山西省朔州市耕地与基本农田优化布局研究

耕地和基本农田保护对矿业城市来说具有特殊的意义.以典型矿业城市——山西省朔州市为例,结合当地第三轮土地利用总体规划修编(2006-2020年),以当地2005年(规划基期年)耕地和基本农田的数量、质量为基础,分析其动态流向特征,最后根据自然气候、社会经济条件与耕地质量的一致性,将规划期内(至2020年)朔州市耕地划分为3个区域,分别探讨了各区域耕地利用、土壤改良和生态环境保护方向.     

城市旅游的一个研究剖面：国内外城市旅游产品研究述评

在回顾国内外城市旅游已有文献的基础上,对国外城市旅游产品这一专项内容进行了文献述评,内容集中于城市旅游产品类型包括城市文化旅游产品、城市遗产旅游产品、城市事件旅游产品、城市夜间旅游产品和城市旅游产品,要素包括城市旅游吸引物、城市旅游设施、城市旅游服务、城市可进人性。     

绿色油田建设中存在的问题及对策探讨

文章分析了石油开发对环境的影响,提出了绿色油田建设的必要性与重要性。通过对国内外绿色油田建设现状的调研与对比,总结出目前我国建设绿色油田的瓶颈,提出了建议与对策,并展望了建设绿色油田的前景。     

遗传投影寻踪回归在城市环境质量评价中的应用

引入投影降维的思想,将遗传投影寻踪与回归分析技术运用到城市环境质量评价中。将此技术与神经网络方法进行实例比较,投影寻踪回归方法不但可以合理地作出环境质量的综合评价,而且消除了神经网络方法中类别判断不够精确的影响。     

Comparison of Stream Invertebrate Response Models for Bioassessment Metrics1

Waite, Ian R., Jonathan G. Kennen, Jason T. May, Larry R. Brown, Thomas F. Cuffney, Kimberly A. Jones, and James L. Orlando, 2012. Comparison of Stream Invertebrate Response Models for Bioassessment Metrics. Journal of the American Water Resources Association (JAWRA) 48(3): 570-583. DOI: 10.1111/j.1752-1688.2011.00632.x Abstract: We aggregated invertebrate data from various sources to assemble data for modeling in two ecoregions in Oregon and one in California. Our goal was to compare the performance of models developed using multiple linear regression (MLR) techniques with models developed using three relatively new techniques: classification and regression trees (CART), random forest (RF), and boosted regression trees (BRT). We used tolerance of taxa based on richness (RICHTOL) and ratio of observed to expected taxa (O/E) as response variables and land use/land cover as explanatory variables. Responses were generally linear; therefore, there was little improvement to the MLR models when compared to models using CART and RF. In general, the four modeling techniques (MLR, CART, RF, and BRT) consistently selected the same primary explanatory variables for each region. However, results from the BRT models showed significant improvement over the MLR models for each region; increases in R² from 0.09 to 0.20. The O/E metric that was derived from models specifically calibrated for Oregon consistently had lower R² values than RICHTOL for the two regions tested. Modeled O/E R² values were between 0.06 and 0.10 lower for each of the four modeling methods applied in the Willamette Valley and were between 0.19 and 0.36 points lower for the Blue Mountains. As a result, BRT models may indeed represent a good alternative to MLR for modeling species distribution relative to environmental variables.     

Is Urban Stream Restoration Worth It?1

Kenney, Melissa A., Peter R. Wilcock, Benjamin F. Hobbs, Nicholas E. Flores, and Daniela C. Martínez, 2012. Is Urban Stream Restoration Worth It? Journal of the American Water Resources Association (JAWRA) 48(3): 603-615. DOI: 10.1111/j.1752-1688.2011.00635.x Abstract: Public investment in urban stream restoration is growing, yet little has been done to quantify whether its benefits outweigh its cost. The most common drivers of urban stream projects are water quality improvement and infrastructure protection, although recreational and aesthetic benefits are often important community goals. We use standard economic methods to show that these contributions of restoration can be quantified and compared to costs. The approach is demonstrated with a case study in Baltimore, Maryland, a city with a legal mandate to reduce its pollutant load. Typical urban stream restoration costs of US$500-1,200 per foot are larger than the cost of the least expensive alternatives for management of nitrogen loads from stormwater (here, detention ponds, equivalent to $30-120 per foot of restored stream) and for protecting infrastructure (rip-rap armoring of streambanks, at $0-120 per foot). However, the higher costs of stream restoration can in some cases be justified by its aesthetic and recreational benefits, valued using a contingent valuation survey at $560-1,100 per foot. We do not intend to provide a definitive answer regarding the worth of stream restoration, but demonstrate that questions of worth can be asked and answered. Broader application of economic analysis would provide a defensible basis for understanding restoration benefits and for making restoration decisions.     

Modeled Summer Background Concentration of Nutrients and Suspended Sediment in the Mid‐Continent (USA) Great Rivers1

Angradi, Ted R., David W. Bolgrien, Matt A. Starry, and Brian H. Hill, 2012. Modeled Summer Background Concentration of Nutrients and Suspended Sediment in the Mid‐Continent (USA) Great Rivers. Journal of the American Water Resources Association (JAWRA) 48(5): 1054‐1070. DOI: 10.1111/j.1752‐1688.2012.00669.x Abstract: We used regression models to predict summer background concentration of total nitrogen (N), total phosphorus (P), and total suspended solids (TSS), in the mid‐continent great rivers: the Upper Mississippi, the Lower Missouri, and the Ohio. From multiple linear regressions of water quality indicators with land use and other stressor variables, we determined the concentration of the indicators when the predictor variables were all set to zero — the y‐intercept. Except for total P on the Upper Mississippi River, we could predict background concentration using regression models. Predicted background concentration of total N was about the same on the Upper Mississippi and Lower Missouri Rivers (430 μg l^?1), which was lower than percentile‐based values, but was similar to concentrations derived from the response of sestonic chlorophyll a to great river total N concentration. Background concentration of total P on the Lower Missouri (65 μg l^?1) was also lower than published and percentile‐based concentrations. Background TSS concentration was higher on the Lower Missouri (40 mg l^?1) than the other rivers. Background TSS concentration on the Upper Mississippi (16 mg l^?1) was below a threshold (30 mg l^?1) designed to protect aquatic vegetation. Our model‐predicted concentrations for the great rivers are an attempt to estimate background concentrations for water quality indicators independent from thresholds based on percentiles or derived from stressor‐response relationships.     

Urban land use,mobility and theory of science: exploring the potential for critical realism in empirical research

Academic discussion where the adequacy of positions within theory of science is illustrated by means of examples from empirical research studies seems to be an area of neglect. The purpose of this paper is to contribute to such a debate, using examples from investigations into the relationship between urban structure and travel behaviour. The main research question of these investigations was whether, and to what extent, urban structural conditions are influencing residents' transportation activity. In other words, is there a causal relationship between urban structure and travel behaviour? Furthermore, we asked whether results from studies of the relationship between land use and transport can provide a basis for predictions about the likely consequences of alternative land-use strategies. The methodology and empirical findings of the studies are discussed in the light of the theory of science position labelled ‘critical realism’, in an attempt to relate theory of science to empirical research, but also in order to contribute to the discussion of the usefulness of this specific approach. Copyright © 2002 John Wiley & Sons, Ltd.     

Pathways to urban sustainability

The concept of sustainable development has become very much in vogue in the past decade. We have also observed a shift in the interpretation of this concept from a global perspective to a meso perspective—that is, at a local, regional or sectoral level. This paper aims at highlighting the urban dimension of environmental issues. After a sketch of urban pollution problems and of tools for economic analysis, the notion of urban sustainability will be advocated as a meaningful analytical and policy concept. Next, the main focus of this paper will be on a typological approach to urban sustainability issues on the basis of three characteristic angles, viz. strong and weak sustainability, absolute and relative decoupling and the spatial ecological footprint. Various methodological issues will also be discussed, while the paper will conclude with some perspectives on policy issues. Copyright © 2001 John Wiley & Sons, Ltd.     

特大型城市客运交通碳排放与减排对策研究

本文基于对现有城市交通碳排放测算方法的比较分析,以上海市为例,采用IPCC"自下而上"法对特大型城市客运交通CO2排放进行了测算,结果显示:轨道交通是碳排放效率最高的客运方式,出租车最低;客运交通CO2排放总量增长迅速,且碳源结构发生了较大变化;近年客运交通CO2排放增量主要来自私人载客汽车,同时公务交通在客运交通碳排放中始终占较大比重。由此本文认为,控制客运交通碳排放的关键在于对以私人载客汽车和单位载客汽车为主的个体交通的管理和控制,形成以公共交通为主的交通结构。在此基础上,为了将控制碳排放纳入到城市交通政策目标中去,本文就主要城市交通政策对客运交通碳排放产生的影响进行了深入分析,并得出结论:以往的交通供给、需求管理政策对于抑制客运交通碳排放增长的作用有限;而就目前城市空间发展政策的实施效果而言,也不利于降低居民出行的碳排放水平。文章最后分别从交通供给、需求管理以及城市空间角度给出了控制客运交通碳排放的对策。