中国耕地资源流失的深层原因及对策

我国是一个人多地少，且农业人口占70％的国家，保护和利用好在相当长的时期内都难以替代的耕地资源意义十分重大。该文分析了我国耕地资源流失的基本状况，分别从农地产权制度、征地制度、管理体制、农村土地市场等方面揭示了耕地大量流失的深层原因，提出了相应的对策措施与政策建议。     

北京都市型现代农业的定位与优势条件的耦合分析

从背景、目标方面确定了北京都市型农业的定位，明确了发展都市型农业的优势条件。并从可以更好地实现首都的整体功能，有效地落实统筹城乡经济社会发展战略，更大程度上满足城市居民消费需求。更好地解决农民增收和山区资源发展等方面进行了分析。     

Dynamics of Agricultural Technology Adoption: Age Structure, Reversibility, and Uncertainty

We develop a dynamic model of technology adoption that generalizes previous literature by incorporating technology age, reversible investment, variable inputs and outputs, and stochastic prices. The model is calibrated for irrigated cotton production in California. Optimal investment exhibits a significant vintage capital effect which provides a new candidate explanation for delayed technology diffusion. We show that the hurdle rate derived by option value models can be partially explained by the assumption of irreversible investment, and simulations demonstrate this assumption has regional policy relevance. Uncertainty affects optimal investment but has a declining effect with technology age.     

基于“藏粮于技”的粮食生产实施策略

粮食安全关乎民生和国家安全,"藏粮于地,藏粮于技"是维护我国粮食安全的基本战略。其中"藏粮于技"必须通过科技创新解决当前农业生产中的难题,提高粮食生产领域的科技贡献率。同时,必须前瞻性地加速数字农业建设、精准农业实践和智慧农业探索,奠定我国粮食生产领域生态智慧农业的基础。     

黑龙江省两大平原现代农业经营主体发展研究

黑龙江省两大平原是国务院建立全国首个现代农业综合配套改革试验区,以此为契机发展现代农业,能充分利用试验区内耕地资源富饶、国家政策支持、科技水平较高及农垦系统示范等优势。文章通过把握现代农业发展的内在规律,将现代农业经营主体的发展按组织属性分为大型企业运作型经营主体、龙头企业带动型经营主体、合作经营型经营主体、家庭农场型经营主体等4种类型。通过海亮有机畜牧养殖公司、望奎县北极雪速冻食品有限公司、呼兰区大用现代农业农机专业合作社、绥棱大力家庭农场等案例,从实证的角度分析现代农业经营主体的发展定位与产业效应。并指出发展现代农业经营主体现存的制约因素与约束条件,提出相应的对策建议,进而促进两大平原土地流转制度创新、农业结构调整、高效农业产业体系构建,以期为农业生产力快速提升,农业增产、农民增收,切实带动黑龙江省现代农业的发展提供参考借鉴。     

加快发展农业特色产业的启示与思考——基于礼县苹果产业的调研

文章以礼县苹果产业的发展为例,阐述了礼县立足县情,充分利用自然资源优势,选择发展苹果产业作为当地发展经济,实现农民增收、农业增效,探索形成一条富民强县的产业之路中取得的成效及存在的问题,并提出对策和建议。该文主要采用对比的方法,使用礼县苹果产业发展的具体数据,论述了农业特色产业对促进农民的脱贫致富、激发了农村生机和活力、夯实农业可持续发展基础发挥的重要作用,同时以礼县苹果产业为例,探讨分析了在不发达地区,农业特色产业存在区域化发展不平衡、生产综合优势不突出,品牌培育意识不高、营销成效不显著,生产管理水平较低、产品效益有待提高,产区内劳动力不足、产业发展急需提升等一些共性问题,并从政府统筹规划、品牌建设、品种改良和生产技术培训、培育壮大龙头企业等角度提出促进农业特色产业健康发展的对策和建议,为中西部地区农业特色产业的发展提供借鉴和参考。     

Productivity and farm size in Australian agriculture: reinvestigating the returns to scale

A positive relationship between farm size and farm productivity is often considered to be largely due to increasing returns to scale in farm production. However, using farm‐level data for the Australian broadacre industry, we found that constant or mildly decreasing returns to scale is the more typical scenario. In this study, the marginal returns to various farm inputs are compared across farms with different sizes. We found that large farms achieved higher productivity by changing production technology rather than increasing scale alone. The results highlight the disparity between ‘returns to scale’ and ‘returns to size’ in the industry, suggesting that productivity improvement among smaller farms can be made through increasing their ability to access advanced technologies, rather than simply expanding their scale.     

Climate Smart Agriculture? Assessing the Adaptation Implications in Zambia

We examine a set of potentially climate smart agricultural practices, including reduced tillage, crop rotation and legume intercropping, combined with the use of improved seeds and inorganic fertiliser, for their effects on maize yields in Zambia. We use panel data from the Rural Incomes and Livelihoods Surveys merged with a novel set of climatic variables based on geo‐referenced historical rainfall and temperature data to explore the changing effects of these practices with climatic conditions. We estimate the impacts on maize yields, and also on the exhibition of very low yields and yield shortfalls from average levels, as indicators of resilience, while controlling for household characteristics. We find that minimum soil disturbance and crop rotation have no significant impact on these yield outcomes, but that legume intercropping significantly increases yields and reduces the probability of low yields even under critical weather stress during the growing season. We also find that the average positive impacts of modern input use (seeds and fertilisers) are significantly conditioned by climatic variables. Timely access to fertiliser emerges as one of the most robust determinants of yields and their resilience. These results have policy implications for targeted interventions to improve the productivity and the resilience of smallholder agriculture in Zambia in the face of climate change.     

汉代辽东犁和其作亩法

本文通过考察东北农业的实体，分析了它的力量源泉。根据《齐民要术》中登场的“辽东犁”，研究古代中国东北地区的耕作方式和作亩法，来看末冷地带东北农业的本质。东北地区的农耕是在农业的原始基础上吸收了游牧民的畜牧技术和中原度韩半岛的农业文化。这种特征在耕作方式上可见一斑，即使用了辽东犁的作亩法。     

天津市农业比较优势分析及结构调整研究

针对我国加入WTO和新时期天津市农业结构调整的需要，采用规模优势指数、效率效益优势指数、综合比较优势指数的计算方法，对天津市农业及主要农产品进行比较优势分析，根据分析的结果，提出了天津市农业及主要农产品结构调整的建议。