GLOBAL WATER ISSUES AND THE WORLD WATER COUNCIL1

ABSTRACT: The key events and the process that led to the creation of the World Water Council on World Water Day 1996 are reviewed and its characteristics summarized. The development of this new organization is discussed in the context of the major global trends in water and water-related issues, viz. growing water scarcity with its links to limits on food production and demographic patterns. In response to the need to find solutions to these pressing water issues, the development of a Technical Program based on the deliberations of the founding member organizations and a number of short-term activities have been outlined to demonstrate the evolution of the Council in this first year of its existence. Given the importance of complementarity between the Council and the Global Water Partnership, an attempt has been made to articulate the mutually-reinforcing roles of the two organizations.     

Ecoregions and ecodistricts: Ecological regionalizations for the Netherlands' environmental policy

For communicating data on the state of the environment to policy makers, various integrative frameworks are used, including regional integration. For this kind of integration we have developed two related ecological regionalizations, ecoregions and ecodistricts, which are two levels in a series of classifications for hierarchically nested ecosystems at different spatial scale levels. We explain the compilation of the maps from existing geographical data, demonstrating the relatively holistic, a priori integrated approach. The resulting maps are submitted to discriminant analysis to test the consistancy of the use of mapping characteristics, using data on individual abiotic ecosystem components from a national database on a 1-km² grid. This reveals that the spatial patterns of soil, groundwater, and geomorphology correspond with the ecoregion and ecodistrict maps. Differences between the original maps and maps formed by automatically reclassifying 1-km² cells with these discriminant components are found to be few. These differences are discussed against the background of the principal dilemma between deductive, a priori integrated, and inductive, a posteriori, classification.     

A first alternative for estimating the physical carrying capacities of natural areas for recreation

Utilizing an adaptation of the Universal Soil Loss Equation, this article discusses a method for approximating the physical carrying capacity of natural areas for outdoor recreation. Classification of forested woodland and field environments is based upon the conversion of ground cover coefficients to the percentage of ground cover required to maintain soil productivity over time. Four canopy types, three canopy densities, and two general types of ground cover are recognized in the equation as well as soil characteristics, topographical variations, and rainfall velocities and intensities. The method requires that the areal distribution of soils occurring within natural areas be mapped. Approximations will vary according to the intensity of the planning desired, and may range from a general classification of large land areas to highly site-specific evaluations. Data generated from over 40 years of cooperative research form the basis for classifying natural areas according to their relative physical capacities to accommodate outdoor recreation.     

THE CHUBB/BAUMAN METHOD FOR ESTIMATING THE RECREATION POTENTIAL OF RIVERS: A CRITICAL REVIEW1

ABSTRACT: The Chubb/Bauman (Ch/B) method for making quantitative estimates of recreation potential for rivers is based on the 1968/ 69 Leopold method for quantitative assessment of the scenic beauty of rivers. Both use classifications of environmental variables as the database. Unlike the Leopold method, the classifications used in the Ch/B method consistently reflect human preferences. The Ch/B method collects information on 67 variables, and uses a computer program to produce estimates of potential for 16 common recreation activities. This critique evaluates selected concepts and procedures of the Ch/B method partly by comparison with other available methods of recreation resource inventory. It considers the validity and utility of numerical weighting of variables, the use of numbers derived from place in a classification, and the transformation process. The quantitative techniques of the method exhibit serious flaws. Much of the data produced by the method appears to be quantitative but in fact is not, and it does not produce truly quantitative estimates of recreation potential. Classifications of generalized geographic or environmental variables are shown to have serious defects as a basis for evaluation of recreational potential.     

A PROBABILISTIC BENEFIT-COST ANALYSIS OF A ZONING PROGRAM FOR FLOOD PLAINS1

ABSTRACT: Various techniques, one of which is zoning, are used to control the extent of flood damage. The benefit-cost analysis of zoning programs must take into account the random nature of flooding. This paper outlines a method for determining not only the expected value of the benefit-cost ratio, but also the probability of such a zoning program being profitable. It also presents an application of the method to the assessment of the Outaouais Regional Community zoning program.     

A Multi-Channel Continuous Water Toxicity Monitoring System: Its Evaluation and Application to Water Discharged from a Power Plant

A multi-channel continuous water toxicity monitoring system was, after confirming the systems' performance, implemented to samples of water discharged from power plants to detect and classify their toxicity using several recombinant bioluminescent bacteria. Each channel of the system is composed of a series of two mini-bioreactors to enable a continuous operation, i.e., without system interruption due to highly toxic samples. A different recombinant bacterial strain was present in each channel: DPD2540 (fabA::lux CDABE), DPD2794 (recA::luxCDABE), and TV1061 (grpE::luxCDABE), which are induced by cell membrane-, DNA-, and protein-damaging agents, respectively. GC2 (lac::luxCDABE) is a constitutive strain, whose bioluminescence is reduced by an increase in cellular toxicity. Phenol and mitomycin C (MMC) were used for evaluating the system's performance to detect toxic chemicals. These samples were injected into the second mini-bioreactor according to a step or bell-curve manner. The field samples used in this study were obtained from the water discharged from two different power plants in Korea – from a nuclear power plant and a thermo-electronic power plant, and were injected into the second mini-bioreactor to initiate the toxicity test. Each channel showed specific bioluminescent (BL) response profiles due to the toxic compounds present in the water samples. Comparing the BL signals between the standard toxic chemical samples and discharged water samples, the equivalent toxicity of the field water could be estimated. Finally, it was proved that this novel continuous toxicity monitoring system can be used as an alternative tool for the quick monitoring and control of water quality, as well as aid in the setting up of a new monitoring strategy to protect the source of tap water and in the prevention of polluted water discharge.     

Automated Classification of an Environmental Sensitivity Index

Environmental Sensitivity Indices (ESI) composed of many field-data are essential for monitoring and control systems. At the beginning of the last decade an ESI of the German Wadden Sea was developed for use by the relevant authorities. This ESI was derived by experts semi-manually analysing the extensive field data-set. An algorithm is presented here which emulates human expert-decisions on the classification of sensitivity classes. This will permit the necessary regular updates of ESI-determination when new field data become available using automated classifications procedures. After tuning the algorithm parameters it generates decisions identical to those of human experts in about 97% of all locations tested. In addition, the algorithm presented also enables erroneous or extremely seldom field data to be identified.     

湖泊富营养化评价方法及分级标准

由于人类活动的影响 ,湖泊富营养化引起的环境问题日益突出。而目前现有的富营养化评价方法和分级标准混乱 ,因此有必要统一评价方法和分级标准 ,以便加强对湖泊的管理 ,保护湖泊生态环境     

可持续发展指标(体系)的分类及构建探讨

将国内外已有的可持续发展指标（体系）按学科特征归纳，分为应用经济学、生态学和统计学等３大类，分别评述其特征和不足，提出中国可持续发展指标的构建的进一步研讨，应充分开展实质性的跨学科研究，将经济发展指标的设置和选择作为重点，建立能解析可持续发展本质特征的长期性或阶段性批示指标，如生物多样性、人均维持基本生活的收入水平。     

运用能见度因子对大气稳定度参数的计算及和国标分类法的对比

分析了国际分类法的不足，引入能见度因子对大气稳定度参数进行计算，分别利用两种分类计算方法计算上海市市某气象站１９９６年逐时气象资料，再对比分析不同分类结果后，得出能见度因子对大气稳定度数的计算比国际分类法更接近实际情况。