1,720,977 research outputs found
Effect of Compost Combination on Methane Emission in Undisturbed Acid Sulphate soil in South Kalimantan of Indonesia
Get PDFA greenhouse experiment was conducted to examine the cumulative methane (CH4) emission in paddy soils and correlation with soil redox potential (Eh), soil pH and plant growth. The experiment was arranged in two factorial randomized block designs with three replications. The first factor was a kind of of organic matter, i.e. without organic matter (T0), combination of 50% of composted straws and 50% composted rush weed (T1), combination of 30% of composted straws and 30% composted rush weed and 40% composted cattle manure (T2) and the second factor was the management of water that was continuously flooded and leaching. The methane emission was measured in South Kalimantan using the chamber and gas chromatogram technique. The results showed methane emission in undisturbed acid sulphate soil ranged from 0.05 to 0.32 mg CH4.m-2.minute-1 during the rice-growing season. The methane emission from the paddy soil were lower when the paddy was drained than when it was flooded. Correlation analysis showed a negative relation between methane emission and soil redox potential (Eh) and soil pH in both water management. The rice plant height and number of buds has positively correlation with methane emission with coeffecient correlation of r=0.84**(P<0.0001) and r=0.64**(P=0.004), respectively. [How to Cite: Wahida A and A Maas. 2015. Effect of Compost Combination on Methane Emission in Undisturbed Acid Sulphate soil in South Kalimantan of Indonesia. J Trop Soils 20: 135-141. Doi: 10.5400/jts.2015.20.3.135]
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Soil and climate information for agribusiness development A case study on southern part of Yogyakarta Special Territory.
Get PDFKata kunci: Soil and Climate Information - Agribusiness
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
AMELIORASI TANAH SULFAT MASAM POTENSIAL UNTUK BUDIDAYA TANAMAN PANGAN YANG DIKELOLA DENGAN SISTEM MEKANISASI
No full textTanah sulfat masam potensial tersebar di daerah rawa yang masuk dalam eks wilayah Pengembangan Lahan Gambut 1 juta hektar (eks PPLG). Proses reklamasi lahan rawa seperti ini sebelumnya digunakan untuk padi sawah dengan cara pengusikan minimum yang memungkinkan proses oksidasi berjalan lambat dan hasil oksidasi yang berupa asam sulfat dapat segera terencerkan oleh air genangan dan terlindi ke luar dari lingkungan perakaran. Mengingat pola saluran yang direncanakan satu arah dan tidak secara langsung dipengaruhi oleh pasang surut, dan watak air yang berbeda antara musim kemarau dan musim hujan serta kemampuan petani yang terbatas untuk mengolah tanah, maka proses pengolahan tanah dengan sistem mekanisasi merupakan tantangan yang cukup serius mengingat produksi asam sulfat akibat usikan dan aerasi akan dipacu sehingga dapat berada di atas ambang toleransi tanaman. Untuk itu perlu dipelajari hubungan antara potensi kemasaman dengan laju pengeluaran asam sepanjang masa pertanaman, baik di musim kemarau maupun di musim hujan yang di kedua musim tersebut tanahnya diolah secara mekanis dengan traktor. Dengan diketahuinya laju oksidasi dan perilaku air yang ada, maka dapat diantisipasi berapa besaran takaran bahan penetral kemasaman (amelioran) dan interval pemberiannya yang memungkinkan produksi tanaman tidak terganggu akibat keracunan asam sulfat tersebut. Tujuan khusus penelitian tahun kelima ini adalah: a. Melihat pengaruh pengolahan tanah secara mekanisasi terhadap evolusi keamasaman tanah terlaru&an dan kejenuhan aluminium pada akhir pengolahan di tanah sulfat masam reaktif dan tidak reaktif, b. Mempercepat laju oksidasi pirit dengan mengintensifkan proses pembasahan pengeringan pembilasan berkesinambungan (olah intensif) dan memanfaatkan air laut, c. Mencari alternatif kombinasi kapur dan pupuk organik yang mampu berperan sebagai penetral dan pengisi nutrisi pada tanah sulfat masam yang reaktifitasnya telah diredakan dan diperlakukan dengan air laut. Rancangan percobaan disusun secara acak lengkap dengan parameter: I. Parameter (1) berupa 2 jenis tanah sulfat masam: (a) tanah reaktifitas tinggi, belarosit dan (b) tanah dengan reaktifitas rendah, tanpa jarosit, II. Parameter (2) berupa pemakaian air laut sebagai amelioran penukar: (a) dibilas dengan air laut 50%, dan (b) dibilas dengan air suling, III. Parameter (3) imbangan kombinasi bahan amelioran (a) pupuk kandang kapur dan (b) pupuk kandang semen (Porland cement), masing masing dengan takaran pupuk kandang 2,5 ton/ha (al dan bl) dan 5,0 ton/ha (a2 dan b2). Kebutuhan kapur/semen sesuai dengan penurunan aluminium menjadi 350 tahun, c. Air laut dapat berfungsi sebagai amelioran dengan jalan menukarkan sumber kemasaman dalam kompleks pertukaran dengan kation basa (Ca dan Mg serta K) yang ada dalam air laut tersebut. Diperlukan waktu yang lebih lama (> 7 minggu) untuk membilaskan sisa air laut untuk menghindari plasmolisis akar tanaman, dan d. Penyelesaian penelitian masih memerlukan waktu yang disesuaikan dengan kesudahan penurunan nilai DHL untuk percobaan pot
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