The Current Core Literature of the Agricultural Sciences

ABSTRACT

A five year project to identify the most vital or core literature of the agricultural sciences was undertaken with results for the advanced countries as well as the Third World countries. Citation analysis and other bibliometric techniques were used to identify the most valuable literature for university-level instruction and research. Monographs in seven sub-disciplines of agriculture were evaluated by researchers resulting in a composite list of 8,400 volumes and in 363 core journals. Methods of analysis, evaluation techniques, and end products are described. Four of seven books describing the literature of agriculture have been published. A final product will be the transfer of the full text of the monographs and the journals for a five year period onto compact disk for use in the Third World. Because of copyright and other restrictions, the estimated 280 disk library will not be available to developed countries.     

Mapping the Literature of Food Science Revisited: 2003–2005

ABSTRACT

After reviewing previously published literature in citation analysis and literature mapping, this study mapped the literature of food science and explored the relationships found within it. Using articles published in the Journal of Food Science from 2003 through 2005, a stratified random sample of citations was studied to yield a ranked list of the thirteen most frequently cited journals, which formed a core set for further analysis. Using the Science Citation Index and a standard statistical package (SPSS₁₃), a two-dimensional map was created, relationships between the journals were studied, and the discipline of food science was explored. The study is an extension of previously published research covering the years 2000–2002 and attempts to analyze and compare the results across time frames.     

Identification and genetic relationships of kenaf (Hibiscus cannabinus L.) germplasm revealed by AFLP analysis

Kenaf (Hibiscus cannabinus L.) is one of the world's most economically important fiber crops. In order to identify different varieties, and investigate its diversity and genetic relationships, twenty-three kenaf accessions and two accessions of its relative, roselle (H. sabdariffa var. altissima), were analyzed by morphological characterization and AFLP fingerprinting. It is very difficult to identify kenaf accessions based merely on morphological characters, due to their limited variation. For the AFLP study, a total of 505 polymorphic markers (out of 560) were produced by six selected AFLP primer combinations. The AFLP fingerprinting was effective in identifying all kenaf accessions included in the study. Kenaf and roselle are independent species with close relationships, and great genetic diversity was also detected among the kenaf accessions with different origins, based on the analysis of the AFLP markers. The AFLP analysis strongly supports the opinion that kenaf originated in Africa. It also demonstrated that the dissemination of kenaf was from Africa through Asia to Central and North America.     

Mapping the Literature of Food Science Using Co-Citation Analysis

ABSTRACT

This study mapped the scholarly literature in the discipline of food science using co-citation analysis and explored the relationships found within this literature. Using the Journal of Food Science, an examination of a random sample of its articles published from 2000 to 2002 yielded a ranked list of frequently-cited journals. The top thirteen most frequently-cited journals formed a core set for further analysis. Using the SciSearch online database and a standard statistical package (SPSS), a two-dimensional map was created, relationships between the journals were studied, and the discipline of food science was explored. Food science journals tended to be either industry-specific (e.g., dairy science) or industry-general. The journals also tended to focus on either “pure” science (e.g., chemistry) or on applied science and technology. Of the thirteen journals mapped, six fell within the area of pure science, while four were in the area of applied science. Interestingly, three journals fell on the axis line dividing the two. At the same time, seven journals had the characteristics of being industry-general, while six were more industry-specific. The results are consistent with previous indications of the interdisciplinary nature of the field of food science, drawing as it does from many fields such as chemistry, microbiology, engineering, and agricultural science.     

农田生态系统分析与农业可持续发展

农田生态系统分析是以农民为中心,由自然科学工作者、社会科学工作者、决策管理人员、土地规划人员和农民共同参与,通过研究农民实际生存的农业自然环境、社会、文化、经济环境,结合考虑农民的意愿与抉择,提出解决农田生态系统问题的一种动态过程与方法,其基本目标是实现中小尺度上的农业可持续发展。农田生态系统分析一般包括５个阶段：问题诊断与分析、研究方案设计与规划、方案验证与评价、结果评价阶段和建议与推广应用。据此,提出适宜于不同农业生态系统的可持续发展方案,为区域乃至国家范围的可持续发展提供决策依据。该文分析了农田生态系统分析的概念、起源、目标、特征和研究过程。     

基于WoS平台的中外水土保持研究计量学比较分析

[目的]对比分析中外水土保持研究的文献增量趋势、学科分布、机构和作者的合作网络以及水土保持研究热点,为中国相关领域学者、科研机构以及政府管理部门在加强国际科研合作以及关注农业农学问题研究等方面提供科学有益的参考。[方法]以Web of Science(WoS)数据库1986—2015年中外水土保持文献数据为对象,以知识图谱的方式,运用CiteSpace计量学分析软件对引文数据进行了分析和处理。[结果]中外水土保持研究文献总量均呈稳定增长趋势;美国、中国、澳大利亚占据了文献产出国家排名的前3位,欧洲高产国家最多;总体学科领域跨度较大,新兴学科增长明显;中外机构合作联系紧密,树状图谱枝杈丰满,形成了以中国、美国为重要产出节点的合作生态链;比利时的佩森(Poesen J)、戈韦尔(Govers G)等学者产出最多,且在各国学者合作中起到了重要的桥接作用。[结论]中外在水土保持研究热点上十分接近,土壤侵蚀、径流和建模是中外频次最高的研究热点关键词。     

Segmenting Green Tea Consumers by Purchase Motivation in South Korea

Since the 1990s green tea consumption in South Korea has been gradually increasing because consumers consider green tea as beneficial to health. It is, therefore, necessary to know the factors influencing each motivational cluster according to sociodemographic characteristics. This study aims to obtain an empirical understanding of the green tea market by using a segmentation approach to provide better information for green tea marketers in Korea. A self-administered survey was obtained from 595 consumers in Seoul, Korea. Four distinct segments from cluster analysis were identified based on motivation: low motivated (18.0%), social seekers (35.7%), want-it-all (25.3%), and refreshment (21.0%). A multinomial logit regression analysis was used to identify the characteristics of consumers who are most likely to opt for a suitable motivation segment. Results indicated that the determinants of consumer motivation are age, occupation, price, company, and purchasing place.     

在伊朗中部源于第三纪沉积物的土壤上影响坡缕石的发生因素研究

Limited information is available on the distribution and origin of palygorskite in soils developed on Tertiary sediments as the major soil parent materials in central Iran and other Middle Eastern countries. The objectives of this study were to determine the distribution and origin of palygorskite in soils developed on Tertiary sediments, and to identify the major soil properties that influence palygorskite distribution in the soils studied. Sixteen soil profiles developed on Paleocene, Eocene, Oligocene, Oligocene-Miocene, Miocene and Pliocene sediments were studied by X-ray diffraction analysis, transmission electron microscope, and scanning electron microscopy. Physicochemical characteristics of the soils and sediments including particle size distribution, pH, electrical conductivity, organic carbon, gypsum, carbonates, and soluble Si, Ca and Mg were determined. The principal component analysis was used to establish the relationships between palygorskite and the physicochemical characteristics of the soils studied. Results showed that clay fraction of all the soils in the study area was dominated by palygorskite. The highest amount of palygorskite was found in horizons where simultaneous accumulation of both carbonates and gypsum occurred. Limited amount of palygorskite was found in salic and calcic horizons. Palygorskite seemed to be of eolian origin in the surface horizon of all the soils. Using principal component analysis, the soluble Mg/Ca ratio, pH, soluble Si and gypsum contents were identified as the most important factors affecting the distribution and genesis of palygorskite in the soils studied. Results might suggest the neoformation of palygorskite by precipitation from solutions in which evaporation fluxes were very high. However, palygorskite in soils developed on Tertiary sediments in central Iran seems to be of both inherited and pedogenic origins.     

以栾城试验站为研究基地的科研论文发表情况分析

运用CNKI 和ISI Web of Knowledge 两大数据库的文献计量分析工具, 统计了1981 年到2010 年间在中国科学院栾城农业生态系统试验站开展科学研究的科技论文发表情况。结果表明: 所检索到的过去30 年发表的论文为1 151 篇, 其中中文论文920 篇、英文论文231。1981~2010 年, 年度发表论文数量呈稳步增长趋势, 2001年以前发表的科技论文主要以中文论文为主, 2001 年以后英文论文数量逐年增加, 年均增长速度为22.4%; 中文论文2005 年达到高峰后逐年减少。论文作者单位主要集中在河北、北京、山东等地, 与国外合作单位主要集中在日本、美国。论文的关键词出现频率较高的为: 小麦、水分利用效率、玉米、产量、土壤水分等。开展研究所得到的资助项目主要以国家科研计划项目和中国科学院科研计划项目为主, 其次为地方科研计划项目, 国际合作项目相对较少。论文发表的期刊来源主要为:《中国生态农业学报》、《干旱地区农业研究》、《华北农学报》、《Hydrological Processes》、《Agricultural Water Management》、《Plant, Soil and Environment》、《Irrigation Science》。发表论文的平均引用次数为5.6 次, 引用次数超过100 次的论文为6 篇, 引用次数超过50 次的论文为34 篇。     

Determining the Core Literature of Water: A Citation Analysis of Faculty From New Mexico State University

Facilitating access to journals for a multidisciplinary field of study requires an understanding of the literature used by those researchers. This study examines the journals used for publication and those cited by 85 faculty affiliates of the New Mexico State University (NMSU) Water Science and Education Center (WSEC), a multidisciplinary faculty group with a water research focus. The authors have used information gained from this study to enhance collections and outreach at NMSU. This study also adds to the literature on citation analysis as a tool for informing collection development and management.     

Boron Deficiency Precisely Identified on Growth Stage V4 of Maize Crop Using Texture Image Analysis

The aim of this study was to evaluate the diagnostic imaging approach to identify the deficiency of boron in leaves of maize. The experiment was conducted in a greenhouse under a hydroponic system. The treatments were four levels of boron (B) in solution nutrition (zero, 0.12, 0.24 and 0.60 mg L^?1), combined at V4, V7, and R1 growing stages. Plant parts sampled included index leaf and new leaf to chemical analysis and texture image analysis. Our proposal was to apply these texture analysis and pattern classification schemes to identify the levels of B. Texture methods achieved 98% of accuracy in differentiating between leaves properly fertilized with B, from leaves with deficiency, in V4. In all tests, with index leaf success rate was higher than 80%, and around 90% for the new leaf. The image analysis by texture techniques applied on maize leaves are able to identify boron deficiencies in younger plants.     

Evaluating cost-effectiveness of conservation management actions in an agricultural landscape on a regional scale

Agricultural landscapes are the dominating landscape types in many parts of the world. Land-use intensification and spatial homogeneity are major threats to biodiversity in these landscapes. Thus cost-effective strategies for species conservation in large-scale agricultural landscapes are required. Spatial optimisation methods can be applied to identify the most effective allocation of a given budget for conservation. However, the optimisation of spatial land-use patterns in real landscapes on a large spatial scale is often limited by computational power. In this paper, we present a simplifying methodology for analysing cost-effectiveness of management actions on a regional scale. A spatially explicit optimisation approach is employed to identify optimum agricultural land-use patterns with respect to an ecological-economic goal function. Based on the optimisation results for small scale landscape samples we derive a target- and site-specific cost-benefit function that can be applied to predict ecological improvement as a function of costs and local conditions on a large spatial scale. Thus, it is possible to identify areas where management actions for ecological improvement are most efficient with respect to a certain conservation goal. The fitted function is validated independently. In a case study, we analyse cost-effectiveness of management actions to enhance habitat suitability for three different target species. The approach is flexible and could be applied to a variety of other landscape planning problems dealing with the effective allocation of management measures.     

Simple,Robust Method for Quantifying Silicon in Plant Tissue

Low silicon (Si) content in rice, sugarcane and other Si-accumulating crops can adversely affect crop performance because it creates reduced tolerance to both abiotic and biotic stresses. Assessing the Si status of a crop typically depends upon accurately measuring Si accumulation in plant tissue. Methods involving wet digestion of plant tissue followed by colorimetric determination of Si have proven attractive because they are both rapid and do not require costly, specialized instrumentation. Some popular wet-digestion methods are reported to provide highly variable and inconsistent results. A systematic study to identify and address the sources of variability associated with wet digestion for Si analysis found that modifications that reduce excessive foaming during wet digestion of plant tissue in strong alkali and peroxide significantly reduce variability. Unstable and variable color development associated with the molybdenum blue reaction is a concern in the colorimetric determination of Si in digests. Experiments showed that the inclusion of ammonium fluoride to facilitate the release of polysilicic acid prior to colorimetric determination results in reproducible readings that stabilize within 60 min and remain stable for at least 5 h. With this modification, the accuracy and precision of values obtained colorimetrically are comparable or superior to those obtained by inductively coupled plasma–optical emission spectroscopy (ICP-OES) analysis. A two-phase wet-digestion procedure is described for Si tissue analysis that is robust, accurate, and precise and requires equipment commonly found in most agricultural laboratories.     

高粱KNOX基因家族鉴定及SbKNOX22基因表达分析

KNOX基因家族是植物生长发育过程中所特有的一类转录因子,其在植物的形态建成方面发挥着重要的作用。为研究高粱KNOX基因家族特征及SbKNOX22的表达特性,本研究利用生物信息学和实时荧光定量PCR(qRT-PCR)的分析方法,对高粱KNOX基因家族进行了鉴定和表达分析。结果表明,在高粱中共鉴定到23个KNOX基因(SbKNOX1~SbKNOX23),亚细胞定位显示均定位于细胞核中,氨基酸序列长度介于184~802 aa之间,分子量大小介于20.23~86.14 kDa之间,理论等电点介于7.28~4.76之间,高粱KNOX基因家族蛋白均属亲水性蛋白,分布在8条染色体上。系统进化结果显示,高粱KNOX基因家族分为Class Ⅰ和Class Ⅱ两类;基因结构分析表明,Class Ⅱ类中各亚类家族成员之间的外显子和内含子数量存在较大差异;Motif分析显示,Homeobox KN结构域最为保守。qRT-PCR分析表明,SbKNOX22在高粱叶片中表达,水杨酸处理6 h时表达量最高,PEG 6000和甘露醇模拟干旱胁迫处理0.5 h后表达量开始降低,NaCl胁迫处理9 h时表达量最高。本研究结果为进一步探索KNOX家族在调节高粱生长发育、信号转导和植物激素调控等过程中的作用提供了基础。     

基于VIP模型评估不同全局敏感性分析方法有效性及效率

参数敏感性分析可提高复杂过程模型参数优化及模型应用效率。为评估不同全局敏感性分析方法在筛选农田生态系统模型敏感参数时的有效性及其效率,该研究以VIP (Vegetation Interface Processes)模型模拟华北平原土壤硝态氮为例,对比分析PSUADE (Problem Solving Environment for Uncertainty Analysis and Design Exploration)提供的8种敏感性分析方法在筛选华北平原农田土壤硝态氮敏感参数时的有效性及其效率。结果表明:在验证敏感性分析方法有效性时,Spearman秩相关系数(Spearman’s correlation coefficient,SPEA)法和Gaussian Process (GP)法与其他方法的敏感参数筛选的结果差异较大;多元自适应回归样条(Multivariate Adaptive Regression Splines,MARS)、Delta Test (DT)、Sum of Trees(SOT)法、McKay法、Morris法和Sobol’法能有效筛选出敏感参数。在分析敏感性方法效率时发现,正交阵列(Orthogonal Array,OA)和基于拉丁超立方的正交阵列(OrthogonalArray-BasedLatinHypercubes,OALH)抽样方式最适于多元自适应回归样条法(Multivariate Adaptive Regression Splines,MARS),所需样本量为361。蒙特卡罗(Monte Carlo,MC)抽样方式最适合DT和SOT敏感性分析方法,所需最小样本量分别为425和510;与其他抽样方式相比,OALH抽样更适合McKay敏感性分析方法,需要样本量最少;Morris法和Sobol’法所需最小样本量分别为340和810。对于复杂过程模型,可先选用定性敏感性分析方法以较低的计算成本选择敏感的参数,再进行模型参数优化和不确定性分析。     

基于文献计量的国内外人工林土壤地力研究

为了解国内外人工林土壤地力的研究进展和发展趋势,采用文献计量学方法,以中国知网(CNKI)和Web of Science核心合集数据库相关文献为数据源,利用VOSviewer、HistCite等工具,从国家、机构、作者、研究热点方面对2021年之前的有关文献进行了计量分析.结果表明:国内外该领域年发文量呈逐渐增长趋势,...     

人类活动对太湖地区地表水水质的影响

Taihu Lake region is one of the most industrialized areas in China, and the surface water is progressively susceptible to anthropogenic pollution. The physicochemical parameters of surface water quality were determined at 20 sampling sites in Taihu Lake region, China in spring, summer, autumn, and winter seasons of 2005-2006 to assess the effect of human activities on the surface water quality. Principal component analysis (PCA) and cluster analysis (CA) were used to identify characteristics of the water quality in the studied water bodies. PCA extracted the first three principal components (PCs), explaining 80.84% of the total variance of the raw data. Especially, PC1 (38.91%) was associated with NH₄-N, total N, soluble reactive phosphorus, and total P. PC2 (22.70%) was characterized by NO₃-N and temperature. PC3 (19.23%) was mainly associated with pH and dissolved organic carbon. CA showed that streams were influenced by urban residential subsistence and livestock farming contributed significantly to PC1 throughout the year. The streams influenced by farmland runoff contributed most to PC2 in spring and winter compared with other streams. PC3 was affected mainly by aquiculture in spring, rural residential subsistence in summer, and livestock farming in fall and winter seasons. Further analyses showed that farmlands contributed significantly to nitrogen pollution of Taihu Lake, while urban residential subsistence and livestock farming also polluted water quality of Taihu Lake in rainy season. The results would be helpful for the authorities to take sound actions for an effective management of water quality in Taihu Lake region.     

Modelling mammalian extinction and forecasting recovery: koalas at Iluka (NSW, Australia)

This study investigated the recent demise of a koala population at Iluka in eastern Australia and demonstrates the potential role of population viability analysis (PVA) in the recovery and management of similar small populations. Information about the Iluka population was reconstructed from various sources, including community knowledge, wildlife carer data, and from a radiotracking program. Modelling scenarios were constructed to identify which factors may be critical to the survival of the Iluka population and which management options could provide the most effective means of its recovery. The model suggested that even substantial improvements in mortality and fertility alone do not prevent the modelled population declining towards extinction. Rebuilding of the koala population is likely to require guaranteed regular immigration of animals of both sexes in conjunction with considerable improvements in population mortality and fertility. This highlights the importance of the metapopulation for recruitment, an outcome that was not expected prior to modelling. These modelling outcomes suggest that the management of small, local populations of koalas will need a concerted management effort focusing on multiple causes of population change. Local management actions, such as reducing road deaths and managing habitat and fire, must be accompanied by knowledge of the larger geographical population.     

Variation among Spanish faba beans cultivars: taxonomic and evolutionary implications

Summary Univariate and multivariate analysis were used to examine phenotypic variability within a Spanish faba bean germplasm collection maintained at the Centro de Investigación y Desarrollo Agrario, Córdoba, Spain.The analysis of 158 Spanish faba bean accessions and 12 quantitative traits indicated highly significant differences among botanical groups for 8 characters and among geographic regions for 10 characters. An east to west clinal pattern of variation for some characters was detected.In order to identify the main characters which account for the major variation, the same collection was subjected to principal component analysis for 12 quantitative traits. Reproductive and plant height characters appeared to be the major sources of diversity.To determine the importance of both geographic and botanical variation among the Spanish cultivars, discriminant analysis was applied. According to these analyses, plant height, height of the lowest pod-bearing node, pod length and 100 seed weight, were important traits discriminating among different geographic regions. The main character discriminating among botanical groups was the 100 seed weight.Our results fit in a pattern in which both agroecological and anthropological causes could have played a role in the observed variation. This analysis can help plant breeders in choosing the most favorable accessions in plant breeding.