铁西区建筑景观时空变化特征及影响因素

城市建筑景观的时空演变特征对城市改造与规划的合理调整有重要的指导作用。本文基于Barista软件、GIS、RS等技术,提取了建筑物的3D信息,并采用建筑占地面积比重、建筑平均高度、建筑密度、建筑形状指数与空间质心模型等指标,分析了沈阳市铁西区建筑景观的时空变化特征与影响因素。结果显示:从1997—2008年,居住与商业建筑占地面积比重增加,工业建筑占地面积比重下降,建筑形状越来越规则,建筑密度降低,建筑在垂直方向上扩展;3个时段内,建筑景观变化的质心先由居住区向工业区转移,再由城市中心向外围移动;经济发展、人口增长与建筑平均高度呈正相关,与建筑密度呈负相关。城市改造政策对城市建筑景观的变化有重要的影响。随着离道路距离的增加,建筑平均高度降低,建筑密度先增高后降低。     

面向生态文明的超循环经济:理论、模型与实例

在全球气候变化背景下,研究适应生态文明要求的新的经济运行模式——超循环经济的基本原理、结构模型、运行机理和实际应用。首先,运用系统结构分析方法梳理不同时期经济运行模式的演进过程:由"从摇篮到产品"的粗放经济,到"从摇篮到坟墓"的末端治理经济,再到"从摇篮到摇篮"的循环经济。延续这一绿色发展趋势,根据文明演化的共生理论和艾根创立的超循环理论,提出超循环经济的理论构想,并描绘"从孕育到孕育"的超循环经济的概念结构。其次,将超循环经济思想应用于林纸拓展系统(EFPS)。在分析中国造纸工业的发展现状和瓶颈及其与林业和生态环境相互关系的基础上,按照资源链、生态链和价值链(简称"三链",或3C)逐层拓展的逻辑顺序,研究EFPS超循环经济的系列结构模型。具体来说,依次建立起各层次的超循环结构模型——制浆造纸系统的资源链核心层模型、供应链系统的资源链拓展层模型、生态环境系统的生态链拓展层模型,以及社会经济系统的价值链拓展层模型。然后将各层次的结构模型综合起来,形成EFPS超循环经济的多重拓展-嵌套整体模型。该模型既能展示EFPS超循环经济系统的全貌,又包含其各层次的系统结构。因此既能为各级政府在制定国家和地区的循环经济总体发展规划时提供参考,又能为制造企业、营林组织、供应链、行业协会等各类经济主体的绿色经营决策提供支撑。最后,在上述实证研究的基础上进行理论提升。一方面提出超循环经济的5R原则:减量化、再循环、再利用、再分配和再培育。另一方面基于5R原则和3C循环链,构建5R-3C理论模型,并研究其5R-3C共生运行机理。研究表明,在超循环经济模式下,产业与生态系统可以实现互利共生的良性循环。以上研究成果的主要创新之处在于:在原理上,揭示了面向生态文明的超循环经济的概念结构、本质属性和5R原则;在机理上,创立了超循环经济的5R-3C模型及其共生运行机理;在实施上,以林纸拓展系统为例,为超循环经济理论的"落地生根"和推广应用构建了具体的多重拓展-嵌套模型。     

The leaf size/number trade-off in herbaceous angiosperms

Aims In this study, we examined the extent to which between-species leaf size variation relates to variation in the intensity of leaf production in herbaceous angiosperms. Leaf size variation has been most commonly interpreted in terms of biomechanical constraints (e.g. affected by plant size limitations) or in terms of direct adaptation associated with leaf size effects in optimizing important physiological functions of individual leaves along environmental gradients (e.g. involving temperature and moisture). An additional interpretation is explored here, where adaptation may be more directly associated with the number of leaves produced and where relatively small leaf size then results as a trade-off of high 'leafing intensity'—i.e. number of leaves produced per unit plant body size.Methods The relationships between mean individual leaf mass, number of leaves and plant body size were examined for 127 species of herbaceous angiosperms collected from natural populations in southern Ontario, Canada.Important findings In all, 88% of the variation in mean individual leaf mass across species, spanning four orders of magnitude, is accounted for by a negative isometric (proportional) trade-off relationship with leafing intensity. These results parallel those reported in recent studies of woody species. Because each leaf is normally associated with an axillary bud or meristem, having a high leafing intensity is equivalent to having a greater number of meristems per unit body size—i.e. a larger 'bud bank'. According to the 'leafing intensity premium' hypothesis, because an axillary meristem represents the potential to produce either a new shoot or a reproductive structure, high leafing intensity should confer greater architectural and/or reproductive plasticity (with relatively small leaf size required as a trade-off). This greater plasticity, we suggest, should be especially important for smaller species since they are likely to suffer greater suppression of growth and reproduction from competition within multi-species vegetation. Accordingly, we tested and found support for the prediction that smaller species have not just smaller leaves generally but also higher leafing intensities, thus conferring larger bud banks, i.e. more meristems per unit plant body size.     

Seaweed production: overview of the global state of exploitation,farming and emerging research activity

ABSTRACT

The use of seaweeds has a long history, as does the cultivation of a select and relatively small group of species. This review presents several aspects of seaweed production, such as an update on the volumes of seaweeds produced globally by both extraction from natural beds and cultivation. We discuss uses, production trends and economic analysis. We also focus on what is viewed as the huge potential for growing industrial-scale volumes of seaweeds to provide sufficient, sustainable biomass to be processed into a multitude of products to benefit humankind. The biorefinery approach is proposed as a sustainable strategy to achieve this goal. There are many different technologies available to produce seaweed, but optimization and more efficient developments are still required. We conclude that there are some fundamental and very significant hurdles yet to overcome in order to achieve the potential contributions that seaweed cultivation may provide the world. There are critical aspects, such as improving the value of seaweed biomass, along with a proper consideration of the ecosystem services that seaweed farming can provide, e.g. a reduction in coastal nutrient loads. Additional considerations are environmental risks associated with climate change, pathogens, epibionts and grazers, as well as the preservation of the genetic diversity of cultivated seaweeds. Importantly, we provide an outline for future needs in the anticipation that phycologists around the world will rise to the challenge, such that the potential to be derived from seaweed biomass becomes a reality.     

Cape Town’s Metabolism: Insights from a Material Flow Analysis

This work aims to contribute to the number of urban metabolism case studies using a standardized methodology. An economy‐wide material flow analysis (EW‐MFA) was conducted on the Metropolitan Municipality of Cape Town (South Africa) for the year 2013, using the Eurostat framework. The study provides insights into the city's metabolism through various indicators including direct material input (DMI), domestic material consumption (DMC), and direct material output (DMO), among others. In order to report on the uncertainty of the data, a set of data quality indicators originating from the life cycle assessment literature was used. The results show that domestic extraction involves significant quantities of non‐metallic minerals, and that imports consist primarily of biomass and fossil fuels. The role of the city as a regional hub is also made clear from this study and illustrated by large quantities of food and other materials flowing through the city on their way to or from international markets. The results are compared with indicators from other cities and with previous metabolism work done on Cape Town. To fully grasp the impacts of the city's metabolism, more work needs to be done. It will be necessary to understand the upstream impact of local consumption, and consumption patterns should be differentiated on a more nuanced level (taking into account large differences between household income levels as well as separating the metabolism of industry and commerce from residential consumption).     

Economy‐wide Material Flow Indicators on a Sectoral Level and Strategies for Decreasing Material Inputs of Sectors

The article presents a method for the calculation of selected economy‐wide material flow indicators (namely, direct material input [DMI] and raw material input [RMI]) for economic sectors. Whereas sectoral DMI was calculated using direct data from statistics, we applied a concept of total flows and a hybrid input‐output life cycle assessment method to calculate sectoral RMI. We calculated the indicators for the Czech Republic for 2000–2011. We argue that DMI of economic sectors can be used for policies aiming at decreasing the direct input of extracted raw materials, and imported raw materials and products, whereas sectoral RMI can be better used for justifying support for or weakening the role of individual sectors within the economy. High‐input material flows are associated in the Czech Republic with the extractive industries (agriculture and forestry, the mining of fossil fuels [FFs], other types of mining, and quarrying), with several manufacturing industries (manufacturing of beverages, basic metals, motor vehicles or electricity, and gas and steam supply) and with construction. Viable options for reducing inputs of agricultural biomass include changes in people's diet toward a lower amount of animal‐based food and a decrease in the wasting of food. For FFs, one should think of changing the structure of total primary energy supply toward cleaner gaseous and renewable energy sources, innovations in transportation systems, and improvements in overall energy efficiency. For metal ores, viable options include technological changes leading to smaller and lighter products, as well as consistent recycling and use of secondary metals.     

工业园区循环经济关联与生态效率评价——以福建省蛟洋循环经济示范园区为例

工业园区因物质能量的高度集聚,生产-消费过程的网络关联,以及区域示范带动效应,在循环经济发展中受到持续关注。本研究以福建省蛟洋循环经济示范园区为例,应用物质流、生态网络和生态效率等测度分析方法,综合评估了2012—2016年间园区循环经济的网络关联和生态效率。研究结果表明:(1)园区物质流结构单一,关联度和稳定度明显较弱;(2)园区网络的韧性不足,关键节点的级联效应显著,尤其对中下游企业的影响程度大;(3)生态效率指数分析发现,园区关键节点企业在循环经济效益方面带动能力不足,影响园区循环经济的前景。为此,从园区网络关联稳定度和企业生态经济效率优化提升的角度,探讨园区未来的循环经济发展策略。可为处于起步阶段的专一化工业园区探索可行的循环经济模式提供借鉴。     

基于“生态系统服务网”理论的国土空间规划研究

生态环境恶化使国土空间的管理从重视开发到重视保护转变,相应的思想体系、理论体系与管理机制需要打破旧的路径依赖,建立新的国土空间规划体系。生态系统服务网理论将生态系统服务供给与需求融合到一起,推动生态系统服务"一张网"与国土空间规划"一张图"的衔接。（1）生态系统服务网的网络属性诠释了山水林田湖草-人生命共同体思想体系;（2）生态系统服务网理论强调供给与需求的有效匹配与融合,是国土空间规划的重要依据;（3）生态系统服务网的尺度特征与国土空间规划层级体系存在对应关系,有助于规划的传导与实施;（4）生态系统服务网中供给能力和空间需求匹配的评价是"双评价"的主要内容,为"三区三线"的划定与落地提供了依据;（5）生态系统服务网的价值评估、空间制图与优化,为确定国土空间开发边界与规模奠定了基础,为两山转化路径提供思路和依据,可有效促进国土空间的高质量开发利用。     

Tracking resource use relative to planetary boundaries in a steady-state framework: A case study of Canada and Spain

There is a growing understanding of the biophysical processes that regulate the stability of the Earth-system, yet human pressures on the planet continue to increase rapidly. Here, recent advances in defining Earth-system thresholds using the planetary boundaries framework are translated down to national and sub-national levels. A set of 10 indicators is developed in a biophysical accounting framework that links the sustainability of resource flows from the biosphere to final consumption. The indicator set includes three measures of physical stocks, three measures of aggregate resource consumption, and four indicators of sustainable scale. The four scale indicators are ratios of (i) cumulative carbon footprint relative to carbon budget, (ii) nutrient use relative to biogeochemical boundaries, (iii) blue water consumption relative to monthly basin-level availability, and (iv) land footprint relative to biocapacity. Taken together, the indicators measure how close high-consuming societies are to meeting the conditions of a “steady-state economy”, defined here as an economy with non-growing physical stocks and flows maintained within shares of planetary boundaries. The framework is applied over a 15-year period to the economies of Canada and Spain, along with two sub-national regions (Nova Scotia and Andalusia). Nova Scotia is the only study site experiencing stable or decreasing biophysical stocks and flows. None of the study sites are consuming resources within their shares of all four planetary boundaries. Overall, the set of indicators provides guidance for prioritizing which environmental pressures need to decline (and by how much) for societies to be more effective stewards of Earth-system stability.     

Informal Trade,Contrabando and Prosperous Socialities in Arequipa,Peru

The article explores trading activities at an outdoor market in the city of Arequipa, Peru, with the intention of discussing how notions of ‘the market’ are negotiated in terms of moralities. More specifically, it seeks to address the way in which the moralities of ‘the market’ are made the object of negotiation in a context where trade is of a more or less informal kind. In particular, the article describes the practices of smuggling (contrabando) across the border with Bolivia, an issue that has been only briefly discussed in the literature on the Andes. The argument is that the practices of petty trade and ‘informality’, ritual payments and brujería (harmful acts, or witchcraft) in the market context should not necessarily or exclusively be seen in terms of resistance as is often suggested. Instead, these practices should be seen in terms of Andean notions of reciprocity and circulation as significant for the establishment and maintenance of prosperity, that is, prosperity understood as relationally created.