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To improve the quality and success of compensatory mitigation under Clean Water Act Section 404, the U.S. Army Corps of Engineers and the U.S. Environmental Protection Agency jointly promulgated regulations in 2008. These regulations promote the use of function assessments to determine appropriate compensatory mitigation to replace functions and services lost due to permitted impacts to aquatic resources and require a watershed approach to mitigation. The Oregon Removal‐Fill law, administered by the Department of State Lands, has similar requirements. Despite higher level policy, there is a paucity of scientific focus at the practical level needed to improve the tools and practices required for regulatory program implementation to achieve better mitigation outcomes, contributing to an implementation gap. By describing key challenges and specific solutions, we share lessons from a 15‐year interagency effort to develop and implement an integrated, function, and watershed‐based stream compensatory mitigation program in Oregon. We highlight the importance of an intentional process of engagement and change management and identify outstanding science and policy needs to improve stream compensatory mitigation programs and field‐scale outcomes. [ABSTRACT FROM AUTHOR]

Monitoring of compensatory stream mitigation projects conventionally relies on spatially discrete geometric data and habitat assessments collected from representative reaches. Project success is evaluated by extrapolating site‐scale metrics such as rapid bioassessment protocol (RBP) scores and time‐series changes in width‐to‐depth ratios to adjacent reaches. For example, an excellent RBP score at one location is used to infer excellent habitat in nearby reaches. This paper compares spatially discrete and continuous monitoring data from 38 km of restored stream length on a stream mitigation project in central Kentucky to document how conventional site‐level metrics may not represent conditions in adjacent reaches, particularly on projects plagued by post‐construction geomorphic instability (e.g., headcut migration, propagation of bank erosion, and chute cutoff formation). Over a 5‐year monitoring period, rapid visual assessment walkabouts documented project‐scale geomorphic process trajectories that were not captured by conventional site‐specific monitoring. Early detection of geomorphic instability from this rapid monitoring approach facilitated cost‐effective and tailored adaptive management (e.g., planting of live stakes to arrest bank erosion). Full‐census walkabouts can thereby help to improve mitigation credit valuation, enhance long‐term habitat protection, and facilitate successful steam restoration outcomes. [ABSTRACT FROM AUTHOR]

Context: Land use in a catchment area is critical to understanding how human activities are impacting streams. Catchment land cover is typically quantified as proportions of land use types, but such proportions do not quantify where land use patches are relative to the stream. Objectives: This paper discusses the merit of land use position metrics for application to stream assessments. Methods and results: Landscape configuration metrics (LCMs) are often used in stream assessments to describe land use position, but we argue these metrics should be avoided due to: (1) poor description of catchment land cover; (2) inconsistency, and; (3) missing link between valley and stream. Inverse-distance-weighted metrics (IDWs) explicitly quantify the position of land use patches relative to the stream, and thus are conceptually grounded in empirical evidence that the effect of land use is inversely related to its distance from the stream. Hydrologically active IDWs (HA-IDWs) further refine IDWs by quantifying the proximity of land use to hydrologic pathways connecting a stream to its catchment. Conclusions: We recommend IDW metrics become the standard method to describe catchment land use and its effect on stream conditions and that HA-IDW metrics be used when the required data is available. [ABSTRACT FROM AUTHOR]

Despite geomorphic processes being increasingly recognized as a vital component of river management projects, evidence suggests that they may not be adequately captured in common river assessment procedures. We reviewed 91 river assessment procedures from around the world to evaluate their effectiveness in capturing geomorphic processes relevant for river management goals. Our objectives were to summarize which common geomorphic indicators are measured and how in different types of river assessments categorized based on their main focus: geomorphic, physical habitat, mixed geomorphic and habitat, and hydromorphology. Our analysis identified differences in the types of geomorphic indicators included and measurement methodologies between the types of assessment procedures. Some geomorphic processes, such as sediment transport, are nearly completely absent from all assessments, despite their importance for geomorphic processes. The variability among assessment procedures suggests that a single procedure is unlikely to capture all geomorphic components required to support every river management programs. Here, we discuss how the strengths and limitations of different assessment types can be used to guide decisions around how to select assessments and geomorphic indicators to support management project goals. A companion paper expands the discussion of how to plan effective river assessment procedures to support unique management goals. [ABSTRACT FROM AUTHOR]

Fluvial geomorphology, which describes the form and processes of rivers, is increasingly being incorporated into river assessment procedures. However, the complexity of geomorphic processes makes a single universal and standardized assessment protocol a challenging and possibly impractical task. In this paper, we present a set of recommendations for choosing appropriate river assessment procedures and measuring geomorphic indicators to effectively capture important geomorphic processes required to support river management goals. We outline steps for building a river assessment procedure based on an adaptive approach rather than a one‐size‐fits‐all approach, where the geomorphic indicators, spatial and temporal scale, and methodologies used are carefully chosen based on the goals of the management project; the assessment aims to support. Guidance for choosing the appropriate geomorphic indicators is based on their significance (usefulness in characterizing the system), ease of measurement, and temporal scale needs. We also present recommendations on measurement techniques for each indicator while highlighting recent technological and methodological advancements that help overcome resource challenges often faced in river assessment. Given the wealth of scientific and technological developments in the field of geomorphology, it is possible to improve how geomorphic form and function are measured and incorporated into river assessments that support watershed management goals. [ABSTRACT FROM AUTHOR]

New methods are required for biomonitoring of poorly known tropical ecosystems, but biological assessments of environmental status are limited by insufficient information on taxonomy, composition and ecology of local communities. The current work applies DNA‐based assessment to establish the impact of various types of anthropogenic disturbances on the freshwater macroinvertebrates in an understudied biodiversity hotspot in South Asia, an area that attracts increasing attention for the loss of aquatic ecosystems.We sampled 16 river systems in the Chittagong Hill Tracts region of Bangladesh and characterised habitat intactness based on a set of 14 environmental parameters associated with habitat quality and human activities. Whole‐community metabarcoding was used to investigate the distribution of hypothetical species‐level clusters (Operational Taxonomic Units, OTUs) across sites of different impacts.We found >900 DNA clusters of insects, decapods and molluscs, dominated by Diptera, which revealed significant variation (p < 0.001) in richness across sites. The presumed sensitive Ephemeroptera‐Plecoptera–Trichoptera (EPT) represented 15.6% of total OTU richness. The type and strength of anthropogenic stressors varied greatly across streams but did not affect total OTU diversity. In contrast, EPT richness decreased by ~50% in response to habitat degradation. Partial‐network analysis revealed 26 OTUs that may serve as potential indicators for either good or poor ecological status. Overall, our results document high diversity, local endemicity and pronounced responses to disturbance in these largely unexplored but threatened habitats.Synthesis and applications. The proposed methodology combines local habitat surveys across sites of various degrees of disturbance with species‐level metabarcoding, as a model for biological evaluation of water bodies in poorly known and inaccessible places across the world. Implemented here for the Indo‐Burmese hotspot, the approach will have great value for applied conservation management as a step towards building a biomonitoring system in this region where currently little is known about the taxonomy, diversity and endemicity in both intact and disturbed ecosystems. [ABSTRACT FROM AUTHOR]

This study aims to develop a benthic macroinvertebrate multimetric index for assessing the ecological quality of streams in Northeastern Thailand. ANOSIM indicated that the benthic macroinvertebrate assemblage in both of each basin and each season were not significantly different (R = 0.09, p = 0.24 and R = 0.07, p = 0.35, respectively). The efficacy metrics of each basin consisting of the Mekong II, the Chi, and the Mun basins were integrated and calibrated. A total of 255 data sets of water physico-chemical and benthic macroinvertebrates during the dry period (cool and hot seasons) were obtained. The stream classification could be divided into three groups: the reference group (48 stations), the stressed group (42 stations), and the intermediate group (165 stations). Twelve out of 56 metrics have been considered as a core metric for the development of a biological index for quality streams in the Northeast, including Total taxa, EPT taxa, Ephemeroptera taxa, Coleoptera taxa, % EPT, % Chironomidae, % Tolerant individuals, % Intolerant individuals, Beck's index, HBI, Predator taxa, and Clinger taxa. Moreover, this metric set covered the structure and function of organisms including the diversity of species, community structure, tolerance/intolerance measures, functional feeding group, and habit. From the efficacy validation of the biological index, the results of stream assessment corresponded to the classification sites with the physico-chemical characteristics.

Instream wood promotes habitat heterogeneity through its influence on flow hydraulics and channel geomorphology. Within the Columbia River Basin, USA, wood is vital for the creation and maintenance of habitat for threatened salmonids. However, our understanding of the relative roles of the climatic, geomorphic, and ecological processes that source wood to streams is limited, making it difficult to identify baseline predictions of instream wood and create targets for stream restoration. Here, we investigate how instream wood frequency and volume differ between seven sub-basins of the interior Columbia River Basin and what processes shape these differences within these sub-basins. We collected data on wood volume and frequency, discharge and stream power, and riparian and watershed forest structure for use in modelling wood volume and frequency. Using random forest models, we found that mean annual precipitation, riparian tree cover, and the individual watershed were the most important predictors of wood volume and frequency. Within sub-basins, we used linear models, finding that some basins had unique predictors of wood. Discharge, watershed area, or precipitation often combined with forest cover, riparian conifer, and/or large tree cover in models of instream large wood volume and frequency. In many sub-basins, models showed at least one hydrologic variable, indicative of transport competence and one ecological variable, indicative of the reach or upstream watershed's capability to grow measurable instream wood. We conclude that basin-specific models yield important insights into the hydrologic and ecological processes that influence wood loads, creating tractable hypotheses for building predictive models of instream wood. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary Stream-habitat assessment for evaluation of restoration projects requires the examination of many parameters, both watershed-scale and reach-scale, to incorporate the complex non-linear effects of geomorphic, riparian, watershed and hydrologic factors on aquatic ecosystems. Rapid geomorphic assessment tools used by many jurisdictions to assess natural channel design projects seldom include watershed-level parameters, which have been shown to have a significant effect on benthic habitat in stream systems. In this study, Artificial Neural Network (ANN) models were developed to integrate complex non-linear relationships between the aquatic ecosystem health indices and key watershed-scale and reach-scale parameters. Physical stream parameters, based on QHEI parameters, and watershed characteristics data were collected at 112 sites on 62 stream systems located in Southern Ontario. Benthic data were collected separately and benthic invertebrate summary indices, specifically Hilsenhoff’s Biotic Index (HBI) and Richness, were determined. The ANN models were trained on the randomly selected 3/4 of the dataset of 112 streams in Ontario, Canada and validated on the remaining 1/4. The R 2 values for the developed ANN model predictions were 0.86 for HBI and 0.92 for Richness. Sensitivity analysis of the trained ANN models revealed that Richness was directly proportional to Erosion and Riparian Width and inversely proportional to Floodplain Quality and Substrate parameters. HBI was directly proportional to Velocity Types and Erosion and inversely proportional to Substrate, % Treed and 1:2 Year Flood Flow parameters. The ANN models can be useful tools for watershed managers in stream assessment and restoration projects by allowing consideration of watershed properties in the stream assessment. [ABSTRACT FROM AUTHOR]

The Stream Performance Assessment ( SPA), a new rapid assessment method, was applied to 93 restored, 21 impaired, 29 reference, and 13 reference streams with some incision throughout North Carolina. Principal component analysis ( PCA) indicated restored streams align more closely with reference streams rather than impaired streams. Further, PCA-based factor analysis revealed restored streams were similar to reference streams in terms of morphologic condition, but exhibited a greater range of scores relative to aquatic habitat and bedform. Macroinvertebrate sampling and GIS watershed analyses were conducted on 84 restored streams. SPA and watershed data were compared to Ephemeroptera, Plecoptera, and Trichoptera ( EPT) taxa to determine which factors indicate stream health. SPA and watershed factors were used in least squares, ridge, and principal component regression ( PCR) to develop a prediction model for EPT taxa. All three methods produced reasonable predictions for EPT taxa. Cross-validation indicated ridge regression resulted in the lowest prediction error. The ridge model was then used to predict EPT taxa numbers for 21 impaired and 25 reference streams in addition to the 84 restored streams. Statistical comparisons of the predicted scores indicated urban streams (>10% impervious watershed cover) have lower expected numbers of EPT taxa. Rural restored streams have macroinvertebrate metric scores similar to those predicted for rural reference streams. [ABSTRACT FROM AUTHOR]

Highlights: [•] Data from multiple agencies were able to be aggregated and used for bioassessment. [•] Replicate samples showed high variability depending on index. [•] Indices were moderately correlated however varied in overall watershed assessment. [•] Locally calibrated index classified sites as higher condition than regional indices. [•] 10 years of monitoring may be required to reveal long-term natural variability. [Copyright &y& Elsevier]

Abstract: Assessment of stream ecosystem ‘health’ traditionally uses structural indicators (e.g., invertebrate community composition) but often neglects indicators of ecosystem processes (e.g., decomposition rates), providing an incomplete picture of overall ecosystem condition. Given a lack of standardized process-based indicators, we present a protocol for measuring organic-matter decomposition, represented by the breakdown of cellulose in the form of woven cotton fabric. The material, used more conventionally as artists’ fabric, has been suggested as a replacement for a standard cotton material (Shirley Burial Test Fabric) that had been widely used in decomposition studies for decades but is no longer manufactured. In field trials, we incubated cotton strips made of artists’ fabric in 49 streams in the Midwest (USA), northern Michigan (USA), and in New Zealand to: (1) test the assay under field conditions, (2) provide an initial population of data to which future studies can be compared, and (3) assess some environmental conditions that might influence cotton-strip decay. Decomposition of the strips, as loss of tensile strength, differed among regions and, in some cases, among streams within regions, suggesting that the assay is sensitive to differences in environmental conditions at regional and watershed scales. Mean rates (and standard deviation) of tensile-strength loss across streams of tensile-strength loss were 2.3%/d (0.4), 1.8%/d (0.7), and 1.5%/d (1.0) for the midwestern, Michigan, and New Zealand streams, and 1.7%/d (0.8) overall. Principal components analysis indicated that stream water ammonium and soluble reactive phosphorus explained a small but significant amount of variation (R 2 =0.12) in tensile-strength loss among streams. Rates of respiration of cotton strips incubated in Michigan streams were positively related to tensile-strength loss (R 2 =0.70). When streams were classified by substrate size, cotton-strip tensile strength (but not respiration) differed among substrate size classes. We conclude that a cotton-strip assay based on the artists’ fabric holds promise for replacing the assay based on the Shirley material, and as a process-based indicator for assessing the condition of stream ecosystems. [Copyright &y& Elsevier]

ABSTRACT As urban development increases, a need is emerging to understand and predict river behaviour in order to focus rehabilitation efforts and protect the natural river system while preserving urban infrastructure. Stream assessment methods are reviewed to demonstrate the need for a physically based and objective method that is also accessible in terms of time, data requirements and expertise. The case of Highland Creek near Toronto, Canada, is used to demonstrate a new type of initial stream assessment method that is based on the concept of stream power and performed entirely in a geographic information system using information from a digital elevation model (DEM). The results from this analysis are tested against existing information for Highland Creek. This includes a hydraulic model (Hydraulic Engineering Center's 'River Analysis System'), field-measured slopes, air photos and the geomorphic effects of an extreme flood. In addition, the results are presented in map form to demonstrate the effectiveness of visualizing the stream-power distribution over the entire basin and also the usefulness of overlaying stream power onto other available information. The slopes extracted from the DEM are found to be statistically similar to those from a one-dimensional hydraulic model and field-measured slopes. Individual peaks in slope as well as locations of stream-power maxima and minima are found to correlate to actual channel features as seen in air photos. The extreme flood event of August 2005 caused a dramatic change in channel form at the exact location of maximum energy predicted by the DEM-based stream-power analysis. The case of Highland Creek illustrates how this approach yields a useful outcome for understanding stream dynamics and stability as part of a stream assessment process. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Ecosystems have become a primary focus for conservation efforts seeking to maintain native freshwater biodiversity. Inherent in lotic ecosystem studies is consideration of the influences that multiscale environmental properties have on the state of biological communities and ecological processes, herein referred to more generally as stream integrity. The Watershed Habitat Evaluation and Biotic Integrity Protocol (WHEBIP) was developed to provide rapid assessment of stream integrity for stream segments throughout watersheds based on riparian and subbasin features interpreted principally from aerial imagery and topographic maps. Protocol calibration was based on relationships between WHEBIP scores and aquatic community and aquatic habitat field data collected in the French Creek watershed, Chautauqua County, NY, USA. A test of the protocol in the Cussewago Creek watershed, Crawford and Erie Counties, PA, USA, indicated that the WHEBIP can be used as a generalized-stream integrity rapid-assessment tool, especially related to fish communities. However, the protocol's ability to predict stream macroinvertebrate biological integrity measures was limited, emphasizing that it should be used primarily as a stratification tool to guide the classification of stream integrity within watersheds. [ABSTRACT FROM AUTHOR]

Abstract: Large wood in streams can play an extraordinarily important role in influencing the physical structure of streams and in providing habitat for aquatic organisms. Since wood is continually lost from streams, predicting the future input of wood to streams from riparian forests is crucial to assessing or managing stream ecosystems. Unfortunately, regional monitoring protocols have no established capacity to provide this information. The goal of this research is to propose one or more methods that could meet this need. This goal is pursued by using stream wood delivery models to aid in the design of a monitoring method. Two questions are asked. First, does simpler data change model predictions of future contributions of wood from riparian ecosystems to the stream? The answers to this first question enable monitoring design to be tailored to details affecting estimates of future stream condition. These answers are important, because more detailed data is typically more costly. Second, which metrics, if any, correlate well with model predictions? If such metrics can be identified, then these measures can serve as effective indicators of ecosystem function directly, without using ecosystem models. These questions were addressed by collecting highly detailed field observations of riparian forests from 109 forested riparian sites in the Coast Range, Willamette Valley, and western Cascades of northwestern Oregon. Detailed and simplified versions of these data were used in models that forecast the potential of riparian forests to provide wood to the stream. Model predictions with less detailed data typically provided answers different than did predictions made with more detailed data. Thus, ecosystem assessments requiring these types of model predictions would benefit from more detailed data. In contrast, riparian metrics easily observed in the field (e.g. number of basal area of trees) or derived from remotely sensed imagery (e.g. number or height of canopy trees) were well correlated with model predictions of potential stream wood recruitment. When direct model predictions or model scenario analyses are not required, these metrics can serve as effective indicators of the potential of riparian forests to provide wood to the future stream network. [Copyright &y& Elsevier]

The Wisconsin Department of Natural Resources (WDNR), with support from the U.S. EPA, conducted an assessment of wadeable streams in the Driftless Area ecoregion in western Wisconsin using a probabilistic sampling design. This ecoregion encompasses 20% of Wisconsin’s land area and contains 8,800 miles of perennial streams. Randomly-selected stream sites ( n = 60) equally distributed among stream orders 1–4 were sampled. Watershed land use, riparian and in-stream habitat, water chemistry, macroinvertebrate, and fish assemblage data were collected at each true random site and an associated “modified-random” site on each stream that was accessed via a road crossing nearest to the true random site. Targeted least-disturbed reference sites ( n = 22) were also sampled to develop reference conditions for various physical, chemical, and biological measures. Cumulative distribution function plots of various measures collected at the true random sites evaluated with reference condition thresholds, indicate that high proportions of the random sites (and by inference the entire Driftless Area wadeable stream population) show some level of degradation. Study results show no statistically significant differences between the true random and modified-random sample sites for any of the nine physical habitat, 11 water chemistry, seven macroinvertebrate, or eight fish metrics analyzed. In Wisconsin’s Driftless Area, 79% of wadeable stream lengths were accessible via road crossings. While further evaluation of the statistical rigor of using a modified-random sampling design is warranted, sampling randomly-selected stream sites accessed via the nearest road crossing may provide a more economical way to apply probabilistic sampling in stream monitoring programs. [ABSTRACT FROM AUTHOR]

Objective assessment of habitat compensation is a central yet challenging issue for restoration ecologists. In 1997, a 3.4-km stream channel, designed to divert water around an open pit diamond mine, was excavated in the Barrenlands region of the Canadian Arctic to create productive stream habitat. We evaluated the initial success of this compensation program by comparing multiple biological attributes of the constructed stream during its first three years to those of natural reference streams in the area. The riparian zone of the constructed stream was largely devoid of vegetation throughout the period, in contrast to the densely vegetated zones of reference streams. The constructed stream also contained lower amounts of woody debris, coarse particulate organic matter (CPOM), and epilithon; had lower coverage by macrophytes and bryophytes; and processed leaf litter at a lower rate than reference streams. Species richness and densities of macroinvertebrates were consistently lower in the constructed stream compared to natural streams. This contributed to differences in macroinvertebrate assemblage structure throughout the period, although assemblages showed some convergence by year 3. The effectiveness of the constructed stream to emulate natural streams varied somewhat depending on the biological attribute being evaluated. Assessments based on individual attributes showed that minimal to moderate levels of similarity between the constructed stream and natural streams were achieved. A collective assessment of all biological and ecosystem attributes suggested that the constructed stream was not a good surrogate for natural streams during these first years. Additional time would be required before many characteristics of the constructed stream would resemble those of reference streams. Because initial efforts to improve fish habitat in the constructed stream focused on physical structures (e.g., weirs, vanes, rock, groins), ecologic factors limiting fish growth... [ABSTRACT FROM AUTHOR]

Most surveys of large wood in streams are conducted by counting and measuring every piece of large wood within a reach, a technique that is effective but time-consuming. In this study we evaluated an alternative method that takes less time and can be employed in studies in which an estimate of total large wood volume along a stream reach is the primary metric of interest. In first- through third-order streams we estimated in-stream large wood volume and large wood frequency, comparing large wood census estimates to those from a modified a line-intercept technique that has been commonly used in terrestrial forest surveys. Estimates of large wood volume from line transects located in the geographic center of the stream (parallel to stream axis and equidistant from bankfull margins) were highly correlated with those from the wood census ( P < 0.001, r 2 = 0.88, Pearson’s r = 0.935), but produced slightly greater estimates of large wood volume (regression slope = 1.28, SE = 0.16). Line-intercept estimates of large wood frequency (number per 100 m of stream) were significantly correlated to the wood census counts, but the line-intercept method underestimated frequency by about 50% ( P = 0.016). Differences in the estimated large wood volume between line-intercept and wood census surveys were associated with variability in the diameter of the large wood, but unrelated to stream bankfull width, for the range of stream sizes evaluated in this study (≈ 2 to 11 m). Our results suggest that in small constrained streams, line-intercept surveys are an effective method for estimating in-stream large wood volume and that these estimates better approximate results from whole-stream census techniques where the diameter of in-stream wood is relatively consistent. [ABSTRACT FROM AUTHOR]

Abstract: In the STAR/AQEM protocol microhabitats covering less than 5% of the sampling area were neglected. Driven by an ongoing discussion on the importance of these underrepresented microhabitats we tested the influence of sampling them. We investigated 48 streams representing 14 different stream types from all over Germany. Macroinvertebrates of underrepresented microhabitats were sampled in addition to the STAR/AQEM protocol. To ensure the method remains feasible in routine monitoring programmes the total sampling and sorting effort of additional sampling was limited to 20min. Particularly those taxa were picked, which were not recognised during the routine STAR/AQEM sorting. To identify the effect of additional sampling on stream assessment results, we calculated the stream type-specific Multimetric Index (MMI) with the “main” and the “main+additional” data for each sample. The mean and median difference in MMI values between “main” and “main+additional” samples was 0.02 and 0.01, respectively. In seven of 48 samples (14.6%) a different ecological quality class was calculated with the “main+additional” dataset. Regarding common metrics within the MMI as well as intercalibration metrics differences between “main” and “main+additional” samples were analysed. The values differed most in richness metrics (e.g., number of EPTCBO Taxa, number of Trichoptera Taxa). The results of the present study show that additional sampling of underrepresented microhabitats could alter multimetric assessment results. [Copyright &y& Elsevier]

The Bird Integrity Index (BII) presented here uses bird assemblage information to assess human impacts to 28 stream reaches in the Blue Mountains of eastern Oregon. Eighty-one candidate metrics were extracted from bird survey data for testing. The metrics represented aspects of bird taxonomic richness, tolerance or intolerance to human disturbance, dietary preferences, foraging techniques, and nesting strategies that were expected to be positively or negatively affected by human activities in the region. To evaluate the responsiveness of each metric, it was plotted against an index of reach and watershed disturbance that included attributes of land use/land cover, road density, riparian cover, mining impacts, and percent area in clearcut and partial-cut logging. Nine of the 81 candidate bird metrics remained after eliminating unresponsive and highly correlated metrics. Individual metric scores ranged from 0 to 10, and BII scores varied between 0 and 100. BII scores varied from 78.6 for a minimally disturbed, reference stream reach to 30.4 for the most highly disturbed stream reach. The BII responded clearly to varying riparian conditions and to the cumulative effects of disturbances, such as logging, grazing, and mining, which are common in the mountains of eastern Oregon. This BII for eastern Oregon was compared to an earlier BII developed for the agricultural and urban disturbance regime of the Willamette Valley in western Oregon. The BII presented here was sensitive enough to distinguish differences in condition among stream riparian zones with disturbances that were not as obvious or irreversible as those in the agricultural/urban conditions of western Oregon. [ABSTRACT FROM AUTHOR]

Abstract: Stream benthic macroinvertebrates are useful indicators of the impacts of disturbances on catchment and stream conditions because they integrate many catchment-scale ecological processes. We tested the ability of macroinvertebrate assemblages over a 3-year period to indicate the impacts of a range of disturbances resulting from military training at the Fort Benning Military Installation, Georgia. We studied seven small streams that drained catchments spanning disturbances that ranged from light infantry movements to heavy disturbances from tracked vehicle movements. The main disturbance to streams was influx of sediment associated with training and use of unpaved roads. We quantified disturbance level as the % of catchment occurring as bare ground on slopes >3% and as unpaved road cover. Disturbance level values ranged from about 3 to 15%. Nonmetric multidimensional scaling ordinations revealed macroinvertebrate assemblages were associated with catchment disturbance. Irrespective of season, several richness measures (e.g., number of Ephemeroptera, Plecoptera, and Trichoptera taxa and richness of Chironomidae) negatively corresponded with catchment disturbance, however except for chironomid richness all measures showed high variation among seasons and annually. Compositional and functional feeding group measures also showed high seasonal and annual variation, with only the % of macroinvertebrates clinging to benthic habitats (=% clingers) corresponding with disturbance. Both tolerance metrics tested, the Florida index and North Carolina biotic index, showed little seasonal and annual variation, however only the Florida index related to disturbance. A regional multimetric, the Georgia stream condition index, consistently corresponded with catchment disturbance and showed the least temporal variability. Our results further suggest a threshold at 8–10% of the catchment as bare ground and unpaved road cover, a disturbance threshold similar to that reported for other land uses. [Copyright &y& Elsevier]

Little is known about the importance of landscape and land cover to the implementation and performance of agricultural conservation projects designed to improve stream quality. In our study, we addressed the potential importance of landscape and land cover to conservation projects by measuring variation across 191 μ-basins (100–2400 ha) and integrating the observed variation into a study design aimed at determining the effectiveness of conservation projects. Our findings indicate that there are strong gradients across which landscape and land cover attributes vary. Land cover varied along a gradient of agricultural intensity, basin morphometry across gradients of stream closure and basin size, basin substrate was described by variation in drumlin formation, glacial landform type, and soil drainage, while agricultural conservation projects varied according to the level of project implementation. Correlation of these gradients found several associations between landscape and land cover, indicating that agricultural intensity was being constrained predominantly by drumlin formation and glacial landform type. Landscape and land cover did not appear to be determining factors in the implementation of conservation projects by land owners. Based on these findings we chose 32 μ-basins which represented the variability along each of the defined gradients for further study. We conclude that landscape scale variables demonstrate important variation and covariation that can and should be integrated into study designs for the assessment of streams and human activities affecting streams. [ABSTRACT FROM AUTHOR]

Abstract: The main aim of the study was to develop a multimetric assessment system for macroinvertebrate communities of small and mid-sized streams in Germany in accordance with the Water Framework Directive of the European Union. The system should be applicable by water authorities, capable of distinguishing between different impacts, and specifically adapted to all types of small and mid-sized rivers in Germany. An assessment system has been developed consisting of two modules based on the established indices for saprobic degradation and acidity, and a third module covering general degradation. For the third module a new multimetric index (MMI) was developed and tested using preclassifications for stream hydromorphological degradation, land use and general impairment as impact measures. More information on sampling method, season and the type of dominating human impairment allowed to further analyse the index'' capabilities and sensitivity. It performed well in all seasons and detected all types of impairment except acidity. The usefulness of the impact measures used in this study is discussed with regard to the development of a multimetric index. The comparison of the new index with other indices showed that it is especially sensitive in detecting macroinvertebrate community responses to hydromorphological degradation and pollution such as the German AQEM index, while IBI 12 and Renkonen''s similarity more reflect general community shifts caused by any type of disturbance. The new assessment system will be proposed for future use by state agencies for nationwide monitoring in the context of the Water Framework Directive implementation. [Copyright &y& Elsevier]

Abstract: The process of selecting invertebrate-based candidate metrics for the German stream assessment system is described. The aim was to identify metrics indicating degradation types other than organic pollution and acidification (“general degradation”). For 18 out of 24 German stream types a data base of roughly 2,000 benthic invertebrate samples was generated; for each sample 79 metrics were calculated. Data on land use in the catchment were compiled for all sampling sites, together with data on hydromorphology for many sampling sites. Hydromorphological and land use parameters, which describe a clear gradient in the data sets were identified by Non-metric Multidimensional Scaling (NMS). Correlation analyses between land use/hydromorphological parameters and metric results were calculated separately for the individual stream types. Among those metrics best indicating catchment- and hydromorphological degradation in the majority of stream types are: proportion of Ephemeroptera, Plecoptera and Trichoptera; proportion of Plecoptera (mainly suited for mountain streams); number of Plecoptera taxa; proportion of xenosaprobic taxa; proportion of epirhithral preferring taxa. Differences of metric correlations between stream types and between degradation types are discussed, leading to a list of candidate metrics for assessing German streams. [Copyright &y& Elsevier]

Abstract: With the aim of finding an efficient, standardised and practical protocol for sorting macroinvertebrate samples for water management practice, three different sorting techniques were tested: RIVPACS sorting, a modified AQEM/STAR (MAS) sorting protocol and a Live-sorting method. Based on the same AQEM/STAR sample to ensure comparable results, we compared RIVPACS and MAS sorting for 20 samples, and Live-sorting and MAS for a different set of 20 samples. Comparisons were based on both ecological and financial parameters relevant for the implementation of the EU Water Framework Directive in Germany. Parameters include recently developed multimetric assessment indices, their stream type specific core metric results, time effort and costs. While RIVPACS and MAS sorting produced similar results in terms of ecological assessment, time effort and costs, Live-sorting differed notably in all three respects. Live-sorting is the quickest and least expensive protocol, but shows higher variability than the other protocols. We discuss the differences and the level of standardisation for each of these methods. [Copyright &y& Elsevier]

Abstract: In the past, no single standardised method for sampling and sorting benthic macroinvertebrates has been implemented in Germany. Therefore, we tested the suitability of two common sorting protocols, RIVPACS and AQEM/STAR, by taking samples with each protocol at 44 sampling sites. Our results reveal that different methods deliver slightly different assessment results. Moreover these two methods differ in costs. Although the AQEM/STAR protocol takes longer than the RIVPACS protocol, we favoured the AQEM/STAR protocol because of its higher level of standardisation. In order to limit costs to an acceptable level, a modification of the AQEM/STAR protocol (MAS method) is developed. This method is highly standardised, gives stable assessment results and is relatively inexpensive (€ 224.00 for processing of an average sample). A detailed protocol of the newly developed method is given. [Copyright &y& Elsevier]

Solar exposure profoundly affects stream processes and species composition. Despite this, prominent stream monitoring protocols focus on canopy closure (obstruction of the sky as a whole) rather than on measures of solar exposure or shading. We identify a candidate set of solar exposure metrics that can be derived from hemispheric images. These metrics enable a more mechanistic evaluation of solar exposure than can be achieved with canopy closure metrics. Data collected from 31 stream reaches in eastern Oregon enable us to quantify and compare metrics of solar exposure from hemispheric images and a metric of canopy closure with a concave densiometer. Repeatability of hemispheric metrics is generally as good as or better than the densiometer closure metric, and variation in the analysis of hemispheric images attributable to differences between analysts is negligibly small. Metrics from the hemispheric images and the densiometer are typically strongly correlated, at the scale of an individual observation and for 150 m stream reaches, but not always in a linear fashion. We quantify the character of the uncertainty in the relationship between the densiometer and the hemispheric metrics. Hemispheric imagery produces repeatable metrics representing an important ecological attribute; thus those researching the effects of solar exposure on stream ecosystems should consider the use of hemispheric imagery. [ABSTRACT FROM AUTHOR]

Application of a sentinel species-based population evaluation using creek chub (Semotilus atromaculatus), a common minnow in eastern North America, could provide a framework for environmental assessments and focus future research in small streams. Analysis of creek chub endpoints (growth, condition, fecundity) was based on an assessment framework for white sucker (Catostomus commersoni) populations (Gibbons & Munkittrick, 1994). We evaluated creek chub and fish community endpoints simultaneously in two streams with differing degrees of urbanization, agriculture, and thermal regimes during spring, summer, and fall. Fish from the more altered stream appear to be suffering from a feeding-based niche shift, and demonstrate reproductive anomalies suggestive of exposure to some unknown sublethal stressor(s). Fish community assessments identified modified habitat and water quality but did not detect the presence of any additional stressor(s). Similarity in fish community and population responses, widespread distribution of creek chub, limited within-stream movements, and the ability of this species to populate even the smallest streams where the resident fish community may be depauperate and fish community-type assessments limited, makes the potential use of creek chub as a monitor for small streams promising over a wide geographic zone. [ABSTRACT FROM AUTHOR]

• Assessment of hydrochemistry and its spatio-seasonal variations in the Jhelum River Basin. • Hydrochemistry is controlled by anthropogenic, lithogenic and gradient factors. • Water quality towards downstream segments poses safety concern for drinking purpose. • Total coliform bacteria and pH are main contributors to WQI evaluation. The characterization and evaluation of water quality in the Jhelum River Basin is indispensable due to its immense significance in supporting the livelihoods of people and various ecosystem services. Anthropogenic pressures, however, in the form of forest degradation, reckless use of fertilizers and pesticides, land system changes and unplanned settlements are diminishing pristine basin water quality, which necessitates better understanding of pollution variability and its sources. Extensive field sampling across major tributaries and along main river course was carried out during the year 2017–18. Pattern recognition techniques like Hierarchical Cluster Analysis (HCA), Wilk's λ quotient, Principal Component Analysis (PCA) and Analysis of Variance (ANOVA) were applied to a huge dataset comprising of 5192 observations. Spatially, three clusters correspond to low pollution headwater streams (cluster 1), moderately polluted middle and downstream sites (cluster 2) and high polluted main river course sites (cluster 3). This is also supported by ANOVA results, manifesting significantly higher concentrations of total hardness (TH), calcium (Ca), magnesium (Mg), chloride (Cl), total alkalinity (TA), nitrate-nitrogen (NO 3 -N), total phosphorus (TP), iron (Fe) and total coliform (TC) in high pollution associated cluster (cluster 3) followed by cluster 2 and minimum quantities were observed in cluster 1. Observations on seasonal water quality either did not fluctuate considerably or differs significantly during summers only, except water temperature (WT), which exhibits significant difference in all seasonal clusters. Wilk's λ quotient distribution revealed that only WT was main contributor in the formation of seasonal clusters. PCA recognized five underlying factors in the data structure and explained about 72% of total variance. Maximum variance (22.66%) is explained by combination of ionic salt group (natural source) and TC (anthropogenic source) followed by dissolved ions (19.20%) causing hardness and buffering of waters, nutrient sources (15.08%) from human and agriculture wastes, gradient factor (7.87%) allied with small fall in dissolved oxygen (DO) downwards and pH (7.11%) linked with hydrolysis of acidic material accrued from organic matter. The water quality index (WQI) was mostly influenced by coliform bacterial count and pH with highest mean effective weights of 39.15% and 26.65% respectively. Evaluation of the water suitability for drinking purpose reveals that the Jhelum River Basin has mostly retained excellent water quality (66% of data points) but poses safety concerns in downstream segments due to anthropogenic signatures. [ABSTRACT FROM AUTHOR]