消费型大都市蔬菜消费补贴效率研究——基于上海的实证分析

随着人们更加注重健康生活,蔬菜已经成为居民健康饮食必不可少的一部分,而对蔬菜给予补贴对保障蔬菜供给、稳定价格、保护农民利益、促进食品安全及发展现代农业等方面具有重要意义。因此本文利用2011-2015年上海市7个区蔬菜补贴数据,运用DEA和Malmquist指数测算发现：蔬菜补贴政策效率无效是由技术效率和规模效率无效造成的,其中规模效率无效是主要的原因;并且各区补贴规模与生产规模存在一定的不匹配现象;蔬菜补贴的Malmquist生产率年均降低13.5%,这主要因为技术水平的落后和规模补贴不合理造成的。据此提出各个地区应根据蔬菜产业发展实际情况,合理调整补贴规模等建议。     

我国蔬菜价格保险政策市场效应分析——以上海市为例

蔬菜价格保险是政府宏观调控农产品市场、促进市场价格平稳运行和深化农业供给侧结构性改革的重要手段之一,深入探究我国蔬菜价格保险政策的市场效应有着重要现实意义.通过构建全国31个大中城市2001-2017年的面板数据,运用合成控制法(SCM)实证分析上海市蔬菜价格保险政策的市场效应.研究结果表明:蔬菜价格保险政策整体上对 ...     

Magnetic properties of the urban soils in Shanghai and their environmental implications

To study the feasibility of using magnetic techniques for monitoring soil pollution in Shanghai, magnetic properties and heavy metals in the topsoils in an urban site (Songnan Town) and a less-urbanized agricultural site (Luojing Town) in Baoshan District, Shanghai, were studied. Compared with the background, magnetic signals of the urban topsoils are extremely enhanced with magnetic susceptibility (χ_lf) from 127.3–1959 × 10^− 8 m³ kg^− 1; while those of the agricultural topsoils are only slightly increased. However, both the urban and agricultural topsoils contain few pedogenic SP grains, as indicated by their low χ_fd% (< 3.6%). Ratios of χ_arm/SIRM, χ_arm/χ_lf and SIRM/χ_lf indicate that the grain size of magnetic minerals in the urban topsoils is significantly coarser than that in the background and the agricultural topsoils. Furthermore, the urban topsoils show low coercivity and magnetic soft behaviors, as indicated by higher SOFT%, lower HARD%, higher IRM_300 mT/SIRM (close to 1) and lower IRM_− 200 mT/SIRM (close to − 1). It suggests that the urban topsoils have received some coarse ferrimagnetic particles. Heavy metals are highly enriched in the magnetic fractions of the topsoils. Geochemical properties of the magnetic fraction of the urban topsoils are significantly different from those of the agricultural topsoils, further indicating that the extra magnetic minerals accumulated in the urban topsoils are neither inherited from soil parent materials nor from pedogenic processes, but originate from anthropogenic activities. The significant correlations between heavy metals and χ_lf, χ_arm, SIRM, SOFT and HIRM of the topsoils in the district indicate that the magnetic techniques can be used for monitoring soil pollution in Shanghai. The soils with χ_lf from 39–50 × 10^− 8 m³ kg^− 1 in the district are tentatively defined as “slightly polluted soils”; those with χ_lf > 50 × 10^− 8 m³ kg^− 1 are defined as “polluted soils”.     

上海市郊林带的防风效应分析

用夏季台风影响期间上海市东南沿海南汇海塘边林带防风观测资料和冬季冷空气影响时北面嘉定浏岛林带防风观测资料分析上海市郊林带的防风效应。结果表明：无论是夏季台风还是冬季冷空气影响时，林带的防风效应是非常明显的。台风影响期间，离林带越近，减风效应越大，随高度增加，减风效果减小；而远离林带处的减风率较小，随高度升高，减风效果增大；而且林带的减风效应还与风速有关，风速越小减风效果越明显。冬季由于受两条交叉林带的影响，两个测点的防风效应基本一致。试验结果可为上海市郊林带布局提供参考。     

土壤消解方法研究及对上海浦东环境汞背景值初步调查

利用欧洲标准样作控制,对比研究了土壤总Hg测定的3种消解方法,并对浦东垃圾焚烧发电厂周围土壤总Hg的背景值进行了初步研究,结果发现浦东土壤Hg背景值达到192.68 ng/g,明显高于其它城市,这与上海的工业历史、农业施肥习惯有关,值得注意的是浦东地区土壤中的气态Hg(一个样品除外)含量都很高。     

2007-2017年夏冬季上海市内外圈层土地覆盖与地表温度的定量关系

[目的]探究超大型城市地表温度对不同土地利用类型的响应特征,为城市建设和规划设计提供科学参考.[方法]以上海市为例,运用2007,2013,2017年夏冬季共6期Landsat系列多光谱及热红外影像数据,解译土地利用类型并反演地表温度,基于900m×900m网格分析了夏季和冬季上海市外环内外土地利用类型对地表温度影响特...     

上海市水力侵蚀现状与水土保持措施分析

为研究上海市水土流失及措施现状,以第一次全国水利普查水土保持情况普查结果为基础,结合上海市基本情况,分析上海市水力侵蚀现状和水土保持措施情况。结果表明,上海市水土流失面积超过了200km^2,水土流失以河道两岸和湖泊沿岸的坍塌淤浅为主要特征,建设项目施工造成的人为水土流失也是上海市水土流失的一个重要方面。上海市中心城区水土保持措施较完善,但郊区部分河道还没有采取有效护坡措施,基本处于自然状态,很容易发生水土流失;因此,河道边坡和湖泊岸线的护岸整治、海岸滩涂的保滩促淤治理是上海市水土保持工作的重点,同时还应加强建设项目的监管和水土保持监测,以防止人为水土流失。     

上海地区国外树种引种调查分析

为了给上海辰山植物园5大洲植物引种项目提供必须的树种材料,对上海20年来国外树种的引种情况进行调查分析,对其科属分布、种源地情况、生态位、园林用途进行研究。结果表明：（1）槭树科的木本植物引种数量最多,其次是豆科和桃金娘科;（2）美洲区系植物引种最多,达71种,其次为欧洲区系31种;（3）生态位分析结果为乔木数量最多,达到108种,灌木67种;（4）引种植物中落叶树种108种,多于常绿树种的69种;（5）引种方向主要是耐盐碱、耐水湿或有一定耐寒、耐热能力的树种;（6）引种树种在园林绿化中主要用作行道树、园景树、庭园树、水土保持林、花坛、花境和隔离带等。     

上海市市场猪肉溯源性调查研究

近年来由于我国肉类食品安全问题严重,为了保障猪肉食品的公共安全,政府监管猪肉的安全生产和食品消费者的知情权,我国建立了猪肉质量安全可追溯系统。我国的猪肉消费主要以生鲜肉为主,冷却猪肉生产起步较晚,消费量的市场份额不到10%。通过市场调查的方式对本市杨浦区的大中小型超市、冷鲜肉专柜和菜市场等地的生鲜肉的溯源性现状进行了调研。在一共60份采样中,可溯源样品44份,占总数的73%,其中标有溯源码的样品只有10份,且全部来自大型超市,占总数的16.7%。由此可见,目前国内市场的猪肉溯源性现状还是不容乐观。     

Analysis of the Environmental Design of the Urban Sunken Square: A Case Study of Shanghai Wujiaochang Sunken Square

Under the background of stock planning,fine planning promotes intensive and efficient utilization to become an important measure of urban space utilization.The three-dimensional development of urban public space promotes the emergence and gradual growth of urban sunken square.However,there are many problems in the design of urban sunken square.In order to have a clear understanding of the current situation between the sunken square and the surrounding environment in the domestic mega city,the Shanghai Wujiaochang Sunken Square was selected for field investigation and questionnaire survey to understand the main problems and advantages and disadvantages in this case.The common problems were summarized and the disadvantages of the lack of integration between the sunken square and the surrounding environment were obtained and the role of integration of the two was clarified.It is expected that the design points of sunken square and surrounding environment integration can provide guidance for the follow-up design.