新加坡21世纪新镇规划模式研究——以榜鹅新镇为例

自20世纪60年代以来,新加坡建屋发展局就借鉴西方居住区理论在亚洲创造性地拟定了一套新镇发展模式并开发了23个新镇。经历了"邻里组团中心"、"棋盘式"模式之后,新加坡以榜鹅新镇为试验点开创"21世纪新镇"模式。榜鹅21世纪新镇在继承"田园城市"思想的基础上,汲取新城市主义的TOD模式和景观都市主义理念,以分层TOD为构架建设景观基础设施,在社区层面全面实践生态策略与技术并普及群众环境意识。学习总结榜鹅21世纪新镇模式的先进之处对我国新城规划具有一定的借鉴意义。     

社会化服务对农户农药减量行为的影响——基于服务专业化维度的考察

[目的]在社会化服务体系建设不断推进的背景下,农户并非是可自我执行农药减量化的行为主体。分析社会化服务对农户采纳农药减量行为的影响,旨在发掘出以服务规模经营方式促进农户采纳农药减量行为的可行性策略。[方法]文章基于甘肃省802户农户调研数据,利用倾向得分匹配法构建反事实框架,剖析不同专业化服务对农户农药减量行为的影响,最后运用分位数回归模型分析农户农药减量不同行为水平下社会化服务影响效应的动态变化。[结果]（1）农业社会化服务能够显著促进农户采纳农药减量行为。（2）讨论内生性后,社会化服务领域下更细化的专业化服务如技术培训、施药外包、农产品销售、产品质量认证等服务对农户农药减量行为具有显著正向影响,而农资供应服务的影响不显著。（3）技术培训、施药外包、产品质量认证等服务对农户农药减量行为高水平组的促进效果最强,对中等水平组的促进效果次之,对低水平组的促进效果最弱,而农产品销售服务的促进作用从中等水平组到高水平组呈现减弱趋势。（4）党员身份、信息来源对农户农药减量行为具有显著正向影响,种粮目的、风险感知对农户农药减量行为具有显著负向影响。[结论]政府对不同类型社会化服务的政策支持应有所差...     

社会经济因素对农户种植决策行为的影响——基于主体模型的像元尺度模拟

[目的]保证粮食安全关乎国计民生和社会稳定。合理调控种植结构,优化粮食配比和产量,对于稳定粮食安全有着举足轻重的作用。目前,以大豆为主的油料作物多依赖进口,严重威胁我国的粮食安全,为了优化种植结构,提升油料作物自给率,对农户种植决策行为的研究十分必要,具有科学价值和政策意义。[方法]文章选取黑龙江省松嫩平原粮食主产区的主粮种植结构为研究对象,通过农户问卷调查并结合社会经济统计数据以及作物空间分布数据,采用基于主体模型（Agent-based Model,简称ABM模型）模拟了2016—2020年农户作物种植（大豆、水稻、玉米）的决策行为以及作物空间分布格局。[结果]ABM模型模拟的平均总体精度为63%,结果显示种植决策行为与社会规范因素较为相关,例如：农户所处周边社会环境中大多数人种植水稻,该农户有较高的概率选择种植水稻;经济因素也是重要的影响因素,例如：水稻种植收益高则更多人种水稻。根据ABM模型的情景分析结果显示,农户受周围农户种植决策影响程度越高,越倾向于选择周围农户的种植结构;而当大豆补贴金额变化时,农户更倾向于选择种植收入较高的种植结构。[结论]该研究构建的基于农户决策行为的...     

仓储小麦品质变化监控检测研究现状及进展

小麦仓储过程中品质会发生一系列的变化,保持其品质新鲜,控制和减缓粮食品质劣变,不用或少用化学熏蒸药剂,为消费者提供绿色放心粮食,是中国粮食仓储行业目前面临的一项紧迫任务.文章对气调储粮、温湿调控、智能监控、害虫检测、菌群检测等储粮检测方法方式进行了系统阐述分析,综述了仓储小麦品质劣变监控检测的研究进展,并结合当前存在的...     

The impact of deal‐proneness on WTP estimates in incentive‐aligned value elicitation methods

Even after controlling for hypothetical biases, some incentive‐aligned value elicitation methods still produce different willingness‐to‐pay (WTP) estimates. In this study, we compare WTP estimates from three incentive‐aligned value elicitation methods: real choice experiment (RCE), real double‐bounded dichotomous contingent valuation (RCVM), and Becker–DeGroot–Marschak auction (BDM). We find that participants’ aggressiveness in obtaining low prices (i.e., “deal‐proneness”) influences WTP estimates in the BDM auction, but not those elicited from the RCE and RCVM. The participants with higher levels of deal‐proneness tend to submit lower bids in the BDM auction. The discrepancies in WTP estimates between different incentive‐aligned procedures are narrower for participants with lower levels of deal‐proneness. Our results indicate that the bids in BDM auctions may be understated and the auction mechanism may induce the “gambling behavior” of people who are deal‐prone. That is, whether the BDM auction is truly incentive‐aligned is again called into question. We also discuss the practical implications for food retailers.     

Safe food,green food,good food: Chinese Community Supported Agriculture and the rising middle class

The growth of China's middle class is driving an expansion of interest in ‘green’ and sustainable food, food that is perceived to be healthy, safe and environmentally friendly. Self-consciously ‘sustainable’ agriculture is a new phenomenon in China, but it has emerged from, and builds upon, an agrarian history that is markedly different from that of the West. In this paper, we address the relationship between the Chinese middle class, an overwhelmingly urban group, and Chinese sustainable agriculture, a largely urban-oriented enterprise, from the perspective of our work in establishing and operating Beijing's first Community Supported Agriculture (CSA) farm. We discuss the farm's environmental and institutional sustainability, situating its development within the larger context of contemporary Chinese agriculture, and we examine the potential for future success with CSA models in China based on evidence from this case.     

哈东沿江湿地自然保护区野生种子植物组成及区系划分

为掌握黑龙江哈东沿江湿地自然保护区野生种子植物资源现状,本研究于2018-2020年,采用样线法,在该保护区内对野生种子植物组成进行实地调查,并对科、属及种的区系进行分析.结果显示,该保护区内共发现野生种子植物53科162属265种(包括2亚种及3变种),均为被子植物.以菊科(Compositae)、禾本科(Grami...     

甘肃省中药材产业发展现状及对策研究

与全国其他地区相比,甘肃省在中药材资源、栽培面积及产量方面具有优势。省内相关地区已将中药材作为当地重要支柱产业,组织大规模的开发生产。该文从甘肃中药材产业的现状入手,在分析甘肃省中药材产业发展问题的基础上,提出了甘肃省发展中药材产业的对策建议,为甘肃的优势产业发展提出理论依据。     

基于 GIS与指数和法的百色市烤烟种植区气候适宜性评价

气候条件是决定烟叶质量和风格的重要因素,百色烟区是广西第一大优质烤烟产区,该研究通过分析百色市历年气象数据和烤烟品质指标,选取影响百色烤烟品质的气候因子,利用主成分分析法计算不同气候因子的权重;结合百色优质烤烟生长对气候条件的要求,利用 AGIS软件的空间分析功能与指数 和评价法,分析单个气候因子分布情况,并将其量化分级;综合单一气候r因c子的量化等级和权重,得出百色市烤烟种植区气候适宜性评价指数;根据评价指数将百色市分为烤烟种植适宜区、较适宜区、不适宜区 3个适宜性分区,这一结果显示出不同适宜性分区的潜在分布,从气候适宜性角度来看,百色烤烟种植面积还有很大扩展潜力,烤烟种植向适宜区和最适宜区转移,提供了理论依据。     

Locational effects and the cost of corporate bonds: the role of information

The public yield spreads of bonds vary widely between Chinese provinces/municipalities, with the average for the highest province double that of the lowest one. Although we find that these patterns are mainly attributable to economic and legal conditions, locational effects like geographic distance and public firm credit ratings also appear to be contributory. We show that these effects are induced by different regional informational environments and are robust to controlling for potential endogenous location choices.