粮食直接补贴对不同经营规模农户小麦生产率的影响——基于全国农村固定观察点农户数据

本文使用2003~2014年全国农村固定观察点河南省样本农户数据所组成的面板数据,选用EBM模型和GML指数分析了2009~2014年河南省小麦生产技术效率和小麦全要素生产率,然后将小麦全要素生产率进行了要素分解,使用相关工具变量和2SLS方法分析了粮食直接补贴对不同经营规模农户小麦生产率的影响。本文研究发现:2009~2014年,河南省小麦生产存在规模效应,而小麦全要素生产率进一步增长,要素投入增加是其小麦全要素生产率增长的主要原因;粮食直接补贴对农户的小麦生产技术效率具有积极作用,而对经营规模为6亩以上农户的小麦全要素生产率作用不大;从粮食直接补贴对小麦全要素生产率的各贡献因素的影响看,粮食直接补贴能促进经营规模为0~6亩农户的人力资本增长率和经营规模为6亩以上农户的要素投入增长率,但是,这些影响不足以促进小麦全要素生产率的提高。     

农地流转对农户生产率的影响——基于DEA方法的实证分析

本文运用DEA方法测算了北京、上海和广东三省份农地流转对农户生产率的影响,并进一步分析了不同类型农户出现生产率差异的内在原因。实证研究发现:样本农户的平均生产率只有0.28,仍然处于较低的水平;农地流转会降低农业的技术效率,但是会提高农业的规模效率,且规模效率的正效应大于技术效率的负效应,因而提高了农业生产率;94.5%的农户都处于规模报酬递增阶段,因此,土地流转是提高农业生产率的有效途径;农地流转会显著增加劳动生产率,但是会降低土地生产率;转出土地的农户在生产时更多地使用劳动和资本,而转入土地的农户则更多地使用土地和资本。     

财税政策、工农业分工与农业生产率——理论分析与经验证据

本文基于动态分工演进,以自给自足的自然经济为起点,将秩序服务和财税政策纳入一个理论框架,结合超边际决策分析和一般均衡分析,考察在此过程中各个经济人的最优决策在市场上相互作用而内生的各种变化,揭示了财税政策作用于工农业分工和农业生产率的内在机制。然后,使用中国改革开放以来的数据对相关结论进行实证检验。模型分析表明,政府财税政策的实施在促进工农业分工水平提高的情况下,会扩大粮食生产的迂回化经济程度,进而推动粮食部门的农地生产率提升。就长期而言,单位面积的财政支农支出对农地生产率的提高有显著正向影响,在其他农业生产要素既定情况下,单位面积的财政支农支出每增加1%,农地生产率增加3.23%;从短期来看,单位面积财政支农支出对农地生产率的作用较弱,但在反向修正机制的作用下,最终会达到有效提高农地生产率的长期稳定均衡。另外,财政支农支出的增加促进了分工水平的提高,而分工水平的提高又推动了农业生产率的提升。     

农地流转影响粮食种植结构分析

本文基于2003—2012农业部全国农村固定观察点微观调查,应用统计描述性分析和固定效应面板模型,分析了农户农地流转行为带来的粮食种植结构调整效应。研究发现,2003—2012年全国层面粮食种植比例趋于下降。粮食内部结构也发生调整,水稻种植比例下降,小麦稳中微降,玉米的种植比例快速提升。描述性分析显示,转入户的粮食种植比例高于非流转户,而非流转户又高于转出户。固定效应面板拟合结果也证实,农地流转对粮食种植结构有显著的影响,农户的土地转入(转出)行为能够有效提升(降低)粮食种植比例。但农地流转对三大主粮种植结构的影响出现分化,转入(出)行为能显著增加(减少)农户的水稻种植比例,但农户农地流转行为对小麦和玉米的种植没有影响。     

农地细碎化对农户农地流转决策的影响研究

研究目的:分析农地细碎化对农户农地流转决策的影响。研究方法:成本—收益理论,排序概率选择模型。研究结果:(1)农地细碎化增加了农业生产成本,降低单位面积农业生产收益,对农户农地最优经营规模产生负向影响;(2)农地细碎化对农户转入意愿产生负向影响,使农地流转市场的需求量减少;(3)农地细碎化对农户转出意愿虽有一定的正向影响,在一定程度上使农地流转市场的供给量增加,但农户转出意愿主要受非农就业影响。研究结论:为活跃农地流转市场,应采取农地整治等措施降低细碎化程度,鼓励新型农业经营组织转入农地,形成适度规模经营的农业生产格局,增加农地流转市场的需求量;此外,应深化城市经济社会体制改革,提供更多更好的非农就业岗位,以吸引农民市民化,使更多的农民愿意转出农地,增加农地流转市场的供给量。     

农业支持保护补贴促进规模农户种粮了吗?——基于全国农村固定观察点调查数据的分析

本文利用最新的全国农村固定观察点调查2016年和2017年两期数据,考察了农业支持保护补贴对规模农户种粮的影响,结果显示:第一,无论是纯粮食种植户还是粮食为主种植户,农业支持保护补贴皆显著扩大了规模农户的粮食播种面积;第二,农业支持保护补贴主要是通过促进规模农户转入更多土地来扩大粮食生产,对农户的种植结构没有显著影响。这表明,农业补贴改革取得了一定的效果,同时,加大对农地经营者的补贴支持可成为解决当前农地流转不畅、促进规模经营、保障粮食安全的一个重要手段。     

农地流转提升了粮食生产技术效率吗——来自农户的视角

为检验农地流转是否提升了粮食生产的技术效率,本文基于粮食主产区346个农户的调查数据,采用超越对数形式的随机前沿生产函数(SFA)测度农户粮食生产技术效率,先对有/无农地流转两类农户的技术效率进行统计分析,后基于回归结果测算劳动力、土地、农资、农具等投入要素的产出弹性,最后采用Tobit模型检验影响粮食生产技术效率的主要因素。研究表明,土地流转提高了粮食生产技术效率,从具体投入要素的产出弹性来说,土地流转提高了劳动力、农具和农资等要素的产出率,但降低了土地要素的产出率;从粮食生产技术效率的影响因素来说,无农地流转行为、劳动力受教育水平、家庭总收入和农业信息可得性对农户的粮食生产技术效率有显著正向影响;非农收入占比、农地离城镇平均距离则有显著的负向影响。最后提出,促进农地规模化流转、降低土地地块层面的细碎化水平、增加农业劳动力人力资本投资、提高农业生产机械化率、拓宽农户信息获取渠道和完善农村公共产品供给体系是当前提高粮食生产技术效率的有效措施。     

不同经营规模农地效益的比较及其演变趋势分析

中国是一个农地资源人均拥有相对稀缺的国家 ,由于多数人的谋生仍是以农为主 ,所以 ,作为农地经营的主体———农户 ,其经营规模明显偏小 ,从而使得农地利用效率十分低下 ,农业大规模性商品性生产目标越来越难以实现。特别是在面对ＷＴＯ ,农产品生产竞争将会日益激烈 ,而中国这种分散的 ,以小规模为主的农户经营形式所形成的竞争力明显不足 ,所以 ,有必要正确引导农户在经营农业时 ,向农地适度规模经营转化。但究竟多大的“度”有利于提高农地的利用效率 ?本文根据 1986— 1999年浙江省农村固定观察点① 10个村跟踪观察户资料 ,对此做出分…     

2004年农户农产品生产意向调查分析

农村固定观察点办公室在2003年12月进行了2004年农户的农产品生产意向专题调查,涉及全国23个省(市、区)观察点村近万个农户,收回问卷9100份,分析结果如下。 一、粮食播种面积基本稳定,大豆、棉花播种面积继续增加     

脱钩收入补贴对小麦生产率有影响吗?——基于农户的微观证据

脱钩收入补贴对粮食生产是否会产生影响,是国内外学术界长期争论的问题之一。本文使用2003~2014年全国农村固定观察点的微观数据,通过实证分析,试图回答脱钩收入补贴是否会影响小麦生产率。为使研究更细致、更严谨,本文选用EBM模型和GML指数来分析河南省小麦生产率的变化,使用较前沿的IVQR模型进行回归估计,并利用相关工具变量和2SLS模型对估计结果进行稳健性检验。研究发现:2009~2014年,脱钩收入补贴对小麦生产技术效率具有积极作用,而对小麦全要素生产率作用不大;受资金约束,小麦全要素生产率较低的农户无法扩大小麦生产规模。此外,本文较有意义的发现是,脱钩收入补贴主要通过改进小麦生产技术影响小麦生产率,而非影响小麦生产的投入产出比。这意味着,中国的脱钩收入补贴不仅符合WTO规则的要求,而且对提高农民收入、促进小麦生产技术进步具有重要意义。     

Produce Retail Price Volatility and Perceptions in the Canadian Market: Nutrition Security Variances

Nutrition security has been studied but rarely in the context of a developed economy. Furthermore, few studies have looked at how fluctuating produce process may influence nutrition security and how consumers cope with abrupt macro-economic changes. Between 2014 and 2015, Canadian consumers saw produce prices jump by more than 25% in a year in some cases. This exploratory survey looks at socioeconomic factors and evaluates how price increases influence produce consumption and substitution. A total of 1007 respondents participated in a cross national survey over a two-week period. Results show that lower income households are more vulnerable than higher income respondents. Results also explore a few more behavioral factors such as where produce shopping occurs and how market data is gathered before purchases. Respondents who consult flyers and use apps are more likely to behave rationally and cope with changing prices. Some limitations are presented. And finally, future research thrusts related to produce price fluctuations and nutrition security are suggested.     

饲料中镉含量的测量不确定度评定

分析石墨炉原子吸收光谱法测定饲料中镉含量不确定度各个分量,对其测量不确定度进行合理评定,结果表明:饲料样品中镉含量为0.052 mg/kg时,其扩展不确定度为0.0035 mg/kg(k=2),校准过程和测试过程随机效应是引入不确定度的主要原因。     

面粉中含砂量测定的不确定度评定

本文依据《粮油检验粉类粮食含砂量测定》对面粉中含砂量进行测量,并对其测量结果进行不确定度分析,探究影响测量过程中不确定度分量来源并进行评定。分析得出,扩展不确定度为0.0004%,面粉中含砂量测定结果为0.017%±0.0004%(k=2)。     

中国水稻生产效率的变动分析

一、引言中国是世界最大的稻谷生产国 ,水稻是中国最主要的粮食作物。我国加入WTO后 ,在市场经济的调节下 ,稻谷生产与贸易受国际市场和价格的影响越来越大 ,因而如何保护我国的农业 ,提高我国水稻的国际竞争力 ,促进我国农产品的生产和贸易 ,是摆在我们面前的一件重要事情。而生产效率的提高有助于提高我国水稻的国际竞争力 ,所以 ,研究水稻的生产效率很有意义和价值。生产效率是指产出量与全部投入之比 ,表明产出量的变动与全部投入量变动的关系 ,以衡量生产率的变化对经济增长的作用。生产效率一般是指生产系统的总要素生产率 (TotalFa…     

食品中金黄色葡萄球菌定量检测的不确定度评定

为提高食品中金黄色葡萄球菌定量检测结果的准确性,本文对测量不确定度进行分析和评定.按照《食品安全国家标准食品微生物学检验金黄色葡萄球菌检验》(GB 4789.10—2016)第二法金黄色葡萄球菌平板计数法对人工染菌的乳粉样品进行检测,按照《测量不确定度评定与表示》(JJF 1059.1—2012)分析不确定度来源、评定...     

分光光度法测定食品中亚硝酸盐不确定度评估

本文根据《测量不确定度评定与表示》(JJF 1059.1—2012)和《食品安全国家标准食品中亚硝酸盐与硝酸盐的测定》(GB 5009.33—2016),利用分光光度法对食品中亚硝酸盐的含量进行测定,建立数学模型对亚硝酸盐含量测定的不确定度来源分量进行计算、分析,食品中亚硝酸盐的测定结果可以表示为X=(11.2±0.70)mg·kg^-1,k=2,为评价试验测量结果的真确性提供科学依据。     

重庆缙云山旅游竞争力提升研究

缙云山作为国家级重点风景名胜区,在自然资源、生态、区位和宗教旅游方面具有一定的旅游竞争优势,但如何有效利用这些优势资源提高景区的竞争力仍是其面临的重要问题。通过分析缙云山的旅游竞争力基本要素,指出其目前存在的旅游产品单一、景区客源市场小等问题。提出改变旅游资源开发方向,完善解说系统,培养专业人才,加强管理等提升缙云山旅游竞争力的相关措施。     

明代华北农业发展的推动因素分析——生产要素角度的描述与估计

本文以明代时期的北直隶、山东、河南为例,从生产要素的角度分析明代华北农业发展的推动因素.一是人口的增长、迁移和耕地面积的增加.二是农田水利,除了治理河流,井灌得到了广泛采用.三是农业技术有所进步.本文还尝试用生产函数模型,分别对中性、劳动增强型和土地增强型的技术进步率进行估计,结苯表明,明代华北农业的增长方式主要依赖于劳动和耕地的增加.在资源约束日益加剧的今天,要进一步重视技术进步在推动农业发展中的作用,同时在技术选择和创新中还特别需要注意与各地的资源禀赋条件相适应.     

Assessment of implementation of protection of mineral deposits in spatial planning in Poland

A complex of raw materials available in a given commune shapes its functional − spatial structure and affects local economic development. The use of the resource base of minerals depends largely on the management of the space and respecting the zoning restrictions connected with protection of mineral deposits. The urgent need to protect them is due to their non-renewable nature and progressive development of the land. Preserving access to deposits is essential to ensure future mineral supply necessary for the economic development. This article presents the results of the assessment of implementation of rules of protection of mineral deposits in spatial planning at the level of territorial units in Poland.The study has been conducted in twenty-three communes of the Lesser Poland voivodeship, for thirty-one unexploited mineral deposits designated for protection in the Spatial Development Plan of the Lesser Poland (Małopolskie) Voivodeship of 2003. In the study of conflict with development of the selected mineral deposits with the environment, factors related to land use, forms of nature protection, water conservation and planned land development have been evaluated. The assessment has taken into account the importance of individual factors of conflict by giving them weights by means of pairwise comparison method. Five classes of conflict of the deposit management have been proposed: non-conflicting deposit, small conflict, medium conflict, major conflict and very big conflict. Almost equal numbers of deposits (9) belong to the class characterized by a of medium, small and large conflicts. Road and technical projects as well as expected significant impact of exploitation on the environment restrain exploitation. The impact is related to the necessity of use of explosives during the exploitation and by the cumulative effect of the mining activity already existing nearby. Analysis of the planning documents of the communes has shown both inadequate protection of mineral resources, including designation of areas of deposits for single-family housing, and a few examples of properly maintained spatial planning in the field of protection of mineral deposits. Information obtained from the environmental survey has been supplemented by assessment of the social aspect. In nine communes it has been determined that the areas of mineral deposits are not subject to spatial conflicts but in seven communes there is opposite situation. The most important benefits from the mineral exploitation which has been indicated in the studied documents included: jobs, access to construction materials and development of the commune.Present work allowed to define the areas and the scale of conflicts induced by development of mineral deposits and to propose measures for rational management of mineral resources. Recognition of the existing and potential conflicts can help to make the right decisions concerning development of the area and minimising impacts of exploitation of the mineral deposits.     

Evaluation of forestland use in mining operation activities in Turkey in terms of sustainable natural resources

Mining has been necessary for human activities and is conducted in line with this need. The location of mines must sometimes be where land use overlaps with other activities because the location of the mined substance cannot be changed. In Turkey, forestland are the most common of these overlapping areas. Therefore, mining has frequently occurred on forestland in Turkey—and worldwide. After the mining operation activities are conducted, the forestland are rehabilitated and returned to the forest administration. The examination of used and returned areas provides an opportunity to create an optimal situation between “mining for sustainable development” and “protection of forestland.”Accordingly, several questions, such as mining production amounts, degrees of social and economic development of the cities in which enterprises are conducting mining, the quantity of the areas they used for mining activities in forestland, the areas which were returned to the forest administration, operating license areas and operation permit areas, and the life of mining operation, were asked to the mining enterprises in Turkey through the “Survey Monkey” program in 2018. Thus, according to mineral groups, different land use rates were compared with the operating license areas, and the land uses for each mineral group were analyzed by considering the operation activity periods. The results indicate that the sustainability of the use of forestry in mining activities in Turkey has changed in a positive direction, particularly because of changes in mining and environmental legislation in Turkey over the last decade.