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1.
王献溥  李俊清 《植物研究》2000,20(3):332-350
拟赤杨林是亚热带落叶阔叶林的一个群落类型,属于常绿阔叶林演替系列的一个演替阶段,主要见于东部中亚热带地区海拔1300m以下的红壤和黄壤山地山坡中下部环境比较湿润的地方,本文研究划分出3个群丛纲和13个群丛。它向常绿阔叶林恢复的演替趋向,从13个群丛之间的群落外貌,结构和种类组成变化的分析可以得到充分的证明。  相似文献   

2.
广西细叶云南松群系的初步研究   总被引:2,自引:2,他引:0  
王献溥 《植物研究》1987,7(1):127-150
细叶云南松是云南松原种从中亚热带温凉的云南高原向东迁移,适应南亚热带于热河谷的一个变种。它广泛分布在南盘江下游两岸海拔300-1600米的丘陵山地,常常构成大面积的天然森林,群落类型多种多样。它们的形成和分布与所在地的气候、地貌、土壤和人为生产活动特别是垦殖和烧山的影响有密切的联系。本文比较详尽地划分和论述了这个区域广西范围内细叶云南松群系各个群丛的基本特点和分布规律,指出了它们的演替趋势和经营管理应采取的主要措施。  相似文献   

3.
广西光皮桦林的分类和演替   总被引:10,自引:1,他引:9  
王献溥  孙世洲  李信贤   《广西植物》1998,18(2):123-138
光皮桦林是常绿阔叶林或山地常绿落叶阔叶混交林遭受砍伐后,在保护较好的情况下自然恢复起来的一种演替系列群落,属亚热带落叶阔叶林的一种类型。本文通过群落分类研究,划分出3个群丛纲和11个群丛。从这些群丛的外貌、结构和种类成分的变化,可确定其演替的趋向和所处阶段,是合理经营管理它的科学依据。  相似文献   

4.
广西落叶栎林的分类研究   总被引:4,自引:0,他引:4  
王献溥  李俊清   《广西植物》1999,19(4):323-333
广西的落叶栎林属亚热带落叶阔叶林的一个群系组, 常见有栓皮栎林、麻栎林和白栎林3 个群系。主要论述其类型划分和生境特点, 为其经营管理和合理利用提供基本材料和依据。  相似文献   

5.
Summary Carbonate-dominated successions of the Gipsdalen and Tempelfjorden Groups from Svalbard record a significant shift from Photozoan to Heterozoan particle associations in neritic settings during the late Palaeozoic. During the Bashkirian, benthic particle associations which included photoautotrophs such as phylloid algae (Chloroforam Association) characterised shallow subtidal environments. Most depositional settings which endured siliciclastic terrestrial input exhibited poorly diversified associations dominated by brachiopods, bryozoans and siliceous sponges (Bryonoderm Association). During the Moscovian to Asselian, highly diversified associations typified by various calcareous green algae,Palaeoaplysina, Tubiphytes, fusulinids, smaller and encrusting foraminifers (Chloroforam Association) prevailed in carbonate sediments from supratidal to shallow subtidal environments. During the Sakmarian and Early Artinskian, oolitic carbonate sands (Chloroforam Association) typified intertidal flats, whereas shallow subtidal environments were occupied by moderately diversified associations with fusulinids, smaller foraminifers, echinoderms and bryozoans (Bryonoderm-extended Association) and poorly diversified associations with echinoderms, brachiopods and bryozoans (Bryonoderm Association). During the Late Artinskian to Kazanian, poorly diversified associations characterised by brachiopods, echinoderms and bryozoans (Bryonoderm Association), and sponge-dominated associations (Hyalosponge Association) reigned within siliceous carbonates of intertidal and shallow subtidal environments. This trend is interpreted as a result of climatic cooling and fluctuations of prevailing levels of trophic resources within shallow-water settings during the studied time period. While raised nutrient levels were restricted to near-shore settings during the Bashkirian, steady mesotrophic conditions arose from the Sakmarian onward and increased to late Permian times.  相似文献   

6.
《BMJ (Clinical research ed.)》1968,3(5616):485-492
The One Hundred and Thirty-sixth Annual Meeting of the British Medical Association was held in Sydney from 10 to 16 August jointly with the Seventh Annual Meeting of the Australian Medical Association. Both meetings were associated with the Third Australian Medical Congress. It was the second Annual Meeting of the Association to be held in Australia, the previous one having been in Melbourne in 1935. Four plenary sessions were held on successive mornings, while meetings of various sections were held in the afternoons. An account of the first part of the Meeting is given below. The remainder will be reported next week.  相似文献   

7.
Abstract

The following article was awarded the second-place Reston Prize 1989, sponsored by the National Association of Schools of Art and Design, the National Association of Schools of Dance, the National Association of Schools of Music, and the National Association of Schools of Theatre.  相似文献   

8.
Quilts     
Abstract

The following article was awarded the third-place Reston Prize 1989, sponsored by the National Association of Schools of Art and Design, the National Association of Schools of Dance, the National Association of Schools of Music, and the National Association of Schools of Theatre.  相似文献   

9.
《CMAJ》1995,153(11):1652A-1652F
This joint statement includes: guiding principles for health care facilities when developing cardiopulmonary-resuscitation (CPR) policy; CPR as a treatment option; competence; the treatment decision, its communication, implementation and review; and palliative care and other treatment. This joint statement was approved by the Canadian Healthcare Association, the CMA, the Canadian Nurses Association and the Catholic Health Association of Canada and was developed in cooperation with the Canadian Bar Association.  相似文献   

10.
广西大穗鹅耳枥林的分类和演替趋向   总被引:4,自引:1,他引:4  
大穗鹅耳枥林是广西东北部黄壤山地常绿阔叶林遭受砍伐后,在保护较好的情况下迅速发展起来的一个演替阶段。本文通过群落分类的研究,从不同群丛的外貌、结构和种类组成的变化,论证其向常绿阔叶林恢复过程的演替趋向。  相似文献   

11.
The Council of the Association of Applied Biologists is concerned about the standards of presentation and illustration of some papers at meetings of the Association. The following notes have therefore been drawn up to emphasize those points which are considered to require special attention and to assist speakers to present their talks effectively.
These notes may be copied in whole or in part without further permission.  相似文献   

12.
The CHARGE Association is a nonrandom occurrence of congenital malformations that has been described in clinical series. Reported patients have been selected on the basis of certain prior criteria. In this article, we try to identify a congenital malformation pattern corresponding to the CHARGE Association, using statistical methods and analyzing 5,260 infants with multiple malformations collected from four large registries of congenital malformations. Care was taken to identify a number of confounding characteristics that can influence the ascertainment and registration of specific congenital malformations. We have identified a cluster of malformations that generally agreed with the current clinical definition of the CHARGE Association and have added some further malformations (e.g., facial clefts). We demonstrate that others (e.g. , esophageal atresia) are probably not part of the pattern. Heart defects (H in the acronym) seems to be less helpful in identifying infants with the association. We suggest a method to select infants who probably represent the CHARGE Association for analyses of possible risk factors.  相似文献   

13.
根据对新疆博格达山地面生地衣群落27个样点(20 m×20 m)调查的数据,以各地衣种的盖度为指标结合双向指示种分析方法(TWINSPAN)和除趋势对应分析法(DCA)对博格达山地面生地衣群落进行数量分类并分析了群落结构特征及其多样性和相似性。采用典范对应分析法(CCA)对各群落的物种分布格局与环境因子的关系进行了探讨。结果表明,TWINSPAN分析和DCA排序将分布在博格达山的37种地面生地衣分为以下5个群丛。群丛1:膜地卷(Peltigera membranacea)+伴藓大孢蜈蚣衣(Physconia muscigena)群丛;群丛2:地卷(Peltigera rufescens)+伴藓大孢蜈蚣衣(Physconia muscigena)群丛;群丛3:裂边地卷(Peltigera degenii)+平盘软地卷(Peltigera elisabethae)群丛;群丛4:喇叭石蕊(Cladonia pyxidata)+犬地卷(Peltigera canina)群丛;群丛5:盾鳞衣(Placidium squamulosum)+缠结茸枝衣(Seirophora contortuplic...  相似文献   

14.
Peat,horticulture and environment   总被引:2,自引:0,他引:2  
Peat-based growing media underpin the horticultural industry in the UK, although production sites cover less than 0.5% of the total peatland area. In recent years Peat Producer's Association members have released over 20% of their holdings to English Nature, representing virtually all the areas of current conservation value. The Association is now engaged in the assessment and development of restoration measures.  相似文献   

15.
This article was prepared by Mr. William M. Whelan, Director of Special Services, California Medical Association, under the supervision of Dr. Francis J. Cox, Chairman of the Medical Services Commission of the Association, and Mr. Howard Hassard, the Association's Legal Counsel. It is intended as a brief synopsis of the California Workmen's Compensation Law as it applies to the physician in private practice. It is not an exhaustive treatment of the subject. A physician who desires to acquaint himself in detail with California industrial practice should consult the article entitled "The Physician's Role in Workmen's Compensation," California Medicine, 82:352-362, April, 1955. Inquiries regarding industrial medicine should be addressed to Mr. William M. Whelan, California Medical Association, 450 Sutter St., San Francisco 8.  相似文献   

16.
The American Association of Tissue Banks (AATB) is a scientific, not-for-profit, peer-group organization founded in 1976 to facilitate the provision of transplantable tissues of uniform high quality in quantities sufficient to meet national needs. The Association was created well before there was governmental oversight of tissue banking. The organization consists of individuals involved in tissue banking, medical users, and scientists in the field. Current structure consists of a 13-member Board of Governors with specific subgroups including Musculoskeletal, Reproductive, Skin, Tissue Bank Councils and Council of Accredited Tissue Banks. A historical review shows the evolution from development of guidelines to publication of standards, and from an inspection conducted by peers to one conducted by an independent, trained professional inspector. Association growth and historical accomplishments are highlighted.  相似文献   

17.
湖北宜昌大坪奥陶纪阿仑尼克期三叶虫生态组合   总被引:6,自引:2,他引:4  
首次对扬子区奥陶纪大湾组的三叶虫相作了初步分析。在详细研究了湖北宜昌大坪大湾组30种三叶虫的地层和岩相分布的基础上,划分出3个生态组合,即:Asaphid-Pseudocalymene组合,Asaphid-Raphiophorid组合和Trinucleid组合,它们依次指示由浅而深的浅外陆棚环境。研究表明这3个组合在大湾组的交替出现应与阿仑尼克期海平面变化密切相关。  相似文献   

18.
毕培曦   《广西植物》1988,(1):65-74
毕培曦博士在本文中提出我国植物标本室代号的统一问题很值得注意,应该求得解决,达到国内、外使用统一代号,以利中外学术交流,促进本学科发展。至于如何解决,希望同行们提出宝贵意见,写给本刊编辑部,以便刊出,公开讨论。  相似文献   

19.
《Palaeoworld》2022,31(2):258-276
Late Devonian–Early Carboniferous spores recovered from the depths of 2140 m to 2031.3 m in the CSDP-2 Borehole in the southern Yellow Sea are systematically documented to characterize palynological associations for the stratigraphic correlation. The taxonomic study identifies 96 species belonging to 48 genera, including a re-examination of 33 previously described and indeterminate species. Three palynological associations are established for the Wutong Formation in the CSDP-2 Borehole. In ascending order, these are the late Famennian Aneurospora asthenolabrataGeminospora lemurata (AL) Association from the proposed Guanshan Member, the latest Famennian Cymbosporites circinatusAsperispora acuta (CA) Association from the lower part of the proposed Leigutai Member, and the Tournaisian Auroraspora macraLophozonotriletes involutus (MI) Association of the upper part of the latter member. The AL and CA associations are correlated with the palynological assemblages in the Guanshan Member, and those in the lower to middle parts of the Leigutai Member of the Wutong Formation that outcrops in the suburbs of Nanjing and southern Jiangsu. The MI Association is similar to those derived from the uppermost beds of the subsurface Wutong Formation and is dated as early Tournaisian.  相似文献   

20.
The following remarks are excerpts from an address by T. Eric Reynolds, M.D., President of the California Medical Association, at a meeting of the Woman's Auxiliary to the California Medical Association, Santa Barbara, September, 1959.  相似文献   

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