中国规模生猪养殖效率测度及其补贴政策效益评价研究

利用曼奎斯特指数和倍差法分析中国2001—2016年生猪补贴政策实施前后的生猪养殖效率,旨在科学地对中国生猪补贴政策效益进行评价。结果表明,在该时间段,中国大规模和中规模生猪养殖的规模效率总体上略有增长,技术效率和纯技术效率下降明显;生猪养殖规模不同,其全要素生产效率变化也有所差异;大、中规模生猪养殖的技术效率变化指数波动幅度并不大,但是全要素生产率和技术进步变化指数波动幅度大,且两者都呈现出同步变化趋势;生猪补贴政策整体上降低了生猪养殖的规模化效率。进一步研究发现,饲料等要素投入的多少对不同规模生猪养殖的规模效率影响差异显著,表现为投入越多,生猪养殖规模效率越大。地域GDP越高,大规模和中规模生猪的养殖规模效率也会越大,而且生猪调出大县奖励和畜牧标准化养殖补贴政策降低了大规模和中规模生猪养殖的规模效率。由此可知,中国生猪养殖规模效率的提升并不能过多地依赖于生猪补贴政策,而应该更多地从根本上提高养殖技术。     

黑龙江垦区农业生产效率及其影响因素研究

文章以黑龙江垦区农业生产效率为研究对象,通过SBM方向性距离函数测算1994～2017年垦区整体、各管理局静态层面农业技术效率,利用Luenberger生产率指标进一步测算动态层面全要素生产率。运用可行广义最小二乘法分析垦区农业生产效率影响因素。结果表明,1994～2017年垦区整体层面农业全要素生产率实现增长。科技创新对农业生产效率表现为正向影响,但影响不显著,基础设施建设和市场化水平对农业生产效率有显著正向影响。垦区当前人力资本水平、农业生产性服务、对外开放水平、经济发展水平和受灾率对农业生产效率均表现为显著负向影响。     

农村互联网发展对中国玉米全要素生产率的影响

采用DEA-mamlquist指数测算2004—2019年中国17个玉米主产省(区)的全要素生产率,运用联立方程组模型实证检验农村互联网发展对玉米全要素生产率的影响及其作用机理,并分区域探讨其差异性。结果显示:2004—2019年中国玉米全要素生产率年均增长0.2%,主要依靠技术进步的单轨模式驱动。农村互联网的发展显著(P<0.01)提升玉米全要素生产率,主要依靠技术进步和技术效率的协同作用驱动。分区域来看,农村互联网发展对玉米全要素生产率均具有显著(P<0.01)的促进作用,其影响程度由高到低依次为北方春播玉米区>黄淮海平原夏播玉米区>西北灌溉玉米区>西南山地玉米区。建议进一步提高农村互联网的配套设施建设,发挥互联网“连接经济”的优势,应用多元化互联网技术,促进不同生态类型区玉米生产效率的提升。     

蔬菜洪涝灾后田间管理主要技术措施及对策

持续大到暴雨导致蔬菜田块遭受水淹,易造成涝灾、渍害,田间湿度大,病害多发,落花、落果较多,出现沤根、烂根、死棵、绝收现象。为搞好生产救灾,将灾害损失降至最低,针对洪涝灾害影响、灾后田间管理、灾后恢复生产等方面阐述了蔬菜灾后生产技术措施,对不同受灾程度的田块提出了清沟沥水、及时追肥、抢收抢种和加强病虫害防治等田间管理技术对策。     

农机作业服务能提升小麦生产技术效率吗?——基于2007—2017年省级面板数据的实证分析

为了解农机作业服务的作用效果，基于中国15 个小麦主产省(自治区)2007—2017年面板数据，采用随机前沿生产函数对小麦生产技术效率进行估算，并运用Tobit模型分析影响小麦生产技术效率的因素，研究农机服务对技术效率的影响并解释其作用机制。结果表明:2007—2017年小麦生产技术效率逐年递增，各省间存在显著差异，且起点低的省份技术效率增长速度明显快于领先的省份，区域间不平衡逐步缩小；农机投入对小麦技术效率有显著正向影响，主要通过替代效应、技术效应及分工效应等路径优化小麦生产要素配置，获得小麦技术效率的提高。基于研究结论，提出建议如下:规范农机服务市场，健全农机社会化服务体系；优化农机补偿机制，提升政策作用的时效性。     

生态放养鸡饲养管理技术

我国农业经济快速发展,养殖工作的重要性变得更为突出,其中以生态放养鸡的饲养管理工作最为重要。但是在生态放养鸡的饲养管理工作开展过程中,却发现存在一定的问题,这些问题来自于人为及自然等2个方面,导致生态放养鸡的饲养管理技术没有从根本上得到最大程度的提升。养殖者应对生态放养鸡饲养管理工作的开展予以全面化重视,只有确保相关的技术要点得到实现,才能提升生态鸡的养殖水平。     

奶牛人工授精的优缺点和技术要点

奶牛人工授精技术加速了奶牛品种改良进程,实现了将优秀种公牛精液跨区域、超时限的利用共享,极大地促进了养牛业的发展。以奶牛人工授精应用现状为出发点,介绍了人工授精技术的优点和不足,最后结合自身工作经验,从发情鉴定、适时配种、精液解冻、精液检测、输精、精液保存和妊娠检测等技术要点进行概述,以期更好地促进奶牛人工授精技术的应用。     

Technical efficiency of different farm sizes for tilapia farming in China

China is the world's largest tilapia producer. This study uses the stochastic frontier function in the Cobb–Douglas model to evaluate a production frontier for tilapia aquaculture and analyses the relationship between farm size and production efficiency in China. A random sample of 300 tilapia farmers was surveyed in the main tilapia‐producing areas to study their economic efficiencies. The percentage distribution of tilapia farm technical efficiency was determined, with an average efficiency of 79%, which showed that the sample tilapia farmers operate at 21% below the production frontier and hence that they still have a chance to achieve targeted yields. The technical efficiencies of two categories (≤1 ha and >1 ha) were 78.82% and 79.27% respectively. A second‐stage analysis investigated the relationship between farm size and technical efficiency and showed a positive relationship between farm size and production efficiency based on the ordinary least‐squares model. The optimal farm size was found to be 7.50 ha. This study proposes strategies such as enlarging the farming scale moderately, thereby achieving the advantage of economies of scale, and enhancing the competitiveness of the tilapia industry in China.     

马铃薯种植栽培管理技术要点研究

在粮食作物中，马铃薯属于关键，诸多国家都是马铃薯产国，我国马铃薯种植栽培面积也十 分广泛，所以，需要针对于马铃薯特征全面普及其种植与栽培技术，以此来保障马铃薯总产量。     

Ecoviability for ecosystem‐based fisheries management

Reconciling food security, economic development and biodiversity conservation is a key challenge, especially in the face of the demographic transition characterizing many countries in the world. Fisheries and marine ecosystems constitute a difficult application of this bio‐economic challenge. Many experts and scientists advocate an ecosystem approach to manage marine socio‐ecosystems for their sustainability and resilience. However, the ways by which to operationalize ecosystem‐based fisheries management (EBFM) remain poorly specified. We propose a specific methodological framework—viability modelling—to do so. We show how viability modelling can be applied using four contrasted case‐studies: two small‐scale fisheries in South America and Pacific and two larger‐scale fisheries in Europe and Australia. The four fisheries are analysed using the same modelling framework, structured around a set of common methods, indicators and scenarios. The calibrated models are dynamic, multispecies and multifleet and account for various sources of uncertainty. A multicriteria evaluation is used to assess the scenarios’ outcomes over a long time horizon with different constraints based on ecological, social and economic reference points. Results show to what extent the bio‐economic and ecosystem risks associated with the adoption of status quo strategies are relatively high and challenge the implementation of EBFM. In contrast, strategies called ecoviability or co‐viability strategies, that aim at satisfying the viability constraints, reduce significantly these ecological and economic risks and promote EBFM. The gains associated with those ecoviability strategies, however, decrease with the intensity of regulations imposed on these fisheries.