Will urban farming survive the growth of African cities: A case-study in Kampala (Uganda)?

Despite the fact that urban farming is widespread in many African cities there is not yet a clearly defined view on how to deal with these activities in urban planning and management. On the basis of field interviews in the rapidly expanding metropolitan area of Kampala (Uganda) three different urban farming types were identified: subsistence farming, garden farming and commercial farming. These three urban farming types have their own spatial organisation logic and each interact in a specific way with urban expansion. In this paper the possible outcome of three alternative urban management strategies for Kampala (urban sprawl, urban infilling and a combination of both) were translated into spatially explicit land use scenarios for the years 2020 and 2030. This allowed to evaluate the spatial impact of each scenario on the future viability of the different urban farming practices. Urban sprawl fragments large open spaces thereby reducing the space for subsistence farming with 80% by 2030. Urban infilling, on the other hand, decreases the opportunities for small to medium scale garden and commercial farming by a possible reduction of 62% of the available farming land by 2030. The results of the analysis are useful for urban planners as they give insight in the potential future effects of proposed planning strategies on urban farming.     

技术独董、经济政策不确定性与企业创新产出

创新产出是企业创新能力的直观体现,也是企业价值创造的源泉。以2008—2017年披露了专利授权信息的中国A股上市公司为样本,研究了独立董事技术专长对企业创新产出的影响。结果显示：（1）技术独立董事显著地促进了企业创新产出,且这种促进作用受到经济政策不确定性的负向调节;（2）技术独立董事是通过提高企业的创新投入来促进企业的创新产出的;（3）技术独立董事兼职席位与企业创新产出呈倒U型关系。根据上述研究结论,企业应当增加技术独立董事的引入并适当限制技术独立董事在其他企业兼职的行为,以充分发挥技术独立董事的创新驱动效应,提高企业创新产出。     

The impact of Chinese monetary policy shocks on East and South‐East Asia1

We study the effects of Chinese monetary policy shocks on China's major trading partners in East and South‐East Asia by estimating structural vector autoregressive (SVAR) models for six economies in the region. We find that a monetary expansion in Mainland China leads to an increase in real GDP (temporary) and the price level (permanent) in a number of economies in our sample, most notably in Hong Kong and the Philippines. The impact could result from intertemporal substitution present in a general equilibrium framework, which allows for positive domestic impacts of foreign monetary expansions. Our results emphasize the growing importance of China for its neighbouring economies and the significance of Chinese shocks for the design of monetary policy in Asian economies.     

Farmers’ risk preferences and their climate change adaptation strategies in the Yongqiao District,China

Farmers’ risk preferences play an important role in agricultural production decisions. This study characterizes risk preferences among farmers in Yongqiao and determines how these risk preferences are related to their choices regarding climate change adaptation strategies. We find that most farmers in the study area were aware of climate change. They were taking measures to protect their livelihoods against perceived changes to the local climate. The risk experiment result shows that the representative subject was risk averse, and women were more risk averse than men. The relationships between farmers’ risk preferences and different climate change adaptation choices were different. Farmers’ risk aversion was negatively and significantly related with adaptation strategies on planting new crop varieties and adopting new technology, but it had a significantly positive effect on purchasing weather index crop insurance. The results also indicate that the level of education, farming experience, farm size, household income and perception of climate change impacts influence farmers’ adaptation decisions.     

Intensity and spatial pattern of urban land changes in the megacities of Southeast Asia

Knowledge about intensity and spatial pattern of urban land changes (ULCs), i.e., changes from non-built-up to built-up lands, is important to a wide range of issues, from understanding of human–environment interactions and provision of urban ecosystem services, to land use policy development for landscape and urban planning toward sustainable urbanization. In this context, this paper aims to provide better understanding of the geospatial dimensions of the urbanization and landscape changes in two megacities of Southeast Asia. Specifically, we examine and compare the intensities and spatial patterns of ULCs in Metro Manila, Philippines and Bangkok Metropolitan Region (Bangkok MR), Thailand, during the 1990–2000 and 2000–2010 periods, using remote sensing and Geographic Information System (GIS) tools and techniques. In the measurement of ULC intensity, an intensity scale is proposed to determine whether the rate of ULC during a particular time interval, i.e., 1990–2000 or 2000–2010, relative to the uniform intensity that is based on the whole time extent, i.e., 1990–2010, is very slow, slow, medium slow/fast, fast and very fast. To characterize the spatial patterns of ULCs, the concepts of the diffusion-coalescence urban growth theory were applied. The results revealed that for Metro Manila, its ULC was more intense during the 1990s (fast) than in the 2000s (slow). For Bangkok MR, it was more intense during the 2000s (medium fast) than during the 1990s (medium slow). The results also revealed that Metro Manila has been in the process of coalescence, while Bangkok MR is still largely in the process of diffusion and expansion. In this paper, we also discuss some of the possible factors influencing ULC intensity trends and spatial patterns, the advantages of the methods used for ULC analysis and some land use policy-related development plans for the two megacities.     

Methodology to calculate the carbon footprint of household land use in the urban planning stage

The growing concerns of climate change require implementing measures to quantify, to monitor and to minimize greenhouse gas (GHG) emissions. Nonetheless, most of the measures available are not easy to define or execute because they rely on current emissions and have a corrective character. To address this issue, a methodology to characterize GHG emissions that allows implementing preventive measures is proposed in this paper. The methodology is related to household urban planning procedures and considers urban infrastructures to characterize GHG emissions and to execute preventive measures based on sustainability design criteria. The methodology has been tested by applying it to a set of medium-sized municipalities with average GHG emissions from 6,822.32 kgCO_2eq/year to 5,913.79 kgCO_2eq/year for every residential unit. The results indicate that the greatest pollutant source is transport, especially in the issuance of street network design, followed by gas and electricity consumption. The average undevelopable land area required for the complete GHG emissions capture amounts to 3.42 m² of undevelopable land for every m² of urbanizable land and 9.02 m² of undevelopable land for every m² of built land.     

Developing farm-specific marginal abatement cost curves: Cost-effective greenhouse gas mitigation opportunities in sheep farming systems

Growing demand for agricultural produce, coupled with ambitious targets for greenhouse gas emissions reduction present the scientific, policy and agricultural sectors with a substantial mitigation challenge. Identification and implementation of suitable mitigation measures is driven by both the measures’ effectiveness and cost of implementation. Marginal abatement cost curves (MACCs) provide a simple graphical representation of the abatement potential and cost-effectiveness of mitigation measures to aid policy decision-making. Accounting for heterogeneity in farm conditions and subsequent abatement potentials in mitigation policy is problematic, and may be aided by the development of tailored MACCs. Robust MACC development is currently lacking for mitigation measures appropriate to sheep systems. This study constructed farm-specific MACCs for a lowland, upland and hill sheep farm in the UK. The stand-alone mitigation potential of six measures was modelled, against real farm baselines, according to assumed impacts on emissions and productivity. The MACCs revealed the potential for negative cost emissions’ abatement in the sheep industry. Improving ewe nutrition to increase lamb survival offered considerable abatement potential at a negative cost to the farmers across all farms while, lambing as yearlings offered negative cost abatement potential on lowland and upland farms. The results broadly advocate maximising lamb output from existing inputs on all farm categories, and highlight the importance of productivity and efficiency as influential drivers of emissions abatement in the sector. The abatement potentials and marginal costs of other measures (e.g. reducing mineral fertiliser use and selecting pasture plants bred to minimise dietary nitrogen losses) varied between farms, and this heterogeneity was more frequently attributable to differences in individual farm management than land classification. This has important implications for the high level policy sector as no two farms are likely to benefit from a generic one size fits all approach to mitigation. The construction of further case-study farm MACCs under varying farm conditions is required to define the biophysical and management conditions that each measure is most suited to, generating a more tailored set of sector-specific mitigation parameters.     

论支持农业保险发展的财政政策

农业保险是为农业生产者在从事农业生产过程中,对遭受自然灾害和意外事故所造成的经济损失提供保障的一种保险。它被视作推动现代农业,确保农业可持续发展的关键因素。发展农业保险不仅能促进农业发展和农业产品供给,还能减少农民收入波动,增进农民福利。近年来,农业保险越来越引起我国学术界和政府的高度重视,我国财政政策对于农业保险的支持的传统做法正面临改革创新的历史机遇。     

人口老龄化对积极财政政策有效性的影响——兼析延迟退休的宏观经济效应

人口老龄化不但影响到宏观经济的稳定,也会对财政政策的有效性产生影响。将人口老龄化引入动态随机一般均衡模型,分析人口老龄化对4种积极财政政策工具（扩大政府支出、提高劳动所得税起征点、提高劳动所得税累进性和增加公共投资）有效性产生的影响以及延迟退休的动态宏观经济效应,结果表明：人口老龄化扩大了政府支出和政府公共投资对消费产生的挤出效应,降低了4种积极财政政策工具对产出、消费、就业的促进效应,也强化了其对通胀和工资膨胀的提升效应;延迟退休未对私人消费产生挤出效应,有利于就业、产出和消费增长,并有助于稳定通胀和工资膨胀;与财政政策工具相比延迟退休引致的整体社会福利损失较小。人口老龄化降低了积极财政政策的有效性,基于稳定宏观经济和降低社会福利损失的考虑,延迟退休是一个较优的政策选择。     

金融周期、通货膨胀与货币政策

本文在传统新凯恩斯三方程模型的基础上引入金融周期方程,尝试在一个统一的模型框架下探讨金融周期、通货膨胀与货币政策的内生时变动态关系。研究发现,金融危机时期和非危机时期金融周期与通货膨胀间的相互时变联动存在显著差异,金融周期波动对通货膨胀变动具有较好的预测能力,且基本不受危机影响;货币增速剪刀差可能通过市场流动性对货币政策调控金融周期与通货膨胀的力度起到抵消或放大作用,且具有顺周期特征,因此,货币政策当局可考虑引入逆周期调节的宏观审慎政策对金融周期、通货膨胀以及货币增速剪刀差的顺周期局限进行调控。