首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 7 毫秒
1.
Bryophytes are a rewarding study group in field biology and the UK bryophyte flora has international importance to biodiversity conservation. We designed an identification key to common woodland moss species and compared the usability of two formats, web-based multi-access and printed dichotomous key, with undergraduate students. The rate of correct species identification and identification speed both showed an advantage for the printed dichotomous key. Our findings suggest that, even in the digital age, printed keys remain valuable in biological education and that quality of key design is more important than presentation medium. We discuss the relative advantages of multi-access and dichotomous keys and how to approach bryophyte identification with beginners.  相似文献   

2.
Four homograms are presented which enable the field worker to identify 168 genera of rainforest trees in Papua New Guinea. These keys are based on simple field characters such as sap colour and leaf features. To assist identification, illustrations are given of the most important field characters. With modifications similar keys could be developed for most rainforest situations. This method of key construction could be widely applied in both botanical and zoological fields.  相似文献   

3.
A set of biochemical keys which provide fast and presumptive identification for Vibrio spp. is presented. They have been specially designed for environmental isolates, and can be used for strains that are Gram-negative, give a positive oxidase test, grow on TCBS medium and are facultative anaerobes. The keys are constituted by 28 tests and a maximum of 10 tests are needed for the most complicated identification. They have been designed for routine purposes, especially for studies with a high number of isolates. Some tests are included in enzyme-activity based kits that could be used with these keys through certain results, principally for environmental isolates, should be confirmed by standard methods.  相似文献   

4.
有关《植物园学》问题的讨论   总被引:9,自引:0,他引:9  
林有润  谢振华 《植物研究》2004,24(3):379-384
讨论了世界及我国植物园的建立、发展及近代植物园的性质与任务.本文第一作者曾指出中国科学院下属植物园的建立、建设和以科研为先导,推动科普与生产等工作,可以概括为一新兴的、综合性的学科--植物系统与工程学,或称新植物园学.并对中国科学院下属植物园科研、科普、建园、生产等作过论述.另外指出中国植物园与发达国家植物园之间的差距在于中国植物园的体制、管理机制、经济支撑与高素质的科技人才的努力工作精神.同时中国植物园信息研究、管理与交流滞后;在园貌建设方面,中国植物园与发达国家植物园相比,缺乏中国经典的建筑群与雕塑群,也缺少具中国特色的"师出自然"的造园手法与造林中的"适地适树"的有机结合等.过去提出植物园主要任务是植物引种驯化,即"从种子到种子".作者认为过分强调"从种子到种子"有其"误区".对园艺花卉、蔬菜及观叶植物而言,只需能长好叶或开好花,能批量生产、快速繁殖出来满足市场需要就是成果,而无需考虑种子的出处,或种子的有或无.原产中国多种杨树及柳树种子生育力已极度退化,原产地都难以"从种子到种子",但却是速生、无性繁殖力极强的树种.而若干有害杂草,如紫茎泽兰、薇苷菊、凤眼莲等从国外传入中国,无须"驯化"、却极容易"从种子到种子"的快速地繁衍,造成大面积的灾害.最后,作者强调发挥植物园作为植物大世界网上星罗棋布的一个闪亮发光的亮点的作用,加强信息研究、交流与传导工作,尤其在当今"知识创新工程"和新的"绿色革命"的浪潮的推动下,代表21世纪的新的技术革命的"纳米技术"与生物学的结合以及作为信息时代的信息研究与流通更显得必要.  相似文献   

5.
6.
《Small Ruminant Research》2008,78(2-3):221-224
This article describes Heifer International's experience promoting goats for the poor. Heifer International provides livestock to the poor in 55 countries using a value-based participatory approach. Drawing from recent case studies conducted in China, Peru, Romania and Tanzania, the benefits to the poor and major constraints are outlined. Constraints to livestock raising include the lack of good breeding stock, lack of veterinary and extension services, lack of credit and access to markets. Focusing more assistance on women farmers would improve impact on the poor. Value-based holistic community development with self-help groups creates a foundation for increasing farmer incomes by providing a forum for education, mutual support and developing markets.  相似文献   

7.
M. ALSINA AND A.R. BLANCH. 1994. Two biochemical keys for fast and presumptive identification of certain Vibrio species are presented. They constitute a new improved version of a set of keys previously described, which were specially designed for environmental and clinical isolates. They may be used for Gram-negative, oxidase-positive, facultative anaerobes that grow on TCBS agar. The revised set of biochemical keys consists of 29 tests and a maximum of 10 tests is still sufficient for the most complicated identification. The new keys maintain the same criteria and characteristics of the original set of keys.  相似文献   

8.
9.
The native distributions of Salvinia biloba Raddi and S. molesta D.S. Mitchell were localised, respectively, in areas north and south of the tropic of Capricorn on the east coast of Brazil. Salvinia herzogii de la Sota occurred in Uruguay, Paraguay, southern Brazil and northern Argentina, and S. auriculata Aublet from Trinidad to northern Argentina. Keys are given for identifying these species, which collectively are known as the S. auriculata complex, using the arrangement of sporocarps when the fertile axis is present and the pattern of leaf areolation when the fertile axis is absent.  相似文献   

10.
11.
A revision is made of the previously poorly studied blackfly fauna from the south-western border of Guyana with Brazil. Notes on the biosystematics of the species found are provided, together with keys and illustrations based on their morphology. Of the 14 species recorded, eight are anthropophilic and two of these (Simulium oyapockense s.l. and S. guianense s.l.) are proven vectors of human onchocerciasis in the nearby Amazonia focus of the disease in neighbouring Brazil.  相似文献   

12.
13.
Accurate species identification is fundamental to biodiversity science, but the natural history skills required for this are neglected in formal education at all levels. In this paper we describe how the web application ispotnature.org and its sister site ispot.org.za (collectively, “iSpot”) are helping to solve this problem by combining learning technology with crowdsourcing to connect beginners with experts. Over 94% of observations submitted to iSpot receive a determination. External checking of a sample of 3,287 iSpot records verified > 92% of them. To mid 2014, iSpot crowdsourced the identification of 30,000 taxa (>80% at species level) in > 390,000 observations with a global community numbering > 42,000 registered participants. More than half the observations on ispotnature.org were named within an hour of submission. iSpot uses a unique, 9-dimensional reputation system to motivate and reward participants and to verify determinations. Taxon-specific reputation points are earned when a participant proposes an identification that achieves agreement from other participants, weighted by the agreers’ own reputation scores for the taxon. This system is able to discriminate effectively between competing determinations when two or more are proposed for the same observation. In 57% of such cases the reputation system improved the accuracy of the determination, while in the remainder it either improved precision (e.g. by adding a species name to a genus) or revealed false precision, for example where a determination to species level was not supported by the available evidence. We propose that the success of iSpot arises from the structure of its social network that efficiently connects beginners and experts, overcoming the social as well as geographic barriers that normally separate the two.  相似文献   

14.
Four new species of longhorn beetles are described from Brazil: Coleoxestia diamantina n. sp. (Cerambycinae, Cerambycini), from Bahia; Mirador bravoi n. sp. (Cerambycinae, Ectenessini), from Bahia; Compsibidion antonietae n. sp. (Cerambycinae, Neoibidionini), from Goiás, Bahia and São Paulo; and Amphicnaeia quadrifasciata n. sp. (Lamiinae, Apomecynini) from Bahia. Coleoxestia diamantina and Compsibidion antonietae are included in previous keys.  相似文献   

15.
16.
Caves are oligotrophic, dark and less-explored environments and are considered as sources of promising microbial strains in biotechnology. Hampoeil Cave is located in massive dolomite with thin bedded limestone in northwestern of Iran. In an isolation and screening program, various samples from soil, water, floor, wall and ceiling of Hampoeil cave and its invertebrates were collected. Four various treatments and 10 different isolation media were used for the isolation of the actinobacteria. Screening of the isolates for antimicrobial activity against 10 bacteria and fungi, 5 hydrolytic enzymes production and resistance to 5 heavy metals have been performed. Among 33 various samples, 76 actinobacteria from various genera, including Streptomyces, Micromonospora, Micrococcus, Kocuria and Corynebacterium were isolated. Eighty percent of the strains had one of the studied hydrolytic enzyme activity. At least one type of antimicrobial activity was seen in 25.3% of the isolates. Resistance to one metal or more was seen in 26.32% of the isolates. The ratio of rare-actinobacteria in the oligotrophic samples to enriched samples is 20% more than Streptomyces. Percentage of strains with the highest activity in esterase, amylase, DNase, protease or lipase activity that were isolated from organic-rich environmental samples were 100, 100, 100, 82 and 82%, respectively. Also, 26.32% of the actinobacterial isolates resisted to heavy metals. It was concluded that Hampoeil cave is a good source in finding cave-living actinobacteria potent in producing hydrolytic enzymes and bioremediation.  相似文献   

17.
Benzimidazole‐derived ICT‐based probe, DFPBEN is developed for trace level determination of water. In presence of water, the naked eye color of DFPBEN changes from red to yellow, while it turns to green from red under UV light. Upon addition of water, DFPBEN shows a ratiometric absorbance change in methanol. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

18.
A pilot-scale submerged membrane bioreactor was used for the treatment of domestic wastewater in order to study the influence of the variations in the concentration of volatile suspended solids (VSS) on the enzymatic activities (acid and alkaline phosphatases, glucosidase, protease, esterase, and dehydrogenase) and biodiversity of the bacterial community in the sludge. The influence of VSS concentration was evaluated in two separated experiments, which were carried out in two different seasons of the year (experiment 1 through spring–summer and experiment 2 through autumn–winter). Cluster analysis of the temperature gradient gel electrophoresis (TGGE) profiles demonstrated that the community composition was significantly different in both experiments. Within the same experiment, the bacterial community experienced sequential shifts as the biomass accumulated, as shown by the evolution of the population profiles through time as VSS concentration increased. All enzymatic activities studied were significantly lower during experiment 2, except for glucosidase. Concentrations of VSS over 8 g/l induced a strong descent of all enzymatic activities, which overlapped with a significant modification of the community composition. Sequences of the major TGGE bands were identified as representatives of the Alpha-proteobacteria, filamentous bacteria (Thiotrix), and nitrite oxidizers (Nitrospira). Some sequences which were poorly related to any validated bacterial taxon were obtained.  相似文献   

19.
20.
A conceptual model of the possible role of lipids in the lifecycle of Calanus finmarchicus is proposed. Lipid storage couldplay a key role at various levels: (i) by triggering diapausethrough variations in cholesterol and fatty acid derived hormonelevels; (ii) by determining the overwintering depth in relationto the convective mixed layer; and (iii) by playing an importantrole in the population adaptation to the hydrological conditionsof the basin. A number of ways to test the validity of the proposedhypotheses are proposed. Written responses to this article should be submitted to theEditorial Office within two months of publication. For furtherinformation, please see the Editorial ‘Horizons’in Journal of Plankton Research, Volume 26, Number 3, Page 257.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号