Circuits of scrap: closed loop industrial ecosystems and the geography of US international recyclable material flows 1995–2005

The recycling of scrap material has been identified as an important strategy in the larger theory of industrial ecology. Industrial ecology argues that the traditional model of industrial activity needs to be transformed into a 'closed loop' industrial ecosystem where used materials (scrap) and by-products would substitute for virgin materials during production processes. The recycling of scrap material forms part of this larger effort to reduce the overall environmental impact of production and consumption. A key, but as yet, unresolved question in this process is the geographic scale (local, regional, national, global) at which loop closing should take place. This preliminary empirical research examines the export and import geography of the seven largest (by weight) US scrap commodities (iron and steel, paper, plastics, aluminium, copper, nickel and zinc) between 1995 and 2005 to ascertain the extent to which US scrap flows overseas and how that might affect our understanding of how material loops can close. Other than an integrated export and import relationship with Canada, the results suggest that there are two distinct circuits of scrap flows in the USA. The USA exports a substantial portion of the recyclable scrap generated each year to rapidly developing countries, while importing smaller quantities of scrap from the EU. With the major exception of exporting higher value iron and steel scrap to China, the US tends to export lower value scrap and import higher value scrap. In part this reflects imbalances in the supply and demand for scrap between the USA and the developing world, the lack of potentially available scrap and the absence of a robust recycling infrastructure in the developing world. Although such scrap circuits are probably not ideal, the use of US scrap in the developing world is both a realistic and preferable alternative in the short to medium term than virgin production.     

Research Approaches for Understanding,Enhancing, and Monitoring Community Resilience

The growing interest in the understanding of community resilience suggests a need for improving research approaches. This article reviews methods used to date, and suggests opportunities for expanding the range and efficacy of approaches used to understand, improve, and monitor the coupled social and ecological aspects of community resilience. We explore three potential foci: research approaches that enhance understanding of community resilience; those that help to improve community resilience through the research process; and the further development of methods to guide monitoring. Most studies have relied on mixed and multistaged methods, including in-depth interviews and case studies. We comment on the wide range of approaches used, and suggest others that could be valuable. There is particular scope for greater use of cumulative studies, historical or retrospective studies, participatory methods, and systems approaches, and a need for more methods that explore the coupling of social and ecological dimensions.     

美国科罗拉多河高速水流实验对下游水生生态系统的影响及启示

科罗拉多河的适应性管理处于世界领先水平。美国为研究格伦峡谷大坝对下游水生生态系统的影响而进行了3次高速水流实验,取得了显著的生态效益,也积累了许多宝贵经验。分析显示,利益相关方参与是该实验成功的体制保障,跟踪监测与评估是实验成功的技术保障,闸坝适应性调度是河流保护与管理的有效手段。该实验的实施过程和效果对我国闸坝调度有许多有益的启示。例如,对下游水生生物和湿地生态系统的保护应作为闸坝调度的目标之一,应加强闸坝适应性调度的实验和研究,促进利益相关方参与河流保护与管理。     

生态遥感新锐——轻小型无人机的应用

基于研究对象视角梳理轻小型无人机遥感手段在生态学研究中的应用现状,重点分析了无人机在不同生态对象应用的优势和局限：优势主要在于其能够高灵活性、高分辨率地获取各生态对象的数据,为较大规模的生态研究提供了便利。在农田生态系统应用中主要关注农田信息检测、自动化农作等方面,但在这方面的应用还比较单一,缺乏更深层更全面的系统化应用;在森林草地中主要关注植被结构参数提取、生物量反演等,在数据采集过程中应注意设备的稳定性避免对数据准确性造成影响;城市生态系统主要集中在城市环境监测和测绘方面,同时城市方面飞控政策尚待完善;水生生态系统主要关注水生动植物监测和潮间带观测等,大规模监测也对设备续航和数据标准化处理提出了要求;动物研究应用中主要关注动物迁徙规律、物种分布等方面,在监测过程中需注意不要对动物栖息造成干扰。总的来说,无人机应用局限主要在于其获取的数据处理尚未标准化,飞控政策尚未成熟和硬件续航等方面。在此基础上探讨了未来无人机遥感在生态学研究的应用趋势：随着无人机智能化的软硬件发展和云端生态大数据的建立,无人机数据的获取和处理将更加智慧化,多源的无人机遥感数据将会更好地服务于生态学研究。     

Increased soil organic carbon storage in Chinese terrestrial ecosystems from the 1980s to the 2010s

Journal of Geographical Sciences - Soil stores a large amount of the terrestrial ecosystem carbon (C) and plays an important role in maintaining global C balance. However, very few studies have...     

Estimation and analysis of the ratio of transpiration to evapotranspiration in forest ecosystems along the North-South Transect of East China

Journal of Geographical Sciences - The ratio of transpiration to evapotranspiration (T/ET) is a key parameter for quantifying water use efficiency of ecosystems and understanding the interaction...     

中美俄加陆域碳汇对人为增温的消减贡献

作为主要的气候强迫因子,CO2与人类活动密切相关,但很多研究往往忽视了陆地生态系统碳汇对人为排放CO2增温的消减作用.俄罗斯、加拿大、中国和美国是世界上地域面积最大、且社会经济处于不同发展阶段的4个国家,将短时期内CO2排放所引起的辐射强迫进行量化分析,对于评估人为和自然因素对气候的影响非常重要.本文基于CO2同化数据...     

Detecting climate change effects on forest ecosystems in Southwestern Romania using Landsat TM NDVI data

Nowadays, Southwestern Romania faces a large-scale aridization of the climate, revealed by the rise of temperatures and the decline of the amount of precipitations, with negative effects visible, among others, in the desiccation of forest vegetation. The present study means to identify the changes that occurred, quality-wise, in the past two decades （1990-2011） in forest vegetation in Southwestern Romania, and to establish the link between those changes and extant thermal stress in the region, whose particular features are high average annual and seasonal temperatures. In order to capture the evolution in time of cli- mate aridization, a first step consisted in using climate data, the temperature and precipitation parameters from three weather stations; these parameters were analyzed both individually and as aridity indexes （De Martonne and UNEP）. In order to quantify the changes in forest vegetation, NDVI indexes were used and analyzed, starting off from Landsat satellite images, acquired at three distinct moments in time, 1990, 2000 and 2011. In order to identify the link between the changes of NDVI index values and regional thermal stress, a yardstick of climate changes, statistical correlations were established between the peak values of average annual temperatures, represented in space, and negative changes in the NDVI index, as revealed by the change-detection analysis. The results obtained indicated there is an obvious （statistically significant） connection between thermal stress and the desiccation （degradation） of forest species in the analyzed area, with false acacia （Robinia Pseudoacacia） the main species to be impacted.     

BOOK REVIEWS

Books reviewed in this article: The Mexican Colonial Copper Industry. Elinore M. Barrett . The Control Revolution: Technological and Economic Origins of the Information Society . James R. Beniger . Land Degradation and Society . Piers M. Blaikie And Harold C. Brookfield , Eds . La carte, mode d'emploi. Roger Brunet . France: les dynamiques du territoire . Roger Brunet AND Jacques Sallois , EDS. At the Crossroads—The Mineral Problems of the United States . Eugene N. Cameron . A Census of One Billion People , Papers for International Seminar on China's 1982 Population Census. Li Chengrui , ED. Les Milieux “Naturels” du Globe . Jean Demangeot . The Geophysiology of Amazonia: Vegetation and Climate Interactions : Robert E. Dickinson , ED. Tenn-Tom Country . James F. Doster And David C. Weaver . Family Farming in Europe and America . Boguslaw Galeski And Eugene Wilkening , EDS. The Geography of Urban Transportation . Susan Hanson , Ed. Combating Desertification in Developing Countries . J. K. Jain , ED. Cartography in France—1660–1848. Science, Engineering and Statecraft . Josef W. Konvitz . Distribution of Distances in Pregeographical Space . Hans Kuiper . Physical Geography Lab Manual: A New Experimental Approach . Neal G. Lineback And John M. Harlin . Physical Geography: A Landscape Appreciation , 2nd ed. Tom L. Mc Knight . The Desert Is No Lady: Southwestern Landscapes in Women's Writing and Art . Vera Norwood And Janice Monk , EDS. France: A Geographical, Social, and Economic Survey . Philippe Pinchemel , translated, by D. Elkins and T. H. Elkins. Gene Banks and the World's Food . Donald L. Plucknett , Nigel J. H. Smith , J. T. Williams , And N. Murthi Anishetty . Latin American Development: Geographical Perspectives . David Preston , Ed. Making Sense of Development: An Introduction to Classical and Contemporary Theories of Development and Their Application to Southeast Asia . P. W. Preston . The History of the Countryside. Oliver Rackham . The Third World in Perspective . H. A. Reitsma AND J. M. G. Kleinpenning . The Industrial Geography of Australia . David C. Rich . The Recruiting Game , 2nd Ed., revised. John F. Rooney , JR. A Cultural Geography of North American Indians . Thomas E. Ross AND Tyrel G. Moore , EDS. Eastern Europe . Dean S. Rugg . Human Territoriality: Its Theory and History . Cambridge Studies in Historical Geography: 7. Robert David Sack . Experimental Fluvial Geomorphology . Stanley A. Schumm , M. Paul Mosley , AND William E. Weaver . The New Urban Landscape . David Schuyler . Atlas of American Women . Barbara Gimla Shortridge . Impacts of Hazardous Technology: The Psycho-Social Effects of Restarting TMI-1 . John Sorensen , Jon Soderstrom , Emily Copenhaver , Sam Carnes AND Robert Bolin . Modern Physical Geography , 3rd Ed., (Third Edition). Arthur N. Strahler AND Alan H. Strahler . India: Economic Resource Base and Contemporary Political Patterns . B. L. Sukhwal .     

Carbon neutrality and mitigating contribution of terrestrial carbon sink on anthropogenic climate warming in China,the United States,Russia and Canada

Carbon dioxide(CO_2) is a major climate forcing factor, closely related to human activities. Quantifying the contribution of CO_2 emissions to the global radiative forcing(RF) is therefore important to evaluate climate effects caused by anthropogenic and natural factors. China, the United States(USA), Russia and Canada are the largest countries by land area, at different levels of socio-economic development. In this study, we used data from the CarbonTracker CO_2 assimilation model(CT2017 data set) to analyze anthropogenic CO_2 emissions and terrestrial ecosystem carbon sinks from 2000 to 2016. We derived net RF contributions and showed that anthropogenic CO_2 emissions had increased significantly from 2000 to 2016, at a rate of 0.125 PgC yr~(-1). Over the same period, carbon uptake by terrestrial ecosystems increased at a rate of 0.003 PgC yr~(-1). Anthropogenic CO_2 emissions in China and USA accounted for 87.19% of the total, while Russian terrestrial ecosystems were the largest carbon sink and absorbed 14.69 PgC. The resulting cooling effect was-0.013 W m~(-2) in 2016, representing an offset of-45.06% on climate warming induced by anthropogenic CO_2. This indicates that net climate warming would be significantly overestimated if terrestrial ecosystems were not included in RF budget analyses. In terms of cumulative effects, we analyzed RFs using reference atmospheres of 1750, at the start of the Industrial Revolution, and 2000, the initial year of this study. Anthropogenic CO_2 emissions in the study area contributed by + 0.42 W m~(-2) and +0.32 W m~(-2) to the global RF, relative to CO_2 levels of 1750 and 2000, respectively. We also evaluated correlations between global mean atmospheric temperature and net, anthropogenic and natural RFs. We found that the combined(net) RF caused by CO_2 emissions accounted for 30.3% of global mean temperature variations in 2000–2016.