Author: King-tung Chan
Publisher:
ISBN:
Category : Freshwater invertebrates
Languages : en
Pages : 354

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Author: King-Tung Chan
Publisher:
ISBN: 9781361412367
Category :
Languages : en
Pages :

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Book Description

Author: D Gallacher
Publisher: Open Dissertation Press
ISBN: 9781374780231
Category :
Languages : en
Pages :

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Book Description
This dissertation, "The Use of Benthic Macroinvertebrate Communities as Biomonitors in Hong Kong Streams" by D, Gallacher, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. DOI: 10.5353/th_b3124169 Subjects: Benthic animals - China - Hong Kong Water quality biological assessment - China - Hong Kong

Author: 梁士倫
Publisher:
ISBN: 9781374784635
Category :
Languages : en
Pages :

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Author: Sze-lun Leung
Publisher:
ISBN:
Category : Freshwater invertebrates
Languages : en
Pages : 530

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Book Description

Author: Raj Kiran Parmar
Publisher:
ISBN:
Category : Aquatic invertebrates
Languages : en
Pages : 124

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Book Description
Land cover change strongly affects biodiversity in stream ecosystems, with several studies demonstrating the negative impacts of agricultural and urban expansion on local community richness. However, little is known of the effects of land cover on the variation among sets of local communities in stream networks, as well as the drivers of community variation in these systems. Using the metacommunity framework, this study takes a multi-scale approach to understand how macroinvertebrate communities are assembled across three catchment land cover types; native forest, agricultural and urban. Specifically, the aims of this study are to assess; (1) how stream network land cover influences alpha and beta diversity of macroinvertebrate communities and, (2) the relative role of local environmental conditions and spatial dispersal variables in structuring these communities. Benthic macroinvertebrate samples and local in-stream and riparian environmental variables were collected at 20 sampling sites in each of the six study stream networks in Auckland. Spatial distance proxies of macroinvertebrate dispersal in stream networks were calculated using geospatial techniques. Community alpha and beta diversity, environmental and distance variables were analysed using multivariate statistical techniques. Comparisons showed reference forest and impacted (agricultural and urban) networks supported distinct communities, with lower alpha diversity in the impacted stream networks. Unexpectedly, beta diversity in the impacted networks was greater than, or equal to the reference stream networks, with community dissimilarity almost entirely driven by species turnover. Overall, irrespective of land cover, macroinvertebrate communities were largely structured by local environmental conditions. Benthic substrate and the presence and composition of riparian vegetation were the most significant local environmental variables influencing community composition. Spatial dispersal limitation variables had a small, but significant, effect on inter-site community dissimilarity and overall community structure in each catchment. Network distance between local communities explained the greatest variation in community dissimilarity of the three distance types. This study identified potential drivers of macroinvertebrate community variation in Auckland streams, specifically highlighting the relative role of local environmental and spatial dispersal processes. The results of this study have relevance for biomonitoring and state of environment reporting of Auckland’s freshwater systems, as well as future stream rehabilitation projects.

Author: Leonard Sandin
Publisher:
ISBN:
Category : Benthos
Languages : en
Pages : 180

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Book Description

Author: Alysia Helena Perry
Publisher:
ISBN:
Category :
Languages : en
Pages : 74

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Book Description

Author: Shelly Pickett
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
The monitoring of changes in benthic macroinvertebrate communities over time facilitates the evaluation of changes in the function and structure of aquatic ecosystems. I hypothesize that it will be possible to reconstruct historic macroinvertebrate communities by examining gut contents of fishes preserved in natural history museums. Researchers can use this knowledge to estimate the historic benthic macroinvertebrate community for streams from which we have fish museum specimens. These historic data can then be compared to current data to see how macroinvertebrate communities have changed over time.In this study, the fishes whose gut content most accurately reflected the benthic macroinvertebrate community of a freshwater stream, specifically Marshalls Creek, were identified. Both fish species and benthic macroinvertebrates were collected at various sites of Marshalls Creek in East Stroudsburg, PA, in March, August, and December 2010. Collections were taken at different times of year to reflect seasonal variation both in species sampled and quantity collected. 231 fish were dissected and their gut contents identified. Bluespotted Sunfish, Redbreast Sunfish, and White Suckers were the species that best represented the benthic macroinvertebrate community from their gut content. These species can be used to predict 81% of the total summer taxa.If there are 10 museum specimens of the selected species available, (in this case 10 White Suckers, 10 Bluespotted Sunfish, and 10 Redbreast Sunfish), one could dissect a total of 30 fish and expect to identify 68% of the total taxa (both kicknet and gut taxa combined) found in the freshwater stream where the specimens originated.In order to estimate sampling distribution, using R 3.0.2, 100 simulations were run of each combination of three fish species to determine the average quantity of taxa consumed (to the family level) along with sampling variation. The benthic macroinvertebrate data obtained fromivthe dissection of museum specimens could then be compared to data obtained from more recently collected specimens (10 White Suckers, 10 Bluespotted Sunfish, and 10 Redbreast Sunfish) and a comparison made to determine how the macroinvertebrate community has changed over time. Are families associated with high quality streams missing from the current collection? Based on which macroinvertebrate families are present and/or absent, the types of stresses that have caused these absences can be determined.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
Macroinvertebrates in urban streams in Ohio are potentially compromised by habitat loss, by the annual peak discharge event, and by degraded water quality. The Mill Creek in Southwest Ohio is a significantly channelized river that collects storm water runoff, wastewater treatment plant effluent, permitted dischargers, sanitary sewers, and combined sewers. Channelization areas have had 12-40 years to re-grow. Most of the riparian zone, although narrow, is lined with trees that shade the channel. The result is eutrophication by nutrient loading, some toxic chemical spills, and habitat simplification. This study was designed to show the relative impacts of habitat and water quality on the macroinvertebrate community in a multi-stressed urban stream. Possible limiting factors were quantified and evaluated along the main-stem of the Mill Creek and related to the macroinvertebrates five times over the summer of 2000. The habitat was characterized using the Ohio EPA's QHEI, the estimated peak flow, and pebble counts. Water quality was quantified by the nutrient concentrations found. Both habitat and water parameters were compared to macroinvertebrate density, taxa richness, and the calculated metric, invertebrate community index. Data was collected for base flow in the summer and autumn of 2000-2001. The QHEI and the ICI were linearly related over transects done in four non-consecutive years within a decade. Multiple regression showed several habitat variables correlated to taxa richness. ANOVA identified average species richness was significantly impacted by both water quality and habitat variables. A non-parametric method (detrended canonical correspondence analysis) separated the determinants for invertebrate communities along a nutrient (19.1% of variance) and habitat axis (11.1% of variance).