自然灾害对中国粮食产量影响的实证分析——以稻谷为例

中国稻谷总产量年际变化主要是由播种面积变化和单产变化决定的,其中,单产变化是主要的,其影响程度接近60%。而稻谷单产变化又是由技术因素、社会因素和自然因素决定的,其中又以自然因素为主,其影响程度占48%～56%。实证分析表明,稻谷单产变化中,自然灾害影响产量与其他灾害成灾率的关联度最大,然后依次为水灾受灾未成灾率、其他灾害受灾未成灾率、水灾成灾率、旱灾成灾率和旱灾受灾未成灾率。因此,要稳定发展中国的粮食生产,必须重视农业防灾、减灾能力建设。     

农业常用统计指标介绍（中）

农业常用统计指标介绍（中）９、农业受灾面积和成灾面积受灾面积是指年内因遭受旱灾、水灾、风雹灾、霜冻、病虫害，以及其他自然灾害，使农作物的产量较正常年景产量减产一成以上的农作物播种面积。受灾面积不得重复计算，在同一块土地上如先后遭受几种或几次灾害，只按...     

我国玉米主产省自然灾害灾情分析

[目的]我国是一个多灾多难的农业大国,自然灾害给玉米生产带来重大损失,全面梳理我国各玉米主产省的自然风险,可为农业经营提供参考,有利于保障粮食安全。[方法]文章以玉米相对气象产量为研究基础,采用气象减产率和气象产量减产变异系数两个指标对各玉米主产省的受灾情况进行评估,使用灾损率和灾害异常指数对主产省主要灾种进行识别评价,最后通过灰度重心模型对水旱灾情的空间变动情况进行分析。该文选取地跨中国三大玉米带的11个玉米主产省份为研究对象,从全国和省际两个角度进行了对比分析。[结果]自然灾害对我国玉米种植的威胁较大,各主产省份的风险度高于全国平均水平,产量波动较大。从灾种情况来看,我国最主要的农业灾害有水灾、旱灾、风雹灾和冷冻灾4种,各玉米主产省受水、旱灾害的影响最为普遍,受旱灾的影响最大,且近年来其影响有扩大趋势。从空间尺度上看,我国水、旱灾害的空间分布呈东北—西南一线,和我国镰刀弯玉米带有很大的重合部分,给我国玉米种植的防汛抗旱工作带来了很大的挑战。[结论]自然灾害对我国玉米种植造成很大隐患,必须加强玉米防灾减灾体系建设,提升玉米灾情综合防控能力。     

基于乡村振兴的河北省农业资源可持续利用评价

［目的］对农业资源可持续利用水平展开评价，为区域农业发展相关政策的制定提供理论参考，将有利于不断推进乡村振兴战略的实施。［方法］从经济可持续性、社会可接受性和生态可持续性3个方面构建了河北省农业资源可持续利用评价体系，采用熵权法和加权综合法测算了2007—2016年全省及11个地级市农业资源可持续利用水平，并探究了经济可持续性、社会可接受性和生态可持续性之间的协调度。在此基础上，采用DEA模型中的CCR模型和BCC模型探讨了全省农业资源利用的综合效率、纯技术效率和规模效率。［结果］（1）2007—2016年河北省农业资源可持续利用评价综合评价分值呈平稳增长趋势，由2007年的0315提高到2016年的0498。2007—2012年，农业资源利用的经济可持续性、社会可接受性和生态可持续性发展之间的协调度呈现递增趋势，由0760提高到0935。2012—2016年，协调度呈现递减趋势，由0909降低到0838。（2）2007—2016年河北省各市农业资源可持续利用的综合评价分值整体呈递增趋势，但地区间存在差异。整体看来，唐山市的评价分值明显高于其他各地市，其次为廊坊市和石家庄市，邢台市的综合评价分值较低。（3）2007—2016年，河北省农业资源利用的综合效率和规模效率变化趋势表现出高度的一致性。2007—2012年，综合效率小于095，处于较低的水平。2013—2016年，综合效率大于095，处于较高的水平。大部分年份存在农业机械总动力、农业从业人员、农用地面积和化肥施用量投入过多，农村人均可支配收入产出不足的现象。［结论］河北省农业资源可持续利用水平虽呈现良好的发展态势，但今后更应注重经济、社会和生态之间的协调性，推动农业资源利用的可持续性向更高水平发展。农业资源可持续利用综合效率的提升主要是依靠生产规模的优化配置，技术创新发挥的作用较小，农业生产要素的投入亟待进一步优化配置。     

农业水旱灾害的分级评估与农业保险的风险分担

水旱灾害是影响我国农业生产最重要的自然灾害,严重的旱涝灾害极易造成农业保险赔付的系统性风险。为从定量视角分析不同级别水旱灾害的风险损失,本文收集了1978年～2010年12个粮食主产省份的水灾与旱灾成灾率数据,构建了灾害波动测算模型,获得粮食主产区各年份水旱灾害的波动系数,并依据波动系数值对农业水旱灾害风险损失进行分级与评估,最后针对农业水旱灾害的超额损失和巨灾损失,从目标、思路和工具创新三个层次给出农业保险风险分担的改进对策。     

水旱灾害对我国粮食产能影响的时间变化特征分析

研究农业气象灾害与农业生产的相关关系对保障粮食安全具有积极作用,本文利用1991至2012年间全国农业气象灾害和粮食生产数据,分析了旱灾、水灾两种主要农业气象灾害的变化趋势,探讨了不同种类灾害对我国粮食生产的影响,对气象灾害受灾成灾面积与粮食单产之间的关联度进行了分析.结果表明:受灾面积呈下降趋势,且水灾受灾面积与旱灾受灾面积呈现出比较明显的反向变动特征;成灾面积虽也呈下降趋势,但水灾成灾面积与旱灾成灾面积逐渐呈现出同步波动趋势;农业水旱灾害呈明显周期性波动,且干旱致灾强度的年际波动较大;谷物单产与水旱灾害受灾面积、成灾面积等指标显著负相关.     

河北省乡村雷电灾害风险区划研究

［目的］河北省乡村雷电灾害损失严重，开展河北省乡村雷电灾害风险区划研究对于风险管理具有重要意义。［方法］文章利用2010—2016年河北省闪电定位网观测数据、河北省统计年鉴及2014—2016年全国雷电灾害汇编资料，选取地闪密度和最大地闪强度表征雷灾危险性，乡村用电量及乡村家电拥有量表征雷灾脆弱性。采用风险矩阵方法，得到河北省各区县行政单元风险估算值。［结果］河北省乡村雷灾极高风险区位于秦皇岛南部昌黎县、唐山东北部迁安市以及保定南部定州市，将风险区划结果与2014年乡村雷灾频次分布对比发现，乡村雷电多灾区和该文的高风险区有较高的重合度。［结论］风险区划结果可为河北省有关部门乡村雷电防灾减灾规划提供科学依据。     

河南新型城镇化与乡村治理耦合协调性分析

［目的］新型城镇化建设是实现全面建设小康社会的必经之路，乡村治理的有效实施是城镇化建设的重要内容，研究两者之间的耦合关系，有助于不断加快城乡一体化的进程。［方法］通过构建河南省新型城镇化与乡村治理发展水平评价体系，采用熵值法和加权法对2007—2016年新型城镇化与乡村治理发展水平展开了评价，采用障碍度诊断模型对制约该省新型城镇化和乡村治理水平的障碍因子进行了诊断，采用耦合协调度模型，探讨两者之间的耦合发展演变规律。［结果］（1）2007—2016年河南省城镇化发展水平评价分值呈明显的上升趋势，由2007年的0211提高到2016年的0788。二、三产业从业人数、亿元GDP专利授权量和城镇人口密度是该省城镇化发展进程中的主要障碍因素。（2）2007—2009年乡村治理评价分值呈上升趋势，由2007年的0444提高到2009年的0482。2010—2013年乡村治理评价分值呈现下降趋势，由2010年的0441降低到2013年的0397。2014年乡村治理评分开始上升，2016年相比2014年提高223%。农药投入、农村居民恩格尔系数和化肥投入是制约该省乡村治理水平的主要障碍因子。（3）2007年河南省新型城镇化和乡村治理之间的耦合协调度为0377，处于低度协调耦合等级。2008—2016年耦合协调度整体上由0403提高到0575，处于中度协调耦合等级。［结论］河南省新型城镇化处于良好的发展态势，但乡村治理较为落后，今后城镇化建设应以乡村治理为基础，努力实现两者的耦合协调度向更高水平发展。     

江淮地区玉米涝渍指标构建及时空特征分析

［目的］江淮地区玉米涝渍灾害严重，研究揭示区域玉米涝渍灾害时空发生规律对科学开展区域防洪减灾具有重要意义。［方法］利用1981—2010年江淮地区18个站点地面气象观测数据和农业气象资料，基于作物水分盈余指数（CWSI），引入播种前底墒，根据玉米各生育阶段涝渍敏感性差异，采用层次分析法确定阶段涝渍灾害影响权重，构建适用于江淮地区玉米涝渍等级评估的玉米综合水分盈余指数（CWSIM），并根据典型涝渍年综合指数同对应减产率的线性回归方程，划分春、夏玉米不同等级涝渍的指标阈值。［结果］(1）春玉米的轻、中、重涝指标阈值依次为： 080≤CWSIM＜101,101≤CWSIM＜123,CWSIM≥123； 夏玉米为： 109≤CWSIM＜144,144≤CWSIM＜179,CWSIM≥179。(2）各阶段水分盈余指数（WSIM）分布规律，春玉米为：出苗—拔节期、拔节—吐丝期呈由北向南的纬向增加分布； 吐丝—成熟期高值区位于安徽省西南临江一带、江苏省淮安市东部、扬州市及其周边区域，低值区位于安徽省北部及中部的中心区域、江苏省东南边缘，其余为中值区。夏玉米为：出苗—拔节期呈由北向南的纬向增加分布； 拔节—吐丝期高值区位于江苏省东北部，低值区位于安徽省中部及临江一带，其余为中值区； 吐丝—成熟期指数呈由西向东的经向增加分布。(3）江淮地区近30年，春玉米CWSIM值由北向南呈纬向增加分布。整体指数在不同时期的排序为1991—2000年＞1981—1990年＞2001—2010年； 夏玉米CWSIM值由北向南呈近辐射状条带增加分布，不同时期指数排序为1991—2000年＞2001—2010年＞1981—1990年。［结论］安徽省沿江一带是玉米涝渍害发生的重灾区，且1991—2000年较其前后10年涝情最重。     

灾害损失可控性、受灾经历与农户极端气候响应北大核心

极端气候对农业生产与食物安全构成威胁,在极端气候增多的背景下理解农户对极端气候的响应行为与方式,有助于公共政策有效应对极端气候的冲击。本文构建了一个成本收益分析框架用以解释农户响应行为规律,特别是极端气候属性和农户在极端气候下的受灾经历对其响应行为和措施选择的影响和作用机制,并用吉林、江苏和四川3省份农户微观调研数据进行实证分析。研究表明,农户对极端气候是否响应及措施选择与灾害损失可控性和农户受灾经历特点密切相关。因旱灾损失可控性高,农户对旱灾响应率高,而水灾和风灾等灾害损失可控性低,针对此类极端气候的应对必须公共政策介入。受灾经历对农户极端气候响应的影响效应存在心理阈值,即只有当受灾程度和灾害频率高到一定程度后,农户才会给予响应。就旱灾响应措施而言,农户有严重旱灾经历会明显提升其选择抗旱品种和改善灌溉技术概率,而有频繁受灾经历会明显提升其投资灌溉设施的概率。     

The Effect of the Structural Adjustment Program on the Output,Prices and Exports of Major Agricultural Export Crops in Nigeria

The primary objective of this paper is to examine changes in the level of output, prices and exports of major export crops resulting from the Structural Adjustment Program (SAP) in Nigeria. THere two main sources of data: the Central Bank of Nigeria (CBN) through its annual reports, Economic and Financial Review, and the Nigerian Federal Office of Statistics (FOS) through its Trade Summaries. Although the SAP led to appreciable increases in output and producer prices, its effects on exports were insignificant. The implications of these for the implementation of the program are explored.     

Revealing different understandings of soil held by scientists and farmers in the context of soil protection and management

This paper aims to analyse and draw together results from similar studies in England, Switzerland and France which investigated farmers’ understanding of soil and compared it with that of scientists, researchers and advisors (collectively called scientists in this analysis). A range of methods were used across the three studies and different theoretical approaches, looking at forms of knowledge, local practice of knowledge production and conceptions of reality, were employed to explain the results. Despite the different contexts, methodologies and theoretical approaches in the three studies, the results reveal similar patterns of difference in farmer and scientist understanding of soil. In the English study, farmers demonstrate a ‘know-how’ form or intuitive working knowledge of soil while advisors rely on scientifically established forms of ‘know-why’ and seek to understand and explain soil processes. Similarly in the Swiss study farmers’ and scientists’ differing perceptions are directed and shaped by their respective aims, methods and context of work. In the French study, farmers and researchers are shown to have different conceptions of soil, they attribute different meaning to the same activities, and use different words and language to describe the same features. In all three studies understanding is shown to be cultural and contextual, as such an integrative theoretical framework is proposed.     

森林生物多样性评价模型的改进

针对2002年的评价模型中的不足,提出了新的改进后的森林生物多样性变化的评价模型,并在我国第六次森林资源清查(1999～2003)资料的基础上,对1973～2003年我国森林生物多样性的变化进行了补充评价。评价结果表明:我国森林生物多样性的压力越来越大,压力指数由1973年的100,上升到2003年的199.10,上升了1.99倍;森林物种多样性总体的下降趋势已有一定幅度的改变,森林物种多样性指数增加了31.12%。森林生态系统多样性和森林生物多样性先逐渐上升,尔后又下降,第六次森林资源清查时又有所恢复,并分别上升了4.67个百分点和17.90个百分点。     

转变地质工作发展与服务方式的实践和建议

天津市地矿局注重加快转变经济发展方式，发挥地质工作优势，推进低碳清洁能源的开发利用创新和技术进步，紧紧依托地质工作的人才、技术和行业优势，加大清洁环保资源的勘查、研究、开发、利用。针对天津市水资源缺乏的情况，积极加强后备和应紧水源勘查。按照“两种资源，两个市场”的思路，通过实施中外合作勘查项目，以境外勘查工作为载体和平台，实施引进来和走出去战略，为天津市经济社会发展提供地质技术支撑。     

Trust-A monolithic panacea in land use planning?

Although trust research has been extensive and substantial, the constitution and actual merits of trust in land use planning remain nebulous. What do participants of a local land use planning process actually mean when they say they trust the planning committee? How important is participants’ trust in the planning committee in shaping their perceptions of the planning process and their cooperation in it? To explore the everyday meaning of trust in the specific context of local land use planning, semi-structured interviews with the participants of a local planning project in Switzerland were conducted (n = 9). Based on these results, the constitution and the relevance of trust in the responsible planning committee among a wider circle of participants were assessed (n = 66). The results show that participants trust the planning committee if they perceive its members as competent, honest, open, fair, reliable, reciprocating, respectful and committed. Interestingly, a considerable part of trust in the planning committee hinges explicitly on whether the committee incorporates the personal interests of the participant. Trust is indeed vital to participants’ belief that a meaningful discussion and cooperation with the members of the planning committee is possible. However, trust is neither a guarantee for people's approval of planning decisions nor for their cooperation. One implication of the findings is that in order to evaluate trust-building practice comprehensively, it is necessary to first understand the specific everyday meaning of trust for ‘real people’ in real planning processes.     

Agricultural Land in Vietnam: Markets Tempered by Family, Community and Socialist Practices

Since the late 1980s, markets involving agricultural land have emerged in the Socialist Republic of Vietnam. One major reason is that collective farms, previously a central feature of the country's political economy, ended. And a major reason for that was villagers' everyday politics gnawed the underpinnings of the collectives until they collapsed. Rural households, for the most part, wanted to farm separately. Today they do. Land is not privatized, however. Farming households have land use rights, not ownership. This tempers markets, as do other conditions arising from contending schools of thought in Vietnam about how land should be used, distributed and regulated.     

Conservation agriculture (CA) in Tanzania: the case of the Mwangaza B CA farmer field school (FFS), Rhotia Village,Karatu District,Arusha

This project was initiated to promote conservation agriculture (CA) in Tanzania so as to improve the food security and rural livelihood of small- and medium-scale farmers through the scaling-up of CA as a sustainable land management (SLM) tool as well as increasing the numbers of SLM-CA farmer field schools (FFS) in communities. The project had two phases from 2004 to 2010. It was funded by a Government of Germany trust fund and implemented by the Food and Agriculture Organization of the United Nations (FAO) and the Ministry of Agriculture in Tanzania. The project pilot districts include Arumeru (Arusha and Meru Councils), Karatu, Babati, Hanang and Moshi districts. CA has been shown to offer positive elements that could contribute to fighting hunger and poverty.     

Successful Practices in California Wine Exporting

Abstract

California is one of the world's largest wine producers, yet it has exported only a small portion of its products. Many US wineries want to pursue opportunities in foreign markets but only a few are actually doing this successfully. Therefore, this study attempts to identify the successful practices of 12 California wineries that have achieved their financial targets and other export goals. A qualitative research design of in-depth interviews was employed. Results indicate that there are 5 major success factors, with the two most important being the foreign partner relationship and top management vision and commitment to exporting.     

Time Allocation Decisions Associated with Job Market Preparation: Undergraduate Perceptions versus Market Realities

A survey of agribusiness firms identifies characteristics associated with above average starting salary offers in the allied fields of agribusiness, agricultural economics, business, and economics. A complementary survey is made of students at Texas A&M University and University of Georgia. Results show that firms value work experience and leadership experience more than students do, whereas students value raising grade point average and interview preparation more than do firms. Students seeking a firm's maximum starting salary offer will need to enhance academic performance with substantial work experience and leadership experience.     

Developments in the Doha Round and WTO dispute settlement: some implications for EU agricultural policy

Progress in the Doha Round is assessed against the changes tothe common agricultural policy (CAP) brought about by the Fischlerreforms of 2003–2004, and that proposed for sugar. Anelimination of export subsidies could place EU exports of processedfoods at a competitive disadvantage because of high sugar andmilk prices. Provided the single payment scheme falls withinthe green box, the likely new limits on domestic support shouldnot be problematic for the post-Fischler CAP. However, an ambitiousmarket access package could open up EU markets and bring pressurefor further reform. If there is no Doha agreement, existingprovisions will continue to apply, but without the protectionof the Peace Clause; and increased litigation is likely. FurtherCAP reform is to be expected.