Modelling the impact of interventions on the dynamics in village poultry systems

There are many technical possibilities to improve free-range and backyard poultry keeping. Rural households, however, are not adopting these technologies widely. This paper presents a model approach for ex ante evaluation of interventions in village poultry systems. The dynamic deterministic computer model considers mortality, egg production, reproduction, offtake, and their interrelationships. In the base situation, the model reflects the behaviour of a relatively stable village poultry flock. The model was used to explore how interventions influence the dynamics of a village poultry flock. Over the simulated period of three years, NCD (Newcastle Disease) vaccination, daytime housing, supplementary feeding, and control of broodiness each had a positive effect on bird offtake, egg production, egg offtake, and flock size. Crossbreeding had a highly negative effect on these key variables. The impact of interventions is also related to the use of the available resources. Cost–benefit calculations for the Tigray region in Ethiopia and village poultry research sites in Kenya indicated that NCD vaccinations were economically most effective. Housing and crossbreeding had a highly negative impact on net returns. When applied with situation-specific input data, the model can be used in the first stages of research and development approaches to support decisions on priorities of projects in village poultry production.     

地理信息技术在土地整治中的应用及发展

土地整治是提高耕地质量,实现更好保护耕地的重要措施之一。地理信息技术作为一种综合技术,是实现土地整治工作高效化和智能化的重要工具。通过对当前地理信息技术在土地整治中的应用进行分析,主要对土地整治工作中3S（RS、GIS和GPS）技术的应用情况进行阐述,详细说明了3S技术在土地整治项目踏勘阶段、可行性研究阶段、规划设计阶段、项目实施阶段以及后期管护阶段的应用情况。提出了建立土地整治信息系统,将3D分析功能与可视化技术更好地应用于土地整治中的建议。      

GIS技术在农村饮水安全工程评价系统中的应用

针对面广量大的农村饮水安全工程,如何提高工程管理效率是运行管理中的主要问题。目前,水利信息化已成为发展方向。通过建立农村饮水安全工程数据库,结合工程空间分布特点,引入GIS技术,应用对象编程方法,建立了基于空间管理的农村饮水安全工程评价系统。利用模糊综合评价模型对工程评价,首次实现了工程评价与GIS的结合,方便了农村饮水安全工程运行、管理。应用实践显示,系统操作性强,评价结论可信,可推广到其他市县工程管理中。      

土地综合整治项目实施效益评价——基于AHP-PCE模型

为研究土地综合整治工程实施前后项目区总体建设效益情况,明晰土地综合整治工程建设过程中存在的问题及可提升潜力指标,以法库县龙家村土地整治项目为例,从经济效益、社会效益、生态效益和景观效益4个方面选取14个评价指标,采用多层次模糊综合评价法测算各效益分值及综合分值,并划分评价等级。研究结果表明：项目区土地综合整治工程综合效益分值为82.10,综合评价等级为良好。经济效益、社会效益、生态效益和景观效益表现为“一优三良”。其中,社会效益分值为86.15,评价等级为优秀;经济效益、生态效益、景观效益分值分别为80.74、82.12和79.41,评价等级均为良好。经济效益、社会效益、生态效益和景观效益均有所提升,但经济效益和景观效益与项目预期建设目标存在差距,其中新增耕地指标、项目区总产值指标及景观丰富度指标有较大提升潜力。     

江苏沿海地区土地整治项目成效综合评估

为了对江苏省沿海地区大量土地进行整治,针对沿海地区盐碱土改良增产效果进行量化以获取整治效果.以江苏省沿海地区的4个土地整治项目为例,从资金投入、过程管理、工程实施、综合效益4个方面选取了27个评价指标组成效益评价指标体系,用统计类比、专家咨询等方法构建了土地整治综合评估模型,得到综合效益评价值,提出了相应的建议和措施,为沿海地区土地整治成效的定量化评价提供了科学依据.结果表明:该研究区的4个土地整治项目实施的总体成效较为显著,大部分指标达到计划要求,具有显著的经济、社会和生态效益,但是各项目单项指标成效评估差距较大,土地整治项目综合评价还有较大的提升空间.评价结果为沿海地区在土地整治实践中有针对性地改进提供了依据和借鉴.     

新形势下土地整治工程发展趋势

土地整治已成为一项重要的惠民利民工程。分析新形势下土地整治工程发展趋势,对指导土地整治工程,实现政府职能转变有重要意义。在阐述土地整治发展历程基础上,总结出当前土地整治工作中存在准备工作不充分、规划设计及项目施工不尽合理以及监管不力等不足;进一步提出从加强监管、加大宣传和加大后期管护力度3个方面出发,提高土地整治工程综合效益。最后结合当前经济社会发展趋势,得出土地整治工程主要向多元化发展,“土地整治+扶贫”等已成为趋势,“大而强、小而精”的土地整治成为今后两个发展方向。      

Gains from crop diversification in the Sudan Gezira scheme

Land allocation in Gezira irrigation scheme (the Gezira) has, for the most part, been based on the political judgement of the government rather than economic criteria. This paper determined optimum crop combinations for the Gezira using the mean-variance (M-V) model. This large-scale gravity-irrigated project which was started for export cotton cultivation on 27,372 feddan (11,496 ha) in 1927 has now expanded to over two million feddan, and has a multi crop production system. Sources of production uncertainty include government control of prices, often announced after planting, and crop area in favor of cotton. Diversification was analyzed under various levels of risk using, in contrast to what is in the reviewed literature, both cross sectional and time series farm level data. The cross-sectional data comprised of net farm returns of 100 farmers for the 1987/1988 season, and the time series data were average net farm returns from the same area from 1971 to 1988. Cropping decisions in the Gezira are mostly based on cross-sectional data from a sample of tenants in the preceding season. This paper estimated variance and covariance parameters of observed net margins of both sets of data and found significant differences in the results. The certainty equivalence results used to evaluate crop diversification showed that current policies of controlling crop acreage lead to inefficient land use; and that farmers diversify into wheat and groundnuts out of cotton when cross-section data were used; and from groundnuts to cotton and wheat when time series data were used.     

土地整治工程中水平梯田田坎断面优化

为了研究土地整治工程中水平梯田田坎断面设计方案优化问题,分析了不同田坎高度和外坡角度对田坎占地率和挖填方工程量的影响,在此基础上,以田坎占地率和挖填方工程量作为评价指标,对田坎断面设计方案的综合评价进行了初步探讨。研究表明,田坎越高,外坡越陡时,田坎占地率越小,即有效耕作面积越大;田坎越低,外坡越缓时,挖填方工程量越小,即工程成本越小。表明田坎占地率与挖填方工程量具有相互对立性。因此,在土地整治工程水平梯田田坎断面设计过程中,应因地制宜,合理确定各评价指标权重,以确定最优田坎断面设计方案。      

对当前农村土地产权制度改革的思考

针对当前农村土地产权权能的残缺特点,提出完善我国农村土地产权制度的建议。     

水中长期供求规划实施对云南省农业供水安全影响分析

全国水中长期供求规划编制目的之一是着力满足农业用水需求,提高农业灌溉的用水供水保证保障能力。结合云南省农业供水特点,建立农业供水安全评价指标体系,采用模糊层次综合评价方法对规划实施前后的云南省农业供水安全进行评估。结果表明,2010年云南省农业供水处于橙色预警状态,规划提出重点水源、节水灌溉和抗旱应急水源等重大工程的实施能有效提高农业供水的保障程度,规划实施效果明显。     

Evaluation of productive rural land patterns with joint regard to the size,shape and dispersion of plots

With a view to its use in relation to land consolidation programmes, we present an approach to evaluation of land distributions that aggregates the influences of the size, shape and dispersion of plots on productivity and is designed for computer implementation in a geographical information system. It is envisaged that it will be useful for identification of areas in which land consolidation is required, for evaluation of consolidation projects, and for consolidation project optimization.     

旱塬区新增耕地质量和粮食产能影响因素分析——以占补平衡项目为例

为揭示渭北旱塬区耕地占补平衡项目对粮食产能的影响,以冬小麦和春玉米为量化标准,采用Logistic回归模型,对典型的渭北旱塬区千阳县2017年占补平衡项目新增耕地粮食产能影响因素进行研究;同时,对项目实施前后新增耕地土壤理化性质变化进行分析.结果表明:通过占补平衡项目实施使新增耕地等级提升了1—2个等级,且新增耕地中水浇地面积占比越大,新增耕地等别越高,单位面积上水浇地较旱地的粮食产能提高率增加25%.随着项目实施年限增加,土壤理化性质不断得到改善,总孔隙度、大团聚体、水稳性团聚体和微团聚体均显著变大(P<0.05),土壤结构破坏率显著减小(P<0.05),抗侵蚀能力显著提高(P<0.05).土壤有机质质量比显著提高(P<0.05),土壤养分状况不断改善.新增耕地的面积、等别、基础设施、单位面积投资、年限等因素均与粮食产能之间呈现不同程度的正相关关系;各因素对新增耕地粮食产能影响程度,按因素排序由大到小表现为等别,面积,基础设施,年限,投资.     

基于分等因素组合和物元分析的耕地质量潜力研究

为了科学测算和评估耕地质量潜力,以河北省涿州市为研究区,以400 m×400 m规则网格为评价单元,基于涿州市2013年耕地质量等别数据,运用改进的因素组合法、层次分析法、物元分析模型等,分别计算耕地整治的自然质量潜力和利用质量潜力。研究结果表明:灌溉保证率和有机质含量是涿州市耕地自然质量的可改造限制因素,且灌溉保证率是主导限制因素;涿州市耕地基础设施水平整体偏低,应通过水利灌排、田间道路修建、增加防护林等工程改善利用条件。通过提升可改造限制因素和影响土地利用系数的指标值,涿州市耕地质量国家自然等、国家利用等可分别提升0.53等、0.73等。提出的研究方法为精细化评估区域耕地质量、制定县域土地整治规划提供了方法参考。     

基于熵组合权重的农村居民点复垦现实潜力估算

有效、合理地估算农村居民点复垦潜力,特别是现实潜力,是顺利开展农村居民点复垦的重要环节。为此,以永川区23个乡镇为例,选取自然条件、社会因素以及经济因素等7个指标,构建了农村居民点复垦现实潜力评价指标体系,最后结合信息熵法、AHP法、最小信息熵原理以及综合评价法对研究区的农村居民点复垦现实潜力进行了估算并运用层次筛选法将研究区划分为Ⅰ级优先复垦区、Ⅱ级重点复垦区、Ⅲ级一般复垦区和Ⅳ级适度复垦区。农村居民点复垦现实潜力估算以及评价分级,可为土地整治规划以及确定、实施农村居民点复垦项目提供决策依据。     

乡村振兴战略背景下沉睡的农村土地资源盘活的对策

土地资源是我国乡村振兴战略实施的核心资源,全国各地通过系统性地推动农村土地流转经营权“搞活”,沉睡的农村土地资源焕发了新生命,提升了乡村振兴战略推进的动力。本文主要论述乡村振兴战略背景下沉睡的农村土地资源盘活的对策。      

Modernization of furrow irrigation in the South-East of France automation at field level and its implications

Surface irrigation rehabilitation in the South-East of France has shown success ever since the beginning of its development in the early 1980s. The gradual introduction of surface distributors, mechanized or automated has resulted in water savings and above all in decreased labor input. The distributors used are: gated pipes, layflat tubing, buried low pressure pipe and cablegation. They are used over an ever increasing area which attained about 1000 ha in 1987.Improvement is made in furrow head distribution as well as in field levelling, furrow flow evaluation, flow control at the head of the furrow and in the collective system.The effect of a modernized system and improved knowledge has been to make automated surface irrigation (particularly furrow irrigation) a modern application method in competition with techniques such as sprinklers and localized irrigation.Abbreviations ASAE American Society of Agricultural Engineers - CEMAGREF Centre d'Etude du Machinisme Agricole du Génie Rural des Eaux et des Forêts, Division Irrigation, BP 5095, 34033 Montpellier et BP 31 Le Tholonet 13612 AIX - ENGREF Ecole Nationale du Génie Rural des Eaux et des Forêts, Département Maîtrise de l'Eau et Développement, BP 5093, 34033 Montpellier - IRAT Institute de Recherche en Agronomie Tropicale, Zolad Mini Parc Bt7, 34100 Montpellier - P.V.C. Polyvinyl chloride - RNEDHA Réseau National Expérimentation Démonstration secteur Hydraulique Agricole, BP 5095, 34033 Montpellier - SCP Société du Canal de Provence et d'Aménagement de la Région Provençale, BP 100, 13603 AIX en Provence     

重庆市永川区水稻生产全程机械化技术实践

2017年,重庆市永川区组织实施了农业部主要农作物生产全程机械化示范项目（水稻生产全程机械化）。通过精心组织实施,全面完成了项目各项建设任务,达到预期效果。通过项目的实施,示范区内水稻生产在耕地、播种、植保、机收、烘干和秸杆处理关键环节实行了全程机械化作业,经济效益、社会效益和生态效益明显,示范区水稻生产耕种收综合机械化水平达到98.5%,形成了一套适合永川区水稻生产全程机械化的技术模式及农机装备配置模式。      

基于土壤生态环境的耕地资源保护评价

土地开发和利用，能够直接影响到土地生态系统的发展和功能效果，充分有效地开展耕地资源保护方面的综合评价工作，能够有效发挥土地资源的优势和作用。从土壤生态环境角度出发，综合性地评价耕地资源，以便更好地保护耕地资源。从耕地资源保护综合材料与方法入手，针对耕地资源保护评价结果进行全面细致的分析和说明，并提出了一些推进耕地资源生态环境开发利用的良好建议，为充分提升耕地资源的总体应用水平提供良好基础。      

不同矿化度对层状土入渗规律的影响研究

为研究不同矿化度水分对沙壤土中壤土夹层入渗规律的影响,设置4种矿化度处理,分别为0,1,3,5g/L,进行室内土柱垂直一维积水入渗试验。结果表明:壤土夹层对不同矿化度水分均有阻渗作用;各处理累积入渗量在湿润锋到达夹层界面前随时间呈非线性变化,通过夹层后随时间呈线性变化,各处理稳渗率大小关系为V(3g/L)>V(5g/L)>V(1g/L)+>V(0g/L);矿化度为0~3g/L时,累积入渗量、入渗后土壤含水率均随矿化度提高而增大;入渗结束后,各处理夹层界面上层土壤脱盐,夹层界面下层土壤积盐。     

Land use and land cover classification in the irrigated Indus Basin using growth phenology information from satellite data to support water management analysis

Water resources planning and management is fundamental for food security, environmental conservation, economic development and livelihoods. In complex basins like the Indus Basin, water is utilized by different land cover and land uses. Up to date information about these Land Use and Land Cover (LULC) classes provide essential information on the water flow path. Traditionally, landscapes are described by cover type. For water management analysis, the information on land use is vital. To this end, a classification of LULC in the Indus Basin (covering 116.2 million hectares of Pakistan, India, China and Afghanistan) has been made. Vegetation index images freely available from SPOT-Vegetation satellite were used to describe the phenological cycle of all agro-ecosystems at a spatial resolution of 1 km × 1 km. An unsupervised clustering technique was adapted to classify 27 land use classes. Ground information and expert knowledge on the growing patterns of crops was used to label the resulting LULC classes. This helped to discern specific crops and crop rotations. An error matrix was prepared using ground truthing data to evaluate the classification accuracy. Existing global, regional and local studies were also considered for validation. The results show an overall accuracy of 77%, with the producer's accuracy being 78% and user's accuracy 83%. The Kappa coefficient (0.73) shows moderate agreement between on ground and satellite derived map. This is deemed sufficient for supporting water management analysis. The availability of major crop rotation statistics and types of forests and savanna is key information for the input data in hydrological models and water accounting frameworks.