WATERSHED CLASSIFICATION USING CANONICAL CORRESPONDENCE ANALYSIS AND CLUSTERING TECHNIQUES: A CAUTIONARY NOTE1

ABSTRACT: Watershed classification using multivariate techniques requires the incorporation of continuous datasets representing controlling environmental variables. Often, out of convenience and availability rather than importance to the structure of the system being modeled, the environmental data used originate from a variety of sources and scales. To demonstrate the importance of appropriate environmental data selection, classifications of six‐digit hydrologic units (1:24,000) across selected geographic areas within the Interior Columbia River Basin were produced. Canonical correspondence analysis was used to select and test environmental variables important in predicting Rosgen stream types and valley bottom classes. Then, hierarchical agglomerative clustering was used to group (classify) watersheds based on these variables. Statistically significant results were derived from the use of organized classification data with presumed predictive relationships to watershed properties, and a random distribution of environmental variables from the same datasets provided similar results. The results contained herein demonstrate that these analysis techniques do not necessarily select meaningful variables from a broad spectrum of data and that significant results are easily generated from randomly associated data. It is suggested that classifications produced using these multivariate techniques, especially when using multi‐scale data or data of unknown significance, are subject to invalid inferences and should be used with caution.     

POTENTIAL IMPACT OF EARTHEN WASTE STORAGE STRUCTURES ON WATER RESOURCES IN IOWA1

ABSTRACT: Earthen waste storage structures (EWSS) associated with large confined (concentrated) animal feeding operations (CAFOs) were evaluated for their potential to impact water resources in Iowa. A representative sample of 34 EWSS from a digital database of 439 lagoons and basins permitted between 1987 and 1994 was analyzed. Eighteen percent (6 of 34) directly overlie alluvial aquifers that are used widely for potable water supply. Ninety‐four percent (29 of 31) were constructed below the water table based on EWSS depth data. At 65 percent of EWSS (22 of 34), 50 percent or more of the manure‐spreading area (MSA) has a water‐table depth less than 1.6 m. At 74 percent of EWSS (25 of 34), 90 percent or more of the MSA contains soil with vertical K exceeding 25.4 mm/hr. Seventy‐one percent (24 of 34) occur where 10 percent or less of the MSA is frequently flooded. No significant differences were found among leakage rates due to aquifer vulnerability class or surficial material. However, at least 50 percent of EWSS (14 of 28) leaked at rates significantly greater than 1.6 mm/d under the new construction standard. The estimated 5,000 unregulated CAFOs may have a greater potential to impact water resources in Iowa.     

INTERACTIVE DISTRIBUTED CONSERVATION PLANNING1

ABSTRACT: In the environmental and agricultural conservation planning process, more efficient and effective tools are needed for planners to assist private landowners with making wiser land use decisions. Current methods are slow, inefficient, and costly. Scientific techniques have not been fully implemented within the planning process, yet such plans are increasingly needed to meet water quality and Total Maximum Daily Load (TMDL) requirements. The objectives of this study are to (a) utilize the web for accessing an integrated science‐based land use decision support system; (b) link decision tools, models, and databases to the user via the web; (c) link distributed models and databases for enhanced planning efficiency; and (d) integrate the above into an easily usable and readily accessible system. The procedures resulting in the initial design involved planning expertise and focus groups' input. The system was developed in partnership with the Natural Resources Conservation Service of the U.S. Department of Agriculture and several state agencies. A survey of 150 certified conservation planners, the end users, was conducted to identify the data sets and planning tools needed. Data, tools, and models then were selected and integrated into a web accessible system. Specifically, the first generation used a web interactive Geographic Information System (GIS) that overlaid onto digital orthoquads and/or soils polygons field boundaries, transportation, hydrologic features (such as drains, rivers, lakes, etc.), and high pesticide risk runoff or infiltration areas. Conservation planners found they could save time with the system. Clients could access the system quickly to help them prepare for meeting with their planner. Previously acquiring GIS maps in some cases had been a lengthy process that limited use of the information in land use decisions.     

青藏铁路行车安全保障信息系统研究

分析了影响青藏铁路行车安全的主要因素 ,基于青藏铁路“快速通过高原 ,减少站点布局 ,减少定员 ,减少劳动强度”的原则 ,提出了建设青藏铁路行车安全保障信息系统的总体设计思想 ,并根据青藏铁路站点分布和自然条件情况 ,提出了青藏铁路行车安全保障信息系统及其各子系统的初步设计方案。利用现代化的传感技术、自动检测技术 ,自动采集设备的运行状态信息及环境因素信息 ,并应用先进的信息处理技术和计算机网络传输技术 ,将各种安全信息传送至调度中心和维修部门 ,实现行车事故的预测与预防     

简论灾害报警

本文运用信息论、系统论、控制论的原理，分析研究我国人民同灾害斗争的经验和教训，论述了灾害报警与人类安全的关系，灾害报警为人类安全服务的光辉历史，现代社会对灾害报警的要求，以及如何搞好灾害报警。为了防灾害于未然，达到及时报警，灾害报警的最终目标是把传感、通信和计算机联接成网，融为一体，建立现代的灾害报警网络，更好地为人类的安全服务．     

Better environmental future in Europe through environmental auditing?

environmental auditing must be rejected if the aim is to make companies introduce a specific management concept. Rather, it is preferable to leave the search for effective environmental protection strategies to the competitive system, especially since the criteria for environment-oriented management in the European Community audit proposal are without substance. Environmental auditing can, however, assume a complementary function in the framework of an overall environmental policy if it is designed as an information tool with which companies provide information on the development of environmental problems deriving from their manufacturing processes and products. However, the model required to establish a framework of quantity and evaluation criteria is not available. Further, auditing does not cover products. Similarly, there are no proposals defining the evaluation procedure for ecological resource scarcity. Thus, the attempt of the Commission of the European Communities to create the elementary prerequisites for consistent and verifiable environmental auditing in the corporate sector has failed.     

SEARCHING THE WATER RESOURCES LITERATURE: INDEXING/ABSTRACTING COVERAGE FOR LEADING WATER RESOURCES JOURNALS1

ABSTRACT: The Water Resources Scientific Information Center (WRSIC) provides comprehensive indexing/abstracting for the water resources literature. To determine in one objective way the coverage of this information service from a user's point of view, an extensive sampling of the journal literature was used to determine extent to which 10 leading water resources journals are indexed and abstracted by the system. Coverage is so high that some users will want to change toward greater use of the system.     

Aerial photographs: their use in guiding pilgrims and pointers for developing countries

The problems faced by authorities in Saudi Arabia in managing the large numbers of pilgrims visiting Muna during a brief period each year has led to experiments with aerial photography and computer techniques. This paper describes briefly the new method initiated in 1981 emphasising the remarkably short time available for information assembly and interpretation and concludes with pointers towards the development of the techniques for Third World urbanisation studies.     

Information systems and needs assessment in natural disasters: An approach for better disaster relief management

The paper addresses the issue of information in disasters relief. It begins by establishing the need for planning and systematic organization in disaster action, in order to produce a long term effect on the vulnerability levels of communities. Information is introduced as a key element in any phase of disaster management. The different informational needs are described by phases; information types and possible sources are briefly described. The organizational network of information collection is presented and the immediate need for research in this field is emphasized.     

Estimation of ammonia nitrogen load from nonpoint sources in the Xitiao River catchment, China

Ammonia nitrogen (NH4+-N) is one of the three main forms of total nitrogen (TN). Most studies have estimated the load of TN from nonpoint sources instead of one specific form. The relationship between land use and concentrations of NH4+-N in runoff was analyzed using the hydraulic analysis functions of a Geographic Information Systems (GIS), and the annual loads of NH4+-N in the Xitiao River catchment were estimated according to model results. The results suggested that the calculated annual loads of NH4+-N...