Finding upper-level sets in cellular surface data using echelons and saTScan

Across a spectrum of contemporary contexts from public health to landscape ecology and natural resources, there is need for objective determination of elevated occurrence in phenomena such as disease incidence and biodiversity. Occurrences of such phenomena constitute response surfaces, but data regarding the surface is typically acquired in a cellular framework. The cells may comprise a regular grid, or may be of irregular shapes such as counties in which statistics are collected. Echelons are a topologically based approach to systematic determination of spatial structure in a step surface. Spatial scan statistics are a probability-based approach to the same issue when interest lies in a rate variable. Here we examine the use of echelons both separately and in conjunction with the SaTScan implementation of spatial scan statistics for purposes of determination and visualization of upper-level sets. Consideration is given to both conventional geographic space and to the cellular pseudo-space of contingency tables for ordered categorical variables. Received: August 2002 / Revised: July 2005     

Cleaner production and UNIDO

Even though there were many similar-sounding themes and works at the Stockholm (1972) and Rio (1992) conferences, there are two fundamental differences for industrial development between the plans of action elaborated by the two conferences. One difference is the message, i.e. the nature of the industrial environmental problem. The new message assigns priority to pollution prevention over pollution control because it is a more efficient and effective response to emerging environmental concerns. The other difference is the media, i.e. the major forces of development as well as environmental management agencies must be actively involved in meeting emerging environmental concerns. As the lead organization in the UN system for industrial development, UNIDO is cooperating with many developing countries to implement Agenda 21 of the Rio Conference. UNIDO is promoting the new message of cleaner production as the means by which industry can be environmentally responsible while remaining competitive and profitable.     

基于Web-GIS的黄浦江上游水源地突发水污染事故预警系统

针对黄浦江上游可能发生的突发性水污染事故,建立了油品、化学品理化性质数据库和特征流场数据库,开发了基于Web浏览器环境的突发水污染事故预警系统。通过该系统,用户可以使用Web浏览器在线模拟和统计分析突发的水污染事故,及时有效地掌握水污染现状及发展趋势,为决策者提供技术支持。该系统提供了灵活方便的操作界面,所有的空间数据分析和模拟运算全部在服务端实现,客户端只负责请求操作、模拟结果的动态显示和统计分析,便于系统的整体维护与升级。     

联合国可持续发展行动的回顾与展望

该文以时间先后为顺序,系统总结了1972年人类环境会议以来,联合国为推进全球可持续发展所采取的重要行动,对取得的进展和存在的差距进行了评述。认为,人类环境会议特别是环发大会以来,联合国为实现全球经济社会可持续发展付出了巨大的努力,在许多领域推动形成了重要的共识和多边国际公约,促进了可持续发展伙伴关系的形成与发展,加快了许多国家和地区的可持续发展行动。但是,从目前来看,所取得的进展远低于需要达到的水平,突出地体现在千年发展目标进展缓慢、环发领域谈判举步维艰、国际履约明显不足、可持续发展伙伴关系的效果并不理想等。基于这一现实,本文认为"里约+20"大会应努力在如下四个方面取得进展:一是重振里约精神,加快已有政治承诺的落实;二是在坚持里约原则的前提下,围绕气候变化等重大全球性挑战做出新的政治承诺;三是在坚持里约原则的前提下,勾画出人类绿色发展的未来蓝图;四是促进以南南合作为重点的国家合作。     

Review and Prospect of the UN Efforts for Sustainable Development

The present paper reviews the UN important efforts to promote global sustainable development in the chronological order since UN Conference on Human Environment in 1972, and analyzes the progress and gap. The results show that the UN system has made great efforts for global sustainable development since the UN Conference on Human Environment, especially since UN Conference on Environment and Development, promoted the formation of important consensus and multilateral international conventions on many fields, boosted the development of partnership in the field of sustainable development, and accelerated actions for sustainable development of many countries and regions. However, at present, the progress made is still far below the level required, prominently reflected in the slow progress toward the millen- nium development goals, the difficulties in negotiations in the field of environment and development, insufficient fulfillment of international agreements and conventions, and undesirable effects of partnership in the field of sustainable development. Based on these, the paper puts forward four suggestions for UN Conference on Sustainable Development in 2012(Rio+20):(1) to revitalize the "spirit of Rio" and accelerate the implementation of existing politi- cal commitments; (2) to make new political commitments focusing on climate change and other major global challenges under the Rio principles; (3) to lay out a blueprint of green economy under the Rio principles; and (4) to promote South-South cooperation as the focus of international cooperation.     

青藏高原东缘典型流域生态系统#br# 服务的地形梯度效应#br# ——以岷江上游为例

山地生态系统受地形因素影响在垂向上呈现出明显的空间分异特征,厘清山地生态系统服务的空间分异特征是区域土地利用和生态系统管理的基础。以青藏高原东缘典型流域岷江上游为研究区,将2000、2005、2010年土地利用数据及DEM数据作为数据源,运用地形位指数、相对变化率和敏感性系数,研究土地利用变化下的生态系统服务价值的地形梯度效应。结果表明：（1）岷江上游土地利用类型以林地和草地为主,约占总面积的60%和30%;2000～2010年,1~4级地形位上除未利用地外的其他土地利用类型分布指数变化较为明显,林地和耕地不断降低,草地、水域和建设用地不断升高。（2 ）研究期内岷江上游生态系统服务价值总量和各类型生态系统服务的价值随地形位的升高均呈倒V形变化;2000～2010年,研究区1~12级地形位上生态系统服务价值呈增加趋势,13~20级地形位上呈减小 趋势。（3）2000～2010年,各地形位上生态系统服务价值变化趋势与研究区一致;除1级地形位上生态系统服务价值变化幅度略高于研究区外,2~20级地形位上的变化幅度与研究区基本一致。（4）研究 区各土地利用类型的单位面积生态系统服务价值敏感性系数均小于1,单位面积生态系统服务价值的变化缺乏弹性,研究结果可信;2000～2010年各地形位上水域、草地和荒漠敏感性系数不断上升,林地 和耕地敏感性系数不断下降。通过对土地利用变化驱动下的生态系统服务价值的地形梯度效应进行定量测度,明晰了生态系统服务价值随地形梯度变化所呈现的空间分异规律及其变化特征,为保护区域 生态系统,合理利用土地资源提供理论依据。 关键词： 土地利用;生态系统服务;地形位指数;地形梯度;岷江上游;青藏高原东缘     

Nitrate Concentrations in Springs Flowing into the Lower Flint River Basin,Georgia U.S.A.1

Allums, Stephanie E., Stephen P. Opsahl, Stephen W. Golladay, David W. Hicks, and L. Mike Conner, 2012. Nitrate Concentrations in Springs Flowing Into the Lower Flint River Basin, Georgia U.S.A. Journal of the American Water Resources Association (JAWRA) 48(3): 423-438. DOI: 10.1111/j.1752-1688.2011.00624.x Abstract: Analysis of long-term data from (2001-2009) in four springs that discharge from the Upper Floridan aquifer into the Flint River (southwestern Georgia, United States) indicate aquifer and surface-water susceptibility to nutrient loading. Nitrate-N concentrations ranged from 1.74 to 3.30 mg/l, and exceeded historical levels reported for the Upper Floridan aquifer (0.26-1.52 mg/l). Statistical analyses suggest increasing nitrate-N concentration in groundwater discharging at the springs (n = 146 over eight years) and that nitrate-N concentration is influenced by a dynamic interaction between depth to groundwater (an indicator of regional hydrologic conditions) and land use. A one-time synoptic survey of 10 springs (6 springs in addition to the 4 previously mentioned) using stable isotopes generated δ¹⁵N-NO₃⁻ values (4.8-8.4‰ for rural springs and 7.7-13.4‰ for developed/urban springs) suggesting mixed sources (i.e., fertilizer, animal waste, and soil organic nitrogen) of nitrate-N to rural springs and predominantly animal/human waste to urban springs. These analyses indicate a direct relation between nitrate-N loading since the 1940s and intensification of agricultural and urban land use. This study demonstrates the importance of evaluating long-term impacts of land use on water quality in groundwater springs and in determining how rapidly these changes occur.     

The Transboundary Nature of the Allende–Piedras Negras Aquifer Using a Numerical Model Approach

The Allende–Piedras Negras (APN) aquifer is located between the states of Texas (United States [U.S.]) and Coahuila (Mexico). The Rio Grande crosses the aquifer, acting as a natural and political divide between the countries. However, it remains unclear whether the APN aquifer can be considered a truly transboundary aquifer flow system, which would potentially require joint management by two different administrative jurisdictions. The main purpose of this study was to evaluate the transboundary nature of this aquifer. This was achieved by developing a detailed hydrogeological model to analyze the direction of volumetric fluxes within the APN aquifer using Visual MODFLOW. The model simulated a spatially averaged cumulative drawdown of 0.76 m for the entire aquifer over an 18‐year modeling period (2000–2017). The flow convergence zone, previously located below the Rio Grande, has shifted to the U.S. side in most locations, driven by higher pumping rates of the wells located near the river. This shift of the convergence zone from one country to the other means that groundwater recharge from one side flows underneath the river to the other side. This qualifies the APN aquifer as a “transboundary groundwater flow system.” The procedure followed in this study may be applied to other aquifers that straddle the U.S.–Mexico border and may motivate future modeling studies on other poorly studied transboundary aquifers around the world and thereby enable bi‐national aquifer management.