德州市0℃界限温度变化及其对粮食作物的影响

[方法]利用德州市11个气象观测站1971~2014年逐日平均气温资料,采用五日滑动平均、经验频率法、趋势分析法,[目的]对该市0℃界限温度初(终)日、间隔日数、积温变化特征、稳定通过界限温度80%的保证率及其对粮食作物的影响进行分析。[结果]研究表明:德州地区≥0℃的初日呈显著提前趋势,增长速率为4.12d/10年,主要集中在2月中下旬;终日有延迟趋势,推后速率为0.27d/10年,主要集中在12月上旬;间隔日数显现出略增加趋势,增加速率为4.39d/10年,平均为288d;≥0℃活动积温呈现明显增加趋势,增温速率为117.2℃/10年,平均为4 982.5℃。全市稳定通过0℃界限温度80%保证率的初日范围为3月1~6日、终日范围为12月9~17日、积温范围在4 939.7~5 295.4℃之间。[结论]气候变化使当地热量资源增加,夏玉米等作物生长期延长,冬小麦播期有所推迟,返青期、成熟期提前全生育期天数缩短,对粮食作物造成的影响还需进一步进行综合分析。     

贵州省太子参适生地等级划分的研究

[目的]根据野生太子参实生地的生态因子,在贵州省寻找适于太子参生长区域,为太子参在贵州省的生产布局提供科学依据。[方法]查找野生太子参标本,寻找太子参实生地,应用Arc GIS从气候栅格数据库(年均温、3月平均温、7月平均温、1月平均温、湿度、年降水量、日照)、土壤数据库和100hm~2的地形栅格数据库中采集野生太子参实生地生态因子数据420组;以此为依据,利用中药材产地适宜性分析系统(TCMGISⅡ)分析贵州省被栅格化的生态因子值,并从中寻找与实生地生态因子相似的区域,作为太子参在贵州省的适生区域。[结果](1)太子参实生地生态因子范围:年均温7.3~21.4℃;3月平均温-6~12℃;湿度58.8%~82.1%;日照991~2 646h/年;年降水量556~1 410mm;7月平均温8.9~27.1℃;1月平均温-11~7.6℃;土壤为暗棕壤、紫色土、棕壤、酸性粗骨土、黄棕壤、粗骨土、暗棕壤、黄红壤、黄棕壤、暗黄棕壤、褐土。(2)在贵州省找到的相似度为80%~100%的适宜太子参种植区域。[结论]威宁、赫章两县作为最适种植区;六盘水市钟山区、水城县、纳雍县、织金县、毕节市、普定县、大方县、贵阳市、平坝县、清镇市、修文县、黔西县、安顺市、正安县、金沙县、绥阳县、六盘水盘县、六枝县作为适宜种植区。     

新型农业经营主体与普通农户之间资源流动关系分析——以湖北省宜昌为例

[目的]通过研究新型农业经营主体与普通农户之间资源流动的关系,为发挥新主体的规模优势、提高普通农户的生产效率提供依据。[方法]以湖北省宜昌市农业生产过程为研究对象,参照普罗塔和贝雷斯福德构建的多元关系网络,立足于生产关系角度,建构两主体之间土地、劳动力等重要生产、生活资源的流动关系。[结果](1)宜昌市随着从事家庭经营的人数的缓慢下降第一产业的劳动力呈现下降趋势,合作社和家庭农场得到了较大发展,部分地区的特色农业得到了发展;(2)宜昌市流转土地面积占总耕地面积的比例为5%~15%,平均比例为8%左右,涉及土地流转的农户数约占总农户数的26%。[结论]新主体兴起之下普通农户的相对地位下降,生产积极性不足,面临着高交易成本、高市场风险和低生产效率的困境;逐年增加的抛荒土地减少了实际土地耕种面积,在土地流转的推动下土地资源更多地流向了新主体,普通农户的土地细碎化更严重;农村劳动力资源在城镇化的发展之下快速流进城市,普通农户逐渐成为土地资源的提供者。     

1960—2013年黄土高原地区干湿界线时空变化特征

［目的］研究气候变暖背景下黄土高原地区干湿区界线动态变化过程。［方法］利用1960—2013年黄土高原地区的76个气象站点逐日平均气温、平均最低气温、平均最高气温、降水、平均风速、日照时数、相对湿度数据,采用Penman Monteith模型计算了黄土高原地区的潜在蒸散量,进而计算干燥度指数。运用线性趋势法、Mann Kendall趋势检验法对黄土高原地区的干燥度趋势进行了分析,运用反距离加权差值（IDW）研究了干燥度界线的动态变化格局。［结果］近54年黄土高原地区干燥度指数呈微弱增加趋势,四季变化中春季呈上升趋势,冬季为减小趋势,夏、秋季变化不明显,空间上兰州以西,银川—太原一线北干燥度指数呈减小趋势; （2）干旱与半干旱区界线在1075°E, 375°N以东表现为经向变化,以西为纬向变化,近54年干旱区范围变化不明显; （3）半干旱与半湿润区界线南北方向波动变化明显, 20世纪90年代向南扩张到华家岭—六盘山—平凉—庆阳—延安—三门峡—长治一线以南,半干旱区面积达到最大,比20世纪60年代的半干旱区范围扩大14%,比2000—2009年大5%左右。［结论］近54年黄土高原总体上地区呈干旱化趋势,半干旱区面积扩大,半干旱与半湿润区界线年代际南北波动频繁,变化范围大,半干旱区是黄土高原地区气候变化的敏感区。     

退耕对县域耕地压力效应的影响分析研究——以武隆县为例

[目的]客观科学地评价退耕还林工程对县域耕地压力效应的影响。[方法]文章以乌江流域典型县——武隆县为例,通过实际调查和运用耕地压力指数模型来分析退耕还林工程对耕地压力效应的影响。[结果]近15年来,退耕还林工程面积与农村剩余劳动力转移相关性R~2=0.934 2;研究区退耕还经济林方式下存在林下种植现象,其产生的"实际"人均耕地面积为0.204hm~2/人,比正常人均耕地面积0.164hm~2/人增加了0.04hm~2/人;研究区粮食总产量受到退耕还林工程的影响甚微,但退耕粮食补贴占粮食总产量比例随退耕面积逐渐增大而增大,且处于2.6%~20.9%之间,平均为17.2%;退耕粮食补贴在减缓区域耕地压力状态比退耕转移农村剩余劳动力和林下种植方式下明显,但人均粮食占有量的提高会极大地增加区域的耕地压力状态。[结论]总体上,退耕对县域耕地压力效应具有正效应,对客观地总结评价以及深化退耕还林工程,有序推进新一轮退耕还林工程规划设计具有重要理论和实践指导意义。     

外源硒对小麦品质特性及籽粒硒含量的影响

为了解不同外源硒不同处理对小麦产量品质特性及籽粒硒含量的影响,笔者在灌浆期叶面喷施4种不同外源硒(硒酸盐、亚硒酸盐、纳米硒及富硒有机肥),研究其对小麦籽粒硒含量、产量及品质特性的影响。结果表明,在灌浆期叶面喷施外源硒,小麦西农979产量及其构成因子都出现不同程度的增长,但不同处理方式增产量均没有存在显著的差异,其中当喷施52.5g/hm~2(以纯硒计)、兑水1500L时效果最佳,增产幅度最大为7.14%;小麦籽粒硒含量均随着喷施量的增加而增加,纳米硒较其它硒源在促进硒富积方面达到极显著差异水平(P0.01);灌浆期叶面喷施不同外源硒对小麦籽粒的容重、湿面筋含量、拉伸面积和吸水率、蛋白质组分清蛋白和球蛋白均没有显著影响,但对小麦籽粒的硬度、蛋白质含量、沉降值、稳定时间、醇溶蛋白及谷蛋白有不同程度的影响,不同的硒肥之间存在着一定的差异。在促进小麦产量品质特性和硒富积方面纳米硒较富硒有机肥、亚硒酸钠及硒酸钠有正向显著差异。     

科技经纪人与农业科研成果的推广与应用

[目的]通过研究新型农业经营主体与普通农户之间资源流动的关系,为发挥新主体的规模优势、提高普通农户的生产效率提供依据.[方法]以湖北省宜昌市农业生产过程为研究对象,参照普罗塔和贝雷斯福德构建的多元关系网络,立足于生产关系角度,建构两主体之间土地、劳动力等重要生产、生活资源的流动关系.[结果](1)宜昌市随着从事家庭经营的人数的缓慢下降第一产业的劳动力呈现下降趋势,合作社和家庭农场得到了较大发展,部分地区的特色农业得到了发展;(2)宜昌市流转土地面积占总耕地面积的比例为5%~15%,平均比例为8%左右,涉及土地流转的农户数约占总农户数的26%.[结论]新主体兴起之下普通农户的相对地位下降,生产积极性不足,面临着高交易成本、高市场风险和低生产效率的困境;逐年增加的抛荒土地减少了实际土地耕种面积,在土地流转的推动下土地资源更多地流向了新主体,普通农户的土地细碎化更严重;农村劳动力资源在城镇化的发展之下快速流进城市,普通农户逐渐成为土地资源的提供者.     

近30年来我国粮食产量波动影响因素分析

[目的]根据粮食产量波动特征,从自然因素、科技因素(物质装备)、社会经济因素和农业生产条件等方面对粮食产量的影响进行量化分析,为科学合理地制定农业政策,保障我国粮食安全提供理论依据。[方法]文章利用HP滤波法分析1978—2010年我国粮食产量波动特征,并采用灰色关联与层析分析相结合的综合评价法定量分析不同波动周期各影响因子对我国粮食产量波动的影响度。[结果](1)改革开放以来,我国粮食产量经历了完整的6个波动阶段,平均波动周期为6年;(2)除1994—2000年,各波动周期的粮食产量受科技因素的影响最大,且影响日益显著,影响度从1978—1981年的37. 0%增加到2006—2010年的48. 3%,其中,有效灌溉面积的影响增大趋势最为明显,其次是农业机械总动力,化肥施用量的影响呈减弱趋势;(3)社会经济因素对粮食产量的影响呈波动性增加的规律,2006—2010年影响度达到24. 9%;(4)农业生产条件对粮食产量的影响在20世纪80年代初期与科技因素基本持平,此后,除1994—2000年,与科技因素的影响度差距越来越大,到2000—2006年对粮食产量的影响度仅为16. 6%,其中,耕地面积的影响度下降最多,到2006—2010年,影响度仅为1. 1%;自然因素对粮食产量波动的影响最小,且较为稳定,除1985—1988年影响度达到24. 3%,其余波动周期均在8. 7%~12. 4%之间,2006—2010年影响度为10. 2%。[结论]完善农田水利灌溉体系,加强对农业机械指导的"重科技"举措比单纯增加后备耕地数量、改善应对气候变化与自然灾害能力的"靠资源"发展更为有效;加大农田水利投入,完成灌区续建配套与灌排泵站更新改造是目前最重要的发展方向。     

四川省粮食生产变化及供给侧结构性调整——基于1985~2016年统计数据

［目的］对四川省粮食生产变化、供给侧结构进行分析,结合政策提出供给侧结构性调整对策,为四川省粮食供给侧结构改革提供理论依据。［方法］采用数理统计法和比较分析法,应用 Excel软件对1985~2016年四川省粮食总产和主要粮食作物产量、粮食单产和主要粮食作物单位产量、粮食总播种面积和主要粮食作物播种面积、人口数量等数据信息进行系统化整理,统计和比较分析四川省粮食生产的动态变化及其供给侧结构特征。［结果］（1）总产量基本稳定在3000~3500万t之间, 32年间增产23年,减产9年。近11年来单产连续增长,变化幅度范围为4218.9~5397.5kg/hm2,涨幅为21.8%。播种面积近年来基本稳定在640万hm2。（2）玉米的总产量增产贡献最大,中稻在减产中份额最多,小麦的产量连年持续减少,豆类的产量总体持续增加,薯类产量增加多于减少。全年粮食以及中稻和玉米在2016年单产水平达到最高,其中玉米增幅最大,其次为薯类。几种主要的粮食作物播种面积占比为95%~99%。中稻占比最大,其次是小麦,两者占比高达50%左右。其他作物播种面积占比逐渐增加。（3）口粮总消费量总体呈现下降特征,与粮食总产量相比,足以满足口粮需求; 但饲料和酿酒用粮需求缺口较大,需要从省外调入,调入品种主要是玉米、小麦和杂粮; 全省粮食供求形势产不足需、转化用粮缺口较大。居民粮食消费由主要满足量的需求升级为注重满足质的需求。［结论］（1）粮食总产量总体平稳波动增长。总产量变化因素中,单产贡献率大于面积贡献率;（2）粮食单产总体逐步提高,全年粮食以及中稻、玉米单产水平突破了历史水平,单产受中稻单产影响最大;（3）粮食作物播种面积基本稳定。中稻和小麦占比最高。玉米、薯类、豆类播种面积逐年增加;（4）口粮总消费量整体减少,饲料和酿酒用粮缺口较大,全省粮食供求紧张、转化用粮缺口较大。城乡居民粮食消费急需由量到质升级。     

Price transmission between products at different stages of manufacturing in forest industries

The theory of demand and supply implies a positive relationship, or “price transmission” between the prices of products at different stages of manufacturing. This relationship was investigated with quarterly prices of softwood stumpage in the US South, and national prices of forest products, from 1977 to 2002. All prices, net of inflation, were found to be nonstationary and there was no evidence of co-integration between prices. Vector autogressive models, augmented by Granger causality tests and multiplier analysis showed that there was a one-to-one permanent positive response of the southern sawtimber stumpage price to a permanent change in the national lumber price. There was also a one-third permanent positive response of the national paper price to a permanent change in the national pulp price. There was no relation between regional pulpwood prices and national pulp or paper prices. When price transmission was significant, the full adjustment took about 2 years.     

Application of an ecosystem function framework to perceptions of community woodlands

Owners, local residents, government, and conservation organisations can express divergent preferences in the development and management of local woodlands. The perceptions of these four groups were examined, in the context of three community woodlands in Eastern England, using an ecosystem function framework. In a pilot study, residents were able to allocate a relative importance to woodland ecosystem services which were then related to “regulation”, “habitat”, and “production” or “information” functions. However residents also placed importance on negative services or “dis-services” associated with the woodland ecosystem. Therefore a fifth category of “dis-services” was included in the main survey which included 84 local residents, three woodland owners, three government institutions, and six representatives from conservation groups. Each of the four groups placed greatest importance on services associated with habitat (16–39% of the total importance) and information (30–50%) functions suggesting, in this example, mutual interest in the use of woodlands as a habitat or recreational resource. By contrast a potential area of difference was the particularly high importance placed by one owner on dis-services such as fly tipping. In addition the woodland owners placed higher importance (10–20%), than local residents and conservation groups (7–9%), on the productive services of the wood. This suggests a need for communication when production-related operations affect recreation. The ecosystem function framework appears to be a useful approach for highlighting potential tensions and areas of mutual interest in the management of semi-natural ecosystems.     

In Vino ‘No’ Veritas: impacts of fraud on wine imports in China

China is one of the largest wine importing countries in the world and is poised for continued import growth in the future. Increased wine purchases throughout China have given rise to persistent fraud where fake wines are packaged and sold with counterfeit contents and labels. For exporting countries like France, counterfeit wines displace market share, damage foreign brand reputation, and cause distrust in consumers who are aware of counterfeiting problems throughout the country. We examine the impact of fraudulent wine events (as measured by negative media reports) on Chinese wine demand differentiated by supplying country. We employ the Rotterdam demand system and a switching regression procedure to estimate import demand and compare results across different media variable specifications. Results consistently show that negative reports disproportionately affect French wine regardless of how the media variable is specified. This is not surprising because most fraudulent events involve French wine counterfeits.     

An evaluation framework for earthquake-responsive land administration

In recent years earthquakes and their secondary hazards have claimed the largest number of lives of all large natural disasters. Some of the world’s most earthquake-prone zones are also areas of high population density. The impact is magnified by vulnerability factors including non-enforcement of building codes, knowledge gaps, urban poverty and poor governance capacity to manage and reduce earthquake risks. Poor security of land tenure and property rights increases the vulnerability of people and affects their ability to respond to natural disasters.Earthquake recovery and reconstruction provides very significant challenges for land agencies, with these challenges differing from one country to the next due to differences in the local context. Drawing on contrasting case studies in Haiti, Nepal and New Zealand this paper identifies the common post-earthquake land administration functions and challenges that may apply to many contexts. These lessons provide land agencies and other key stakeholders with a summary of the challenges an earthquake poses for land administration at different post-disaster stages. We also discuss the policy and regulatory, institutional, operational and preparedness lessons for land administration. From these lessons we propose a framework for evaluating the earthquake-responsiveness of a land administration system. This framework can be used by a land agency in an earthquake prone region, or where an earthquake has recently occurred, to assess what challenges to land administration might occur in the event of an earthquake, and the preparedness of their land administration system.     

Agrarian Poverty,Nutrition and Economic Class – A Study of Gujarat,India

This paper analyses poverty and calorific undernourishment in the Indian state of Gujarat, where high and market‐led industrial growth has resulted in rapid economic improvement. The study is carried out through a combination of secondary and survey‐based data. We conclude that the neoliberal agenda of uncontrolled, outward‐looking growth has not resulted in significant reduction of poverty or malnourishment in rural areas. Furthermore, while land ownership is officially used as a proxy for wealth distribution, class position appears a better predictor of poverty status in the rural areas than landownership per se. At the policy level, there is a need to revive the agrarian economy and create new non‐agricultural assets, and the primary focus in the state must shift to the distribution of created assets rather than a single‐minded focus on growth.     

Does sustainable agricultural growth require a system of innovation? Evidence from Ghana and Burkina Faso

This paper tests the ‘systems of innovation’ hypothesis for a selection of crops in Ghana and Burkina Faso that have shown significant growth in production over an approximately 20-year period. The question is whether such growth can only occur if supported by a system of innovation. Using two indicators (a common understanding on objectives and priorities, and a high level of interactivity), we find little evidence for the existence of anything that might be considered a high functioning system of innovation.     

Local impacts of industrial tree plantations: An empirical analysis in Indonesia across plantation types

The values ascribed to industrial tree plantations are often controversial. Hence knowledge of their perceived impacts is important for improving their integration in rural landscapes. In 2016 we conducted household surveys with 606 respondents living in villages adjacent to acacia, teak and pine plantations across three islands in Indonesia (Java, Borneo, Sumatra). Results show that perceptions toward pine and teak plantations tend to differ from those toward acacia pulpwood plantations in several ways. Pine and teak plantations are perceived to have a higher number and variety of benefits and services, a higher number of positive impacts, a better environmental record, and to present more opportunities to local people for use of plantation land and products for improving rural livelihoods. In addition, we find that villagers around acacia pulpwood plantations tend to seek economic development and infrastructure to open up remote areas, yet their expectations were often only partially met. Recommendations from our analysis include: the role of the State in plantations must be clarified and potentially reinforced; the role of institutions as intermediaries is fundamental; and contributions by communities to design of management plans should be accommodated.     

Upstream demand for water use by new tree plantations imposes externalities on downstream irrigated agriculture and wetlands*

Large‐scale tree plantations in high rainfall upstream areas can reduce fresh water inflows to river systems, thereby imposing external costs on downstream irrigation, stock and domestic water users and wetland interests. We take the novel approach of expressing all benefits and costs of establishing plantations in terms of $ per gigalitre (GL) of water removed annually from river flows, setting upstream demands on the same basis as downstream demands. For the Macquarie Valley, a New South Wales sub‐catchment of Australia’s Murray‐Darling Basin, we project changes in land and water use and changes in economic surpluses under two policy settings: without and with a policy requiring permanent water entitlements to be purchased from downstream parties, before plantation establishment. Without the policy, and given a high stumpage value for trees ($70/m³), upstream gains in economic surplus projected from expanding plantations are $639 million; balanced against $233 million in economic losses by downstream irrigators and stock and domestic water users for a net gain of $406 million, but 345 GL lower mean annual environmental flows. With the policy, smaller gains in upstream economic surplus from trees ($192 million), added to net downstream gains ($138 million) from sale of water, result in gains of $330 million with no reduction in environmental flows. Sustaining the 345 GL flow for a $76 million (406–330) reduction in gains to economic surplus may be seen to cost only $0.22 million/GL; but this is much lower than the market value of the first units of that water to agriculture and forestry.     

土地学科的建设和发展——"土地学科发展规划研讨会"综述

中国土地科学学科发展已取得很大成就,表现为专业教育和人才培养成绩突出、初步形成学科体系、取得大批研究成果.而存在的问题主要是基础理论研究欠缺、独特的土地科学研究方法体系尚未形成、研究角度单一、学术交流质量不高和学科带头人的影响力不足.土地科学学科发展目前面临着巨大的机遇和挑战,应明确土地科学学科发展的基本思路、发展目标及2010-2020年的主要建设任务和保障措施.     

Underpayment of Small Producers of Coffee and Cocoa in Sierra Leone

Fieldwork shows that many Sierra Leonean producers do not receive the official producer price for their coffee and cocoa, due to the concentration of buying stations, credit relations, the small quantities offered for sale, and the lack of marketing knowledge of the numerous and unorganized farmers. To the traders underpayment may seem economically justifiable to a certain extent, but to the farmers it means poverty and debt. A new village marketing centre project aims at remedying this situation and has already led to higher prices. Although no longer allowed to take their "just" share from the producers, traders are still willing to deal with the new centres.