نتایج جستجو برای: biotic index

تعداد نتایج: 408379  

2017
L. HARIG

The purpose of this study was to compare the present biotic integrity of a central Ohio headwater stream with the conditions in 1940. Major changes in fish faunal composition occurred in Delaware Run over this time period. Only 33% (11 of 33) of the totalspecies collected were present in both years. Indices of biotic integrity (IBI) estimated for the 1940 data indicated that the stream was in g...

2003
LEWIS L. OSBORNE STEVEN L. KOHLER PETER B. BAYLEY WILLIAM A. BERTRAND MICHAEL J. WILEY RANDY SAUER

—The index of biotic integrity (IBI) has become a widely used tool for assessing the condition of stream fish communities and the overall biological status of streams. Because the location of a stream in a drainage network can influence the species richness offish communities and because species richness is an important component of the IBI, we examined the influence of stream spatial location ...

Journal: :Brazilian journal of biology = Revista brasleira de biologia 2010
P F Costa U H Schulz

The basin of the Sinos River, located in the northeastern part of Rio Grande do Sul state, Brazil, has been highly impacted by industrial and urban activities. Water quality is low because of domestic and industrial sewage discharges. Most of the tributaries have suffered drastic structural interventions like canalisations and the removal of riparian vegetation. The aims of this study were to: ...

2004
Grace Chiu Peter Guttorp

The NRCSE was established in 1996 at the University of Washington. Center activities include workshops and other research activities in areas of statistical methodology related to scientific problems in the environmental and ecological sciences. SUMMARY Stream health is often measured by the multimetric benthic index of biotic integrity (B-IBI). For Puget Sound Lowland (PSL) streams, the B-IBI ...

2012
Yung-Chul Jun Doo-Hee Won Soo-Hyung Lee Dong-Soo Kong Soon-Jin Hwang

At a time when anthropogenic activities are increasingly disturbing the overall ecological integrity of freshwater ecosystems, monitoring of biological communities is central to assessing the health and function of streams. This study aimed to use a large nation-wide database to develop a multimetric index (the Korean Benthic macroinvertebrate Index of Biological Integrity—KB-IBI) applica...

2000
Jimmie Pigg Mark S. Coleman Jay Wright

Between 1976 and 1996 the fish of the Deep Fork River were sampled at three sites. A total of 163,358 specimens from 36 species was taken. To determine if changes had occurred since 1976 as a result of modifications in the aquatic environment, the fish communities at each of the three sampling stations were compared. Three periods during which well defined environmental changes that resulted in...

2006
I. Czerniawska-Kusza

The objective of this investigation was to evaluate the usefulness of the artificial substrate sampler in collecting macroinvertebrates for water quality assessment of Polish lowland rivers. This paper presents the results of a comparative study between two different sampling techniques, i.e. nettings filled with brick as artificial substrates and handnet sampling. The validity of applying the ...

Journal: :Brazilian journal of biology = Revista brasleira de biologia 2010
L Bieger A B P Carvalho M N Strieder L Maltchik C Stenert

Macroinvertebrate communities are one of the most used groups in assessments of water quality, since they respond directly to the level of contamination of aquatic ecosystems. The main objective of this study was the assessment of the water quality of the Sinos River basin (Rio Grande do Sul state, Brazil) through biotic indices based on the macroinvertebrate community ("Family Biotic Index - F...

2008
Andrew C. Rehn Jason T. May Peter R. Ode

Executive Summary Bioassessment is the science of using aquatic organisms as indicators of ecological condition in streams in rivers. Many types of organisms can be used as indicators, for example fish or algae, but bioassessment is most frequently based on benthic macroinvertebrates (BMIs), which are small but visible bottom-dwelling organisms such as insects. BMI data sets typically consist o...

2006
Edward L. BOONE Eric P. SMITH

Understanding the relationship between an index of biological community state and habitat is important for policy makers and environmental managers. A common approach to modeling this relationship is to use regression. However, this simple method becomes complicated when the data are clustered and have both within-cluster and between-cluster spatial correlation. This article proposes a Bayesian...

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