Project Risk Screening Matrix for River Management and Restoration

The ‘project risk screening matrix’ derives from a broader effort to assist US government agency staff in reviewing proposed stream management and restoration projects more efficiently and effectively. The River Restoration Analysis Tool (RiverRAT) developed through this effort provides a thorough, comprehensive and auditable approach to review and evaluate proposed stream actions and projects ( www.restorationreview.com ). The matrix was initially developed as the first step in applying the RiverRAT, its purpose being to assist reviewers in assessing the risk to natural resources associated with a particular proposal and matching the intensity of their review to the severity of that risk. Hence, the primary application of the matrix to date has been to identify and screen out low risk projects that may be dealt with expeditiously, so freeing the time and technical resources needed to allow deep reviews of higher risk projects. A second form of screening emerged from this primary function because the matrix proved adept at identifying the minimum level of site and project characterization required to support initial risk assessment. On this basis, proposals lacking adequate information can also be screened out, being referred back to the proponent with a request for additional information. More recently, new and novel versions of the matrix, featuring modification and refinement of one or both of the original axes, have emerged to widen and refine its application to linear infrastructure (e.g. pipelines, roads, and electrical transmission lines), in‐stream structures (e.g. large wood placement and culvert removal), and pre‐application, regulatory, decision‐support tools. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.     

Can Tolerant Diatom Taxa be Used for Effective Assessments of Human Pressure?

Because lately the low bioindicative value of tolerant species from different taxonomic groups is often questioned, in this study, we hypothesized that tolerant diatoms may be used for effective temporal assessments of human pressure. We tested this on the lowland Bzura River in central Poland, on 156 diatom samples (DSs) from two study periods of 1972 with extremely severe point‐source water pollution and of 2002–2004, where the complex wastewater management in the river catchment improved water quality considerably. Out of the total 295 diatom species recorded in the samples, only 133 tolerant ones were included in the study. Patterns in their abundance were recognized with a Kohonen artificial neural network (self‐organizing map, SOM), whereas the species significantly associated with each SOM cluster of diatom samples were identified with the indicator value (IndVal) index and the Monte Carlo test. If the hypothesis tested was not supported, the assignation of DSs to the SOM clusters would be random. However, the separation of DSs from 1972 and 2002–2004 was almost perfect because the number of exceptions was as low as 4.5%. In addition, the relatively high number (64 out of 133) of tolerant species significantly associated with any SOM cluster (and respective environmental conditions at sites from which samples assigned to it come) supports the hypothesis tested. This means that almost half of the studied species are not evenly distributed in particular clusters as might be expected for highly tolerant species. The study proves that the abundances of many diatom species, currently classified as tolerant, carry quite precise information on the differences in the quality of the environment, and indicates those tolerant diatom species whose bioindicative potential may be highest. Copyright © 2014 John Wiley & Sons, Ltd.     

The potential limitations on its basin decision-making processes of granting self-defence rights to Father Rhine

ABSTRACT

Recent grants of legal rights to rivers would seem to infuse traditional anthropocentric river governance with greater eco-centrism. Through a thought experiment, we scrutinize this proposition for the Rhine basin. We consider the governance implications of granting (procedural/material) rights to the river and elaborate on their implications for the three highly institutionalized regimes of the Rhine River of water quality, flooding and transport. Since we find that a shift to more eco-centrism has already occurred and since the right granted to the river would not be absolute, we deem radical transformations unlikely.     

中小河道治理方案及思考——以上海市走马塘北岸防汛墙改建工程为例

随着城市建设的不断发展,河道环境及景观对城市市容市貌的影响也日益重要。以上海市静安区走马塘工程为例,分析中小河道环境及景观治理的措施与取得的效果,并根据工程实例对后续相关工程提出相应建议。     

Seasonal Water Level Manipulation for Flood Risk Management Influences Home‐Range Size of Common Bream Abramis brama L. in a Lowland River

The increased threat of flooding from climate change requires ever greater management of rivers to alleviate flood risk. Although the impacts of river modification on fish communities are well documented, the effects of river management practices on fish behaviour have received relatively little attention. Here, a long‐term (4 years) acoustic telemetry study was used to analyse the spatial–temporal behaviour of common bream in a lowland river system (River Witham, Lincolnshire, UK) in which water levels are artificially manipulated biannually as part of a flood storage strategy. Levels are lowered in the autumn and increased again in the spring, to increase in‐river winter flood storage capacity. Home‐range size varied according to season, with home ranges being larger in the spring and summer months in comparison with those recorded during the autumn and winter months. When water levels within the river system were artificially manipulated, the bream responded by altering their home‐range size, increasing it after the levels had been raised and reducing it following the lowering of the river levels. This is in contrast to the cumulative overall distances bream were recorded to travel, which were unaffected by water level manipulation, suggesting water level manipulation did not affect activity levels. Although such changes in behaviour do not necessarily equate to a negative impact on fitness, reduced home‐range size brought about by water level manipulation does have implications for habitat availability and the number of competitive, predatory and parasitic interactions encountered. Copyright © 2013 John Wiley & Sons, Ltd.     

桥梁工程首级控制网测量关键技术探讨

首级控制网测量是桥梁工程顺利对接的关键技术之一，为保证桥梁工程施工质量,必须建立高精度控制网。根椐国家测量规范要求,结合某桥梁工程实例，探讨了首级控制网布设过程中的布网要求,以及平面控制测量和高程控制测量的关键技术及方法。经工程检验,该控制网布测方法能有效满足工程精度要求，对类似工程具有较强的操作性和借鉴意义。