基于数据包络分析法对山东耕地产出效率及影响因子研究

将山东省内各辖市的耕地生产系统当作决策单元,利用各决策单元存在的差别,采用数据包络分析方法(DEA),对2004年到2013年内所采集的数据进行测算评价;运用Tobit回归模型分析耕地产出效率的影响因素。结果表明越是在经济发达的地区,农业生产大都存在不足的现象,扩大经营规模是弥补动力不足,提升生产效率的有效途径。     

不同种植密度对周单8号玉米产量及农艺性状的影响

[目的]探索周单8号适宜的种植密度。[方法]试验设置了7个密度处理,3次重复,研究不同种植密度对周单8号产量及农艺性状的影响。[结果]随种植密度的增加,周单8号玉米产量呈先增后减的趋势,种植密度在6.00万株/hm2时,产量最高为9148.15kg/hm2,回归方程为Y=3392.18476+1881.396667X-159.3183069X2。随着周单8号种植密度的增加,其穗位高、株高、空秆率上升,双穗率和茎粗下降,倒折倒伏率不变。[结论]周单8号最佳种植密度为5.85万株/hm2,最高理论产量为8946.08kg/hm2。     

审时度势依靠科技恢复发展棉花

在世纪之交,我国棉花生产、消费出现回升趋势。本文就如何恢复发展棉花进行分析并提出对策。     

南京地区高档花卉生产现状·制约因素及对策分析

以南京地区蝴蝶兰（Phalaenopsis）和风梨（Ananas）生产为例,对生产成本进行分析,指出能耗、人工和生产技术是限制花卉生产发展的重要因素,提出充分利用地域资源、合理布局、提早催花处理等措施能降低成本,促进温室花卉生产企业的发展。     

美国大豆生产、育种及产业现状

美国是目前世界上最大的大豆生产国,大豆种植面积(每年3 000万hm2 以上)和总产(每年近8 000万t)均占世界的1/3左右;在大豆高产育种、品质育种、抗性育种等方面研究均居世界领先地位.分子育种已成为美国大豆品种改良的重要手段,美国第一代转基因大豆育成引领了世界大豆育种方向.研究借鉴美国大豆生产、育种与推广的经验...     

Constraints and possibilities for developing aquaculture

World aquaculture production in 1990 reached some 15 million tonnes, and predictions indicate that future production will reach 19.6 million tonnes by 2000, 37.5 million tonnes by 2010, and 62.4 million tonnes by 2025. Meanwhile, world fisheries production from capture will remain stable at about 100 million tonnes. Thus, all future increase in seafood supplies will have to come from aquaculture.Possibilities for development of aquaculture exist in a number of areas around the world. Technology and natural conditions determine the choice of sites and species to be produced, but current research indicates that a number of new species will be added to the present aquaculture production in the coming years. However, well-known species such as carp, tilapia, trout, salmon, turbot, halibut, cod, and sturgeon will be the most important in the immediate future. Among the crustaceans, shrimp will continue to be an important item, as will various kinds of gastropods and bivalves.Regions with a particular suitability for development of aquaculture include Africa, Asia, and Latin America. Freshwater aquaculture may also be developed on a larger scale in the former Eastern European countries, including the former Soviet Union, but here (and in Africa), political and economic constraints will slow down development for the next decade. A major constraint for development of aquaculture in Africa is the lack of infrastructure, as well as political problems, slow or deficient bureaucracies, and to some extent pollution. In Eastern Europe, development will be hindered by the lack of capital, and uncertainty about the political and economic development. Eastern Europe also has a major environmental problem, which may limit growth within this field. In Asia, space and availability of suitable sites are becoming a problem, as are pollution, diseases, and in some cases overproduction.A general constraint to global development of aquaculture may be price fluctuations, which affect the investment willingness of interested investors. This question must be seen in connection with the economics of operation. As new species are being launched, there is usually a short period of high profits, followed by a period of price reductions, and the collapse of several operators. After such turbulence, serious operators with proper management survive, and go on to operate a reasonably profitable business. The mechanism seems to be true for all new business areas, and does create a problem for sustained investor interest in aquaculture development.     

基于因子分析的农业综合生产能力评价——以湖南省为例

从农业综合生产能力的基本内涵出发,构建了基于统计数据的农业综合生产能力指标体系,该指标体系由要素投入规模、要素产出规模、要素产出率、抗灾保产能力、现代化经营水平5个部分14个具体指标组成。基于因子分析方法,运用这一指标体系对湖南省14个市州的农业综合生产能力水平进行了系统的实证分析。结果表明,尽管湖南省农业综合生产能力总体水平呈持续、稳定增长的态势,但区域间农业综合生产能力水平差异显著,在农业综合生产能力水平方面存在很大的提高空间。     

花卉生产经营及其对农民收入的影响分析——基于云南省和广东省的调查数据

通过对中国花卉主产省——云南和广东的实地调研,结果发现：花卉经营收入是农户农业收入的重要组成部分,对农业总体收入会产生明显的影响,花卉生产推动了农业经济结构和农民收入结构的优化。构建计量模型研究得出：花卉的基本要素投入、种植面积以及劳动力投入对花农的花卉收益和总收入会产生正面影响,而花农的生产经验是稳定收入的重要保障,教育水平也会制约着花农的生产经营和效益水平。     

我国稻田镉污染现状·危害·来源及其生产措施

介绍了我国稻田镉污染的现状,综述了稻田镉污染的危害及其来源,并从选择镉低积累的水稻品种、合理施用肥料、水分调控、控制稻田镉污染和选择非镉污染稻田等方面提出了降低稻田镉污染的生产措施.     

新疆盐渍化土地种植耐盐小麦效应分析

在新疆盐渍化土地种植耐盐冬小麦试验示范结果表明，盐碱弃耕地和盐碱荒地种植“石冬5号”耐盐冬小麦，脱盐效果较好，比种植其他作物有较高的经济效益和社会效益；结合种植深根系牧草，有利于改良低产盐渍化土地，提高土地生产力，具有现实的增产效益和长期生产效应；实行作物轮作倒茬，可防止耕地再度次生盐渍化，为提高盐渍化土地生产力寻求了有效途径。