Morphology Characteristics of Southern Appalachian Wilderness Streams1

Zink, Jason M., Gregory D. Jennings, and G. Alexander Price, 2012. Morphology Characteristics of Southern Appalachian Wilderness Streams. Journal of the American Water Resources Association (JAWRA) 48(4): 762‐773. DOI: 10.1111/j.1752‐1688.2012.00647.x Abstract: Watersheds without urbanization or impacts from logging are rare in the southern Appalachian Mountains. The Joyce Kilmer/Slickrock Wilderness of North Carolina and Tennessee contains 24 km² of old‐growth forest, with the balance of the wilderness in a mature second‐growth forest. The watersheds of Little Santeetlah and Slickrock Creek are located within the wilderness. Morphological information, including channel dimensions and longitudinal profiles, was gathered from 14 alluvial stream reaches in these watersheds. The study sites had drainage areas from 0.25 to 41.6 km² and stream slopes from 0.014 to 0.104 m/m. Bankfull cross‐section dimensions of the study stream reaches were strongly correlated to drainage area across the observed range of slopes and bed morphology. Cross‐section area and width relationships for the streams in this study did not differ significantly from regional curves for the mountain physiographic region of North Carolina. Observations of these reaches did not suggest a definitive rule regarding the proportion of steps and riffles in streams. Pools occupied greater than 50% of the length in all stream reaches with slopes less than 0.07 m/m. Significant correlation existed between step height ratio and slope, suggesting that step height can be approximated as the product of channel width and slope. Riffle length and riffle slope ratios were also significantly correlated with slope, though pool spacing was not.     

Ecotoudsm Model and Benefits of Periphery Regions in Western Sichuan Province

There are many problems in the minority regions of western Sichuan Province,such as serious soil erosion,fragile ecological environment,low levels of economy and so on.Ad- vantages of tourism resources in theperiphery regionsshould be fully utilized,andmulti-tourismmeets the characteristics and present situation of the minority regions.Themulti-tourism de- velopment modelcan exert the functions of tourism as the key industry.Based on the demands and the internal linkages among different industries,the mo...     

城市化与环境污染：中国省际面板数据的实证研究

对环境库兹涅茨曲线（EKC）假说进行了扩展，选取1998～2005年中国30个省（市、自治区）的面板数据，构建了6类环境污染指标同城市化水平及控制变量间的计量模型，并运用Eviews软件进行了实证检验。研究结果表明：4类污染物同城市化水平之间存在倒U形曲线关系，另外2类污染物同城市化水平之间存在正U形曲线关系，目前中国大体上已经进入U形曲线的右半段，但由于地区发展差距的存在，各地进入曲线右半段的时间不同；控制变量的加入不仅改变了转折点出现的时间，而且改变了某些污染指标同城市化水平之间的U形曲线关系；贸易开放并不一定造成环境的恶化，“污染天堂”假说在中国不成立；产业结构变动是造成环境污染的重要因素；技术进步引致的单位GDP能耗下降能减轻环境污染压力；快速的经济增长将导致更加严重的环境污染。     

AMMONIA REMOVAL FROM COMPOST LACHATE USING ZEOLITE. II. A STUDY USING CONTINUOUS FLOW PACKED COLUMNS

Bench-scale packed zeolite columns were set up and operated to investigate the continuous removal of ammonium ions from compost leachate. The effects of hydraulic retention time (HRT), and particle size of the zeolite on the ammonia adsorption capacity were studied. For both the coarse particle and the powdered zeolite columns, higher ammonia removal efficiencies were achieved with longer HRT (i.e., lower influent flow rate) tests. At the same HRT, ammonia removal efficiencies from tests with powdered zeolite were generally 20% higher than tests with the coarse particle zeolite. A HRT of 6 hours was found appropriate for efficient ammonia removal, and an operating capacity of 1.31 mg N/g zeolite was obtained. Over 98% of the ammonia input from the influent was consistently removed for over 5 bed volumes (BV) of compost leachate flowing through the zeolite column. Zeolite proved to have a great potential as a medium for ammonia removal in treating composting leachate.     

Analysis on the Evolution of Regional Economic Disparity in the West Coast of the Strait

With the implementation of reform and opening-up, the overall economy of China has made brilliant achievements; meanwhile, however, the economic disparity has been enlarging among some regions, and between the city and the countryside. The existence and evolution of this kind of economic disparity is concerned with social stability, sustainable development and the construction of harmonious society, which has gradually become the hotspot in social economic development. The West Coast of the Strait （WCS） located in southeast littoral areas is adjacent to the Pearl and Yangtze River Delta in the south and north and faces Taiwan Province in the east. The stability and development of this region has vital political and economic meaning in the social economic development of our country. It has important theoretical meaning and practical value to research the form, characteristics and evolution of regional economic disparity in the WCS. Based on insightful analysis on existing study results on the WCS, the paper defines the connotation and extension. By a series of absolute and comparative relative evaluation indexes and taking the WCS since 1992 as the study object, the paper makes analysis on different scales including three regions, four regions, 20 cities and 152 counties, quantitatively evaluates the level, characteristics and evolution of the regional economic disparity and compares the regional economic disparity on different scales. The main conclusions are as follows： the variation trend of the absolute disparity of the whole region is obvious and stable, which has presented an inflating trend; the comparative variation trend on a large scale has waved, The comparative disparity of the three regions increased annually from 1992 to around 2000, which had a decreasing trend from around 2000 to 2005; the comparative variation trend on a small scale was not stable, which showed an annual increase of four regions, 20 cities and 152 counties from 1992 to around 2003 and a decrease from around 2003 to 2005; the     

National Red Listing Beyond the 2010 Target

Abstract: Following creation of the 2010 Biodiversity Target under the Convention on Biological Diversity and adoption of the United Nations Millennium Development Goals, information on status and trends of biodiversity at the national level has become increasingly important to both science and policy. National red lists (NRLs) of threatened species may provide suitable data for reporting on progress toward these goals and for informing national conservation priority setting. This information will also become increasingly important for developing species‐ and ecosystem‐based strategies for climate change adaptation. We conducted a thorough global review of NRLs in 109 countries and analyzed gaps in NRL coverage in terms of geography and taxonomy to determine priority regions and taxonomic groups for further investment. We then examined correlations between the NRL data set and gross domestic product (GDP) and vertebrate species richness. The largest geographic gap was in Oceania, followed by middle Africa, the Caribbean, and western Africa, whereas the largest taxonomic gaps were for invertebrates, fungi, and lichens. The comprehensiveness of NRL coverage within a given country was positively correlated with GDP and negatively correlated with total vertebrate richness and threatened vertebrate richness. This supports the assertion that regions with the greatest and most vulnerable biodiversity receive the least conservation attention and indicates that financial resources may be an integral limitation. To improve coverage of NRLs, we propose a combination of projects that target underrepresented taxa or regions and projects that provide the means for countries to create or update NRLs on their own. We recommend improvements in knowledge transfer within and across regions as a priority for future investment.     

Regional Economic Types and Development Strategy of Small Towns in Suburb Beijing

Abstract

The purpose of this article is to classify the regional economic types and development dynamics of small towns in suburb Beijing by applying the classification methods developed by Nelson’s method and Location Quotient method into 183 small towns in Beijing. Four types of small towns are thus identified, including urban agriculture dominated towns, manufacturing dominated towns, service industry dominated towns and comprehensive type towns with balanced economic development. Within the environment of geographical information system, the spatial distribution pattern of four types of small towns with their evolution trend is analyzed. The results indicate that four types of small towns have obvious ‘core-periphery’ spatial structure but with different functional orientations and evolution mechanisms. Based on this, the different development strategies for each type of small towns are summarized, providing a scientific reference for the differentiating planning and development strategies of these small towns.     

沪苏通三角区产业经济一体化时空演变及其影响机制

以沪苏通三地为例,研究了三地之间产业经济一体化的时间和空间过程,从空间相互作用理论视角探讨了地区之间的互补性、可运输性和介入性等因素的影响机制。研究认为改革开放以来沪苏通三地构成的三角区产业经济一体化经历了由弱到强、简单到复杂的关系,特别是2005年以后,在区域竞争和合作的大背景下,上海藉由定位转向和结构升级重塑区域地位的战略取向使得沪苏通三地产业经济关系步入了一体化重构轨道。三地之间未来要形成3边均强的网络化的产业经济一体化格局,应通过加强地区之间的合作,放大各地之间的互补性,通过减少地区之间非理性的竞争,改善地区之间空间分割。     

Development and Application of an Agricultural Intensity Index to Invertebrate and Algal Metrics from Streams at Two Scales

Research was conducted at 28‐30 sites within eight study areas across the United States along a gradient of nutrient enrichment/agricultural land use between 2003 and 2007. Objectives were to test the application of an agricultural intensity index (AG‐Index) and compare among various invertebrate and algal metrics to determine indicators of nutrient enrichment nationally and within three regions. The agricultural index was based on total nitrogen and phosphorus input to the watershed, percent watershed agriculture, and percent riparian agriculture. Among data sources, agriculture within riparian zone showed significant differences among values generated from remote sensing or from higher resolution orthophotography; median values dropped significantly when estimated by orthophotography. Percent agriculture in the watershed consistently had lower correlations to invertebrate and algal metrics than the developed AG‐Index across all regions. Percent agriculture showed fewer pairwise comparisons that were significant than the same comparisons using the AG‐Index. Highest correlations to the AG‐Index regionally were ?0.75 for Ephemeroptera, Plecoptera, and Trichoptera richness (EPTR) and ?0.70 for algae Observed/Expected (O/E), nationally the highest was ?0.43 for EPTR vs. total nitrogen and ?0.62 for algae O/E vs. AG‐Index. Results suggest that analysis of metrics at national scale can often detect large differences in disturbance, but more detail and specificity is obtained by analyzing data at regional scales.     

武汉冬季大气PM2.5小时分辨率源贡献识别及潜在影响域分析

冬季是我国大气细颗粒物(PM_2.5)污染较为严重的时段,武汉市PM_2.5受到明显的区域传输影响.本研究基于小时分辨率PM_2.5组分观测数据,采用受体模型,解析武汉冬季大气PM_2.5各类源的实时贡献.结合轨迹聚类和浓度权重,识别影响各类源的传输路径和潜在源区.武汉冬季大气平均ρ(PM_2.5)为（75.1±29.2）μg·m^-3.观测期间共有两次污染过程,第一次污染过程主要受西北方向气团影响,水溶性离子升高是PM_2.5呈现高值的主要原因,ρ（NH⁺₄）、ρ（NO^-₃）和ρ（SO■）分别是清洁时段的1.6、 1.7和2.1倍;第二次污染过程则以正东方向气团为主,二次有机组分有明显的生成.对武汉冬季大气PM_2.5贡献最大的是二次源（34.1%）,其次是机动车尾气（23.7%）、燃煤（11.5%）、道路尘（10.9%）、钢铁冶炼（8.7...