灌溉耕地空间分布制图研究进展

[目的]灌溉耕地空间分布是管理水资源、指导农业生产和监控环境变化的基础数据,遥感是获取灌溉耕地空间分布的重要手段。科学总结有关区域灌溉耕地空间分布制图的研究进展,可为遥感在该领域的应用研究提供参考。[方法]文章全面收集近年来国内外利用遥感提取灌溉耕地的文献资料,系统分析了灌溉耕地制图的特征选择和主要技术方法,并展望了未来的发展方向。[结果]从分类特征的角度看,气候、生产方式和设施等农业相关地域条件是灌溉耕地制图的必要参考;灌溉引起的水分或植被生长状况差异是主要依据;引入参量的时序变化特征或新的特征参量是对单一影像信息不完善的有效补充。从分类方法的角度看,不同分类方法多局限于局地或区域尺度,规则普适性不高,真值数据收集困难,难以适应大尺度下多样的地域条件,导致无法高效及时地生产更新相应规模且合适分辨率的产品,大区域灌溉制图的主要方式仍依赖空间分配模型。[结论]未来发展而言,自动分类技术和遥感影像资源的丰富已为高效生产灌溉分布地图提供了基础条件,整合数据资源、挖掘特征参量和优化分类方法等3个方面应是未来的主要发展方向。     

Determinants of workers’ remittances: An empirical investigation for a panel of eleven developing Asian economies

We explore the key motives of migrant workers’ remittances from abroad for 11 major Asian migrant‐sending countries. Using panel regressions, we find that relative higher growth rate, interest rate and capital market returns of home over the host, investment, financial deepening at home have significant impact on remittance inflows into Asia, along with higher per capita incomes and international crude oil prices. With incorporation of per capita incomes and lagged impact of remittances, we observe an emergence of consumption motives to remit. Therefore, we conclude that both investment and altruistic motives are the driving forces for remittances inflows into the Asian economies.     

武汉老橱窗特征解析

武汉老橱窗是当时社会生活的缩影：老橱窗是经济大潮起落的风向标,是政治风云变幻的晴雨表,是都市生活的流行时尚眼,是商店卖场的无声宣传员,是艺术空间的多彩百花园。     

Shifting patterns of oil palm driven deforestation in Indonesia and implications for zero-deforestation commitments

Oil palm plantations in Indonesia have been linked to substantial deforestation in the 1990s and 2000s, though recent studies suggest that new plantations are increasingly developed on non-forest land. Without nationwide data to establish recent baseline trends, the impact of commitments to eliminate deforestation from palm oil supply chains could therefore be overestimated. We examine the area and proportion of plantations replacing forests across Sumatra, Kalimantan, and Papua up to 2015, and map biophysically suitable areas for future deforestation-free expansion. We created new maps of oil palm plantations for the years 1995, 2000, 2005, 2010 and 2015, and examined land cover replaced in each period. Nationwide, oil palm plantation expansion occurred at an average rate of 450,000 ha yr⁻¹, and resulted in an average of 117,000 ha yr⁻¹ of deforestation, during 1995–2015. Our analysis of the most recent five-year period (2010–2015) shows that the rate of deforestation due to new plantations has remained relatively stable since 2005, despite large increases in the extent of plantations. As a result, the proportion of plantations replacing forests decreased from 54% during 1995–2000, to 18% during 2010–2015. In addition, we estimate there are 30.2 million hectares of non-forest land nationwide which meet biophysical suitability criteria for oil palm cultivation. Our findings suggest that recent zero-deforestation commitments may not have a large impact on deforestation in Sumatra, where plantations have increasingly expanded onto non-forest land over the past twenty years, and which hosts large potentially suitable areas for future deforestation-free expansion. On the other hand, these pledges could have more influence in Kalimantan, where oil palm driven deforestation increased over our study period, and in Papua, a new frontier of expansion with substantial remaining forest cover.     

How do great shocks influence the correlation between oil and international stock markets?

We investigate the impacts of great shocks (2003 Iraq War and 2008 Financial Crisis) on the correlations between oil and US/China stock markets, utilizing a novel MADCC (mixed asymmetry dynamic conditional correlation) model. This model successfully captures the coexistence of opposite signed asymmetries. We find that great shocks indeed increased the correlations. Further, results from the news impact surfaces indicate that correlations between oil and stock markets are higher to joint negative shocks; however, correlation between stock markets has stronger response to joint positive shocks.     

Quantile serial dependence in crude oil markets: evidence from improved quantilogram analysis with quantile wild bootstrapping

We examine the quantile serial dependence in crude oil prices based on the Linton and Whang’s quantile-based portmanteau test which we improved by means of quantile wild bootstrapping (QWB). Through Monte Carlo simulation, we find that the quantile wild bootstrap-based portmanteau test performs better than the bound testing procedure suggested by Linton and Whang. We apply the improved test to examine the efficiency of two crude oil markets – WTI and Brent. We also examine if the dependence is stable via rolling sample tests. Our results show that both WTI and Brent are serially dependent in all, except the median quantiles. These findings suggest that it may be misleading to examine the efficiency of crude oil markets in terms of mean (or median) returns only. These crude oil markets are relatively more serially dependent in non-median ranges.     

GDP growth in Russia: different capital stock series and the terms of trade

There are different academic assessments of the principal forces behind Russia’s GDP growth. Studies that reconstruct capital stocks using gross fixed capital formation and the perpetual inventory method find that total factor productivity growth has been paramount to GDP growth. On the other hand, capital services datasets that have recently been made available find that capital developments have been instrumental in driving economic growth. We reconstruct a capital stock series for Russia for 1995–2013 and compare the results to two capital services time series using the Solow growth model. We also take into account terms of trade developments that have lent strong support to Russia’s economy. The terms of trade is shown to have been an important factor behind the development of gross fixed capital formation and thus GDP growth.     

The Success Factors of Food Events: The Case Study of Umbrian Extra Virgin Olive Oil

Gastronomic events are an important part of the “Made in Italy” and a vital tool for rural development. The aim of the study is to identify the complexity of the factors that determine the success of a food event. The authors, after state-of-the-art analysis of the event marketing, formulate the hypothesis of a causal model and form a data collection during the “open oil mills” in the Umbria region. Through in-depth interviews the participants were asked to express themselves about the importance and interest attributed to some aspects directly related to the theme of the event, and finally to indicate the degree of satisfaction and the likelihood of some of their future behavior. Statistical analysis based on structural equation models allowed the authors to highlight which aspects are significant in order to confirm the assumptions made. Results provide guidance for management decisions and organization of food and wine.     

Nothing Tastes as Local: Jordanians’ Perceptions of Buying Domestic Olive Oil

To date, little is known about how consumers perceive local and foreign olive oil. This study was conducted with the intention of exploring key trends in Jordanian consumers’ perceptions toward local olive oil and to examine whether they are ethnocentric toward purchasing their local olive oil in the era of the Arab Spring. The research design is a combination of quantitative with a qualitative technique to support and expand on the research findings. Data were collected from a total number of 196 Jordanians who live in Amman city. The results revealed that Jordanians are loyal to their country’s olive oil; they expressed strong ethnocentric tendencies toward purchasing it, and their purchasing tendencies are influenced by nationalism. Jordanians ranked their local olive oil as the best worldwide. This article provides original insights into the development and marketing strategies for local and global olive oil producers in the Jordan market and other Arab country markets.     

国际油价冲击与中国的经济增长——基于非对称关系视角的分析

本文基于季度数据，引入非对称协整模型，考察国际油价与中国经济增长的动态关系，并鉴于油价波动对不发达经济体可能的冲击，还测度了油价的不确定性并探析其对经济增长的影响，结果表明：（1）从短期来看，国际油价变化是国内经济增长的单向Granger原因，“中国因素”对全球油价变化的影响尚不明显；（2）从长期来看，国际油价和经济增长具有非对称协整关系，油价上涨对经济的影响明显大于油价下跌所产生的效应；（3）国际石油市场存在正反馈交易行为，导致油价波动在油价上涨时表现更加明显。油价不确定性在短期内对经济增长存在负面影响，长期中则不会显著影响经济增长。以上结果意味着必须高度重视石油安全问题，加强油价波动预警与风险管理系统。