Mineral resources in the age of climate adaptation and resilience

This article discusses issues on resources availability to achieve climate adaptation and resilience for cities and infrastructures. In the age of climate change, there could be cascading failures through a range of infrastructure breakdowns. Direct and indirect damage costs could exceed what had been estimated in traditional risk assessments. This could be exacerbated through abrupt price peaks in international supply chains of minerals, and through events happening in remote parts of the world that affect extraction and vulnerable industries. The core argument made here is one of feedbacks: climate adaptation has significant resource implications, and how resources are being used will have implications on climate strategies. Industrial Ecology has a role to play assessing those interactions and providing a better grasp of the spatial dimension of material flows, partly to track those flows and align them to specific actors, and partly to address interlinkages across different flows and their stocks (‘the resource nexus’). Methodological novelties are needed to better understand the resource base and the socio‐economic dimension, especially on innovations and transitions that can help to cope with the challenges ahead. Altogether this would enable research to establish an evidence base on sustainable materials to deliver parts of the UN Sustainable Development Goals (SDGs) and to reassess infrastructure assets and the mineral resources in the age of climate adaptation and resilience.     

治沟造地背景下延安市农业生态经济系统耦合发展分析

治沟造地是继退耕还林工程后延安市实施的又一项重大生态环境治理工程。研究治沟造地工程背景下延安市农业生态经济系统耦合关系的发展变化,对科学评价治沟造地工程生态经济效益和黄土高原地区农业生态经济协调与可持续发展具有重要意义。本研究通过构建农业生态经济系统耦合协调度模型和耦合度模型,定量分析了2010—2018年延安市农业生态与农业经济系统的综合评价指数变化、耦合协调状态及耦合度演变趋势。结果表明: 2010—2018年间,延安市农业生态系统综合评价指数和农业经济系统综合评价指数均呈现S型增长曲线,两者变化趋势较为一致;农业生态经济系统耦合协调度指数由0.51增长至0.72,耦合协调状态由初级协调水平发展为良好协调水平,说明该区域农业生态与经济关系不断改善,系统耦合关系向相互协调的方向发展;研究期间,延安市农业生态经济系统耦合演变过程较为复杂,系统耦合趋势经历了“衰退耦合、协调耦合、修复耦合、协调耦合”阶段,2018年耦合关系处于经济快速增长的协调发展阶段。治沟造地工程促进了农业生态经济系统的耦合协调发展,但其生态经济效益具有一定的滞后性。     

中国海洋资源环境经济系统承载力及协调性的时空演变

中国海洋复合系统承载力研究对海洋标准化发展具有重要意义。引入环境EKC机理,通过可变模糊识别算法,结合相关研究构建承载力指标体系和评价体系对中国海洋资源环境经济2006—2014年承载力情况进行评价分析;利用三元协调发展模型对复合系统承载力进行协调发展测度;最后通过灰色关联模型测度承载力驱动因素以期为中国海洋复合系统可持续发展提供参考依据。研究结果表明:(1)中国海洋复合系统承载力时序变化良好;空间上天津、上海、海南承载力较高,呈南北中"三足鼎立"格局,河北、广西承载力较低;(2)承载力协调发展状况也呈良性发展,但区域间差异较大,海南、山东协调性较高,海南、上海、天津协调发展度较高,其余大部分地区均有待提高。(3)海洋经济规模与产业结构、环境治理、资源丰富度分别影响着海洋经济、资源、环境承载力。     

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。     

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).     

新疆伊犁河流域生态服务价值对土地利用变化的响应

以伊犁河流域为研究对象,运用GIS手段和生态经济学方法,采用Costanza生态系统服务价值计算公式,参照谢高地等人的中国陆地生态系统服务单位面积价值,结合敏感度分析,探讨了伊犁河流域1985-2005年土地利用和生态系统服务价值的变化特征。研究结果表明:1985-2005年间伊犁河流域土地利用处于发展阶段,土地利用程度呈增大趋势。研究期内生态系统服务价值总体有所上升,从482.83×108元上升到506.44×108元,增加了23.61×108元:水域和耕地对研究区总体服务功能变化的贡献率最大,而牧草地生态服务功能的下降对研究区总体生态服务功能的增加具有较大负贡献。研究区生态经济的发展已处于协调水平的边缘,需要加强对生态环境的保护力度。     

基于生态效率的辽宁省循环经济分析

生态效率与循环经济相辅相成。基于区域生态效率评价是考量区域循环经济的重要内容,又基于目前对于循环经济与生态效率结合的实证研究相对较少,因此,以生态效率理论为基础,对我国最早开展循环经济的试点省份——辽宁省的循环经济发展作以综合衡量。通过生态效率度量模型与循环经济度量模型,以辽宁省1990～2008年数据为基础,运用基于熵权的TOPSIS方法,分别计算了19a间辽宁省各年的资源效率、环境效率、生态效率,进而综合评价了辽宁省循环经济发展轨迹。研究表明：在19a间,辽宁省生态效率总体呈现波动上升态势,经历了传统经济发展模式——末端治理模式——循环经济模式的转变;19a间,辽宁省循环经济发展状态总体上处于循环性不断增强的状态,即经济发展的同时,环境压力不断减小。研究证明了辽宁省2002年实行循环经济以来取得了明显成效,对全国尤其是东北地区发展循环经济,走新型工业化道路具有重要的示范意义。     

Diurnal export and carbon economy in an expanding source leaf of cucumber at contrasting source and sink temperature

Effects of contrasting temperatures of an expanding leaf (source) and of remaining plant parts (sink) on diurnal export and distribution of carbon were studied in seedlings of Cucumis sativus L., cv. Farbio. The time course of the rate of export was calculated by measuring simultaneously the exchange of ¹⁴CO₂ and the amount of ¹⁴C in the source leaf by means of a Geiger-Müller detector using a steady-state labelling technique. In all treatments average export rate during the night (16 h) was maximally 50% of the average rate during the 8-h day. Temperature affected the diurnal course of export via the source leaf and the sink in different ways. At a source leaf temperature of 25 or 30°C export stopped 12 h after start of the night, whereas at 20°C export continued throughout the night. However, the total amount of carbon exported during a 24 h cycle, expressed as a proportion of the amount of carbon assimilated, was the same at source leaf temperatures of 20 or 30°C. Thus source leaf temperature did not affect the distribution of assimilates between source and sink, in contrast to sink temperature. After 24 h at a sink temperature of 30°C, 20% more ¹⁴C was exported to plant parts below the source leaf than with a sink temperature of 20°C, at the expense of carbon remaining in the source. During the day less starch and more structural dry matter was formed at a source leaf temperature of 30°C than at 20°C. After a complete day/night cycle, however, there was no difference between the treatments. Starch was the primary carbon source during the night, and the decline in the rate of export coincided with the depletion of starch. Thus the decline in the rate of export at a source leaf temperature of 25 or 30°C at 12 h after the start of the night was due to the depletion of starch at that time. Similarly, at 20°C export could continue until the end of the night as the starch degradation supplied assimilates during the whole night.