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1.
《American anthropologist》1955,57(1):156-159
Book reviewed in this article:
Vassbaering i Norge (Water Carrying in Norway)
Juletreet i Norge (The Christmas Tree in Norway)  相似文献   

2.
BOOK REVIEWS     
《植被学杂志》1997,8(6):889-890
Book reviewed in this article: Arroyo, M.T.K., Donoso, C., Murúa, R.E., Pisano, E.E., Schlatter, R.P. & Serey, A. 1996. Toward an ecologically sustainable forestry project: concepts, analysis and recommendations. Short reviews Given, David R. 1994. Principles and practice of plant conservation. Fremstad, Eli. 1997. Vegetasjonstyper i Norge. Hermy, Martin & De Blust, Geert (editors). 1996. Punten en lijnen in het landschap. Vernet, J.-L. 1997. L'homme et la forêt méditer-ranéenne de la préhistoire à nos jours. Grabherr, Georg. 1997. Farbatlas Ökosysteme der Erde.  相似文献   

3.
Abstract. The background of the Nordic Vegetation Survey is outlined and the concepts for this international collaboration project are reviewed. The project includes, so far, institutions in Denmark, Faeroes, Finland, Norway and Sweden. We are setting up a common basis for a vegetation database, with a Nordic species list, exchange of data and joint revisions of important Nordic vegetation types. Progress in the Nordic Vegetation Survey is described and the future perspectives indicated.  相似文献   

4.
BOOK REVIEWS     
Book reviewed in this issue. Okland, R. H. Vegetation Ecology: Theory, Methods, and Application to Fennoscandia . 1990. 233 pp. Som-merfeltia Supplement 1, Botanical Gardens and Museum, University of Oslo, Oslo, Norway. ISBN 82–7420–006–3. Price: NOK 180.  相似文献   

5.
Environmental reservoirs of glycopeptide-resistant enterococci (GRE) in Norway have been linked to former growth promoting use of the glycopeptide avoparcin in poultry production. We have examined the prevalence of fecal GRE in poultry and poultry farmers 3 to 8 years after the Norwegian avoparcin ban in 1995 and performed molecular analyses of the GRE population. Fecal samples from poultry farmers and their flocks on 29 previously avoparcin-exposed farms were collected on five occasions during the study period (1998 to 2003). All flocks (100%) were GRE positive in 1998. Throughout the study period, 78.5% of the poultry samples were GRE positive. Glycopeptide-resistant Enterococcus faecium (GREF) was isolated from 27.6% of the farmer samples in 1998 and from 27.8% of the samples collected between 1998 and 2003. The prevalence of fecal GRE in poultry declined significantly during the study period, but prevalence in samples from the farmers did not decline. PCR analysis revealed a specific Tn1546-plasmid junction fragment in 93.9% of E. faecium isolates. A putative postsegregation killing (PSK) system linked to Tn1546 was detected in 97.1% of the isolates examined. Multilocus sequence typing of glycopeptide-susceptible (n = 10) and -resistant (n = 10) E. faecium isolates from humans (n = 10) and poultry (n = 10) on two farms displayed 17 different sequence types. The study confirms the continuing persistence of a widespread common plasmid-mediated vanA-pRE25-PSK element within a heterogeneous GRE population on Norwegian poultry farms 8 years after the avoparcin ban. Moreover, it suggests an important role of PSK systems in the maintenance of antimicrobial resistance determinants in reservoirs without apparent antimicrobial selection.  相似文献   

6.
植被志(vegegraphy)是基于植被调查资料, 全面记叙植被的群落外貌、种类组成、结构和功能、生境条件, 以及地理分布等特征, 并对同类植被进行归纳和总结的志书。“植被志”的英文译为“vegegraphy”, 是本文的新造词, 它是由“vegetation”的词头“vege-”和英文后缀“-graphy” (记叙之意)组成的合成词。《中国植被志》的研编是一项时间紧迫、内容复杂、工作量浩繁的重大科学工程。它的完成将极大提升中国植被科学和生态学的研究水平, 并为中国植被资源的合理利用、生物多样性保护及生态环境治理等提供不可或缺的基础资料。本文首先简述了植被的基本特征(主要包括外貌特征、种类组成、群落结构以及动态变化等)和国内外植被调查的进展情况, 简要回顾了中国植被分类系统的研究历史, 并对以往的分类系统进行了若干修订。在此基础上, 着重讨论并提出了《中国植被志》卷册编排体系和用于《中国植被志》研编的植被类型划分方案。在对植被分类系统的修订方面, 主要对高级分类单位及相对应的英文名称进行了讨论和修订。按照本文修订的分类系统, 中国植被的分类单位及其对应的英文名称分别是: 植被型组(Vegetation Formation Group)、植被型(Vegetation Formation)和植被亚型(Vegetation Subformation)、群系组(Alliance Group)、群系(Alliance)和亚群系(Suballiance)、群丛组(Association Group)以及群丛(Association)。在植被型组中, 划分为9类: 森林、灌丛、草本植被、荒漠、高山冻原与稀疏植被、沼泽与水生植被、农业植被、城市植被及无植被地段。关于《中国植被志》的卷册编排和“植被类型”划分, 首先按高级分类单位——植被型划分相应的“卷”; 在此框架下, 模糊“植被亚型”、“群系组”和“群系”的概念, 确定“植被类型” (Vegetation type), 并将其作为植被志各卷中的“册”。这样处理不仅保证了研编工作的可操作性, 也保持了同一卷册中特定植被类型的完整性。《中国植被志》编排体系中的“植被类型”的划分很重要, 它是指具有相同建群种及相同优势类群(如种、属)的植被组合, 但它不是严格意义上的植被分类单位。“植被类型”的划分遵循“优势类群及生活型的同一性, 生境条件的相对重要性, 植被特征及用途的差异性, 以及突出植被志的应用性”等原则。按该编排体系, 《中国植被志》将由48卷约110册组成。  相似文献   

7.
The goal of this study was to determine if selected biochemical, structural and spectral properties of Norway spruce needles are influenced by the azimuth orientation of the branch. Three youngest needle age classes from 20 mature (100 years old or older) Norway spruce trees were sampled from upper branches of the sunlit production crown part from each of the 4 cardinal azimuth orientations. Photosynthetic pigments, soluble phenolic compounds and selected spectral and structural characteristics were determined for each needle age class. The content of photosynthetic pigments and soluble phenolic compounds did not differ among needles from different azimuth-oriented branches, nor did the optical reflectance indices Normalized Difference Vegetation Index (NDVI), Transformed Chlorophyll Absorption in Reflectance Index (TCARI)/Optimized Soil-Adjusted Vegetation Index (OSAVI), Red Edge Inflection Point (REIP) and Landsat Thematic Mapper bands 5 and 4 (TM5/TM4). No variation in volume properties, tissue volume proportions and cross-section shape characteristics of 3rd-year needles rejected our hypothesis that there would be variation in needle structural properties according to the azimuth orientation of branches. Consequently, we concluded that a random sampling of similar-aged needles within the sunlit production crown part may be used to study biochemical or structural and spectral needle properties of a mature Norway spruce growing in forest stands without a significant slope. In addition, the results obtained from a branch of one azimuth orientation should be representative for the whole sunlit portion of the crown. Consequences of these findings for Norway spruce health monitoring using remote sensing techniques are discussed.  相似文献   

8.
 To gain information on the extent and nature of genetic variation in Elymus alaskanus, levels and distribution of genetic variation were assessed within and among 13 populations originating from Iceland, Norway, Sweden and Russia using allozymes. The results showed that four (30.7%) of the 13 loci were polymorphic within the species, while the mean percentage of polymorphic loci within the populations was 1.9%. The mean number of alleles per locus for the species was 1.8 and 1.02 across the populations. Genetic diversity at the species level was low (H es=0.135), and mean population diversity was notably lower (H ep=0.005). A high degree of genetic differentiation was observed among populations. The salient points emerging from this study are: (1) statistically significant differences were found in allele frequencies among populations for every polymorphic locus (P<0.001), (2) the high mean coefficient of gene differentiation (G ST) showed that 95% of the total allozyme variation was attributable to differences among populations, and (3) relatively high genetic distances between the populations were obtained (mean D=0.16). The Norwegian populations had the highest genetic diversity as compared with the other populations. Geographical comparisons revealed three different groups of populations clearly differentiated, i.e. Scandinavia (Norway and Sweden), Iceland and Russia. Cluster and principal coordinates analyses revealed the same genetic patterns of relationships among populations. Generally, this study indicates that E. alaskanus contains low allozymic variation in its populations. The implications of these results for the conservation of the species are discussed. Received: 23 October 1998 / Accepted: 19 December 1998  相似文献   

9.
Book Reviews     
Abstract. van der Maarel, E. (ed.) 2005. Vegetation ecology. 395 pp. Blackwell Publishing, Maiden, Oxford & Carlton. ISBN 0‐632‐05761‐0 (paperback). Price: GBP 34.99.  相似文献   

10.
Wild et al. (2014, Journal of Vegetation Science 25: 1327–1340) document persistent effects of the spatial distribution of canopy trees on the distribution of regeneration following stand‐replacing disturbance in montane Norway spruce forests. The authors suggest a simple physical process for these legacy effects – the accumulation of winter‐dispersed seeds in ‘tree‐wells’ with lower snow depth around the trunks of living and recently dead trees.  相似文献   

11.
Artificial insemination (AI) in sheep is currently limited by the poor fertility obtained following non-surgical intracervical insemination of frozen-thawed semen. An exception to this general finding is the non-return rate of around 58% reported for large scale on-farm AI in Norway. The objective of the present study was to determine if similar results could be obtained under Irish conditions. Comparisons were made between semen collected, and frozen, from rams in Norway (NOR) and Ireland (IRL). The effects of synchronisation and inseminator were also examined. Parous ewes (n=297) of various breed types were inseminated to a natural (N) or synchronised (S) oestrus with either fresh (from Irish rams) or frozen-thawed (IRL and NOR) semen. Ewes were randomly assigned, within breed, to the following treatment groups: (i) Fresh-N: n=28, (ii) Fresh-S: n=30, (iii) IRL-N: n=62, (iv) IRL-S: n=50, (v) NOR-N: n=68, (vi) NOR-S: n=59. Within each group, ewes were inseminated by an experienced Norwegian or by an Irish inseminator. Pregnancy rate did not differ significantly between ewes inseminated to a natural or synchronised oestrus nor between Norwegian and Irish frozen semen. The proportion of ewes pregnant after insemination with fresh semen was 0.82 and 0.70 (treatments i and ii) compared with 0.40, 0.52, 0.34 and 0.37 (treatments (iii)-(vi)) for frozen semen (P<0.001). Corresponding litter sizes (+/-S.E.), adjusted for ovulation rate, were 2.9+/-0.22, 3.3+/-0.23, 2.2+/-0.21, 1.7+/-0.21, 2.2+/-0.21 and 2.1+/-0.21 (fresh versus frozen; P<0.001). There was an interaction between semen type (fresh or frozen) and oestrus type (N or S) for litter size due to an increased adverse effect of frozen semen on litter size in synchronised ewes (P<0.05). Pregnancy rate was significantly influenced by breed of ewe (P<0.01) and inseminator (P<0.05). These results suggest that ewe breed may be a critical determinant of the potential for the exploitation of cervical insemination of frozen-thawed semen in sheep breeding programmes.  相似文献   

12.
Six taxa, representing five species of Entoloma (Fr.) Kumm. subgen. Pouzaromyces (Pilat) Moser emend. Noordel. are described from Norway, of which four are new to the country, viz., E. dysthales (Peck) Sacc, E. dysthaloides Noordel., E. araneosum (Quel.) Moser i.fulvostrigosum (Berk. & Br.) Noordel., and E. versatilis (Fr.) Moser.  相似文献   

13.
中国东北地区主要植被类型NDVI变化与气候因子的关系   总被引:38,自引:2,他引:38  
张军  葛剑平  国庆喜 《生态学报》2001,21(4):522-527
利用1982~1992年时间序列的NOAA/AVHRR8km×8km分辨率的归一化植被指数(Normalizeddifferencevegetationindex,NDVI),将东经120°~135°、北纬40°~55°区域的土地覆盖类型分为10类。然后研究了各类型的NDVI年平均值的变化规律。结合该地区的19个气象站1982~1992年的年平均气温、年最高温度、年最低温度、年降水量和年相对湿度研究了各类型NDVI年平均值的变化与气候因子之间的关系,进一步阐明了气候因子是NDVI动态变化的主要原因。  相似文献   

14.
Spatial patterns of herbaceous biodiversity in Mongolia steppe were examined and explained with biotic and abiotic factors including climate, livestock grazing, and fire disturbance. Vegetation data were collected from 63 sites across different steppe types (i.e., semi-desert, typical, and forb steppes) in 2012 and 2013. Three categorical (three steppe types, burned or not, grazed or not) and three continuous variables (precipitation, vegetation productivity, site-camp distance) were developed from national climate and GIS database of Mongolia and two satellite sensor products: Tropical Rainfall Measuring Mission (TRMM) precipitation and June-to-August accumulated Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVIJJA). The prescribed factors were utilized to examine single- and multiple-factor effects on biodiversity and community structure, by using correlation, stepwise multiple regression analysis, and ordination. Our results indicate the positive effect of precipitation and fire but negative effect of grazing on biodiversity in our study region. Localized herding effect was recognized to areas less than 1.5 km away from the herder's camp sites. Fire, precipitation and productivity (NDVIJJA) were identified as important factors affecting biodiversity of remote regions. Based on the results, we infer that pastureland biodiversity of Mongolia is controlled by region-scale variations of climate and vegetation productivity, but locally modified by intensive livestock grazing pressure with different grazing sensitivity for different steppe types.  相似文献   

15.
A population of yellow starthistle (Centaurea solstitialis L.) near Dayton, Washington developed herbicide resistance in response to repeated applications of picloram and other auxin-type herbicides. Laboratory and field experiments were conducted in 1998 to determine host acceptability and suitability of this herbicide-resistant yellow starthistle population to the biological control weevil Eustenopus villosus (Boheman) (Coleoptera: Curculionidae). In choice and no-choice feeding and oviposition experiments using excised buds, the weevil did not demonstrate a consistent preference for either herbicide-resistant (R) or -susceptible (S) yellow starthistle. When caged on buds of intact plants, the E. villosus feeding rate of 97% did not differ between R and S types. Host plant suitability, measured as larval damage and development to adult weevils, was equivalent in R and S types, with weevils maturing in 46% of the R and in 32% of the S capitula bearing oviposition scars. The number of viable achenes per capitulum was reduced by 87% due to larval feeding, with no difference between R and S types. Observations at the field site where resistance was found revealed oviposition scars on 78% of the late-bud-stage capitula on 23 June 1998 and 73% of the flowering and postflowering capitula on 15 August 1998. Selection for herbicide resistance has not created host incompatibility for E. villosus nor reduced the effectiveness of E. villosus as a biological control agent.  相似文献   

16.
A massive ice storm hit northeastern North America in 1998, dropping more than 100 mm of freezing rain at its epicenter in southern Quebec, Canada. There has been extensive study of which trees and areas received the most damage, but the biodiversity consequences of this damage at landscape scales have not received much attention. We assessed the effectiveness of seven remotely sensed vegetation indices—Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index, Difference Vegetation Index, Renormalized Difference Vegetation Index, Atmospherically Resistant Vegetation Index, Green Normalized Difference Vegetation Index and Visible Atmospheric Resistant Index—for modeling the coarse woody debris (CWD) influx in an old growth forest reserve at the storm’s epicenter; NDVI was the best predictor of CWD influx. We categorized the geospatial CWD predictions from the NDVI-derived model to map the spatial distribution of sun-exposed, moist-shaded, dry-shaded and wet CWD microhabitats on the forest floor. Moist-shaded, dry-shaded and wet patches of CWD were large and well connected, but sun-exposed patches were small and sparse. Since these microhabitats affect the distribution and abundance of saproxylic insects, wood-rotting fungi, salamanders, birds, small burrowing mammals and plant species dependent on nurse-logs for establishment, the CWD influx from the 1998 ice storm may have revitalized local populations of these taxa through increased habitat availability as well as increased dispersal within the reserve.  相似文献   

17.
Book reviewed     
《Journal of Phytopathology》1998,146(2-3):150-153
Book reviewed in this article:
Utrich Gisi und Mitabeiter: Bodenokologie, 2, neu bearbeitete und erweiterte Auflage
Ganzeimeier, H., D. Rautmann, IM. Streloke, M. Herrmann, H. J. Wenzeiburger, H. F. Walter: Studies on the Spray Drift of Plant Protection Products
Ream, W. and S, B. Gelvin (eds): Crown Gall: Advances in Understanding Interkingdom Gene Transfer.
Eylenbosch, E. J. K.: Elsevier's Dictionary' of Pests and Diseases in Useful Plants.
Lichtenthaler, H. K. (ed.): Vegetation Stress. Based on the International Symposium on Vegetation Stress, Munich-Neuherberg.
Grace, J. B, and D. Tibnan (Eds): Perspectives on Plant Competition  相似文献   

18.
A previous national survey of Escherichia coli in Norwegian sheep detected eae-positive (eae(+)) E. coli O26:H11 isolates in 16.3% (80/491) of the flocks. The purpose of the present study was to evaluate the human-pathogenic potential of these ovine isolates by comparing them with E. coli O26 isolates from humans infected in Norway. All human E. coli O26 isolates studied carried the eae gene and shared flagellar type H11. Two-thirds of the sheep flocks and 95.1% of the patients harbored isolates containing arcA allele type 2 and espK and were classified as enterohemorrhagic E. coli (EHEC) (stx positive) or EHEC-like (stx negative). These isolates were further divided into group A (EspK2 positive), associated with stx(2-EDL933) and stcE(O103), and group B (EspK1 positive), associated with stx(1a). Although the stx genes were more frequently present in isolates from patients (46.3%) than in those from sheep flocks (5%), more than half of the ovine isolates in the EHEC/EHEC-like group had multiple-locus variable number of tandem repeat analysis (MLVA) profiles that were identical to those seen in stx-positive human O26:H11 isolates. This indicates that EHEC-like ovine isolates may be able to acquire stx-carrying bacteriophages and thereby have the possibility to cause serious illness in humans. The remaining one-third of the sheep flocks and two of the patients had isolates fulfilling the criteria for atypical enteropathogenic E. coli (aEPEC): arcA allele type 1 and espK negative (group C). The majority of these ovine isolates showed MLVA profiles not previously seen in E. coli O26:H11 isolates from humans. However, according to their virulence gene profile, the aEPEC ovine isolates should be considered potentially pathogenic for humans. In conclusion, sheep are an important reservoir of human-pathogenic E. coli O26:H11 isolates in Norway.  相似文献   

19.
Abstract

Account on the Cartography of the Vegetation of the Basin of Bormio (Valtellina). Presentation of the phytosociological Map 1:5000. — The authors illustrate the features of the new phytosociological map of the basin of Bormio (Valtellina). The chief types of vegetation of the region are outlined.  相似文献   

20.
Background: In Southern Brazil, large areas of grassland have been replaced by Eucalyptus plantations. Vegetation is scarce under plantations which may be associated with Eucalyptus releasing of allelochemicals.

Aims: To investigate effects of Eucalyptus saligna leaf litter on the colonisation and development of the ground layer by grassland species and if these effects were related to allelopathy.

Methods: We assessed the effects of Eucalyptus litter on the establishment of species of the native grassland community and on seeded test species (Paspalum notatum and Lotus corniculatus – introduced). We tested the impact of the addition of E. saligna leaf litter, artificial leaves (shading and mechanical impediment) and shading. We also tested the phytotoxicity of the soil from E. saligna plantations.

Results: Species richness, diversity, plant height, cover and biomass were lower in E. saligna leaves and artificial leaves treatments than in the control (absence of litter). The test species showed lower biomass and higher mortality in treatment plots with E. saligna leaves, artificial leaves and shading treatments than in the control. Allelochemicals did not accumulate in soil at phytotoxic levels.

Conclusions: Eucalyptus saligna leaf litter suppresses the establishment of grassland vegetation, but the effects are mainly physical. Field evaluations with appropriate controls should be more extensively used in allelopathy investigations.  相似文献   


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