芝麻饼肥与鸡粪有机肥不同混用量对烤烟生长、质量和经济效益的影响

本文在常规施肥的基础上配施芝麻饼肥和鸡粪有机肥,研究不同混用量对烤烟生长、质量和经济效益的影响。结果表明：纯施芝麻饼肥不利于烟株早生快发,烟株成熟期推迟,生育期延长,且大田农艺性状、经济效益与化学成分协调性均较差。本试验中,1125 kg/hm²的鸡粪有机肥,配施375 kg/hm²的芝麻饼肥,效果最好,可改善烤烟的产量和质量,对烟株中后期生长有明显的促进作用,可提高烟叶产量、产值、均价和上等烟比例。施用芝麻饼肥对花叶病与青枯病有抑制作用,对抗赤星病不利。     

基于形态和颜色特征的花生品质检测方法

花生为我国主要的经济作物之一。本文采用基于彩色特征空间和数学形态学的方法,对花生的品质进行了检测:用数码相机微距拍摄获得花生图像,中值滤波与提取边缘后,优选6个颜色特征和7个形态特征对花生进行品质检测,结果表明,和形态特征相比,颜色特征能够更好的分辨不同品质和种类的花生,分辨率达到了实用的要求。     

海峡西岸经济区景观格局特征研究

运用景观生态学的空间格局指数法,结合遥感和GIS技术,研究了海峡西岸经济区(海西区)2008年生态系统组成、景观格局特征以及与环境因子的关系。研究结果表明:(1)海西区主要由森林、草地、农田、水域、城镇和荒地构成,各景观类型高程分布差异显著。(2)森林是海西区的优势景观类型,呈规模化集中分布,草地和农田是海西区重要景观类型,斑块数量最多,分布零散;城镇和荒地的结构特征最差,表明其稳定性差,受人为干扰强烈。(3)水域的景观特征处于中间水平,斑块类型差异显著,但景观整体稳定性较强。(4)降水量、气温等自然因素是影响海西区景观格局的主要因素,人口密度和GDP等人为因素影响相对较弱。     

Web Sources for Researching Agricultural Economics

ABSTRACT

As the recent and ongoing information revolution gradually turns traditional library materials into electronic formats, many agricultural resources have become available online. This selective Webliography covers the major online resources for studying and conducting research in agricultural economics and related fields and includes associations and organizations, databases and articles, dictionaries, directories and search engines, government agencies, industry outlooks, market information, statistics, working papers, news, prices, and miscellaneous resources. Web sites were selected based on the quality of the information and their importance to researchers in the various areas of agricultural economics. Most of the sources are free, with many of them being produced by U.S. government agencies.     

Assessing the statistical training in animal science graduate programs in the United States: survey on statistical training

Statistical analysis of data and understanding of experimental design are critical skills needed by animal science graduate students (ASGS). These skills are even more valuable with the increased development of high-throughput technologies. The objective of this study was to evaluate the perceived statistical training of U.S. ASGS. A survey with 38 questions was shared across U.S. universities, and 416 eligible ASGS from 43 universities participated in this study. The survey included questions on the demographics and overall training, graduate education on statistics, and self-assessment on statistics and career path of ASGS. Several analyses were performed: relationship between perceived received education (PRE; i.e., how ASGS evaluated their graduate education in statistics) and perceived knowledge (PK; i.e., how ASGS evaluated their knowledge in statistics from their education); ranking of statistical topics based on PRE, PK, and confidence in performing statistical analyses (CPSA); cluster analysis of statistical topics for PRE, PK, and CPSA; and factors (demographic, overall training, interest in statistics, and field of study) associated with the overall scores (OS) for PRE, PK, and CPSA. Students had greater (P < 0.05) PRE than PK for most of the statistical topics included in this study. The moderate to high repeatability of answers within statistical topics indicates substantial correlations in ASGS answers between PRE and PK. The cluster analysis resulted in distinct groups of “Traditional” and “Nontraditional” statistical topics. ASGS showed lower (P < 0.05) scores of PRE, PK, and CPSA in “Nontraditional” compared with “Traditional” statistical methods. Several factors were associated (P < 0.05) with the OS of PRE, PK, and CSPA. In general, factors related to greater training and interest in statistics of ASGS were associated with greater OS, such as taking more credits in statistics courses, having additional training in statistics outside the classroom, knowing more than one statistics software, and more. This study provided comprehensive information on the perceived level of education, knowledge, and confidence in statistics in ASGS in the United States. Although objective measurements of their training in statistics are needed, the current study suggests that ASGS have limited statistical training on topics of major importance for the current and future trends of data-driven research in animal sciences.     

辣椒(鲜椒)品种比较试验

以辛香二号为对照,对来自1个研究所和8个公司选育的辣椒新品种进行稳定性、适应性、抗逆性、丰产性等各种经济性状进行比较分析。试验结果表明,青优49、绿帅998、曼迪金条、元辣华帅、元辣红丰5个品种表现比较好,适于在关岭自治县及相同气候条件地区推广。     

The cost of gypsy moth sex in the city

Since its introduction in the 1860s, gypsy moth, Lymantria dispar (L.), has periodically defoliated large swaths of forest in the eastern United States. Prior research has suggested that the greatest costs and losses from these outbreaks accrue in residential areas, but these impacts have not been well quantified. We addressed this lacuna with a case study of Baltimore City. Using two urban tree inventories, we estimated potential costs and losses from a range of gypsy moth outbreak scenarios under different environmental and management conditions. We combined outbreak scenarios with urban forest data to model defoliation and mortality and based the costs and losses on the distribution of tree species in different size classes and land uses throughout Baltimore City. In each outbreak, we estimated the costs of public and private suppression, tree removal and replacement, and human medical treatment, as well as the losses associated with reduced pollution uptake, increased carbon emissions and foregone sequestration. Of the approximately 2.3 M trees in Baltimore City, a majority of the basal area was primary or secondary host for gypsy moth. Under the low outbreak scenario, with federal and state suppression efforts, total costs and losses were $5.540 M, much less than the $63.666 M estimated for the high outbreak scenario, in which the local public and private sectors were responsible for substantially greater tree removal and replacement costs. The framework that we created can be used to estimate the impacts of other non-native pests in urban environments.     

鄱阳湖生态经济区林业生态经济发展模式构建的影响因素分析

从政治、经济、产业发展、生态资源和科技人才等方面分析影响鄱阳湖生态经济区林业生态经济发展模式构建的几大因素,并提出相应的建议.     

林区的经济建设初探

文章通过研究挖掘政策机遇,争取国家更大的政策支持、充分利用森林资源优势,建立林区碳汇交易基地、开发好林区水资源优势等几个方面,对林区经济建设提出了看法,和大家共榷,以图为林区经济建设出谋划策。     

烤烟新品种0522在湘南特征特性研究

为了探讨烟草新品种（品系）在湘南植烟区的特征特性,2013年在湖南省常宁市以K326和云烟87为对照,对烤烟新品种0522进行了示范试验。结果表明：与对照K326和云烟87相比较,从株叶型、农艺性状、经济性状和烟叶的外观质量等综合因子看,0522是表现最好的品种,其植株高达93.8 cm,茎围达8.13 cm,节距达4.67 cm,有效叶适中,叶片较厚,烘烤特性好,单产较高,达2877.2 kg/hm2,产值最高,达64874.9元/hm2（按照当年收购价）,中上等烟比例较大,为92.77%。