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Macroinvertebrate Community Structure Of Headwater Streams Of The Buffalo National River Arkansas In Relation To Physicochemical Environmental Variables
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Book Synopsis Macroinvertebrate Community Structure of Headwater Streams of the Buffalo National River, Arkansas, in Relation to Physicochemical Environmental Variables by : Carl Willard Dick
Download or read book Macroinvertebrate Community Structure of Headwater Streams of the Buffalo National River, Arkansas, in Relation to Physicochemical Environmental Variables written by Carl Willard Dick and published by . This book was released on 1998 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Macroinvertebrate Community Composition in Stream Networks Across Three Land Cover Types by : Raj Kiran Parmar
Download or read book Macroinvertebrate Community Composition in Stream Networks Across Three Land Cover Types written by Raj Kiran Parmar and published by . This book was released on 2018 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Book Synopsis The Influence of Network Structure, Habitat Fragmentation, and Faunal Sources on Aquatic Communities in Headwater Streams by : Sean D. Sipple
Download or read book The Influence of Network Structure, Habitat Fragmentation, and Faunal Sources on Aquatic Communities in Headwater Streams written by Sean D. Sipple and published by . This book was released on 2017 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Headwater streams comprise the majority of the stream network, providing important ecological functions to the downstream network. Although we are beginning to understand how network structure may influence fish, our understanding of how it influences benthic macroinvertebrate dispersal and population connectivity is limited. We also know little about how these patterns and processes may be disrupted as a result of human-driven landscape change such as stream barriers to movement and creation of artificial habitats such as stormwater and farm ponds. In this study, I investigated the effect of stream network position, stream size, and local habitat on benthic macroinvertebrates, and determined to what degree road crossings and impoundments may be degrading benthic macroinvertebrate and fish communities in headwater streams. These mechanisms were explored using Maryland Department of Natural Resources, (MDNR) Maryland Biological Stream Survey (MBSS) benthic macroinvertebrate, fish, and environmental data from first-order streams in the Piedmont region of Maryland. Using an Information Theoretic Approach (ITA), models were developed based on the hypothesized relationships between benthic macroinvertebrate and fish community structure and several network and anthropogenic impact variables. Based on my results, aquatic community structure was dependent on local habitat conditions and stream network structure. Both assemblages responded negatively to roads, which may suggest an isolation effect. These results also suggest that impoundments are acting as sources for benthic macroinvertebrates and fish, including non-native species.
Book Synopsis Relationships Between Aquatic Macroinvertebrate Community Structure and Selected Environmental Variables by : Ashley Christine Lenig
Download or read book Relationships Between Aquatic Macroinvertebrate Community Structure and Selected Environmental Variables written by Ashley Christine Lenig and published by . This book was released on 2004 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Macroinvertebrate Community Structure and Feeding Dynamics in Three Forested Headwater Streams in Central Maine by : Emily R. Arsenault
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.
Book Synopsis Macroinvertebrate Community Assessment of the Mid-reaches of the Buffalo National River by : Faron D. Usrey
Download or read book Macroinvertebrate Community Assessment of the Mid-reaches of the Buffalo National River written by Faron D. Usrey and published by . This book was released on 2001 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Patterns and Determinants of Macroinvertebrate Diversity in Headwater Stream Networks by : Amber Clarke
Download or read book Patterns and Determinants of Macroinvertebrate Diversity in Headwater Stream Networks written by Amber Clarke and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Headwater streams dominate stream channel length in catchments. They are important sources of water, sediment and biota for downstream reaches and critical sites for organic matter and nutrient processing. Aquatic biodiversity in headwater streams has been overlooked in comparison to higher-order rivers, and few studies have considered spatial biodiversity patterns in headwater streams, or streams in general. I reviewed studies of macroinvertebrate diversity in headwater streams and found equivocal evidence to support the view that headwater streams harbour high biodiversity. Headwater streams might still make an important contribution to [gamma] (regional) diversity at the landscape (catchment) scale by virtue of high [beta] (among-assemblage) diversity. I studied eight headwater streams from three forested, upland catchments along the Great Dividing Range, Victoria, Australia to test my hypothesis of high [beta] diversity and to understand the spatial patterns and determinants of macroinvertebrate diversity in headwater stream networks.Diversity partitioning showed that reaches each had high [alpha] (within-assemblage) diversity, while [beta] diversity made only a small contribution to [gamma] diversity at both the reach and catchment scales. [beta] diversity may have been lower than hypothesized due to relatively small distances between sites and high levels of dispersal among reaches and catchments in the study area. Contrary to other studies that have found environmental factors to be important for explaining variation in macroinvertebrate assemblage structure in headwater streams, I found a limited role for environmental factors structuring macroinvertebrate assemblages in the study area.In one year (2008), spatial factors (independent of environmental factors) were the dominant factor structuring macroinvertebrate assemblages. Therefore, metacommunity structure in the study area aligns most closely with the neutral/patch dynamic metacommunity model. This pattern of spatial structuring, coupled with low [beta] diversity, suggests that high neighbourhood dispersal might be the main factor structuring macroinvertebrate assemblages in the study area. Flow permanence had only a seasonal effect on macroinvertebrate diversity and so there is a temporal component to the spatial diversity patterns in this system.The explicit recognition of stream ecosystems as spatially structured networks has increased our understanding of ecological patterns and processes, and provided the impetus for this research. Recent advances in the study of networks, particularly in the fields of physics and network theory, offer an opportunity to considerably extend the current application of the network concept in stream ecology.Determining the relative contributions of [alpha] and [beta] diversity to [gamma] diversity, and the scale dependence of [alpha] and [beta] components, provides vital information for conservation planning because optimal reserve designs will differ depending on the relative contributions of [alpha] and [beta] diversity. My finding of high [alpha] and low [beta] diversity indicates that each stream in the study area can be considered to have low irreplaceability and the capacity to contribute a large portion of species to regional conservation targets.Information on spatial patterns of diversity is urgently required for systematic conservation planning for freshwater reserves if we are to halt the rapid decline in global freshwater biodiversity.
Book Synopsis Assessing Organic Matter Breakdown and Associated Macroinvertebrate Community Structure in Headwater Streams by : Miller Scott Jarrell
Download or read book Assessing Organic Matter Breakdown and Associated Macroinvertebrate Community Structure in Headwater Streams written by Miller Scott Jarrell and published by . This book was released on 2009 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis An Assessment of the Macroinvertebrate Community of the Buffalo National River by : Charles Thomas Bryant
Download or read book An Assessment of the Macroinvertebrate Community of the Buffalo National River written by Charles Thomas Bryant and published by . This book was released on 1997 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The Relationships Between Headwater Stream Macroinvertebrate Communities and Summer Low-flow Events in a Temperate Rain Forest by :
Download or read book The Relationships Between Headwater Stream Macroinvertebrate Communities and Summer Low-flow Events in a Temperate Rain Forest written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Using a forested headwater stream system as a model, the effects of inter-annual variation in summer discharge regimes on aquatic insect communities were investigated. More specifically, the benthic invertebrate community response to the intensity, minimum discharges, frequency, duration and abruptness of summer low-flow events were examined. We hypothesized that intensification of summer low-flow events, both in duration and magnitude, have some negative impacts on benthic macroinvertebrate communities in riffles. Examples of negative impacts include reduction in their abundance and/or biodiversity. First, the abundance and functional trait data of the benthic macroinvertebrates in the three streams in the Malcolm Knapp Research Forest, British Columbia, Canada, were analyzed with respect to the low-flow events. Second, population models were built to simulate the potential responses of lotic aquatic insect communities to future climate change scenarios that differ in the rate of intensifications in extreme flow events: a low-flow event scenario within the current range versus 10% increase in intensity. The summer low-flow events were found to have a significant relationship with benthic macroinvertebrate communities through three-table ordinations of the empirical data. The community structure was correlated with a major ocean-atmosphere regime shift (Pacific Decadal Oscillation). The intensity and duration of low-flow events explained the observed shift in community structure favouring r-selected traits (e.g. short life cycle, high reproduction rate). The two low-flow severity scenarios showed the significant differential impacts on the aquatic insect community structures when individual populations were modeled according to their traits. Aquatic insects could be separated into three groups according to their sensitivities, measured by extinction rates, toward the two scenarios.
Book Synopsis Determining the Association Between the Structure of Stream Benthic Macroinvertebrate Communities and Agricultural Best Management Practices by : Roger Holmes (M.Sc.)
Download or read book Determining the Association Between the Structure of Stream Benthic Macroinvertebrate Communities and Agricultural Best Management Practices written by Roger Holmes (M.Sc.) and published by . This book was released on 2014 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: Farmers have been encouraged to adopt more sustainable farming practices (BMPs) that mitigate adverse agricultural effects on the natural environment. However, the ability of BMPs to protect or restore riverine systems continues to be questioned due to limited evidence directly linking BMP use with improved ecological conditions. The exclusion of hydrological pathways in previous field studies may explain why a direct link has not yet been established. The goal of this study was to assess the association between benthic macroinvertebrate community structure and the number and location of agricultural BMPs. Macroinvertebrates and water chemistry were sampled in 30 headwater catchments in the Grand River Watershed. Catchments exhibited gradients of BMP use and location as measured by the degree of hydrologic connectedness. Stepwise ordination regressions and variance partitioning were used to determine which environmental variables (i.e., BMP metrics, water chemistry parameters, habitat characteristics, and land use variables) were associated with benthic macroinvertebrate community structure. Water chemistry parameters were negatively associated with BMP metrics suggesting BMPs were mitigating losses of nutrients and sediments. However, BMP abundance and location explained minimal variation in benthic macroinvertebrate structure within the 30 sampled catchments. The absence of a strong association between BMPs and benthic macroinvertebrates may indicate a need for greater numbers and targeted siting of BMPS to improve water quality beyond a threshold point that would allow recolonization of intolerant invertebrate taxa. Focusing of conservation goals on ecological conditions and the promotion of BMPs that enhance in-stream habitat may also be required.
Book Synopsis Macroinvertebrate Community Structure and Function in Seasonal, Low-land, Tropical Streams Across a Pristine-rural-Urban Land-use Gradient by : Julie Elizabeth Helson
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:
Book Synopsis Using the Reference Condition Approach to Assess the Effects of Environmental Stressors on the Benthic Macroinvertebrate Community Structure of Precambrian Shield Headwater Streams by : Beth Gilbert
Download or read book Using the Reference Condition Approach to Assess the Effects of Environmental Stressors on the Benthic Macroinvertebrate Community Structure of Precambrian Shield Headwater Streams written by Beth Gilbert and published by . This book was released on 2006 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Factors Influencing Macroinvertebrate Assemblage Structure in an Agricultural Headwater Stream System of the Midwestern United States by : Hector R. Santiago
Download or read book Factors Influencing Macroinvertebrate Assemblage Structure in an Agricultural Headwater Stream System of the Midwestern United States written by Hector R. Santiago and published by . This book was released on 2007 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Although the notion that streams are influenced by the character of their landscape at multiple spatial scales is not new, the relative degree to which local versus regional factors affect ecological function in streams is not fully understood, and can be different between geographically proximate watersheds. Anthropogenic disturbances to the landscape such as agricultural practices can be detrimental to stream ecosystems. This study examined the influences of local habitat and riparian corridor condition compared to regional landscape influences on benthic macroinvertebrate assemblages in a Midwestern agroecosytem. Twenty-four reaches in the North Fork and Upper Fork sub-basins of the Sugar Creek watershed, Wayne County, Ohio were sampled to better understand how different habitat and landscape factors affect the structure of macroinvertebrate assemblages in these impacted headwater streams. A total of 72,529 macroinvertebrates representing 79 families in 22 orders were collected during Autumn of 2005 and Spring 2006 to compare assemblage structure between watersheds and across seasons. Family richness, evenness, and diversity showed no difference attributable to watershed, while evenness and diversity exhibited seasonal differences. Chironomid abundance seemed to account for the seasonal change. Percent Ephemeroptera, Plecoptera, and Trichoptera (%EPT) was significantly influenced by watershed and season with the North Fork watershed exhibiting a higher abundance of these pollution tolerant and habitat sensitive taxa than the Upper Fork at all sample sites. A Geographic information system (GIS) was used to delineate sample watersheds and analyze landscape character. Proportion (%) of low Intensity residential, high intensity residential, industrial/commercial, deciduous forest, evergreen forest, mixed forest, row crop, pasture/hay, wooded wetland and herbaceous wetland were calculated per hydrologic unit. The dominant land uses in both study watersheds were crop, pasture, deciduous forest, and low intensity residential. The North Fork exhibited a significantly higher proportion of pasture and deciduous forest land types than the Upper Fork, which was dominated by row crops, then pasture and forest respectively. North Fork had almost twice the amount of deciduous forest as did the Upper Fork. Canonical correspondence analysis (CCA) was used to assess the macroinvertebrate family-environment relationship and variance partitioning determined the degree of influence of 8 local and 8 regional environmental factors on invertebrate assemblage structure in each study basin. Local habitat factors explained 25.8% of the total variance while regional landscape factors explained 23.6% of the total variance with 2.7% of the variability shared by both. Upper Fork sites were generally scattered along a silt/muck to cobble habitat gradient, while North Fork sites were arranged along a pasture-forest to rowcrop landscape gradient. The higher proportion of pasture and deciduous forest in the North Fork may explain the greater distribution of EPT taxa found in the watershed, while the greater proportion of crops and smaller proportion of forest in the Upper Fork may explain the greater influence of fine substrates in the watershed. Other environmental factors including glacial geology and groundwater influence may have also contributed to these differences by introducing coarser substrates and cooler, stream temperatures.
Book Synopsis Spatial Structuring of Benthic Invertebrate Communities Within and Among Wooded Headwater Stream Networks by : Sara Elizabeth Wright
Download or read book Spatial Structuring of Benthic Invertebrate Communities Within and Among Wooded Headwater Stream Networks written by Sara Elizabeth Wright and published by . This book was released on 2011 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biotic communities in low order streams are influenced by multiple factors that may reflect both environmental conditions within individual watersheds, and also bio-geographic considerations such as spatial proximity of streams and organism dispersal/recruitment abilities. Prior work in small streams of Western New York (Allegheny Plateau) revealed little or no spatial structuring of biota among separate steams, but instead convincing effects of stream and watershed environmental factors. In this study, we further explored the roles of spatial vs. environmental influences by now comparing 1st - 3rd-order streams longitudinally within a stream network in addition to comparing physically separated streams. Within-stream drift adds a new dispersal dimension that is not present between streams. Four stream networks, each with a consecutive series of a 1st, a 2nd, and a 3rd order segment, were selected in a contiguously wooded sector (2nd growth through moderately disturbed old growth northern hardwoods) of Allegheny State Park near the Pennsylvania border. Three replicate Surber samples and a qualitative sample were collected from each stream site in fall 2010 and spring 2011. Similarity/dissimilarity among streams was explored by Euclidean distance matrices for community composition, stream/watershed environmental characteristics (in-stream habitat, watershed land cover, etc.), and spatial distance. Non-metric multidimensional scaling ordination of community composition and Principal Components Analysis ordination of environmental variables of the twelve stream segments were employed. Community composition of in-stream biota was based on the identification of 117 taxa representing fifty-three families. Spearman rank correlation indicated ten out of twelve of most abundant taxa were associated with the larger streams, trending away from the first orders. A One-Factor ANOVA of site-to-site biotic distances revealed no significant differences among longitudinal within stream pairings, like order pairings, and all possible remaining pairs. The streams in this study were quite readily grouped by ordination of the environmental variables, but this did not generally translate to biotic structuring. A significant partial correlation was, however, found between distances based on environmental "channel only" variables (i.e. not including watershed geography) and based on the biota within stream orders, when controlling for spatial distances. There was no evidence of spatial structuring of benthic communities. The macroinvertebrate community composition appeared to comply somewhat with the niche-based sorting theory and decidedly not with neutral theory/spatial autocorrelation. Continuing to decipher the dynamics of macroinvertebrate community composition can prove valuable to conservation and restoration approaches.
Book Synopsis Fish Communities and Their Relation to Physical and Chemical Characteristics of Streams from Selected Environmental Settings in the Lower Susquehanna River Basin, 1993-95 by : Michael D. Bilger
Download or read book Fish Communities and Their Relation to Physical and Chemical Characteristics of Streams from Selected Environmental Settings in the Lower Susquehanna River Basin, 1993-95 written by Michael D. Bilger and published by . This book was released on 1998 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis A Two-year Seasonal Comparison of the Macroinvertebrate Community Structure of Four Ozark Streams Experiencing Differing Degrees of Anthropogenic Disturbance by : Christina Diane Bradley
Download or read book A Two-year Seasonal Comparison of the Macroinvertebrate Community Structure of Four Ozark Streams Experiencing Differing Degrees of Anthropogenic Disturbance written by Christina Diane Bradley and published by . This book was released on 2001 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt:
