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[学术文献 ] 基于重心模型的中国粮食生产与加工时空耦合分析 进入全文
中国知网
保障粮食安全从抓粮食生产向抓粮食产业转型升级转变，将粮食产业增值收益和粮食产业主体留在产区，是提高产区种粮积极性的有效手段。采用重心模型，从全国层面分析2017—2020年粮食生产重心与加工重心的演变趋势、时空耦合程度，评价我国粮食生产和加工耦合协调水平的空间格局。结果表明：我国粮食生产集聚重心迁移方向整体向北偏西迁移，粮食加工集聚重心整体向北偏东迁移，粮食生产和加工的重心总体向北迁移，具有变动一致性，粮食加工集聚重心迁移距离要高于粮食生产集聚重心迁移距离。粮食生产与加工集聚重心的空间距离在逐年减小，粮食产加空间耦合性越来越好。产粮大省要发挥粮食生产优势，挖掘粮食加工产业发展潜力。
[学术文献 ] 粮食安全视域下土壤健康培育的现实价值、主要挑战与有效路径 进入全文
中国知网
在强化耕地数量质量生态“三位一体”保护的新形势下， 土壤健康培育是全方位夯实国家粮食安全根基的必然举措。粮食安全视域下土壤健康培育是以提高土壤综合能力和多种功能价值为重点， 以系统化、绿色化、精准化为主要培育特征， 发挥政府、新型农业经营主体和小农户等各利益相关者的作用， 通过推广实施系列土壤健康培育措施， 促进农田生态、农业经济与社会效益有效协调。加快土壤健康培育具有贯彻落实国家战略、推动农业绿色发展、保障食品安全的现实价值。当前， 推动土壤健康培育存在土壤环境监测体系有待健全、生产者对土壤多功能性认识不足、农产品生产成本与价格双重压力抑制土壤健康培育、相关政策体系亟需健全、农作物种植结构与实施主体结构两方面均存在内部矛盾等主要挑战， 亟需抓住夯实培育基础、健全培育体制机制这一关键， 进一步深入推进绿色农田建设、建立健全土壤健康培育技术推广服务体系、促进土壤健康多元主体参与、完善土壤健康培育保障机制， 加快探索提升土壤健康培育的有效路径。
[学术文献 ] Africa pathway to food systems transformation: Challenges and opportunities 进入全文
IFPRI
This paper explores the pathways to transforming food systems in Africa, focusing on the challenges and opportunities that lie ahead. It examines the current state of food systems, highlighting issues such as food and nutrition security, environmental degradation, low agricultural productivity, limited availability and adoption of yield-increasing technologies, high malnutrition rates, violent conflicts and threats to peace and security, and inadequate governance. The paper emphasizes the need for policy reform, technological innovation, and capacity building to drive sustainable and inclusive food systems. Key drivers of change include policies promoting sustainable practices, increased funding for agricultural research, and improved market access through infrastructure development and trade policies. Good governance practices, including transparency, accountability, and inclusive decision-making, are crucial for effective policy implementation and stakeholder collaboration. Recommendations include empowering women and youth, supporting community-led initiatives, and leveraging the African Continental Free Trade Area (AfCFTA) to enhance intraAfrican trade. By adopting these strategies, Africa can build resilient, equitable, and sustainable food systems.
[学术文献 ] 保障水与粮食安全的国际农业用水管理先进技术与经验 进入全文
中国知网
水与粮食安全是世界各国和相关国际组织持续关注的议题。受人口增长、耕地条件、水资源约束及气候变化影响，粮食安全问题需要通过持续改善提升现有灌排工程设施，发展新的灌排工程设施，应用先进管理技术和措施，以及改革管理体制机制等综合措施来解决。灌排系统是一个包含农业生产、生态及水资源循环过程的大系统工程，其中灌溉和排水对生态环境影响日益受到关注。在开展农业节水的同时要关注节水的尺度效应，在提高灌区灌溉水利用率的同时，需综合考虑灌排系统的水循环过程和水资源整体利用效率、效益及对生态环境的影响。研究总结了国际上保障水与粮食安全的农业用水管理先进技术与经验，包括世界灌排发展现状与趋势、挑战、对策和创新，以及基于蒸散发管理的节水概念、技术和措施等内容。
[学术文献 ] Drying-wetting cycles affect soil structure by impacting soil aggregate transformations and soil organic carbon fractions 进入全文
sciencedirect
Drying-wetting (DW) cycles influence the formation and breakdown of soil aggregates and consequently impact the physical protection of soil organic carbon (SOC). However, the interaction between soil structural dynamics and SOC fraction changes driven by DW cycles is still unclear. Herein, aggregation pathways were tracked by using rare earth oxides (REOs) as tracers. The recombined soil columns were subjected to different DW frequencies (0, 1, 2, 4 and 8 cycles) and two DW intensities (low intensity, Q1; high intensity, Q2). During a 56-day incubation, aggregate distributions, mean water diameter (MWD), REO concentrations, the contents of SOC and its fractions (particulate organic carbon, POC; mineral-associated organic carbon, MOC) were measured. The results showed that MWD markedly increased with DW frequencies regardless of DW intensities and was significantly related to the relative changes of 2–0.25 mm aggregates (P < 0.05). Based on transformation paths, DW cycles stimulated the breakdown of > 0.25 mm aggregates and the aggregation of < 0.053 mm aggregates, thus leading to the increasing formation of 0.25–0.053 mm aggregates. Soil aggregate turnover time was affected by DW intensities and extended with DW frequencies (P < 0.05). Soil aggregate turnover time was displayed in the order of < 0.25 mm aggregates < 2–0.25 mm aggregates < 5–2 mm aggregates. MOC concentration exhibited an increasing trend with DW frequencies. A higher loss of SOC under high DW intensity resulted from more exposure of POC through soil aggregate breakdown. POC concentration was sensitive most to the 2–0.25 mm aggregates turnover time. The structural equation model (SEM) revealed that DW cycles exerted remarkable effects on MWD by impacting SOC fractions and soil aggregate transformations. Overall, our findings suggested that soil aggregate breakdown and formation processes, rather than aggregate size distributions, were more of a concern when evaluating the effects of DW cycles on soil structural stability.
[科技报告 ] Innovation for Sustainable Productivity Growth 进入全文
OECD
Total support to the agricultural sector across the 54 countries covered by this report averaged USD 842 billion per year during 2021-23. Many of the countries covered by the OECD Agricultural Policy Monitoring and Evaluation report provide support to their sectors, using policies that include market price support (tariffs and other border measures, MPS) that changes the price farmers receive for their products, or via various forms of budgetary transfers, such as output or input subsidies, payments for environmental services, or general services such as infrastructure development.
