Download or read book Seasonal and Longitudinal Changes in Functional Feeding Group Composition of Benthic Macroinvertebrates in the San Marcos River Texas written by Joseph McMurry Owen and published by . This book was released on 1996 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Seasonal and Longitudinal Investigation on the Impacts of Recreational Activities on the Aquatic Macroinvertebrate Community Within the San Marcos River written by Ovie Oluwanisola Agare and published by . This book was released on 2016 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the San Marcos River, recreational activities are most pronounced between April and October. Given the continued urbanization and increasing population in San Marcos there is need for a quantitative study on the possible effect of elevated recreational activities on the aquatic macroinvertebrates within the river. Furthermore, currently, there has been no study which quantified patterns in macroinvertebrate drift and benthic community structure simultaneously in the San Marcos River. Information on drift patterns and benthic macroinvertebrate habitat relationships is necessary to understand mechanisms for species persistence within the San Marcos River. In this study, I examined the seasonal and longitudinal patterns of benthic macroinvertebrate community composition at three different sites within the San Marcos River. I also examined the seasonal and longitudinal response of the drifting aquatic macroinvertebrates to changes in their habitat as a result of recreational activities in the San Marcos River. Tubing and swimming accounted for most of the recreation activity (>90%). Across all seasons, the upstream most study site had the highest drift densities compared to two downstream study sites. Canonical Correspondence Analysis (CCA) results explained 15.3% of the variability in the San Marcos River benthic macroinvertebrate community among vegetated habitats and 23.9% among open substrate habitats. Study results indicated that drift is related to benthic abundance. Macroinvertebrate drift densities followed the typical circadian pattern observed in other river systems and results indicated no increase in macroinvertebrate drift density during the peak recreation period. Conclusively, study results indicated that macroinvertebrates at the two upstream sites were not impacted by recreation and turbidity. However, the lower most study site, based on the CCA results indicate that substrate and turbidity are factors influencing the macroinvertebrate community.
Download or read book Longitudinal and Seasonal Variation in Macroinvertebrate Taxonomic and Functional Feeding Group Composition of a Central Texas Stream written by Darrel C. Solanik and published by . This book was released on 1996 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Longitudinal Changes in Stream Benthic Macroinvertebrate Community Trophic Structure Along Two Central Texas Headwater River Continua written by Brian Richard Creutzburg and published by . This book was released on 2000 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Taxonomic Diversity Assemblage Structure and Biotic Integrety of Benthic Macroinvertebrates in the Guadalupe San Marcos River System written by C. Lexi Smith and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Freshwater ecosystems are historically known to support a wide range of biodiversity at various trophic levels. However, the loss of freshwater biodiversity is related to trends in deteriorating water quality caused by anthropogenic disturbances that negatively impact bioindicator communities (e.g., benthic macroinvertebrates; BMI). I incorporated parameters of the Texas Commission of Environmental Quality (TCEQ) Rapid Bioassessment Protocols (RBP) to assess taxonomic diversity, assemblage structure, and biotic integrity of BMI in the Guadalupe – San Marcos River System (GSMR) in Texas. I sampled 25,512 BMI from 44 sites of the GSMR within various sampling methods, regions, habitats, and substrates. Taxonomic diversity and assemblage structure of BMI appeared to be homogenous across the river system regardless of sampling method, habitat, and substrate. However, regions suggested the San Marcos River of having the highest alpha diversity, lowest beta diversity, and greatest biotic integrity compared to the observed anthropogenic disturbance of the Guadalupe River overall. My study emphasizes the need for improved efforts towards large river management and conservation efforts of biotic communities by identifying the structural relationship of BMI assemblages in the GSMR. My results will help improve bioassessments and continuing research for BMI assemblages found within a large river system.
Download or read book Benthic Macroinvertebrate Community Structure in Relation to Water Quality and Habitat in the Upper Pecos River Texas written by Greg L. Larson and published by . This book was released on 1996 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rapid Bioassessment Protocols for Use in Streams and Rivers written by and published by . This book was released on 1989 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Macroinvertebrate Functional Organization Diversity and Life History Variation Along a Sierra Nevada River Continuum California written by Richard Lee Bottorff and published by . This book was released on 1990 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Macroinvertebrate Community Structure and Function in Seasonal Low land Tropical Streams Across a Pristine rural Urban Land use Gradient written by Julie Elizabeth Helson and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Benthic Macroinvertebrate Community Composition and Distribution Related to Seasonal and Geochemical Changes in a Chronically Acidified Stream written by Darlene Marie Madarish and published by . This book was released on 1997 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spatial Variation in Macroinvertebrates in Groundwater dominated Rivers written by Kirby Lynn McCready Wright and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Benthic macroinvertebrate communities in riverine ecosystems are shaped by both local and large-scale influences. Most models of riverine community structure are grouped into either discrete or continuum conceptual models. However, there is much uncertainty in how these two classes of conceptual models apply to macroinvertebrate communities in the physicochemically consistent headwaters of spring-influenced rivers. This thesis examined benthic macroinvertebrate community composition and biomass among local discrete geomorphic mesohabitats (riffles, runs, and pools) and along an upstream to downstream gradient in two spring-fed rivers in central Texas (San Marcos River and Comal River, Hays County). The goal of my thesis was to examine the relative importance of downstream distance from springhead versus smaller-scale habitat conditions (i.e., mesohabitat units) in explaining the variation in macroinvertebrate community structure in these two spring-based subtropical riverine systems. I hypothesized that, because I sample in the upper physicochemically consistent reaches of both rivers that local mesohabitat conditions would explain more variation in community composition than downstream distance from springhead. I expected this change in community composition would be driven by replacement of taxa rather than differences in taxonomic richness. I also predicted that non-native benthic species would be more evenly distributed throughout the study reaches due to the consistency of physicochemical conditions. Finally, I predicted that the distribution of taxa specific biomass contributions will follow patterns seen in community composition change and will reflect taxonomic density estimates. To test these hypotheses, I sampled macroinvertebrates and local habitat parameters from mesohabitat types along three reaches in the first ~4 km of each river. I also determined biomass of each taxon and community-wide patterns of biomass distribution of benthic macroinvertebrates. I found that variation in taxonomic composition in both rivers was driven to a greater or equal amount by upstream to downstream distance from spring-influence, and by mesohabitat type. Taxonomic diversity did not vary with distance from springhead but was consistently lower in pool mesohabitats when compared to runs and riffles in both rivers. Compositional changes and patterns in b-diversity within mesohabitat types among study reaches indicated that replacement (as opposed to richness differences) was the main mechanism leading to patterns of b-diversity. I found that a non-native snail (Tarebia granifera) and an endemic spring snail (Elimia comalensis) appear to be spatially partitioning habitat in an upstream- to downstream manner. Finally, I found that Tarebia granifera constituted the largest proportion of benthic macroinvertebrate biomass in several study reaches downstream from springheads.
Download or read book Seasonality and Community Structure of Benthic Macroinvertebrates in the Lower Pascagoula River Mississippi written by Roger Adams Jennings and published by . This book was released on 1984 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Macroinvertebrate Community Structure and Feeding Dynamics in Three Forested Headwater Streams in Central Maine written by Emily R. Arsenault and published by . This book was released on 2014 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: Headwater streams have some of the best quality water in the country (Dissmeyer 2000). Because headwaters eventually flow into other downstream water bodies like rivers and lakes, they are important places to focus research and conservation efforts. All streams in this study had good water quality based on several assessments of macroinvertebrate communities. 1. Judging from metrics of abundance, richness, EPT, and HBI, all study streams had very good water quality. Thirty-nine total families were observed among the three streams. Whittier Stream was the least healthy of the three, most likely as a result of human disturbances such as a road crossing, fishpond, and mill remnants. It is probable these habitat alterations are having an effect on downstream benthic communities. 2. The riparian zone of each stream was forested and stable, but there were some eroding banks at some points along the study reaches. The abundance of sensitive macroinvertebrates (measured using representative Orders Ephemeroptera, Plecoptera, and Trichoptera) increased with increasing percent canopy cover and decreased with high percentages of sand characterizing the streambed. 3. Macroinvertebrates can be categorized into functional feeding groups based on feeding behavior. Shredders should hypothetically be in high abundance in headwater streams due to high riparian organic matter inputs. However, observed shredders were limited. This may be due to seasonal changes in functional feeding group ratios. In addition, all study streams had a predator/prey ratio that was higher than the ratio expected for a typical stream, which suggests that there might be an abundance of prey biomass in the study stream headwaters. 4. Based on results from stable isotope analysis of carbon and nitrogen, most macroinvertebrates within the study streams seem to be omnivorous. The most complex food web was observed at Stony Brook. Food webs of Beaver Brook and Stony Brook showed similar trophic clustering, a pattern that might be indicative of streams with excellent water quality.
Download or read book Biodiversity and Genetic Structure of Benthic Macroinvertebrates Along an Altitudinal Gradient written by Lauren Pulliam and published by . This book was released on 2016 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: Altitudinal gradients in Sub-Antarctic freshwater systems present unique opportunities to study the effect of distinct environmental gradients on benthic macroinvertebrate community composition and dispersal. This study investigates patterns in biodiversity, dispersal and population genetic structure of benthic macroinvertebrate fauna across an altitudinal gradient between two watersheds on Navarino Island in southern Chile. Patterns in diversity, density, evenness and functional feeding groups were not significantly different across the altitudinal gradient in both the Windhond and Róbalo Rivers. Taxa richness in both rivers generally increased from the headwaters of the river to the mouth, and functional feeding group patterns were consistent with the predictions of the River Continuum Concept. Population genetic structure and gene flow was investigated by sampling the mitochondrial cytochrome oxidase I gene in two invertebrate species with different dispersal strategies. Hyalella simplex (Amphipoda) is an obligate aquatic species, and Meridialaris chiloeense (Ephemeroptera) is an aquatic larvae and a terrestrial winged adult. Contrasting patterns of population genetic structure were observed. Results for Hyalella simplex indicate significant differentiation in genetic structure in the Amphipod populations between watersheds and lower genetic diversity in the Róbalo River samples, which may be a result of instream dispersal barriers. Meridialaris chiloeense exhibited weak population structure but higher genetic diversity, which suggests this species is able to disperse widely as a winged adult.
Download or read book Algal Ecology written by and published by Academic Press. This book was released on 1996-06-03 with total page 781 pages. Available in PDF, EPUB and Kindle. Book excerpt: Algae are an important component of aquatic benthic ecosystems because they reflect the health of their environment through their density, abundance, and diversity. This comprehensive and authoritative text is divided into three sections to offer complete coverage of the discussion in this field. The first section introduces the locations of benthic algae in different ecosystems, like streams, large rivers, lakes, and other aquatic habitats. The second section is devoted to the various factors, both biotic and abiotic, that affect benthic freshwater algae. The final section of the book focuses on the role played by algae in a variety of complex freshwater ecosystems. As concern over environmental health escalates, the keystone and pivotal role played by algae is becoming more apparent. This volume in the Aquatic Ecology Series represents an important compilation of the latest research on the crucial niche occupied by algae in aquatic ecosystems. Presents algae as the important player in relation to environmental health Prepared by leading authorities in the field Includes comprehensive treatment of the functions of benthic algae as well as the factors that affect these important aquatic organisms Acts as an important reference for anyone interested in understanding and managing freshwater ecosystems
Download or read book Ecology and Classification of North American Freshwater Invertebrates written by James H. Thorp and published by Academic Press. This book was released on 2010 with total page 1036 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The third edition of Ecology and Classification of North American Freshwater Invertebrates continues the tradition of in-depth coverage of the biology, ecology, phylogeny, and identification of freshwater invertebrates from the USA and Canada. This text serves as an authoritative single source for a broad coverage of the anatomy, physiology, ecology, and phylogeny of all major groups of invertebrates in inland waters of North America, north of Mexico." --Book Jacket.
Download or read book River Biota written by Peter P. Calow and published by Wiley-Blackwell. This book was released on 1996-08-06 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: As with all ecosystems, river systems involve a complex interaction of a rich diversity of micro-organisms, plants and animals with their physical and chemical environment. The river habitat presents unique problems for organisms exposed to unidirectional currents, seasonal variation in flow, and disturbance due to pollution and other human interference. The book starts with a description of the taxa, their adaptations and their ecologies, followed by chapters describing the ecosystem processes in terms of trophic interactions and the key production processes related to photosynthesis and decomposition. A major chapter then considers the principles, practices and problems associated with making reliable observations on river organisms, leading to final chapters investigating how river biota are impacted by human activity and how, in turn, they can be used as indicators of these effects in river-management programmes.
