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111.
The tidal river management (TRM) approach is an indigenous management practice in the Southwest part of the Ganges-Brahmaputra delta in Bangladesh. This approach has a high potential for extending area under agriculture with a positive impact on sustainable production and consequently on sustainable land use planning. Until recently, no studies provide a quantitative assessment on agricultural benefits of TRM operation. In this study, we aim to assess the benefits of TRM operation by using innovative approaches such as comparing land use change, agricultural production and economic cost-benefit analysis for two scenarios (with and without TRM) in the Hari-Teka-Bhadra catchment. We found that the financial benefit of TRM operation was 85.5 million US dollar per year from the agriculture sector. The results are useful for promoting land use policy through TRM approach in achieving greater sustainability in the area.  相似文献   
112.
[目的]甘蔗增产是在食糖消费持续增长趋势下,世界糖业市场稳定的重要原因。揭示甘蔗增产要素,不仅能为甘蔗生产市场监测提供必要的理论支撑,而且还可以发现资源环境约束下甘蔗可持续发展的路径选择。[方法]基于LMDI模型,文章从世界和国别两个视角,剖析世界甘蔗增产的主要贡献因素。[结果]1961—2014年世界甘蔗生产逐渐向优势区域集中,产量提升2倍,其中70%增产源于播种面积扩张,30%来自单产提升;面积扩张对多数国家甘蔗增产的贡献大于单产提高,中国甘蔗增产同样得力于面积扩张,但单产提升显著,贡献率高达34%,位居世界前列;甘蔗生产中的资源环境问题逐渐凸显,现有的甘蔗增产模式已给脆弱的生态环境造成了深远的负面影响。[结论]资源环境约束背景下,转变甘蔗增产模式迫在眉睫,必须加快由依赖面积扩张的粗放型增长模式向单产提升的集约型生产模式转变的步伐,方可实现中国乃至世界甘蔗糖业的可持续发展。  相似文献   
113.
[目的]为了解叶尔羌河平原绿洲耕地利用变化与粮食产量的耦合关系,以此优化粮食生产系统的指导方式,提高叶尔羌河平原绿洲粮食产量,协调叶尔羌河平原绿洲耕地利用转型与粮食产量的耦合关系,并为叶尔羌河平原绿洲的粮食安全保护提供一定的政策启示。[方法]文章运用熵值法,以粮食生产相关的“投入”指标为评价依据,耕地利用强度由地均化肥使用强度、有效灌溉比例、复种指数及地均农业机械化水平等4个指标构成,以及利用1990—2016年叶尔羌河平原绿洲粮食产量,分析其耕地利用转型和粮食产量耦合关系时空变化。[结果](1)1990—2016年叶尔羌河平原绿洲各县耕地利用强度不断增大,并且区域时空格局差异明显,研究初期东北部地区的耕地利用程度强于西部地区,而2016年呈现出西南—中东部强,东北部弱的态势; 从粮食产量方面来看,叶尔羌河平原绿洲粮食产量整体有所增长,空间分异特征较不明显;(2)耕地利用强度—粮食产量耦合类型时空演化特征明显,高耦合值区增加,低耦合区值逐年减少; 从空间上看,叶尔羌河平原绿洲西部地区耕地利用转型与粮食产量耦合度越来越高。(3)耕地利用转型推动粮食生产格局不断演化,叶尔羌河平原绿洲耕地利用转型与粮食产量耦合度在1990—2016年呈现耦合度逐渐增加的趋势,耕地利用转型对保障区域粮食安全具有重要作用。[结论]叶尔羌河平原绿洲粮食产量随着耕地利用转型的不断深入而不断提高,耕地利用转型对粮食安全具有有利影响。  相似文献   
114.
Using a quasi-natural experiment, this study examines the effects of margin trading and short selling on bond yield spread in China. It finds that both margin trading and short selling can reduce bond yield spread. Additionally, it finds that margin trading lowers firms’ debt ratios and increases their credit ratings, which explains the reduced spread. In other words, margin trading can impact investors’ decisions by revealing positive information about a firm. Another finding is that short selling lowers the bond yield spread by decreasing earnings management, suggesting that short selling has an impact on investors’ decisions through its effect on corporate governance. Our results suggest that margin trading transmits positive information and short selling impacts firms’ policies. These results provide support for future regulations of margin trading and short selling.  相似文献   
115.
Traditional carry trade strategies are based on differences in short-term interest rates, neglecting any other information embedded in yield curves. We derive return distributions of currency portfolios, where the signals to buy and sell currencies are based on summary measures of the yield curve. We find that a strategy based on the relative curvature factor, the curvy trade, yields higher Sharpe ratios and a smaller return skewness than traditional carry strategies. Curvy trades build less upon the typical carry currencies and are hence less susceptible to crash risk. In line with that, standard pricing factors of traditional carry returns fail to explain curvy trade returns.  相似文献   
116.
The public yield spreads of bonds vary widely between Chinese provinces/municipalities, with the average for the highest province double that of the lowest one. Although we find that these patterns are mainly attributable to economic and legal conditions, locational effects like geographic distance and public firm credit ratings also appear to be contributory. We show that these effects are induced by different regional informational environments and are robust to controlling for potential endogenous location choices.  相似文献   
117.
118.
This study examines the impact of mandatory International Financial Reporting Standards (IFRS) on the market quality of the Australian Securities Exchange (ASX) 200 constituent stocks. Using traditional metrics that are consistent with prior literature (i.e., bid‐ask spreads), the first stage analysis confirms that stock liquidity has improved. However, when the analysis is extended to consider the trading costs incurred by market participants (i.e., execution shortfall), results suggest liquidity has not changed significantly. The paper utilizes rich unique datasets that contain detailed trade information, and findings are robust after controlling for trade difficulty and market conditions. In the era of High Frequency Trading (HFT) and occurrences of ‘fleeting’ liquidity, this paper provides some evidence that while IFRS may have enhanced ‘visible’ bid‐ask spreads, tangible liquidity for market participants, particularly global institutional investors, has not improved significantly.  相似文献   
119.
120.
Industrial mining generally develops in rural areas where agriculture is the main subsistence activity of the population. However, there seems to be an incompatible coexistence between agricultural and mining activities, as both require a large amount of land. Given the extensive agricultural system in Burkina Faso and the expansion of mining since 2007, this study analyzed the effect of industrial mining land use on poverty in the 13 regions of Burkina Faso. The study examined the effect of mining land use intensity on cereal production/yield before exploring its impact on poverty by using several econometric methods and various data from the National Statistics Institute. The results indicate that mining land use intensity had no direct effect on poverty; instead, the effect is indirect. Indeed, mining land use intensity negatively affects cereal yield, and that reinforces the incidence of poverty in mining regions. Moreover, the results show that cereal production increases with cropped land. As cereal yield decreases with industrial mining land use intensity, this suggests that the expansion of mining would contribute to the jeopardizing of the food supply as well as the exacerbation of poverty in mining regions. Therefore, policies are needed to encourage the sustainable management of land and mining revenue redistribution in the mining regions of Burkina Faso.  相似文献   
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