Field and laboratory performance characteristics of a new protocol for sampling riverine macroinvertebrate assemblages

Measurement and estimation of performance characteristics (i.e. precision, bias, performance range, interferences and sensitivity) are often neglected in the development and use of biological sampling methods. However, knowledge of this information is critical in enabling potential users to assess data quality and make comparisons among different sampling methods. In this study, the performance characteristics were evaluated for both the field and laboratory components of a new large river macroinvertebrate bioassessment protocol (mLR‐BP) for non‐wadeable streams. We sampled 19 sites across two depth classes, collecting three replicate samples at each site and sorting three 300‐organism subsamples from each sample. The replicate samples provided data for estimates of precision in the laboratory and field, and abiotic variables allowed for measurements of overall sensitivity. Precision and performance range differed between shallow and deep sites, particularly for the field component. As compared with precision measured in other studies of bioassessment methods, the field component of the mLR‐BP performed similarly, particularly in shallow sites. Based on the measures of combined field and laboratory sensitivity, this protocol should be able to detect differences of approximately 20–25% in the metrics evaluated in this study, if used for bioassessment in similar types of rivers. With all sites and the field and laboratory components combined, metrics were most responsive to a gradient of urban land cover but also showed some relationship with agricultural land cover. However, metric responsiveness does not necessarily correlate with precision, and metric selection can influence the performance characteristics of the method. Overall, the sampling protocol shows great utility for bioassessment and monitoring of non‐wadeable rivers, as well as for measuring the success of restoration efforts. In addition, the design of this study provides a template for estimating performance characteristics in other non‐wadeable systems. Copyright © 2008 John Wiley & Sons, Ltd.     

流域水资源配置方法研究

流域水资源配置解决的主要问题是确定不同天然来水情况下的省际规划出境水量,以及平原地下水规划开采量和入海水量.省际规划出境水量是流域水资源管理的基础指标,平原地下水规划开采量和入海水量是反映生态状况的指标.结合严重缺水的海河流域,研究并提出采用典型年法进行水资源配置的技术路线,提出2010规划水平年满足各项控制指标条件下省际配置分区经济社会发展的可利用水量.     

THE INFLUENCE OF HYDROLOGICAL CONNECTIVITY ON FOOD WEB STRUCTURE IN FLOODPLAIN LAKES

Hydrological connectivity is an important driver of ecosystem structure in floodplain rivers; however, little is known of how hydrological connectivity affects the structure and functioning of food webs in these systems. This study examines aquatic food web structure in 10 floodplain lakes on a dryland river floodplain in eastern Australia across a connectivity gradient. Results for fishes suggest that benthic carbon sources are more important in high connectivity billabongs than in low connectivity billabongs and that pelagic sources are more important in low connectivity billabongs than in high connectivity billabongs. Fishes in less connected billabongs were also found to feed at higher trophic levels than in more connected billabongs. We hypothesize that in high connectivity billabongs, where suitable benthic primary sources are abundant, common fish species such as carp and bony bream feed as detritivores or herbivores; while in low connectivity billabongs, where benthic sources are less abundant, the same species feed as planktivores, insectivores or piscivores. This dietary difference may also be promoted by greater predation efficiency in less structurally complex low connectivity billabongs. The feeding behaviour of these fish species subsequently influences the trophic positions of fishes higher in the food chain and ultimately the total food chain lengths that high and low connectivity billabongs support. The results of this study highlight the importance of hydrological connectivity to the structure of food webs in these systems and the potential for them to be affected by water resource development. Copyright © 2011 John Wiley & Sons, Ltd.     

Measuring discontinuities in the ter river

In this paper a method for measuring discontinuities in the spatial organization of a river produced by disturbances is presented. First of all, a way of doing comparable environmental gradients defined by different variables is proposed. To do so, all the variables have been transformed by means of the equation: P_i' = P_i - P_min/P_max - P_min, as a previous measure of the parametric distances (P_ij') between sites. When these parametric distances are plotted in relation to the geographical ones, the distortion between both river images appears as an expression of the changes occurring in each stretch, and the derivative dP_ij'/dx is a measure of its rate of change. To define a river gradient, we need to calculate the general trend of a variable, using direct gradient analysis. The fit of the results obtained from an undisturbed stretch to an empirical curve for all the river gives us a measure of the expected values for that river. The difference between expected and observed values can be a measure of the discontinuity. The same procedure has been used for an overall environmental and biological data. To this end, the Euclidean distance (ED) and a distance obtained from Factor score of a Principal Components analysis (PCA) have been calculated. Only the second method seems to be of general interest for studying discontinuities. Finally, the results of the first score loadings obtained from PCA of three groups of variables (physical and chemical, physiographical and morphological, and phytobenthic) have been used to do a comparison between the parametric images of the River Ter.     

国际河流纠纷的国家责任问题

当今淡水资源日趋紧张、国际河流水资源的合理利用与管理已成为国际社会广泛关注的重要问题。笔者结合盖巴斯科夫——拉基玛洛大坝案,通过对该案的分析与总结基础上,认为：一方面,应将可持续发展原则、风险预防原则等特殊的环境法原则提升到国际法的基本原则范畴。在国家责任方面不能仅以对环境造成损害后果来作为追究责任的前提,也应该考虑对防止损害费用的补偿;另一方面,针对中国国际河流水资源的开发和利用,也提出了几点建议,以冀更好地推动我国水资源的环境保护。     

瑞士阿尔卑纳赫湖物质迁移路径研究

不断恶化的水质变化趋势需要对湖泊的水生生态进行更为广泛和深入的研究。物质的迁移和混合过程直接影响着化学和生物组分的分布，对于维系整个湖泊生态系统非常重要，理解这个复杂的过程有助于更好地保护和利用湖泊资源。为了更好地定量分析瑞士阿尔卑纳赫湖中物质的迁移路径，在研究中，用CE—QUAL—W2模型（二维）模拟物质的迁移和混合过程，与实测结果吻合良好，表明该模型较为准确地模拟了迁移和混合过程，为该模型应用于水质模拟和预测打下了坚实的基础。为了更好地反映物质的迁移过程，还采用热平衡方法计算了垂直扩散系数，并且证明单独的CTD监测能够获取可靠的垂直扩散系数，不必同时进行温度计链的监测。     

The use of remotely sensed data to detect channel hydromorphology; River Tummel,Scotland

Colour aerial photography and multi‐spectral imagery acquired from airborne platforms for the River Tummel, Scotland, was used in conjunction with field survey to assess the feasibility of monitoring hydromorphology and human alteration within the river corridor. The study was undertaken to investigate the possibility of remotely sensing the physical status of a nation's rivers at the national scale to comply with the requirement of the European Water Framework Directive. Visual assessment and unsupervised and supervised automated classifications of the imagery were undertaken and compared with field survey data. In the absence of overhanging vegetation canopies most features above the water line of interest were visible on the imagery. Below the water line, morphology and substrate composition together with bank materials on vertically cut banks are less easily detected. The overall accuracy of automated classification procedures, compared to field survey, was 60% for the colour aerial photography and 68% for the multi‐spectral imagery. Supervised classification was superior to unsupervised classification procedures. Sun glint on water surfaces and shadows caused by high banks, trees and buildings were observed as the cause of most misclassification of features. Overall, the study demonstrates that remotely sensed digital imagery has the potential to allow panoptic mapping of river hydromorphology and human impacts. The possibilities and constraints, in light of the findings of this study, are discussed. In the context of new legislation which requires environmental protection agencies to have robust tools for monitoring the physical status, as part of meeting the objective of good ecological status, of rivers across an entire nation, remote sensing appears to provide a way forward. Copyright © 2004 John Wiley & Sons, Ltd.     

九江市城区河湖水质现状及污染防治对策

水是生命之源,城市依水而建,城市河湖的水环境影响着整个城市人口的生活环境,也体现一座城市的文化品位．文章分析了九江市城区河湖的水质现状,并提出了防治对策．     

2007～2008年引江济太调水对太湖水质改善效果分析

在对引江济太调水工程前期研究的基础上,对2007年无锡供水危机事件和2008年冬春季引水中引江济太工程的作用进行了系统分析。在2007年无锡供水危机爆发1周内,随着引江济太调水工程的进行,贡湖水厂水源地溶解氧和氨氮等水质指标从劣Ⅴ类转变为Ⅲ类,小湾里水厂和锡东水厂水质也有好转;在2007年下半年和2008年上半年调水条件下,2008年5月与去年同期相比,贡湖高锰酸盐指数、总磷和总氮质量浓度分别从7.04 mg/L、0.106 mg/L、4.10 mg/L下降到3.35 mg/L、0.087 mg/L、2.87 mg/L,氨氮水质指标保持在Ⅲ类,表明引江济太调水工程对改善太湖局部湖区水质、保障太湖供水安全具有重要意义。最后提出了进一步推动引江济太调水工程长效化运行的对策措施建议。     

太湖流域水环境综合治理及其启示

总结太湖流域水环境综合治理所采取的措施和取得的效果,分析太湖流域水环境综合治理带来的启示,旨在为我国其他河湖的水环境综合治理提供参考。结果表明:1各级政府高度重视是做好流域水环境综合治理的前提;2科学规划是做好流域水环境综合治理的基础;3有效的协调机制是做好流域水环境综合治理的保障;4依法治水是做好流域水环境综合治理的保证。