1,720,987 research outputs found
(37(1):47-57)The Effects of Long-term Pineapple Stubble Mulching on Slopeland Pineapple Orchard
No full text坡地鳳梨園以鳳梨殘株敷蓋為經濟有效的水土保持方法。為明瞭長期鳳梨殘株之水土保持效益，本試驗以不同鳳梨殘株敷蓋方式及不同施肥量對土壤流失，土壤理化性質及鳳梨生育和產量之影響進行長期研究。試驗資料顯示：各處理對土壤流失控制及保持土壤水分效果，依次為殘株敷蓋施全量、2/3量及1/2量肥料區，均較對照區（未敷蓋施全量肥料）為佳，各處理間差異顯著。第二更新期鳳梨園土壤理化性測定結果除殘株垂直敷蓋施全量肥料處理區外，較第一更新期皆有劣化現象。土壤有機質、有效性磷及交換性鉀含量測定結果，各處理間差異均達顯著標準，皆以殘株垂直敷蓋施全量、2/3量肥料區較佳。土壤假比重、孔隙率導水率在試驗初期皆以翻犁區為佳，各處理間差異顯著，至試驗後期則各處理間差異不顯著。土壤分散率、團粒穩定性、保水特性等測定結果，殘株敷蓋施全量、2/3量及1/2量肥料區均較對照區為佳。第二更新期鳳梨產量除殘株垂直敷蓋施全量肥料區外，較第一更新期皆有減產現象。各處理間差異顯著，以殘株垂直敷蓋施全量及2/3量肥料區較高。二個更新期鳳梨殘株收量除殘株垂直敷蓋施全量肥料區外，均有下降現象，以第二更新期降低較多，敷蓋量直接影響水土流失、土壤水分含量、土壤理化性及鳳梨生育和產量，實施鳳梨殘株垂直敷蓋施全量肥料可維持殘株產量。綜上所述長期殘株敷蓋以垂直方式施全量肥料對土壤流失的控制，土壤水分的保持，土壤物理性的改善及地力的維持或增進最佳，可促進鳳梨生育和提高其產量。其他殘株處理及對照區皆不可行。據試驗結果在近似本試區條件之坡地鳳梨園第一更新期利用鳳梨殘株敷蓋可節省1/3肥料用量，而第二更新期後，雖利用殘株敷蓋但減施肥料用量皆有減產現象。連續栽植鳳梨欲維持或增進其產量，需採用鳳梨殘株垂直敷蓋施全量肥料處理。
Using pineapple stubble stubble mulching on slopeland for pineapple orchard is the effective and economical method for soil conservation. In order to understand the long-term effectiveness, different methods of pineapple stubble mulching and different amount of fertilizer application were used in this experiment for studing their influences on soil loss, soil physico-chemical changes, pineapple growing and yielding. The results showed that all the pineapple stubble mulching treatments had better results to control soil erosion and to maintain soil moisture content than the clean cultivation and their effectiveness are in order of pineapple stubble mulching with whole amount of fertilizer application, 2/3 amount and 1/2 amount of fertilizer application. Except the treatment of pineapple stubble vertical mulching, all the treatments in the second renewal crop of pineapple orchard showed more deterioration soil physico-chemical than the first renewal crop of pineapple orchard. There were significant differences among the treatments in respect to soil organic matter, available P2O5, and exchangeable K2O. The treatments of pineapple stubble vertical mulching with whole amount or 2/3 amount fertilizer application showed the best results. In respect to soil apparent specific gravity, porosity and hydraulic conductivity, there were significant differences in the early stage of this experiment and plowing treatment showed the best. But there were no significant differences in late stage of this experiment. The results of testing for soil dispersion ratio, aggregate stability, and moisture retention characteristics showed that treatments of pineapple tubble mulching with whole amount of fertilizer application, and with 2/3 amount or 1/2 amount of fertilizer applications were better than clean cultivation. All the treatments in the second renewal crop pineapple orchard, except the treatment of pineapple stubble vertical mulching with whole amount of fertilizer, showed poorer yielding than the first renewal crop of pineapple orchard, and the treatments of pineapple stubble vertical mulching with whole amount of fertilizer or 2/3 amount of fertilizer showed the higher yielding than other treatments. In conclusion, the treatment of pineapple stubble vertical mulching showed the best results for controlling soil loss, maintaining soil moisture content, improving soil physical characteristics and the fertility of soil which could improve pineapple growing and yielding. The other methods of pineapple stubble mulching or clean cultivation showed no good results. In the slopeland like in this experiment, the first renewal crop of pineapple orchard can use pineapple stubble mulching with 1/3 reduction of fertilize rapplication. But in the second renewal crop, it is necessary to use pineapple stubble ver-tical mulching with whole amount of fertillizer application to prevent the reduction of yielding. Using this method, the pineapple can be grown in slopeland continuously and will maintain the good yielding
(42(1):53-63)Effects of Different Cover Crops on Soil Properties and Soil and Water Losses on Sloping Litchi Orchard
No full text本試驗之目的在比較坡地荔枝園不同覆蓋作物對土壤性質、水土和地表養份流失及主作物生育之影響情形，並觀察覆蓋作物生長習性，以瞭解不同覆蓋作物之水土保持效益，藉以選取坡地荔枝園較適用草種及提供土壤管理和保育設計參考，並作為推廣依據。試驗區設置於本分所11°西北向壤土之坡地上，採逢機完全區集設計，八處理二重複，八個處理包括：（A）因地毯草覆蓋；（B）自然雜草覆蓋；（C）兩耳草覆蓋；（D）清耕對照區；（E）狗牙根覆蓋；（F）假儉草覆蓋；（G）類地毯覆蓋；（H）百喜草覆蓋。茲將試驗結果摘要如下：
（一）各處理水土流失測定結果以百喜草覆蓋區較低，假儉草及狗牙根覆蓋區次之，三者之間差異不顯著，而以清耕對照區較高。
（二）各處理地表逕流水中養份流失量和水土流失量大小趨勢相近，以百喜草覆蓋區較低，狗牙根及假儉草覆蓋區次之，清耕對照區較高。
（三）覆蓋率調查結果顯示：各處理以百喜草及假儉草覆蓋情形較佳，雜草侵入亦較少。
（四）旱季土壤水分含量測定結果，覆蓋區均較清耕對照區高，而不同覆蓋作物處理間差異不顯著。兩季土壤水分含量以百喜草覆蓋區較高，假儉草覆蓋區次之，清耕對照區較低。
（五）根據土壤團粒體積中數粒徑、導水率、假比重、分散率、孔隙率、滲透率及土壤硬度等測定結果知各處理以百喜草及假儉草覆蓋區土壤物理性較佳，清耕對照區較差。
（六）土壤化學性測定顯示：土壤有機質及有效態磷，在覆蓋處理區均有增加現象，各處理以假儉草及百喜草覆蓋區較高，而清耕對照區則有減少現象，土壤交換性鉀含量，各處理區均有減少現象，覆蓋區均較清耕對照區高，而不同覆蓋作物處理間差異不顯著。
（七）荔枝生育調查結果，各處理以類地毯草、假儉草及兩耳草覆蓋區較佳，三者之間差異不顯著，而以自然雜草覆蓋區較差。
綜上所述，在與本試驗各項條件近似的11°坡地荔枝園於山邊溝間距範圍內採用百喜草或假儉草均能有效控制水土及養份流失，改善土壤理化性，而且覆蓋良好，雜草較難侵入為理想的覆蓋作物，值得推行。
To select the best cover crop for litchi orchards on slopeland, the experiment was done in 1987-1992 to determine the effects of different cover crops on the soil properties, soil and water losses, litchi growth and growth and development of cover crops. Randomized complete block design was adopted with two replications and eight treatments. The results obtained are summarized as follows;
1. The trestments of cover with bahia grass and cover with centipede grass had the minimum soil and water loss, whereas the clean cultivation plot had the maximum.
2. The least amount of nutrient loss in run-off water was found in the plot covered with bahia grass; that covered with centipede grass, the second and largest amount was found in clean cul-tivation plot.
3. Best coverage was observed in the treatments of cover with bahia grass and cover with centipede grass.
4. The soil moisture content during the wet season indicated that higher amounts were found in the plots of cover with bahia grass and cover with centipede grass, and the lower amount was found in the clean cultivation plot.
5. The median diameter of aggregates, bulk specific gravity, dispersion ratio, porosity, hardness, and hydraulic conductivity of the soils were found to be the best in the treatments of cover with bahia grass and cover with centipede grass. In grass cover plot, increases in organic matter contents and available P were also measured.
6. The treatments of cover with carpet grass and cover with centipede grass give the best litchi growth.
7. Based on the aforementioned results, the treatments of cover with bahia grass as well as cover with centipede grass can provide soil erosion control effectively by full coverage, improve soil ghysical and chemical properties, and thus excellent effect for soil conservation. Therefore, for sloping litchi orchards, the most effective and economical conservation practice is to combine these cover crop treatments with hill-side ditching
(41(1):70-78)Study on Bahia Grass Covering and Mulching for Mango Orchards on Steep Slopeland
No full text本試驗之目的在比較陡坡地芒果園百喜草不同覆蓋及敷蓋方式對水土及地表養份流失、土壤理化性質和芒果生育等影響情形，以明瞭百喜草覆蓋及敷蓋方法在陡坡地芒果園中之坡度限制及其水土保持效益，並確立陡坡地芒果園最經濟有效的水土保持方法，期提供陡坡地芒果園土壤管理和保育設計參考作為推廣之依據。本試驗包括四個處理：（一）百喜草全園覆蓋及敷蓋；（二）百喜草帶狀覆蓋及敷蓋；（三）清耕區；（四）對照區（未種植芒果）。茲將試驗結果摘要如下：
（一）各處理水土流失測定結果均以百喜草全園覆蓋及敷蓋處理區較低，百喜草帶狀覆蓋及敷蓋處理區次之，二者之間差異不顯著，而以清耕區及對照區較高，均與前二處理區呈極顯著的差異。各處理地表逕流水中養份流失量和各處理水土流失量大小趨勢相同。逕流水中養份濃度以施肥後較高。
（二）根據土壤團粒體積中數粒徑、分散率、飽和導水率、假比重、孔隙率、滲透率及保水特性等各項測定結果顯示：百喜草覆蓋部份之土壤物理性較佳。土壤有機質含量以百喜草覆蓋部份較高，土壤交換性鉀及有效磷含量則以百喜草敷蓋部份較高。清耕區及對照區土壤理化性均較差，因水土及養份嚴重流失所致。
（三）旱季各處理土壤水分測定結果，以百喜草敷蓋部份較高，清耕區及對照區較低。雨季各處理土壤水分含量則以百喜草覆蓋部份較高，仍以清耕區及對照區較低。
（四）百喜草全園或帶狀覆蓋及敷蓋處理區之覆蓋情形良好，覆蓋率均達90％以上。
（五）國各處理芒果生育調查結果，以百喜草帶狀覆蓋及敷蓋處理較佳，清耕區較差。
（六）綜上所述，在與本試驗各項條件近似的25°陡坡地芒果園於山邊溝間距範圍內採用百喜帶狀覆蓋及敷蓋處理，兼具覆蓋與敷蓋的優點，能有效控制水土及養份流失，減少旱季土壤水分之蒸發，且有利於土壤理化性質之改善及芒果之生育，為理想的陡坡芒果園經濟有效的水土保持方法。
The purpose of this experiment is to find out the effect of bahia grass covering and mulching on soil and water loss, on soil physical and chemical properties, and on mango growth for finding the most effective and economical method of soil conservation in steep mango orchards. The results obtained are summarized as follows:
1. The trearments of covering and mulching with bahia grass and stripping and mulching with bahia grass hab the minimum soil and water loss, whereas the control plot had the maximum.
2. The median diameter of aggregates, bulk specific gravity, dispersion ratio, porosity, and hydraulic conductivity of the soil were found to be the best in bahia grass covering treatments. The amount of organic matter was the highest in bahia grass covering treatments. Bahia grass mulching treatments increased available P and exchangeable K.
3. During the dry season, soil moisture content in the treatment of stripping and mulcheing with bahia grass was higher than that of in amy other treatnent.
4. Best coverage was observed in the treatments of covering and mulcheng with bahia grass and stuipping and mulchein with bahia grass because of vigor growth of bahia grass.
5. The treatment of stripping and mulching with bahia grass gives the best mango growth.
6. Based on the aforementioned results, the treatment of stripping and mulcging with bahia grass could effectively control the soil and water loss, reduce evaporation loss of soil moisture, improve soil physical and chemical properties, and provide full coverage and excellent effect for soil conservation. Therefore, for steep mango orchards the most effective and economical conservation practice is to combine this treatment with hillside ditching
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
(37(1):58-67)Studies on the Methods of Soil Conservation on Slopeland for Summer Vegetable Production
No full text本試驗設置於鳳山熱帶園藝試驗分所坡度11°（20％）東南向砂質壤土的坡地上。其目的在比較坡地夏季蔬菜園不同水土保持方法對水土流失控制效果，以及對土壤水分，土壤理化性和蔬菜生育之影響情形，以探求最經濟有效的水土保持方法，提供坡地夏季蔬菜園土壤管理及保育設計參考。本試驗包括一、內斜式平台增段；二、百喜草帶狀覆蓋及敷蓋；三、百喜草條帶及戀風草敷蓋；四、無處理清耕對照區等四處理。
（一）各處理水土流失測定結果均以百喜草條帶及戀風草敷蓋處理區較少，百喜草帶狀覆蓋及敷蓋處理區次之，內斜式平台增段處理區再次之，惟三者之問差異不顯著，而以無處理清耕對照區較多與其他處理區差異極顯著。
（二）各處理地表逕流水中養份流失量和水土流失量有大小相同之趨勢，逕流水中養份濃度以施肥後較高。
（三）旱季各處理土壤水分測定結果，以戀風草敷蓋區較高，無處理清耕對照區較低。雨季各處理土壤水分含量則以百喜草覆蓋區較高，仍以無處理清耕對照區較低。
（四）土壤化學性測定結果顯示：百喜草條帶及戀風草敷蓋處理區較佳，無處理清耕對照區較差，因水土及養份流失嚴重所致。
（五）根據土壤團粒平均粒徑、飽和導水率、假比重、分散率、孔隙率及土壤保水特性測定結果顯示：各處理以百喜草覆蓋較佳，而以無處理清耕對照區較差。
（六）本試驗結球白菜（夏陽品種）種植於高屏地區海34公尺之坡地，高溫多濕，產量不及高冷地。各處理以百喜草條帶及戀風草敷蓋處理區較高，無處理清耕對照區較低。
（七）根據各項綜合分析結果顯示：百喜草條帶及戀風草敷蓋處理對控制水土及養份流失，減少旱季土壤水分蒸發，改善土壤理化性，提高結球白菜產量之效果有較其他水土保持處理為佳之現象及趨勢，尤以旱季土壤水分含量，土壤有機質及有效態鉀含量與其他處理間差異達顯著水準。故在與本試驗區各項條件近似的20％坡地夏季蔬菜園採用本方法較佳，尚適於農機作業，符合省工經營原則，為一種簡易經濟有效的水土保持方法。
Field experiment was conducted on 20% slopeland with sandy loam soil facing southeastern direction at the Fengshan Tropical Horticultural Experiment Station. The purposes of this experiment were to compare the effects of various conservation methods on soil erosion control, soil moisture content, soil physico-chemical properties and vegetables production and to find out the most effective and economical method of soil conservation on slopeland for Summer. vegetable production. Four treatments including (A) reverse slope terrace;(B) strip covering and mulching with bahia grass; (C) strip covering and mulching with bahia grass and weeping love grass mowed for mulching; (D) cleancultivation were designed in this experiment, and the results were summarized as follows
1. The least amount of water run-off and soil loss were found in the plot of strip covering and mulching with bahia grass and weeping love grass mowed for mulching. The next was the plot of strip covering and mulching with bahia grass, and the worst was found in the plot of clean cultivation.
2. Amounts of nutrient loss in runoff water in each treatment were proportional to those of run-off and soil loss . The result also indicated that the higher concentration of nutrients in runoff water was found immediately after the fertilizer application.
3. The moisture contents of soil during the dry season indicated that the higher amount was found in the plot of mulching with weeping love grass, and the lower amount was found in the plot of clean cultivation. The moisture contents of soil during the wet season indicated that the higher amount was found in the plot of covering with bahia grass, and the lower amount was found in the plot of clean cultivation.
4. The soil chemical properties indicated that the best treatment was found in the plot of strip covering and mulching with bahia grass and weeping love grass mowed for mulching, and the worst one was found in the plot of clean cultivation.
5. Based on the record of mean size of soil aggregate, hydraulic conductivity, apparent specific gravity, dispersion ratio, and porosity, the best physical properties of the soil was found in the plot of strip covering with bahia grass, and the worse one was in the plot of clean cultivation.
6. Chinese cabbages (cv. Hsia yang) were planted on the slopeland (34m above sea level) of kaopin area, the yields were inferior to
those grown in cool area. The highest Chinese cabbages yield was recorded on the plot of strip covering and mulching with bahia grass and weeping love grass mowed for mulching, and the lowest chinese cabbages yield was on the plot of clean cultivation.
7. Based on the aforementioned results, the treatment of strip covering and mulching with bahia grass and weeping love grass mowed for mulching which can afford to control the water, soil and nutrient loss effectively, reduce evaporation loss of soil moisture content improve soil physico-chemical properties and higher yields was better than any other treatment, and it is worth to be adopted as the ideal method of soil conservation on 20% slopeland for summer vegetable production
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
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
- …
