深圳城市系统代谢的变化与废物生成效应

深圳是从小镇向现代化大都市快速转变的典型个例。本文从生态系统物质代谢和能量流动的角度出发 ,定性描述城市化过程中代谢的突出问题 ,分析了深圳城市系统代谢 2 0年间有关特征的显著变化、相关废物产生的机理 ,从深层上探讨了解决这些问题的途径和对策 ,为小城镇的快速城市化提供借鉴     

马克思的新陈代谢断裂理论与新型城市化

新陈代谢断裂是人与自然之间的物质循环断裂,本质就是由于资本的逻辑而导致的城乡社会之间物质循环的断裂,一些食物运输到城市,经消费后在城市造成了环境污染,而另一方面农村土地的肥力无法得到补偿,资本的逐利性是造成资本主义生态断裂的根源.新型城市化应是生态文明的城市,促进城乡的一体化发展,促进城乡之间物质的合理循环.     

城市能源代谢的异质性分析——以北京市为例

充分探究城市能源代谢过程中部门间的内在差异,深入解析并评估其对城市能源代谢过程的影响对于进一步优化城市能源代谢结构,推动节能减排、提质增效具有重要价值。本文基于引力模型分析城市能源代谢过程中能源流两端连接节点的属性差异,选取煤、石油、天然气三种能源,以北京市非首都功能疏解部门为例探究要素差异及部门自身属性差异在能源代谢过程中的影响;利用情景分析法,分析两种能源优化强度和三种部门疏解强度的6种组合情景下四部门的不同种类能源消耗的变化。结果表明,不同要素对部门能源消耗的正负反馈机制以及不同部门对不同能源偏好程度均存在异质性,这种异质性导致不同政策情景对北京市非首都功能疏解部门能源结构优化的作用效果不同。强优化强疏解情景对于制造业部门煤和天然气能源的替代最为有利,低疏解强优化情景对控制交通业及批发和零售业部门的能源消费,改善教育业的能源消费结构最有利。     

Thermal Eco‐cities: Green Building and Urban Thermal Metabolism

Eco‐city projects are becoming increasingly prevalent throughout the globe and are often marketed as ‘new’ urban environments focused on achieving sustainable urban living while promoting environmental–economic transitions towards a low‐carbon technological and industrial base. The article argues for the need to consider the thermal aspects of urban metabolism, while at the same time focusing on the link between individual buildings and eco‐city master plans and wider economic development strategies at a state level. In so doing, the article encourages critical analysis of eco‐city design and planning, while keeping a focus on the role of specific building structures within eco‐cities as examples of the intermeshing of what can be termed a ‘political ecology of scale’ which stretches from specific buildings' climatic characteristics, to the metabolic master plan for eco‐cities, to provincial, regional and state‐level plans for the integration of eco‐cities within wider economic and political development trajectories. The article focuses on Masdar, in Abu Dhabi, an eco‐city under construction at the time of writing.     

Human appropriation of net primary production in the United Kingdom, 1800-2000 : Changes in society's impact on ecological energy flows during the agrarian-industrial transition

This paper presents an empirical analysis of the United Kingdom's society's long-term intervention into the energy flows of domestic terrestrial ecosystems through the human appropriation of aboveground net primary production (aHANPP) covering the period 1800-2000. The depicted aHANPP trajectory and the historical development of its components are discussed in view of a continuously increasing population and the transition process from an agrarian to an industrial socioecological regime. During the 19th century, aHANPP shows a steady decline from its level of 71% in 1800. While even higher levels were reached during the mid 20th century, the trend during the last forty years of the period under investigation again shows a reduction of aHANPP, which lies at 68% in the year 2000. The high values of aHANPP in the United Kingdom are primarily attributable to the limited amount of forest in comparison to large agricultural areas. At the beginning of the studied period, the relative stabilisation or even decrease in aHANPP in comparison to population development was made possible through the area expansion of and productivity increases on cropland and permanent pastures. Later this was made possible through the outsourcing of biomass harvest, by satisfying local nutritional demands by means of overseas imports, and as from the mid 20th century through huge amounts of fossil fuel based inputs into agriculture (e.g. increased amounts of fertilizers and motorized traction) which allowed increases in biomass harvest to be decoupled from HANPP.     

糖尿病肾病患者血清脂蛋白(a)和D-二聚体检测的临床研究

目的分析糖尿病肾病患者血清脂蛋白、D-二聚体的水平变化及与糖尿病肾病的关系。方法根据尿白蛋白排泄率(Urinary Albumin Excretion rate,UAE)将134例2型糖尿病(Diabetes Mellitus,DM)患者分为单纯糖尿病组(Simple Diabetic Mellitus,SDM组)和糖尿病肾病组(DN组),200例健康体检者作为正常对照组分别测定各组血清Lp(a)、D-D的水平。结果 SDM组Lp(a)和D-D水平与健康对照组比较无统计学差异(P>0.05),但DN组Lp(a)和D-D水平显著高于健康对照组(P<0.01)。结论 DN患者血清Lp(a)和D-D水平明显升高,在DN的早期诊断和病情监测有一定意义。     

城市化与可持续城市化的理论探讨

快速城市化给我国城市化的健康发展带来巨大挑战。本文从结构、过程和功能三方面分析了城市生态系统的属性,探讨了城市化的概念及其正负两方面的效应,提出了要实现可持续的城市化,必须保证城市生态系统的结构合理、过程高效、功能完善,并从这三方面讨论了可持续城市化的内涵:随着城市化进程的不断推进,城市人均生态足迹增长得到控制,城市代谢效率不断提高,居民福利不断增长。     

Effects of food consumption patterns on paddy field use in Taiwan

Societal metabolism and land use are significant and interrelated issues, and play a role in sustainable development. How a society's metabolism relates to local land use is typically affected by the particular context of the society under study, which is usually shaped by many factors, including economic, ecological, cultural, technological, and political factors. This study examines the effects of changes in food consumption patterns – decreasing per capita consumption of rice and increasing per capita consumption of wheat flour and meat – on the use of paddy fields in Taiwan. Although rice is grown domestically, wheat, which is a substitute for rice, is mainly imported. Moreover, the domestic livestock industry depends heavily on imported crops for low-cost feed. Accordingly, dietary changes have significantly decreased the demand for local paddy fields to grow crops. Additionally, the diversion of paddy fields to grow forage crops, which has been promoted by the Taiwanese government by guaranteeing prices for feed maize for 14 years, was discouraged when Taiwan joined the World Trade Organization in 2002, as Taiwan was required at that time to reduce by 20% its aggregate measure of support. The presented Taiwan case provides an empirical example of how a change in input characteristics (supply sources in a spatial dimension) of societal metabolism can, together with other factors, significantly affect local paddy fields, and discusses the underlying implications for sustainable development.     

Comparative study of properties and acceptability of Haitian and US honey‐roasted peanuts

A honey‐roasted peanut product, flavoured with ginger and anise, was recently developed in Haiti in an effort to increase the consumption of locally grown peanuts. The objective of this study was to compare quality and consumer acceptability of the Haiti product with a traditional US‐manufactured brand. Haitian panellists (199) evaluated colour, appearance (dry/oily), crunchiness, peanut flavour and sweetness of the products using five‐point just‐about‐right scales. Colour (Minolta chromameter), hardness (TA.XT2i texture analyser fitted with a TA42 knife blade) and moisture (Denver IR‐30 moisture analyser), lipid (ethyl ether extraction) and sugar (Dionex DX‐500 high pressure liquid chromatography system) contents of the products were also determined. The Haiti product was significantly (P < 0.05) darker brown, harder and contained more (P < 0.05) sucrose and glucose but less (P < 0.05) lipid and fructose than the US product. Panellists indicated that crunchiness, peanut flavour and sweetness of both products were just right. The US product had acceptable appearance but was rated too light (hue angle = 69.6 ± 0.70, L‐value = 58.2 ± 0.47) in colour, whereas the Haiti product appeared too dry and dark (hue angle = 62.6 ± 2.79, L‐value = 44.6 ± 2.22). The Haiti peanuts were not deskinned, and their testae may have decreased the acceptability of the product's appearance and colour. The Haiti product was significantly (P < 0.05) just right to the female panellists and to the 21‐year plus panellists from all income groups. Deskinning of the peanuts and increased oil addition during roasting may improve the acceptability of the Haiti product, especially to 14–20 year olds. Decrease in sugar content may also make the Haiti product more appealing to this age group and to male Haitians.     

Global patterns of socioeconomic biomass flows in the year 2000: A comprehensive assessment of supply, consumption and constraints

Human use of biomass has become a major component of the global biogeochemical cycles of carbon and nitrogen. The use of land for biomass production (e.g. cropland) is among the most important pressures on biodiversity. At the same time, biomass is indispensable for humans as food, animal feed, raw material and energy source. In order to support research into these complex issues, we here present a comprehensive assessment of global socioeconomic biomass harvest, use and trade for the year 2000. We developed country-level livestock balances and a consistent set of factors to estimate flows of used biomass not covered by international statistics (e.g. grazed biomass, crop residues) and indirect flows (i.e. biomass destroyed during harvest but not used). We found that current global terrestrial biomass appropriation amounted to 18.7 billion tonnes dry matter per year (Pg/yr) or 16% of global terrestrial NPP of which 6.6 Pg/yr were indirect flows. Only 12% of the economically used plant biomass (12.1 Pg/yr) directly served as human food, while 58% were used as feed for livestock, 20% as raw material and 10% as fuelwood. There are considerable regional variations in biomass supply and use. Distinguishing 11 world regions, we found that extraction of used biomass ranged from 0.3 to 2.8 t/ha/yr, per-capita values varied between 1.2 and 11.7 t/cap/yr (dry matter). Aggregate global biomass trade amounted to 7.5% of all extracted biomass. An analysis of these regional patterns revealed that the level of biomass use per capita is determined by historically evolved patterns of land use and population density rather than by affluence or economic development status. Regions with low population density have the highest level of per-capita biomass use, high-density regions the lowest. Livestock, consuming 30-75% of all harvested biomass, is another important factor explaining regional variations in biomass use. Global biomass demand is expected to grow during the next decades; the article discusses some options and possible limitations related to such a scenario.