值逐渐减小，土壤全磷（TP）、全钾（TK）与速效钾（AK）其差异变化不大，土壤理化特征的差异引起土壤微生物数量、微生物学性质与土壤酶活性的变化；不同恢复阶段土壤微生物总数显著增加，其中细菌数量显著增加，而真菌与放线菌数量显著减少；不同恢复阶段土壤基础呼吸（SBR）、土壤微生物量碳（SMBC）、土壤微生物量氮（SMBN）、土壤微生物量磷（SMBP）、土壤微生物熵（Cmic/Corg）显著增加，而代谢熵或呼吸熵（qCO2）显著减小，碳氮比（C/N）逐渐减小；不同恢复阶段均显著地增加了脲酶（URE）、蔗糖酶（INV）与磷酸酶（APE）的活性；土壤理化性状、土壤微生物数量、土壤微生物学性质与土壤酶活性之间存在密切的相关性。 Abstract:The purpose of the paper was to study the purple soil's physico-chemical characteristics, microbial populations, microbial properties, enzyme activities, and the relationships between them in different stages of re-vegetation on sloping-land in Hengyang of Hunan Province, South-central China. We took soils of 0-40cm depth in typical areas in Setaria viridi community stage (Ⅰ); Lagerstroemia indica-Setaria viridi community stage (Ⅱ); Vitex negundo var. cannabifolia+Robinia pseudoacacia community stage (Ⅲ); and Liquidamdar formosana+Melia azedarach-Vitex negundo var. cannabifolia community stage (Ⅳ) as our test objects by using the space series to replace time courses.The results showed that: (1) From Ⅰ, Ⅱ, Ⅲ to Ⅳ, the soil water content, total soil porosity, ratio of non-capillary porosity to capillary porosity, >0.25mm water stable aggregates content, SOC (Soil Organic C), TN (Total N), AN (Available N) and AP (Available P) increased significantly. In contrast, soil bulk density decreased significantly, pH decreased slightly, and there were no significant differences in TP (Total P), TK (Total K) and AK (Available K). The changes in the number of soil microbes, microbial properties and the soil enzyme activities have resulted from the differences in the soil physico-chemical characteristics. (2) The number of soil microbes increased significantly, with a significant increase in the number of bacteria, but the numbers of fungi and actiomycetes decreased significantly in the process of the succession. (3) The SBR (Soil Base Respiration), SMBC (Soil Microbial Biomass C), SMBN (Soil Microbial Biomass N), SMBP (Soil Microbial Biomass P) and Cmin/Corg increased significantly. The qCO2 decreased significantly, and C/N decreased, with no significant difference in the process of succession. The activities of URE (Urease), INV (Invertase) and APE (Alkaline phosphatase) significantly increased in the process of the succession. (4) There were close correlations among the soil physico-chemical characteristics, the number of soil microbes, the soil microbial properties and the soil enzyme activities. This study will, to some degree, enrich the restoration ecology of this area and provide a theoretical basis for the re-vegetation and reconstruction of ecosystems on sloping land with purple soils in Hengyang of Hunan Province, South-central China. 参考文献 相似文献 引证文献

경상북도 경주시 금곡산에 분포하는 관속식물상

The purpose of this study is to collect the raw data for conservation of plant ecosystem by surveying and analysing the flora of Mt. Geumgok located in Gyeongju-si, Gyeongsangbuk-do, Korea. The flora were summarized as 453 taxa including 91 families, 298 genera, 397 species, 4 subspecies, 46 varieties and 6 forms. The rare plants designated by Korea Forest Service were 3 taxa such as Eranthis byunsanensis B.Y.Sun, Potentilla discolor Bunge and Iris odaesanensis Y.N.Lee. The Korean endemic plants were 6 taxa such as Carpinus laxiflora (Siebold & Zucc.) Blume, Eranthis byunsanensis B.Y.Sun, Philadelphus schrenkii Rupr., Lespedeza maritima Nakai, Vicia chosenensis Ohwi and Weigela subsessilis (Nakai) L.H.Bailey. The specific plants by floristic region were 36 taxa such as Pinus koraiensis Siebold & Zucc., Salix chaenomeloides Kimura, Anemone raddeana Regel, Chloranthus japonicus Siebold, Euphorbia pekinensis Rupr., Ilex macropoda Miq., Ajuga multiflora Bunge, Saussurea odontolepis Sch.Bip. ex Herd, Viola orientalis (Maxim.) W.Becker, Betula davurica Pall., Vitex negundo var. incisa (Lam.) C.B.Clarke and Cimicifuga heracleifolia Kom.. The naturalized plants were 36 taxa such as Fallopia dumetorum (L.) Holub, Lepidium apetalum Willd., Robinia pseudoacacia L., Trifolium repens L., Euphorbia supina Raf., Ipomoea purpurea Roth, Veronica persica Poir., Bidens pilosa L., Carduus crispus L., Xanthium canadense Mill., Bromus unioloides H.B.K. and Festuca arundinacea Schreb.. The invasive alien plants were 2 taxa such as Ambrosia artemisiifolia L. and Aster pilosus Willd.. The ratios of the urbanized index(UI), the naturalized index(NI) and the disturbed index(DI) were 11.2%, 7.9% and 18.2% each.

Pollen Analysis of Natural Honeys from the Central Region of Shanxi, North China

Based on qualitative and quantitative melissopalynological analyses, 19 Chinese honeys were classified by botanical origin to determine their floral sources. The honey samples were collected during 2010–2011 from the central region of Shanxi Province, North China. A diverse spectrum of 61 pollen types from 37 families was identified. Fourteen samples were classified as unifloral, whereas the remaining samples were multifloral. Bee-favoured families (occurring in more than 50% of the samples) included Caprifoliaceae (found in 10 samples), Laminaceae (10), Brassicaceae (12), Rosaceae (12), Moraceae (13), Rhamnaceae (15), Asteraceae (17), and Fabaceae (19). In the unifloral honeys, the predominant pollen types were Ziziphus jujuba (in 5 samples), Robinia pseudoacacia (3), Vitex negundo var. heterophylla (2), Sophora japonica (1), Ailanthus altissima (1), Asteraceae type (1), and Fabaceae type (1). The absolute pollen count (i.e., the number of pollen grains per 10 g honey sample) suggested that 13 samples belonged to Group I (<20,000 pollen grains), 4 to Group II (20,000–100,000), and 2 to Group III (100,000–500,000). The dominance of unifloral honeys without toxic pollen grains and the low value of the HDE/P ratio (i.e., honey dew elements/pollen grains from nectariferous plants) indicated that the honey samples are of good quality and suitable for human consumption.

Morphological response of Vitex negundo var. heterophylla and Ziziphus jujuba var. spinosa to the combined impact of drought and shade

Light and soil moisture availability are two important abiotic factors influencing plant growth in an agroforestry system. Different soil moisture and light treatments were applied to examine the combined impact of drought and shade on the morphological plasticity of Vitex negundo var. heterophylla (Chinese chastetree) and Ziziphus jujuba var. spinosa (Spine jujube). We found that the interaction of light and soil moisture was orthogonal in the two species. V. negundo captured irradiance efficiently with relatively long petiole and petiolule, while Z. jujuba maintained higher branches to absorb light than V. negundo. Compared to the seedlings under full sunlight, the palmately compound leaves of V. negundo under low light showed larger specific leaf area (SLA), lower ratio of leaflet length to width and higher leaf mass ratio (leaf biomass to total biomass); in contrast, the simple leaves of Z. jujuba under low light showed larger SLA and ratio of leaf length to petiole length. In both species, drought reduced the branch number, mean internode length of stem, and increased root mass ratio (root biomass to total biomass), but leaf morphology showed little variation to the decreased soil moisture. Between the two species, V. negundo is more shade-tolerant, while Z. jujuba is more drought-tolerant. In an alley cropping system, the spacing can be smaller in the V. negundo-crop system than the Z. jujuba-crop system when soil moisture is adequate. However, the V. negundo-crop system should be managed with more caution under the soil moisture limited conditions.