The impact of conservation tillage on maize yield and input demand: the case of smallholder farmers in north‐west Ethiopia

This study analyses the economics of conservation tillage (CT) with respect to its effect on maize yield and chemical fertiliser, herbicide, and female and male labour demand. We estimate production and input demand functions using seemingly unrelated regressions on plot‐level cross‐sectional farm household data collected in the north‐west of Ethiopia. A two‐step control function is applied to address potential endogeneity bias due to the inclusion of the CT adoption decision as an explanatory variable. Our results show that CT increases maize yield and chemical fertiliser demand. Additionally, the results show that the adoption of CT reduces female and male labour required for crop production. However, this is achieved through the increased use of herbicides, which might have an undesirable health and environmental effects.     

The price of going green: the role of greenness in green bond markets

In this paper, we empirically investigate how greenness information is priced in the green bond market. Our comparison of liquidity-adjusted yield premiums of green bonds versus synthetic conventional bonds indicates that, on average, there is no robust and significant yield premium or discount on green bonds. However, green bonds certified by an external reviewer enjoy a discount of about 6 bps. Furthermore, green bonds that obtain a Climate Bonds Initiative certificate show a discount of around 15 bps. The findings suggest that a universally accepted greenness measure can benefit the development of the green bond market.     

Tidal river management for sustainable agriculture in the Ganges-Brahmaputra delta: Implication for land use policy

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.     

Return and volatility spillovers between currency and bond markets in India

This paper examines the return and volatility spillovers between the foreign exchange and bond markets of India using a bivariate asymmetric BEKK-GARCH (1,1) model for the period 4 April 2005 to 31 March 2017. We find the evidence of bidirectional return and volatility spillovers with asymmetric effects between these two markets. The spillovers are evidenced even during the periods when foreign portfolio investments in the Indian bond markets were relatively low suggests the existence of strong inter-linkages between both the markets.     

省域尺度下不同时序景观指数集与粒度效应分析

[目的]景观格局变化是景观生态学中的热点问题。研究省域尺度下不同时序景观指数的粒度效应、选取计算景观指数所需的适宜粒度范围并筛选出代表性景观指数集对分析景观格局变化具有重要意义。[方法]以安徽省土地覆被为研究对象,以2000年、2005年、2010年的Landsat TM遥感影像为主要数据源,采用土地利用转移矩阵对安徽省土地覆被的转移数量与方向进行研究;通过设置不同的栅格大小研究景观指数的粒度效应并选取合适的粒度范围;基于相关性分析、因子分析与敏感性分析,筛选出代表性景观指数集。[结果](1) 2000—2010年安徽省的土地覆被始终以耕地为主,其次是林地与人工表面;人工表面的增加是建立在耕地面积减少基础之上的,在10年间共有超过3 200km2的耕地转化为人工表面;(2)景观指数存在粒度效应,粒度变化会对景观指数的计算结果产生影响;省域尺度下计算景观指数所需的合适粒度范围为100～125m;(3)研究安徽省景观格局变化的代表性景观指数有4个,分别为最大斑块指数、景观形状指数、平均斑块面积、香农多样性指数。[结论]计算安徽省景观指数的适宜粒度范围为100～125m,安徽省的代表性景观指数集为最大斑块指数、景观形状指数、平均斑块面积、香农多样性指数,为进一步研究景观格局变化及驱动机制提供了依据。     

散粮筒仓系统消防应急灯具的选择

《消防应急照明和疏散指示系统技术标准》(GB 51309—2018)的实施,结束了消防应急照明不统一的乱象,在设计工作中得到广泛应用。本文针对散粮筒仓系统中消防应急灯具的选择进行了分析。     

秦迁陵县粮仓设置体系探讨--以出粮机构粮食来源问题为中心

除仓官外,秦迁陵县内的出粮机构还包括田官、离乡及司空等。它们并非都建有独立粮仓,所出粮食的来源也不尽一致。田官不设粮仓,它的出粮地是公共粮仓中的一间专属仓房。离乡建有供应该乡粮食开支的独立粮仓,且粮仓数量与该乡人口规模有关。小乡可能仅有一座粮仓,故有时会产生因储备不足而需要仓官额外输粮的问题。司空、发弩及■舍三者既未建有独立粮仓,也不如田官那般在公共粮仓内占有一间仓房,它们向外供应的粮食全都是由仓官转输。总之,秦迁陵县内设置的粮仓包括县级公共粮仓和离乡粮仓两类。田官、司空、发弩及舍虽承担了部分出粮职能,但并未给县内粮仓体系带来影响。     

Estimating yield curves of the U.S. Treasury securities: An interpolation approach

Following the approach of interpolation, this paper proposes the multiple exponential decay model to fit yield curves for both the U.S. TIPS market and the conventional Treasury security market. Several estimation methods, including the unconstrained/constrained nonlinear minimization, quadratic programming, and the iterative linear least squares, are applied to estimate the unknown parameters according to different curve‐fitting purposes. Comparisons between the proposed model and the alternatives show that the multiple exponential decay successfully (1) adapts to a variety of shapes associated with yield curves, (2) (partially) keeps in line with the economic interpretations of Nelson–Siegel summarized by Diebold and Li ( 2006 ), and (3) dominates the competing models in curve‐fitting performance measured by mean fitted‐price errors over the sample period. In addition, the exact specification of a nonparametric interpolation model is pinned down by applying three statistical tools, which enable us to jointly take into account validity, optimality, and parsimoniousness of the proposed model.     

乡村振兴战略下农村产业融合、人力资本与农民增收*——以浙江省为例

［目的］乡村振兴战略是贯彻新发展理念，建设现代化经济强国的重大战略之一。农村产业兴旺，农民生活富裕是乡村振兴战略的重要目标。农村一、二、三产业融合发展是实现乡村产业振兴，农民增收的重要途径。农村人力资本状况关系到农村产业融合的人才建设，关系到农民增收的实现。文章力图探究乡村振兴战略下农村产业融合、人力资本与农民增收间的相互作用关系，以期为乡村振兴战略的实现提供政策建议。［方法］以浙江省为例进行实证分析，通过建立PVAR模型，采用格兰杰因果关系及面板数据模型进行检验。［结果］农村产业融合及人力资本构成农民增收的格兰杰因果关系，两者都对农民增收产生显著影响，且人力资本影响效应更大。农民增收及人力资本对农村产业融合没有起到相应的促进作用。［结论］在实证分析的基础上，从加大人力资本投入、培育农村产业融合复合型人才及加强宣传引导工作等方面提出相应的政策建议促进农村产业融合。     

Impact of Donald Trump’s tariff increase against Chinese imports on global economy: Global Trade Analysis Project (GTAP) model

Donald Trump’s presidential campaign contains several trade protectionism plans. This paper aims to analyze possible global impact of United States’ plan to impose import tariff increase against China. The GTAP model is implemented. The simulations present possible short-run effects of full-protection and manufacturing-only protection with appropriate retaliation response from China. The policy might lead to GDP, terms-of-trade, and welfare decline in United States and China; and an increase in trade balance for United States. Trade diversion pattern is observed in the simulation results, predicting shrinking bilateral trade between the two countries and increasing export toward their third trading partners.