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Species Diversity and Characteristic of Mangrove Forest at Bang Pakong Power Plant, Chachoengsao Province
Full text linkRiverine forests are unique ecosystems that distribute among urban areas induced the forest patches. Then, the conservation of mangrove ecosystems requires the sufficient data and information about the characteristics of mangrove plants. This research aimed to clarify the species composition and structure of mangrove communities at Plant Genetic Protection Area of RSPG - Bangpakong powerplant. The four sample plots (A, B, C, D) of 10 x 50 m were set up across the coast of Bang Nang canal directed into the remnant of mangrove forest. The results showed that true mangroves species was found, 15 species 13 genera 10 families and the others were 3 species 3 genera 2 families. The total density and basal area were 790 individual.ha-1 and 7.15 m2.ha-1, respectively. Based on importance value index, Xylocarpus granatum J. Koenig, Excoecaria agallocha L. Thespesia populniodes (Roxb.) Kostel. were dominance species in site A, B-C and D respectively. The similarity index between the plots was intermediate value, 66.67 %. The low diversity indicated that. The diversity index (H/) of each plot was very low (ranged from 0.95 - 1.15), thus, the forest restoration should been done for increasing high species diversity. In order to increase the natural establishment of seedlings and saplings, mangrove forest area protection is urgently needed
กายวิภาคศาสตร์เปรียบเทียบและสัณฐานวิทยาเรณูของผักตบไทย (Monochoria hastata (L.) Solms var. hastata) และผักตบชวา (Eichhornia crassipes (Mart.) Solms)
Full text linkComparative Anatomy and Pollen Morphology of Pondweed (Monochoria hastata (L.) Solms var. hastata) and Water Hyacinth (Eichhornia crassipes (Mart.) Solms)
Benchawon Chiwapreecha and Supakorn Thaima
รับบทความ: 15 พฤศจิกายน 2561; แก้ไขบทความ: 27 กรกฎาคม 2562; ยอมรับตีพิมพ์: 15 กันยายน 2562
บทคัดย่อ
การศึกษากายวิภาคศาสตร์เปรียบเทียบและเรณูวิทยาของผักตบไทย (Monochoria hastata (L.) Solms var. hastata) และผักตบชวา (Eichhornia crassipes (Mart.) Solms) ซึ่งเป็นพืชน้ำในวงศ์ Pontederiaceae ที่พบในแหล่งที่อยู่อาศัยเดียวกัน ศึกษาลักษณะทางกายวิภาคศาสตร์ของแผ่นใบ ก้านใบ และก้านช่อดอก ด้วยกรรมวิธีพาราฟิน (paraffin method) ลอกผิวแผ่นใบเพื่อศึกษาเนื้อเยื่อชั้นผิว พบลักษณะที่มีความแตกต่างกัน ได้แก่ ภาคตัดขวางของแผ่นใบ ก้านใบ และก้านช่อดอกของผักตบไทย มีปริมาณคลอเรงคิมาร้อยละ 35.65±5.74 6.78±0.28 และ 6.34±0.19 ต่อตารางมิลลิเมตร ตามลำดับ ซึ่งมากกว่าของผักตบชวา (ร้อยละ 23.95±0.44 3.82±0.37 และ 1.00±0.28 ต่อตารางมิลลิเมตร ตามลำดับ) ในทำนองเดียวกัน ชั้นแพลิเซดในแผ่นใบของผักตบไทยมีความหนา 6–8 ชั้นเซลล์ ซึ่งมีจำนวนชั้นมากกว่าผักตบชวาที่มีเพียง 4–6 ชั้นเซลล์ ความหนาแน่นปากใบของผักตบไทยเท่ากับ 129.33±5.98 ปากใบต่อตารางมิลลิเมตร ซึ่งมากกว่าผักตบชวาที่มี 115.07±2.52 ปากใบต่อตารางมิลลิเมตร ในขณะที่แอเรงคิมาในแผ่นใบของผักตบไทยมีความหนาเพียง 1 ชั้นเซลล์ แต่ผักตบชวาหนา 1–3 ชั้นเซลล์ นอกจากนี้ยังพบตำแหน่งปากใบที่ระดับเดียวกับเนื้อเยื่อชั้นผิว (typical stomata) และสูงกว่าเนื้อเยื่อชั้นผิว (raised stomata) รวมถึงการสะสมผลึก ในทุกส่วนที่ทำการศึกษาของผักตบไทย ในขณะที่ก้านใบและก้านช่อดอกของผักตบชวาพบเฉพาะปากใบที่ระดับเดียวกับเนื้อเยื่อชั้นผิว และพบการสะสมผลึก การศึกษาลักษณะทางสัณฐานวิทยาของเรณู ด้วยกรรมวิธีอะซีโตไลซิส (acetolysis) แสดงลักษณะเด่นร่วมกันของพืชทั้ง 2 ชนิด ได้แก่ เป็นเรณูเดี่ยว (monad) สมมาตรแบบด้านข้าง (bilateral) ขั้วแบบ heteropolar ช่องเปิดแบบ monosulcate และ รูปร่างแบบ oblate สำหรับลักษณะที่แตกต่างกัน พบว่า ผักตบไทยมีเรณูขนาดกลางถึงใหญ่ (33–56 ไมครอน) และลวดลายบนผนังเป็นแบบ granulate ในขณะที่ผักตบชวามีเรณูขนาดใหญ่ (59–84 ไมครอน) และลวดลายบนผนังเป็นแบบ rugulate
คำสำคัญ: ชนิดพันธุ์ต่างถิ่น พืชน้ำ เรณูวิทยา เนื้อเยื่อพืช
Abstract
The comparative anatomy and pollen morphology of pondweed (Monochoria hastata (L.) Solms var. hastata) and water hyacinth (Eichhornia crassipes (Mart.) Solms) that found in the same habitat were studied. For anatomy, paraffin method was examined of the transverse section on leaf blade, petiole and peduncle. The leaf blade surfaces were peeled to study the epidermal layers. The result showed there was difference in quantity of chlorenchyma in leaf blade, petiole and peduncle between M. hastata and E. crassipes: M. hastata were higher than E. crassipes (35.65±5.74, 6.78±0.28 and 6.34±0.1 %/mm2 respectively vs 23.95±0.44, 3.82±0.37 and 1.00±0.28 %/mm2 respectively). Also, there were higher number of palisade mesophyll layers on M. hastata (6–8 layers) than on the E. crassipes (4–6 layers), and there were higher of stomata density on M. hastata (129.33±5.98 stomata/mm2) than on E. crassipes (115.07± 2.52 stomata/mm2). However, M. hastata showed equal or lower in the number of aerenchyma layers in mesophyll (1 layer) than on E. crassipes (1–3 layers). In addition, the above three parts (leaf blade, petiole and peduncle) of M. hastata and the leaf blade of E. crassipes showed typical and raised stomata, and the crystal accumulation, while the petiole and peduncle of E. crassipes were only showed the typical stomata and there was crystal accumulation. Later, acetolysis method was used to study pollen morphology. It was found that both species’ pollen was monad, bilateral symmetry, heteropolar, monosulcate and oblate shape. However, there was difference in pollen size and exine sculpturing between these two species. M. hastata was medium to large (33–56 µm) and granulate, while E. crassipes was large (59–84 µm) and rugulate.
Keywords: Alien species, Aquatic plant, Palynology, Plant tissu
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Species diversity of ferns in agricultural and urban areas of Khlung district, Chanthaburi province
Full text linkSpecies diversity of ferns in Khlung district, Chanthaburi province was explored and collected specimen from December, 2015 to January, 2019. Forty species, 28 genera and 19 families can be identified. The 7 species of Polypodiaceae were found the most in the study sites. The habits can be divided into 4 types consisting of 22 terrestrial ferns, 12 species of epiphytic fern, 5 species of climbing fern and 1 species of aquatic fern. Angiopteris evecta (Forst.) Hoffm, Cibotium barometz (L.) J.Sm. and Platycerium coronarium (Mull.) Desv. were uncommon found in this local habitat. The highest number of species was found at Bo Walu sub-district while the lowest was found at Kwian Hak sub-district. Thus, the result can be used to planning for conservation of ferns resource in situ conservation
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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