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DigitalCommons@USU
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The approaches that researchers use to generate knowledge typically vary with the state of knowledge within a discipline: description of phenomena during early phases, documentation of patterns and explanatory proposals during intermediate stages,...
2008-01-01
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We developed empirical models for fish, macroinvertebrate, and diatom assemblages to assess the biological condition of 268 streams sampled from 1993 to 2002 in 7 major river basins in the Appalachian region of the USA. These models estimate the...
2008-01-01
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. Diatom-based indicators can contribute significantly to comprehensive assessments of stream biological conditions. We used modeling to develop, evaluate, and compare 2 types of diatom-based indicators for Idaho streams: an observed/expected...
2007-01-01
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The contribution of rare taxa to bioassessments based on multispecies assemblages is the subject of continued debate. As a result, users of predictive models such as River InVertebrate Prediction and Classification System (RIVPACS) disagree on...
2007-01-01
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Recent comparisons of benthic macroinvertebrate (BMI) sampling protocols have shown that samples collected from different habitat types generally produce consistent stream classifications and assessments. However, these comparisons usually have...
2007-01-01
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1. The predictive modelling approach to bioassessment estimates the macroinvertebrate assemblage expected at a stream site if it were in a minimally disturbed reference condition. The difference between expected and observed assemblages then...
2006-01-01
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1 Biological indicators are used to measure the biological health of ecosystems. Resource managers may uncritically assume that such indicators give unbiased estimates of true biological condition, but this assumption is largely untested. Use of...
2005-01-01
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The ratio of the number of taxa observed at a site to that expected to occur in the absence of anthropogenic impacts (O/E) is an ecologically meaningful measure of the degree of faunal alteration. We used O/E ratios to describe the response by...
2005-01-01
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Predictive models such as River InVertebrate Prediction And Classification System (RIVPACS) and AUStralian RIVer Assessment System (AUSRIVAS) model the natural variation across geographic regions in the occurrences of macroinvertebrate taxa in...
2005-01-01
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1. Numerous methods have been developed to sample the biota occurring in different ecosystems. However, the comparability of data derived from different sampling methods is generally unknown and is a major concern when integrating data from...
2005-01-01
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We evaluated the influence of various sources of sampling error on the precision, accuracy, and sensitivity of bioassessments based on River Invertebrate Prediction and Classification System (RIVPACS)-type models. We used data from 98 minimally...
2004-01-01
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Comprehensive global studies of stream invertebrate assemblages are rare and have produced contradictory results. To address this shortcoming, we compiled data from 495 published estimates of local genera richness for three orders of...
2003-01-01
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1. Biological assemblage surveys primarily aim to characterise species composition and relative abundance at one or more spatial or temporal scales. Data interpretation and conclusions are dependent on how well samples characterise the assemblage...
2003-01-01
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Bioassessment is the process of determining if human activity has altered the biological properties of an ecosystem. To quantify assessments we must be able to specify those biological properties that are either expected to occur in the absence of...
2000-01-01
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This paper summarizes and synthesizes the collective results that emerged from the series of papers published in this issue of J-NABS, and places these results in the context of previously published literature describing variation in aquatic biota...
2000-01-01
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We examined the ability of 5 a priori landscape classifications (3 sizes of catchments, ecoregions, and life zones) to partition observed variation in the composition of stream invertebrate assemblages. Analyses were based on 254 unimpaired sites...
2000-01-01
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We tested 4 current hypotheses about how trout predation and habitat structure affect lentic invertebrate assemblages. The hypotheses were 1) trout predation affects larger-bodied species and individuals more strongly than small ones, 2) brook and...
1998-01-01
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We examined subadult humpback chub densities along 24 kms of the Colorado River in the Grand Canyon to: (1) identify geomorphic conditions in the study area; (2) determine associations between subadult humpback chub (TL) habitat use and geomorphic...
1998-01-01
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We review the major conceptual developments that have occurred over the last 50 years concerning the factors that influence insect biodiversity in streams and examine how well empirical descriptions and theory match. Stream insects appear to...
1998-01-01
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Temperature is known to be an important mechanism affecting the growth and distribution of stream insects. However, little information exists that describes how variable temperatures are among streams of similar size, especially in physically...
1997-01-01
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This historical and conceptual overview of riparian ecosystem restoration discusses how riparian ecosystems have been defined, describes the hydrologic, geomorphic, and biotic processes that create and maintain riparian ecosystems of the western...
1997-01-01
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In this study, we examined the site-specific effects of a large episodic flood on the riparian vegetation within the floodplain of the San Luis Rey River in southern California. Using multispectral airborne videography, we quantified percent cover...
1997-01-01
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Successful long-term wetland restoration efforts require consideration of hydrology and surrounding land use during the site selection process. This article describes an approach to initial site selection in the San Luis Rey River watershed in...
1997-01-01
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We present a conceptual model for identifying restoration sites for riparian wetlands and discuss its application to reaches within the Upper Arkansas River basin in Colorado. The model utilizes a Geographic Information System (GIS) to analyze a...
1997-01-01
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