基于CiteSpace的中国草地流转研究文献计量分析

目的 文章基于文献计量总结和归纳中国草地流转的研究热点、内容、演进以及今后研究的趋势和方向。方法 CiteSpace文献可视化分析与文献计量分析方法。结果 （1）草地流转发文数量总体呈增加趋势,根据发文数量变动轨迹,可划分为缓慢增长期（1997—2003年）、快速上升期（2004—2009年）和波动增长期（2010年至今）3个阶段。（2）作者与发文机构中,中国草地流转研究主力队伍初步形成,作者之间的合作关系主要在团队内部,而团队之间的合作关系较弱。（3）研究热点集中于内蒙古牧区牧户的草地流转行为方面。时间维度上,第一阶段（1997—2004年）聚焦于草地流转内涵及制度;第二阶段（2005—2015年）以“草地流转影响因素”为核心议题;第三阶段（2016年至今）以研究草地流转的生态效应为主。研究内容上,主要包括草地流转特征及原因、草地流转的影响因素分析、草地流转综合效应研究等三方面。结论 草地流转研究从简单的定性描述到深入探讨影响机理研究,均有所突破。今后,草地流转研究应重点关注草地流转的生态效应。     

城乡建设用地指标纵向配置逻辑与执行偏差研究

研究目的：从中央—省—市三层级政府的关系切入，分析中央到省、省到市的纵向指标配置逻辑对指标执行偏差的影响，以期为国土空间规划的指标配置与执行提供参考。研究方法：多元线性回归分析法、面板数据回归分析法。研究结果：（1）中央基于区域均衡偏好往省的指标配置对省级执行偏差的影响没有得到证据支持；（2）省往市的策略性分配能够减轻省级执行偏差，但与经济体量不相符的指标错配会加剧市级执行偏差；（3）省级政府在央地关系中起到承上启下的中间政府作用，中央的指标配置能通过省级的策略性分配来减轻偏差，但省级的指标配置则面临着更少的容错空间。研究结论：在国土空间规划的指标配置与执行过程中，应强化省级政府基于本地信息优势的策略性分配能力，加强指标配置的科学性，此外，应进一步向省分权并制度化，在推动指标高效利用的同时维护中央政策的权威性。     

Domestic and trade impacts of foot‐and‐mouth disease on the Australian beef industry

Australia is the sixth largest producer of beef and the second largest exporter of beef. Average beef exports from Australia are approximately 65 per cent of the total amount of beef produced, about 1.3 million tonnes. Australia is particularly vulnerable to diseases that are not endemic to the country and could close or disrupt its export markets for beef. In this study, we construct a bioeconomic optimisation model of the Australian beef industry that captures production and consumption decisions, domestically and internationally, and the impacts on the beef industry of a potentially catastrophic disease, foot‐and‐mouth disease (FMD). This study analyses localised to large‐scale outbreaks and suggests that changes in economic surplus because of FMD range from a positive net gain of $57 million to a net loss of $1.7 billion, with impacts on producers and consumers varying depending on the location of the outbreak, control levels and the nature of any trade ban.     

基于灰色系统理论的山东省海洋生物医药业发展分析

发展海洋生物医药业是山东省建设蓝色经济区,大力发展海洋高端产业,加快实现海洋经济结构优化升级的重要途径。论文运用灰色关联模型,定量分析山东省海洋生物医药业各影响因子的贡献度,研究发现,海洋科研机构科研经费总收入、政府资金、发明专利数和山东省海洋生产总值对山东省海洋医药业增加值的影响最大。建立灰色预测模型,对山东省海洋生物医药业发展趋势进行分析,研究发现在有效的政策环境下,产业能够保持继续壮大的态势。本文据此,提出提升产业竞争力、促进产业可持续发展的政策建议。     

超声波辅助提取黑豆油及其脂肪酸组成分析

采用超声波辅助法,以石油醚为溶剂提取黑豆油。考察了提取时间、提取温度、料液比和超声波功率对黑豆油提取效果的影响。结果表明,提取黑豆油的优化工艺条件为：提取时间9rain,提取温度58℃,料液比1：9,超声功率110W,在此条件下,黑豆油得率达到83．83％。对黑豆油进行GC—MS分析可知,黑豆油的主要脂肪酸有棕榈酸19．24％、亚油酸46．28％、油酸18．62％和硬脂酸7．3％等,其不饱和脂肪酸含量达68．98％。     

Adoption of weather‐index insurance: learning from willingness to pay among a panel of households in rural Ethiopia

In this article we examine which farmers would be early entrants into weather‐index insurance markets in Ethiopia, were such markets to develop on a large scale. We do this by examining the determinants of willingness to pay for weather insurance among 1,400 Ethiopian households that have been tracked for 15 years as part of the Ethiopian Rural household Survey. This provides both historical and current information with which to assess the determinants of demand. We find that educated, wealthier individuals are more likely to purchase insurance. Risk aversion is associated with low insurance take‐up suggesting that models of technology adoption can inform the purchase and spread of weather index insurance. We also assess how willingness to pay varied as two key characteristics of the contract were varied and found that basis risk reduces demand for insurance particularly when the price of the contract is high, and that provision of insurance through groups is preferred by female headed households and individuals with lower levels of education.     

Impacts of the End of the Coffee Export Quota System on International‐to‐Retail Price Transmission

We examine the impact of the end of the coffee export quota system (EQS) on international‐to‐retail price transmission in France, Germany and the United States. We take account of the existence of long‐run threshold effects and short‐run price transmission asymmetries (PTAs). We find evidence of threshold effects in both periods (EQS and post‐EQS) in all three countries and the presence of short‐run PTAs during the post‐EQS period in all countries, but not during the EQS period. Our results indicate that the threshold values are smaller in the post‐EQS period, suggesting that retail prices became more responsive to changes in international prices. However, the speed of adjustment towards the long‐run equilibrium decreases during the post‐EQS period in the three countries. In the short run, non‐linear impulse response analyses indicate that a shock in international prices was more persistent during the EQS period than in the post‐EQS period. Moreover, we find evidence of short‐run PTAs in the post‐EQS period, with differences across countries. We find support for the ‘rockets and feathers’ principle in the United States; in contrast, retail prices respond faster when international prices are falling in Germany and France. We explain these differences in terms of market structures.     

Determinants of herbicide use in rice production in the Philippines

This study identifies farm‐specific and market factors affecting the adoption of herbicides and the level of herbicide use by rice farmers in the Philippines. This requires the application of a modified version of Heckman's two‐step method to estimate a random‐effects double‐hurdle model for unbalanced panel data. The age of the farmer, household size, and irrigation use are significant determinants of the decision of farmers to adopt herbicides as an alternative to manual weeding, while economic variables such as the price of herbicides, total income, and access to credit determine the level of herbicide use. Determinants of both adoption and level are land ownership, farm area, and the method of crop establishment. These results are potentially relevant when designing policies to reduce excessive herbicide use or to encourage the adoption of alternative weed control methods such as integrated weed management.     

Chili Growers' Experience with Contract Farming in Malaysia

The objectives of the study were (a) to examine the perception of chili growers toward contract farming (CF) and (b) to ascertain the factors that motivate the growers to participate in CF. A total of 190 chili growers within East Coast Economic Region (ECER) were interviewed. The data were analyzed using SPSS to describe the respondents' profile and CF practices. At the present moment, the chili growers have a contract agreement with the Farmers' Organization Authority of Malaysia (FOAM) and FOAM, in turn, has a contract agreement with Nestle. Factor analysis was carried out to identify latent factors that influenced chili growers in their participation in CF. These factors are extension services, access to new markets, market assurance, protection for growers, skills transfer, and indirect benefits.