食品安全问题英文期刊投稿

健康食品 一提起健康食品，人们通常都会马上联想到蔬菜、水果，而视油腥为大敌。实际上，很多肉类、油料作物、动物内脏也对人体健康的维持起到很关键的作用。但直至现时为止，香港或其它西方国家如美国和澳大利亚在法律上并没有对健康食品下定义，而台湾就把健康食品定义为“提供特殊营养素或具有特定之保健功效，特别加以标示或广告，而非以治疗矫正人类疾病为目的之食品”。因此，现时在市场上所谓的健康食品包括食物补充品、功能食品和天然食品等。虽然卫生署及食物环境卫生署监管健康食品上的卷标、营养声称和营养素功能声称，但是消费者委员会曾发现市场上部分产品有夸张失实的声称，更有部分不乎合世界卫生组织的水平。消费者必须查看清楚产品的来源、性质及功能，亦不要尽信售货员的推销，应咨询有关专业人士的意见。全球公认的健康食品生命的营养源牛奶：每100克牛奶含蛋白质3.5克，脂肪4.0克，碳水化合物5克，钙120毫克，磷93毫克，铁0.2毫克，硫胺素0.04毫克，核黄素0.13毫克，尼克酸0.2毫克，维生素A42毫克，维生素C1毫克。牛奶蛋白质中赖氨酸含量仅次于蛋类，胆固醇含量每100克中仅含16毫克。最佳蔬菜：红薯既含丰富维生素，又是抗癌能手，为所有蔬菜之首。其次是芦笋、卷心菜、花椰菜、芹菜、茄子、甜菜、胡萝卜、荠菜、苤蓝菜、金针菇、雪里红、大白菜。最佳水果：依次是木瓜、草莓、橘子、柑子、猕猴桃、芒果、杏、柿子和西瓜。 最佳肉食：鹅鸭肉化学结构接近橄榄油，有益于心脏。鸡肉则被称为“蛋白质的最佳来源”。最佳健脑食物：菠菜、韭菜、南瓜、葱、花椰菜、菜椒、豌豆、番茄、胡萝卜、小青菜、蒜苗、芹菜等蔬菜，核桃、花生、开心果、腰果、松子、杏仁、大豆等坚果类食物以及糙米饭、猪肝等。最佳汤食：鸡汤最优，特别是母鸡汤还有防治感冒、支气管炎的作用，尤其适于冬春季饮用。最佳食油：玉米油、米糠油、芝麻油等尤佳，植物油与动物油按1∶0．5的比例调配食用更好。最佳茶类：绿茶；绿茶有助于防止辐射健康食品具体介绍蔬菜十三鲜 入榜“最佳蔬菜”的有13种，都是我们平时经常会吃到的。 香甜的红薯最让人流连，也许你不一定每天吃，但是红薯里含有丰富的纤维、钾、铁和维生素B6，不仅能防止衰老、预防动脉硬化，还是抗癌能手，所以它被选为蔬菜之首。 北京市食品研究所张嘉芷教授说，日常饮食讲究酸碱搭配，健康人PH值要达到7.3左右，而我们平日吃的肉类几乎都是酸性食品，所以要和碱性食物搭配在一起吃，蔬菜中卷心菜、芹菜、胡萝卜等就是碱性食品，可以多吃一些。 除了上面提到的几种蔬菜，芦笋、花椰菜、茄子、甜菜、荠菜、苤蓝菜、金针菇、雪里红、大白菜也要记得多吃。 九种水果香甜可口 一说到营养就会提到水果，可关于水果的营养价值众说纷纭，人们真是不知道究竟吃哪种水果好了，不过，入榜的九种权威水果倒不可不信。 头号水果就是木瓜，虽然富含维生素C的橘子、柑子也入选了，但是木瓜里的维生素C却远远多于橘子的含量，而且木瓜还有助于消化人们体内难以吸收的肉类，能防止胃溃疡。 肉甜汁美的草莓不但汁水充足，对人体健康还有极大好处，尤其爱美的女孩可要多吃点，因为草莓可以让你的肤色变得红润，还能减轻腹泻。有意思的是，草莓还能巩固齿龈、清新口气、滋润咽喉。而且，草莓叶片和根还可用来泡茶，真可谓“浑身是宝”。 此外，猕猴桃、芒果、杏、柿子、西瓜这几种香甜多汁的水果也跻身最佳食品之列。 荤菜吃出名堂 荤菜虽然脂肪含量比较大，但却是日常饮食中不可或缺的，所以要吃出点名堂来，荤菜也能给身体均衡营养。 进榜的最佳肉食当数鹅肉、鸭肉和鸡肉，张嘉芷教授介绍说，鹅肉和鸭肉的化学结构很接近橄榄油，对心脏有好处，尤其是老人不妨适当多吃点。鸡肉是公认的“蛋白质的最佳来源”，老人、孩子更要及时补充。 吃过肉记得喝鲜汤，最优质的汤非鸡汤莫属，特别是母鸡汤，还有防治感冒、支气管炎的作用，尤其是冬、春季喝效果更好。 养脑巧吃零食 现在用脑过度的人非常多，吃什么最能养脑是这些人最关心的问题，这不，榜上就评出了最佳护脑的食品，还有不少可以当零食吃呢，快来试试吧。 蔬菜中菠菜、韭菜、南瓜、葱、花椰菜、菜椒、豌豆、番茄、胡萝卜、小青菜、蒜苗、芹菜都有补脑作用。此外，核桃、花生、开心果、腰果、松子、杏仁、大豆等壳类零食对脑子也很有好处。 关于垃圾食品垃圾食品，是指仅仅提供一些热量，别无其它营养素的食物，或是提供超过人体需要，变成多余成分的食品。世界卫生组织“通缉”的垃圾食品前三名是油炸食品、腌制食品和加工类的肉食品。虽然这三类食品几乎是我们每顿正餐都会出现的，但摄入过多却会加重身体负担。

Eating SafelyFood safety is very important to us. How can we make food safe? Here’s some advice. First, we shouldn’t go out to eat fast food often. At the restaurant there is also some food that isn’t safe, such as unhealthy oil. Second, we should make food clean before cooking. Remember to boil food. Third, we should buy and eat food carefully. If the food is in bags, we should read instructions and dates carefully. Make sure the food is safe.

学术论文写作用英语写学术论文的目的主要有两个，一是参加国际学术会议，在会议上宣讲，促进学术交流；二是在国际学术刊物上发表，使国外同行了解自己的研究成果，同样也是出于学术交流的目的。 不同的学科或领域、不同的刊物对论文的格式有不同的要求，但各个领域的研究论文在文体和语言特点上都有许多共性。了解了这些语言共性，便会起到触类旁通的作用。 对我国青年学者或学生来说，用英语写作的难点不是没有写作材料，不是不熟悉专业词汇，也不是没有打下良好的英语基础。用英语写论文难，是因为不太了解学术英语的语言特点。关于学术英语写作的语言技巧，我们已在第一部分作了较详细的介绍。此部分讨论学术论文写作的方法，包括学术论文写作中常用的句型结构，我们都在此作较详细介绍，以便读者模仿练习，将写作工作化难为易。 一般来说，一篇完整规范的学术论文由以下各部分构成：Title（标题） Abstract（摘要） Keywords（关键词） Table of contents（目录） Nomenclature（术语表） Introduction（引言） Method（方法） Results（结果） Discussion（讨论） Conclusion（结论） Acknowledgement（致谢） Reference（参考文献） Appendix（附录） 其中Title，Abstract，Introduction，Method，Result，Discussion，Conclusion，Reference等八项内容是必不可少的（其他内容根据具体需要而定）。在这八项内容中，读者最多的是Title，Abstract和Introduction部分，读者会根据这些内容来决定是否阅读全文。也就是说，一篇研究论文赢得读者的多少，在很大程度上取决于Title，Abstract和Introduction写得好坏。因此这三项内容将各分章详细加以讲述。 学术论文的正文一般包括Method，Result，Discussion三个部分。这三部分主要描述研究课题的具体内容、方法，研究过程中所使用的设备、仪器、条件，并如实公布有关数据和研究结果等。Conclusion是对全文内容或有关研究课题进行的总体性讨论。它具有严密的科学性和客观性，反映一个研究课题的价值，同时提出以后的研究方向。 标题的写法论文标题是全文内容的缩影。读者通过标题便能够预测论文的主要内容和作者的意图，从而决定是否阅读全文。因此，为了使文章赢得有关领域里众多的读者，论文的标题必须用最精炼的语言恰如其分地体现全文的主题和核心。本章主要探讨英语学术论文标题的语言特点及写法。 6.1 标题的长度标题单词总数名词数介词数形容词等1） Fire Resistant Steels for Construction： Design， Properties and Microchemistry 9 6 1 2 2） Damping Capacity of Shape Memory Alloy 6 5 1 0 3） Microelectronic Assembly and Packaging Technology： Barriers and Needs 8 5 0 3 14） Solid Oxide Fuel Cell： A Survey 6 4 0 2 5） Progress on Fuel Cell and Its Materials 7 4 1 2 6） Computer Simulation and Experimental Study on Cold Shut During Mold Filling 11 5 2 4英语科技论文中，标题不宜过长，大多为8—12个单词左右。表6.1和表6.2列出了一些学术论文的标题的字数及词性统计资料。 表6.1 学术论文标题中字数及词性统计（一） 标题单词总数名词数介词数形容词等7） On the Fatigue Life Prediction of Spot Welded Components 9 5 2 2 8） Absorbable Implants in Finger Fractures： A Biomechanical and Comparative Study 10 4 1 4 9） Acoustics of Long Spaces： Theory and Application 7 4 l 2 10） Investigation of Air Bags Deployment Forces on Out-of-Position Occupant 7 2 0 11） Semi-Integral Abutments in Bridge Seismic Design 6 3 l 2 12） High Speed Flow Sensor and Fluid Power Systems Modelling 9 7 0 2 13 ） Surface Engineering of Polymers for Biomedical Application 7 4 2 l 14） The Design of User-Oriented Database of Material Performance Based on Client/Server Model 13 7 3 3. 15） Impingement Heat Transfer of Diesel Flames in a Rapid Compression and Expansion Machine 13 8 2 3平均（约）9 5.5 1.5 2来源：中国第三届青年学术会议论文集，材料科学与工程技术。北京：中国科学技术出版社，1998.标题单词总数名词数介词数形容词等1） Use of Vitamin and Mineral Supplements by the Elderly 9 5 2 2 2） Dietary Supplement and Body Image in Female College Students 9 6 l 2 3） Knowledge of Cardiovascular Disease in University Students 7 4 2 l 4） Severe Weather and the Automobile 5 2 0 3 5） Heavy Weight Contenders：a Look at Fat 7 4 1 2 6） A1uminutn：Is It Hazardous to YourHealth？ 7 3 1 3 7） The Use of Technology in Higher Education Programs： a National Survey 11 5 2 4 8） Sustaining the Discussion：Ecology in the Humanities Classroom 8 4 l 3 9） Diversity in the Future WorkForce 6 4 1 l 10） Models of Sustaining Human and Natural Development in an Urban Environment 11 3 2 6 11） Variation in Acorn Production and Chemistry of Two Oak Oak Species with respect to Topography 14 8 5 1 12） Traditional Versus Adult StudiesStudents： the College Experience 8 5 0 3 13） Solving the Food Shortage Problem in Northeast and Northwest Africa Using Hydroponically Grown Peanuts & Solarly Distilled Water 18 10 1 7 14） Impact of Cancer：Coping Process and Quality of Life 9 5 2 2标题单词总数名词数介词数形容词等15） Application of Digital Image Analysis for Helping to Define the Prognosis Of Selected Malignancies 14 6 3 5平均（约） 9.5 5 1.5 3来源：The Ohio Journal of Science Vol. 96（2） 表6.1中列出的是中国科协第三届青年学术年会论文集中15篇英文论文的标题，平均9个单词。表6.2列出的是从The Ohio Journal of Science中随机挑出的15篇论文的标题，平均9.5个单词。要想用有限的字数概括全文的主旨，用词必须仔细斟酌和推敲，选择最简练、最准确、最贴切的词来表达全文的主要内容。 6.2 标题的用词从表6.1和表6.2可以看出，标题中用得最多的是名词（包括动名词），平均占总单词数的50％～60％之高。其中有的标题中80％以上的词为名词。除名词外，用得较多的是介词，有时使用形容词、冠词、连词、副词。 标题是对全文重要内容的高度概括，因此用词要贴切、中肯，不能有任何随意性。为了便于检索，标题中所用的词尽量使用表达全文内容的关键词，下面举例说明标题中关键词的出现率。例1 a.标题：On the Fatigue Life Prediction of Spot Welded Components b.关键词：fatigue spotweld automobile life prediction .疲劳点焊汽车寿命预测b.标题：Computer Simulation and Experimental Study On Cold Shut During Mold Filling关键词：mold filling computer simulation cold shut casting铸件充型计算机模拟冷隔铸造c.标题：Investigation of Air Bags Deployment Forces on Out-of Position Occupant关键词：air bag out-of-position occupant安全气囊离位乘员c.标题：New Fatigue Test and Statistical Method for Metallic Materials Used in Vehicle Transmissions关键词：fatigue test statistical method test specimens疲劳实验统计方法试样分析：例1a中，有4个关键词，在标题里出现了3个，而标题中出现的两个名词词组fatigue life prediction 和spot welded components都是文章的关键词。 在例1b中，有4个关键词，其中3个出现在标题里。标题中用了4个名词词组：computer simulation，experimental study，cold shut，mold filling，其中3个是关键词。 例1c中有2个关键词，在标题里都出现。标题中用了3个名词或名词词组：investigation，air bags deployment forces，out-of-position occupant，其中两个是关键词。 例1d中有3个关键词，其中2个出现在标题里。 从上面四个例子可以看出，标题中的用词多是文章的关键词，明确、精炼，将文章的主要内容予以高度概括。 标题中用得最多的是名词或名词词组，一般不用动词或动词词组。如果用动词，则用非谓语动词形式，如动名词、不定式或分词。 从表6.1和表6.2可以看出，在标题平均9个单词中，有5.5个是名词，占一半以上。除名词外，用得较多的是介词of，in，on等，再其次是连词and和形容词。偶尔也需要用一些其他词性的词，如副词、冠词等。 6.3 标题的结构学术文章的标题主要有三种结构：名词性词组（包括动名词），介词词组，名词词组+介词词组。间或也用一个疑问句作标题（多用在人文社会科学领域），但一般不用陈述句或动词词组作标题。 （1）名词性词组名词性词组由名词及其修饰语构成。名词的修饰语可以是形容词、介词短语，有时也可以是另一个名词。名词修饰名词时，往往可以缩短标题的长度。以下各标题分别由两个名词词组构成。 例2 a.Severe Weather and the Automobile（名词词组） （名词词组） b.Soil Behavior and Critical Soil Mechanics（名词词组） （名词词组） c.High Speed Flow Sensor and Fluid Power Systems Modelling（名词词组） （名词词组） d.Traditional Versus Adult Studies Students： the College（名词词组） （名词词组） Experience（2）介词词组介词词组由介词十名词或名词词组构成。如果整个标题就是一个介词词组的话，一般这个介词是“on”，意思是“对……的研究”。 例3 a.On the Distribution of Sound in a Corridor b.On the Crushing Mechanism of Thin Walled Structures（3）名词／名词词组+介词词组这是标题中用得最多的结构。 例4 a.Fundamentals of Flow Measurement .（名词） （介词词组） b.Scattered Sound and Reverberation on Gity Streets and in Tunnels（名词词组） （介词词组） c.Dietary Supplement and Body Image in Female College Students（名词词组） （名词词组） （介词词组） d.Knowledge of Cardiovascular Disease in University Students（名词） （介词词组） （介词词组） e.Diversity in the Future Work Force（名词） （介词词组） f.Progress on Fuel Cell and Its Materials（名词） （介词词组） g.Damping Capacity of Shape Memory Alloy（名词词组） （介词词组） h.Acoustics of Long Spaces：Theory and Application（名词） （介词词组） （名词词组） i. Investigation of Air Bags Deployment Forces（名词） （介词词组） on Out-of-Position Occupant（介词词组） j. Models of sustaining Human and Natural Development（名词） （介词词组） in an Urban Environment（介词词组） 标题中的介词词组一般用来修饰名词或名词词组，从而限定某研究课题的范围。这种结构与中文的“的”字结构相似，区别是中文标题中修饰语在前，中心词在后。英文正好相反，名词在前，而作为修饰语的介词短语在后。 例5 a.Progress on Fuel Cell and lts Materials燃料电池及其材料进展b.Computer Simulation and Experimental Study On Co1d Shut During Mold Filling铸件充型中冷隔过程计算机模拟及其实验研究c. On the Fatigue Life Prediction of Spot Welded Components点焊汽车构件疲劳寿命预测c.Investigation of Air Bags Deployment Forces on Out-Of-Position Occupant安全气囊对离位乘员作用力的分析与研究（4）其他形式对于值得争议的问题，偶尔可用疑问句作为论文的标题，以点明整个论文讨论的焦点。 例6 a.Do Electromagnetic Fields Affect the Way Plants Grow？ b.Do Specific Ambient Odors Enhance Short Term Memory Function？ c.130 Heterotrophic Protozoa Release Major Quantities Of Dissolved Organic Phosphorous in Lake Water？ 有的标题由两部分组成，用冒号（：）隔开。一般来说，冒号前面一部分是研究的对象、内容或课题，比较笼统，冒号后面具体说明研究重点或研究方法。这种结构可再分为三种模式。 模式1 研究课题：具体内容例7 a.Microelectronic Assembly and Packaging Technology：Barriers and Needs b.Fire Resistant Steels for Construction：Design，Properties and Microchemistry c.Acoustics of Long Spaces Theory and Application d.Impact of Cancer：Coping Process and Quality of Life模式2 研究课题：方法／性质例8 a.Solid Oxide Fuel Cell：A Survey b. Absorbable Implants in Finger Fractures. A Biomechanical and Comparative Study c. The Use of Technology in Higher Education Programs： a National Survey d. Development of New Public Water Supply Well-fields Using Electromagnetic Conductance： Two Case Studies模式3 研究课题：问题焦点a. Aluminum： Is It Hazardous to Your Health？ b. Noise： Good？ Bad？ Maybe Both？ c. Manure： Friend or Foe？ 思考题下面这写论文标题是否合适？如果不合适，请修改。 1. Auditory Perspectives of Different Types of Music 2. Electromagnetic Fields Have Harmful Effects on Humans 3. How to Use Water Resources for Irrigation in Semiarid Land 4. Water Quality Can Be Protected Through the Successful Integration of Research and Education 5. The Single Community Concept： A Model for Adult Environmental Education 6. Physics and Art： Conceptual Linkages Can Be Uncovered 7. Diamond Is Used for Electronic Devices 8. Yellow Fever's Effect on Transportation and Commerce 9. The Nature of Student Science Project Is Compared with Educational Goals for Science 10. A Qualitative / Quantitative Analysis of the Administrative Management Institute at Cornell University 11. The Americans With Disability Act and Its Applicability to the Mentally Ill， Human Immune-Deficiency Virus and Acquired Immune Deficiency Syndrome Populations： A Statistical Analysis参考答案下面这写论文标题是否合适？如果不合适，请修改。 1. Auditory Perspectives of Different Types of Music （合适） 2. Electromagnetic Fields Have Harmful Effects on Humans （不合适） 改为：Harmful Effects of Electromagnetic Fields on Humans 3. How to Use Water Resources for Irrigation in Semiarid Land（不合适） 该为： Using Water Resources for Irrigation in Semiarid Land 4. Water Quality Can Be Protected Through the Successful Integration of Research and Education（ 不合适） 该为： Protecting Water Quality Through the Successful Integration of Research and Education 5. The Single Community Concept： A Model for Adult Environmental Education （合适） 6. Physics and Art： Conceptual Linkages Can Be Uncovered（不合适） 改为： Physics and Art： Uncovering Conceptual Linkages 7. Diamond Is Used for Electronic Devices（不合适） 该为：Use of Diamond for Electric Devices 8. Yellow Fever's Effect on Transportation and Commerce （合适） 9. The Nature of Student Science Project Is Compared with Educational Goals for Science（不合适） 改为： The Nature of Student Science Projects in Comparison to Educational Goals for Science 10. A Qualitative / Quantitative analysis of the Administrative Management Institute at Comell University （合适） 11. The Americans With Disability Act and Its Applicability to the Mentally Ill， Human Immune-Deficiency Virus and Acquired Immune Deficiency Syndrome Populations： A Statistical Analysis （ 不合适） 该为： The Americans With Disability Act and Its Applicability to the Mentally Ill， Human Immune-Deficiency Virus and AIDS Populations： A Statistical Analysis

Annex 3: Agricultural Policy and Food Security in China中国农业政策与食品安全--------------------------------------------------------------------------------IntroductionFood security and the performance of the agricultural sectorAgricultural development strategy, policies and food securityChina's food economy prospectsIssues and challengesConcluding RemarksReferences--------------------------------------------------------------------------------IntroductionChina's effort to produce enough to feed its growing population has long been recognized. It feeds over one-fifth of the world's population with only one-fifteenth of the world's arable land. In recent history, China has either exported food or imported relatively little. China was a net exporter of food, even of grain, in the 1950s. Although China became a net importer of grain in the 1960s, the share of net imports to total domestic consumption was marginal. Net import shares reached approximately three percent in the early reform period (1978-84), then declined to approximately one percent in the following period (1985-90). China has since become a net grain exporter, except in 1995 when it had a record level grain imports of nearly 20 million tons. Net exports between 1992 and 1994 were over 5 million tons annually.While China's grain imports may grow slightly in the coming decades, the nation has developed a strong position as a net exporter of food (both grain and non grain) in value terms by exporting high value-added foodstuff including livestock products and other processed foods during the reform period. Net food exports grew to 2.3 billion US dollars in 1985 and peaked at 6.3 billion dollars in 1993, from a state of balanced trade (in value terms) in 1980 (China Customs Statistics).China's future food security, however, is a subject of growing concern. First, although China's food production has grown over the last several decades, year-to-year fluctuations of food supply and prices are significant. Market stabilization and food price inflation have been among the major targets of government policy since the late 1980s. The Chinese government considers maintaining a comparatively high level of food self-sufficiency, avoiding supply shocks, and stabilizing consumer prices, a matter of national security and stability:Only when the Chinese people are free from food availability and stability of food supply worries can they concentrate on and support the current reform, thus ensuring a sustained, rapid and healthy development of the economy (The State Council, 1996).To this end, the government recently adopted measures to stabilize domestic food supply and stabilize the market - these measures include administrative and economic intervention in food distribution and marketing systems, national and local food reserve schemes, price regulations, international trade, factor markets, and rural infrastructure development.Secondly, food security and access to food are mainly poverty issues. Although national economic growth is strong, it is uneven across regions. Farmer's incomes in the central and eastern regions of China continue to grow more rapidly than those in the west and southwest. Income inequality among regions, between rural and urban areas, and within regions continues to grow (MOA, 1997). In the early 1980s, tremendous progress was made in addressing China's poverty problem, mainly due to the government's rural reform program. However, this progress has slowed down over the past ten years.Finally, China's food supply availability could be a major food security issue in the coming decades if policies were not formulated in the right directions. Worldwide, food production growth rates have outpaced population growth in recent decades, implying increased food availability per capita. Furthermore, the decline of real food and feed grain prices internationally over the same period implies that supply increases have exceeded increased demand. However, the situation differs from country to country.China faces the great challenge of feeding its growing population with declining land, water, and other food production resources, and increasing opportunity cost of labor and domestic food production cost. Food supply availability in China is important not only because it concerns a large proportion of the world's population and consumption, but also because rapid industrialization has led to competition for resources between agricultural and non-agricultural sectors, strong income growth, rapid urbanization, and population growth. All of these stimulate demand for agricultural products.Government officials and scholars have focused food economy and food security concerns on the grain economy because grain (both food and feedgrain) is a major component of China's food supply. Historically, grain fundamentalism, the provision of adequate cereal grain supplies at low stable prices to urban residents, has been an overriding government concern. Recurring food shortages, particularly the famine of the early 1960s, increased the official desire for assured and secure grain supplies. This concern, coupled with rapidly increasing urbanization, domestic infrastructure and transport constraints, domestic grain price spikes in 1994/1995, Brown's 1995 prediction that China will become an importer of massive amounts of grain in the next few decades, the weaknesses of the fiscal system in the provision of public goods (particular agricultural research and extension), has attracted worldwide attention in the past 4 years.A number of recent studies conducted by both domestic and international organizations have led to a consensus that while the increases in China's grain imports will be marginal and the nation will remain at a high level of food self-sufficiency in the coming decades, China's long-term food security is an issue of both national and international significance. The sheer size of China's economy and its rapid growth will make China a crucial influence in the future development of world markets for inputs and outputs of food and agricultural products, agribusiness, and industry. Along with this growth is its gradual progress toward market-orientation and global integration, urbanization, the shift of comparative advantage from agriculture to other sectors, and dietary diversification. Small adjustments to China's food supply and demand, agricultural input demand shifts, and the Chinese government's selection of food security policy will each have large effects on world agricultural trade.This paper evaluates China's food security situation, reviews the performance of the food and agricultural sector, considers the role of food policies, particularly the most recent price and marketing reform policies, in improving the food situation, and identifies key issues related to food security which require further intervention. The next section reviews previous achievements and sources of growth in agricultural production and food security. The third section analyzes current government policies and programmes and their impacts on agricultural production and food security. The fourth section predicts the shape of China's food economy over the next three decades; while the fifth section discusses the major challenges and constraints to agricultural production and food security. Concrete measures and options towards sustainable agricultural growth and food production are suggested in the final section.Food security and the performance of the agricultural sector--------------------------------------------------------------------------------Food security: an overviewSummary of China's approaches to improved food securityOther issuesChanging role of agriculture in the economyAgricultural production growth--------------------------------------------------------------------------------Food security: an overviewChina's ability to feed over one-fifth of the world's population with only seven percent of the world's arable land is widely acclaimed. China, with more than 1.23 billion people in 1997, is the world's most populous nation. Its experience demonstrates the importance of technological development, institutional change, improved incentives, and rural development among other policies in improving food security with limited natural resources.Availability of foodChina's per capita food availability and consumption have increased over the last several decades. Average per capita food availability has grown from less than 1700 kcal in 1960 to 2570 kcal per day in 1995 (Table 1)[19]. Increased domestic production is almost solely responsible for increased food availability. Protein intake and fat consumption per capita per day increased over the same period, from 42 grams to 70 grams, and 17 grams to 45 grams, respectively. Both figures exceed average nutrient availability in countries with comparable per capita GNP levels.Nutritional composition changes of Chinese diets are consistent with growing income (Table 1). Nutrient sources are a powerful indicator of the population's economic wellbeing. In low income countries, the average diet includes a high percentage of nutrients from crops, while a typical developed country diet includes a relatively high percentage of nutrients from animal sources. In China, traditional diets were typically based on cereals, vegetables, and small quantities of meat and fish. Consumption of relatively expensive non-cereal food items, particularly livestock products and fish, have increased with rapid increases in per capita income, urbanization, and market expansion (Huang and Bouis, 1996).Aggregate household food securityAggregate household food security has improved significantly. According to the FAO's WFS (1996), Chinese household food security, as measured by the aggregate household food security index (AHFSI) and the level of food inadequacy, follow overall national averages. The AHFSI increased from a low level of 70 percent in 1969-71 to a relatively high level of nearly 80 percent in 1990-92, while food inadequacy declined from slightly over 14 percent to approximately 3 percent in the same period.Table 1. Nutrient availabilityYearEnergy(kcal)Protein(grams)Fat(grams)Crop ProductsAnimal ProductsEnergy(%)Protein(%)Fat(%)Energy(%)Protein(%)Fat(%)196016764217979376372419702087532396936747331980247064329490606104019902505683791865591445199525707045888151121949Table 2. Per capita daily nutrient intake by income group in sample provinces, 1990.Income groupSichuanNingxiaHebeiZhejiangGuangdongBeijingEnergy intake (kcal)Average233524022227246024252309Poorest 10%18891819197019712129196010% - 25%20682142209322172174185525% - 50%22712319220123142191209150% - 75%24852480225625592583237175% - 90%260626422284271125322605Richest 10%285230742559298327972972Protein intake (g)Average59.668.569.163.960.769.1Poorest 10%48.154.959.451.051.957.910% - 25%52.564.664.757.053.055.025% - 50%55.465.467.959.658.462.050% - 75%61.168.770.265.664.570.375% - 90%66.672.571.470.764.779.2Richest 10%73.684.580.879.271.890.5Fat intake (g)Average36.033.734.033.139.145.5Poorest 10%25.521.527.420.228.935.510% - 25%27.725.629.226.432.735.425% - 50%31.331.131.930.336.841.150% - 75%37.035.635.035.142.548.575% - 90%43.441.037.139.842.052.6Richest 10%57.048.946.147.650.663.9Annual per capita income (yuan)Average55864365899110271270Poorest 10%25123020429943348810% - 25%34732134950862470525% - 50%443457499739809101250% - 75%57968669210581075134675% - 90%756975948145714331748Richest 10%111513951453216320332633Household food security by income groupTables 2, 3, and 4 show household nutrient intake and source by income group based on a food and nutrition survey conducted by the Chinese Academy of Preventative Medicine (CAPM) and the State Statistical Bureau (SSB) in 1990,. Tables 5 and 6 show the physical development of children and equity as well as poverty in the rural China based on a food consumption and expenditure survey conducted by the SSB for the years 1978- 95.Nutrient intake varies greatly across income groups, although average per capita energy intake in all sample provinces topped 2200 kcal (Table 2). Daily energy intake of the 25% of the population with annual per capita income less than 500- 700 yuan (level varies by province) was below 2200 kcal. Energy intake of the poorest 10 percent was only 82 percent of the sample average. Protein and fat intakes decline as income falls in a similar pattern.Table 3. Sources of energy by income group in China's sample provinces, 1990.