我国农业产品的结构性矛盾与调整对策

农业产品结构调整是农业结构调整的首要内容，我国当前农产品总量矛盾基本化解，结构性矛盾凸现，表现在国内和国际两个市场。调整农产品结构可从生产力和生产关系两个层面着手：从生产力层面，需大力推行农产品标准化生产；面向国际市场，大力发展我国具有比较优势的农产品的生产；调整农产品的品种、品质结构，发展名牌农产品等。从生关系层面，要转变农民观念，下决心调整农产品结构；充分发挥政府在农业产品结构调整中的职能，包括发挥政府的经济管理职能，政府为经济服务的职能，政府政策支持经济发展的职能等。     

科学施肥与无公害农产品生产

通过无公害农产品生产对肥料的基本要求的介绍,阐述了无公害农产品生产中肥料使用的几大误区,明确了科学施肥是无公害农产品生产的根本、关键和保证。     

庆平湖的水生植被及其渔业利用

本文分析了庆平湖水生维管束植物的种类组成，植被类型，生物量及其渔业利用潜力。该湖水生维管束植物共有１４科１６种，优势种为芦苇，菹草，狭叶香蒲，小茨藻等。植被类型可划分为三个亚型，全湖有７个主要植物群丛，水生植物总生物量为４９６８ｔ，以植物生产量计草食性鱼类年生产力约为１３３８２．５ｋｇ。并对该湖水生植被特点及渔业利用问题进行了讨论。     

Winners and losers among stream fishes in relation to land use legacies and urban development in the southeastern US

The southeastern United States is a center of aquatic species diversity and endemism in North America, but many taxa are imperiled or in decline. Proactive conservation strategies depend on developing sensitive measures of ecological response to environmental degradation early in the process. In the southern Appalachian highlands, much of the region has reforested following extensive logging and agriculture in the last century, but recently exurban development has surged. Patterns of aquatic ecosystem response to these changes were examined in 36 watersheds along a gradient of forest cover from moderately to heavily forested. A linear combination of watershed-scale measures reflecting the extent contemporary forest cover, the trajectory of forest cover change over time, and building and road density were stronger predictors of fish assemblage composition than topographic features. A measure of biotic homogenization relating the abundance of endemic highland fishes to abundance of broad-ranged fishes was sensitive to the gradient of anthropogenic disturbance. Across the watershed disturbance gradient, cosmopolitan species were clear winners as forms unique to the Appalachian highlands were lost. Similar measures of homogenization may be suitable elsewhere for tracking early warning signs of ecosystem stress, particularly in regions with significant endemism. Quantification of the homogenization process in response to urban development and other stressors is a promising avenue for proactive conservation, land use planning, and sustainable development efforts.     

Effects of nitrate‐, ammonium‐, and organic‐nitrogen‐based fertilizers on growth and yield of tomatoes

Mineral and organic fertilizers contain different forms and amounts of nitrogen (N), which can affect yield and product quality. The aim of this study was to determine appropriate amounts of N applied as nitrate (NO ), ammonium (NH ), and organic N (a mixture based on chicken manure) for optimal growth and quality of tomatoes. A pot experiment with sand as substrate was established in a greenhouse with six‐week‐old tomato plants (Lycopersicon esculentum Mill. cv. “Armada”). Nitrogen was applied in nutrient solutions at different NO : NH ratios combined with different chloride levels (NO ‐dominated, NO = NH at low Cl^–, NO = NH at high Cl^–, and NH ‐dominated, respectively) or as organic N at four N‐application rates (250, 500, 750, 1000 mg N plant^–1 week^–1). No significant differences in shoot biomass and yields of red tomatoes were observed between NO ‐ or NH ‐fed plants. Nitrogen rates above 750 mg N plant^–1 week^–1 did not significantly increase marketable fruit yield, but enhanced shoot‐biomass production. The NH ‐N‐dominated treatments (which also had high Cl^– concentrations) showed increasing incidence of blossom‐end‐rot (BER)‐infected fruits. In the organic‐N treatments, shoot‐biomass production and yields were lower than in the inorganic‐N treatments, but fruit quality was good with few BER‐infected fruits. The results show that with a total N supply below 750 mg N plant^–1 week^–1, NH can be used as equivalent N source to NO , resulting in equivalent yields of marketable fruit under the conditions in this experiment.     

天然产物对红火蚁的生物活性研究进展

红火蚁是一种极具危险性的入侵物种,在入侵区给人民群众的身体健康带来严重威胁。目前主要利用人工合成的化学药剂防治红火蚁。然而,长期大量使用化学药剂会导致红火蚁产生耐药性和破坏生态环境等不良影响。近年来,越来越多的研究发现天然产物对红火蚁具有良好的触杀、驱避和熏蒸作用。本文就天然产物对红火蚁的生物活性及其开发为饵剂、触杀型药剂和驱避剂等的潜力以及应用效果进行简要总结与讨论,以期为红火蚁的绿色防控提供参考。     

Formulation and characteristics of new recipes of Egyptian patti beans (Falafel)

New recipes of Falafel were formulated and evaluated regarding acceptability, proximate chemical composition and nutritive value. Soybean meal and/or cotyledons were used to substitute for faba bean at different levels (i.e. zero %, 20%, 40%, 60%, 80% and 100%. Data indicated that blends of faba bean (20%) and soybean meal and/or cotyledons (80%) were the most acceptable recipes compared to the control (100% faba bean) as well as the other substitution levels. Blending soybean with faba bean led to appreciable improvement in some essential amino acids. The in vitro digestibility for soybean blends were comparable to the control.     

恢复黄麻生产 开发黄麻新产品

黄麻在我国具有近千年种植历史，尽管作为传统包装材料使用正居于次要地位，但由于黄麻纤维具有优质、可降解特性，我国麻纺科技人员及企业正在开发新产品，如高支黄麻纱、布；黄麻／棉、黄麻／化纤、黄麻／羊毛、黄麻／丝等混纺高档产品，以及汽车、装饰等产业用品。许多企业正呼吁恢复我国黄麻种植，以减少对孟加拉进口黄麻的依赖。     

中国省际间农畜产品虚拟水流动合理性评价与调控研究

为探究区域虚拟水流动适宜性与流动现状之间的匹配度, 提高我国水资源配置效率, 优化农畜产品生产空间布局, 从水资源、土地资源、农业发展基础、社会经济发展水平和生态环境5个方面构建了中国各省农畜产品虚拟水资源流动适宜性评价指标体系, 运用综合加权求和方法, 计算农畜产品虚拟水资源流动适宜性。并在此基础上, 结合农畜产品虚拟水流动现状, 提出农畜产品虚拟水流动合理性的概念, 构建定量评价模型, 计算中国省际间农畜产品虚拟水资源流动合理性指数。结果表明: 农畜产品虚拟水适宜输出地较适宜输入地多, 且多位于内陆, 西藏、黑龙江、内蒙古农畜产品虚拟水输出适宜性指数大, 北京、天津、上海农畜产品虚拟水输入适宜性指数位居前三; 影响各省农畜产品虚拟水流动适宜性指数大小的原因各异; 全国各省农畜产品虚拟水流动合理性整体水平不高, 合理性指数小于1的仅有14个省, 虚拟水流动较合理的有上海、山西、吉林等省, 其合理性指数分别为0.16、0.21、0.23, 最不合理的为贵州, 其合理性指数高达4.84, 其次是河南、宁夏, 其合理性指数分别为4.18、4.04; 合理性的分布没有明显地域规律, 不同程度的合理性杂乱分布, 没有明显的南北分异或东西分异。最后, 根据各省农畜产品虚拟水流动适宜性以及流动现状, 提出农畜产品虚拟水流动调整策略, 调整类型大致分为控制输出型、鼓励输出型、控制输入型、鼓励输入型、转换输入型和转换输出型6种。宁夏、内蒙古、新疆、黑龙江、河南和吉林属于控制输出型, 西藏、青海、安徽应增加其虚拟水输出量, 福建、浙江、重庆、广州应减少其虚拟水输入量。上海、北京、天津、山西、江苏和陕西6省市农畜产品虚拟水输入现状水平低于其输入适宜性水平, 应该增加其虚拟水输入量。     

发展中国与东盟水产品贸易研究

文章从中国-东盟自由贸易区的建立，分析了其对中国水产品贸易的促进作用以及我国与东盟水产品贸易面临的冲击和挑战；提出了调整产业结构与出口产品结构、加强合作多元化、加快渔业科技进步、发挥政策主导作用等建议与措施。