Geology topics

Paul M. Stewart

Publications and source records attributed to Paul M. Stewart.

11 recordsLinked to original sources

USGS2009

Macroinvertebrate assemblages associated with patterns in land use and water quality

Most national parks were designated to preserve significant natural resources. Park borders often reflect political rather than ecological boundaries. Consequently, catchments of many streams are only partially within park boundaries, and are therefore subject to land use changes and potential contamination from non-point sources outside the park. The National Park Service has initiated a program to monitor natural resources, particularly those at risk from land use changes surrounding the parks. This effort requires the identification of response signatures indicative of the ecological effects of human activities. The goal of this chapter is to identify a biological response signature (e.g., indicator assemblages) for tributary streams in Cuyahoga Valley National Park. More than 20 first to fourth order tributary streams enter the Cuyahoga River within park boundaries. Many of these catchments are outside park boundaries and under suburban development. The purpose of this research is to provide park managers with a monitoring tool for identifying the extent and degree of aquatic resource degradation due to land use changes in tributary catchments.

Book chapter↗

USGS2009

Response signatures of four biological indicators to an iron and steel industrial landfill

Industrial landfills greatly modify surrounding areas by affecting chemical, physical, and biological integrity. Few data quantifying contaminant levels near landfills in sediments or in the organisms living near landfills exist. We examined several indicators of the aquatic community to determine whether a relationship existed between proximity to an industrial landfill and a decrease in biological integrity. The purpose was to determine patterns in community compositions and concentrations of contaminants in organisms and to assess the effects of contaminants on several trophic levels in the Grand Calumet Lagoons and adjacent ponds. In most aquatic systems, it is difficult to establish causal relationships between contaminants and ecosystem health due to the many ecological factors that can influence the responses of organisms and communities to particular stressors.

Book chapter↗

USGS2009

Effects of contaminated dredge spoils on wetland plant communities: A literature review

Contaminated dredge spoil is a national concern due to its scope and effects on biota, water quality, and the physical environment. This literature review discusses the effects of contaminated dredge spoils on wetland plant communities. Plant communities naturally shift over time with changing environmental conditions. Addition of toxins and nutrients and changes in hydrology may influence plant community structure. The storage and disposal of nutrient and metal contaminated dredge spoils may cause shifts in nearby plant communities. Shifts in species composition and diversity may not be observed for decades after nutrient enrichment, causing any disturbance to remain undetected. Plant community shifts often have great amounts of inertia and are difficult to reverse.

Book chapter↗

USGS2003

A Benthic Community Index for streams in the Northern Lakes and Forests Ecoregion

Encompassing the northern glaciated section of the Midwest United States, the Northern Lakes and Forests Ecoregion is characterized by mixed conifer and deciduous forests and wetlands. Sites were randomly selected in the ecoregion using the Environmental Protection Agency's Environmental Monitoring and Assessment Program designed to develop an index of biotic integrity for wadeable streams. Macroinvertebrates were sampled during the fall of 1998 and 1999 using a multi-habitat, composite-sample method. Two hundred forty-six invertebrate taxa in 97 families were collected from 94 sites. Ten of 42 candidate metrics satisfied metric selection criteria, including six structural metrics (number of Ephemeroptera taxa, number of Diptera taxa, richness, Shannon-Wiener diversity, percent Trichoptera abundance, and percent Crustacea and Mollusca abundance), two functional metrics (number of Filterer taxa and number of Scraper taxa), and two conditional metrics (number of Ephemeroptera, Trichoptera, and Plecoptera taxa and Hilsenhoff Biotic Index). These metrics were used to develop a Benthic Community Index to assess the biological integrity of wadeable streams in the ecoregion. Index values ranged from 10 to 50, and scores from impaired sites were significantly different than non-impaired sites (P<0.001). Index values were divided into three narrative interpretations of biological integrity (poor, fair, and good). After further testing, the index may provide a useful biological assessment tool for resource managers in the ecoregion.

Ecological Indicators↗

USGS2003

Effects of two classification strategies on a Benthic Community Index for streams in the Northern Lakes and Forests Ecoregion

Ninety-four sites were used to analyze the effects of two different classification strategies on the Benthic Community Index (BCI). The first, a priori classification, reflected the wetland status of the streams; the second, a posteriori classification, used a bio-environmental analysis to select classification variables. Both classifications were examined by measuring classification strength and testing differences in metric values with respect to group membership. The a priori (wetland) classification strength (83.3%) was greater than the a posteriori (bio-environmental) classification strength (76.8%). Both classifications found one metric that had significant differences between groups. The original index was modified to reflect the wetland classification by re-calibrating the scoring criteria for percent Crustacea and Mollusca. A proposed refinement to the original Benthic Community Index is suggested. This study shows the importance of using hypothesis-driven classifications, as well as exploratory statistical analysis, to evaluate alternative ways to reveal environmental variability in biological assessment tools.

Ecological Indicators↗

USGS2002

Development of a stream habitat index for the Northern Lakes and Forest Ecoregions

Physical habitat was quantified in 105 randomly selected streams across the Northern Lakes and Forests Ecoregion during 1998 and 1999 to develop a stream habitat index for the region. Physical habitat measures (106) were classified into four groups: substrate, instream cover, riparian zone–land use, and geomorphology–hydrology. Variable reduction procedures yielded seven variables: sinuosity, percent of substrate gravel or larger, percent substrate as detritus or muck, percent of bank with forested cover, amount of bank erosion, number of large logs per 100 m, and mean length of pools. Streams were separated by a gradient value of 3 m/km (low N = 70; high N = 35) and assigned to model and test data sets. For low-gradient streams in the model data set, the seven habitat variables explained 47% of the variation in index of biotic integrity (IBI) scores. To produce the habitat index, the coefficients in the regression were used to weight each of the seven variables. For low-gradient streams in the test data set, the habitat index explained 20% of the variation in IBI scores. A habitat index could not be developed for high-gradient sites, probably due to the low number of sites. Comparison of habitat to IBI scores provides resource managers with a method to evaluate the contribution of habitat quality to the IBI score.

Michigan, Minnesota, Wisconsin↗

USGS1999

Distribution of odonates (dragonflies and damselflies) in the Indiana Dunes National Lakeshore and nearby lands

From 1993 to 1997, 60 species of Anisoptera (dragonflies) and Zygoptera (damselflies) were found in Lake and Porter Counties, Indiana, including Indiana Dunes National Lakeshore, in contrast to 34 species that were recorded historically from this region. We added 17 new species to Lake County's odonate records and 39 new species to the 5 previously recorded in Porter County. Several regionally rare species were collected: Aeshna clepsydra, Enallagma cyathigerum, and Leucorrhina frigida. Nine species listed in the historical records were missing from our collections: Hetaerina americana, Calopteryx aequabilis, Nehalennia irene, Arigomphus furcifer, Argia fumipennis violacea, Gomphus spicatus, Epitheca princeps, Libellula exusta, and Sympetrum semicinctum. These nine species have either declined in the area or they may be found in other habitats after further study. Because few odonate surveys were conducted in northwest Indiana in the past, a poor baseline exists for comparisons of temporal trends in odonate diversity.

Indiana↗

USGS1999

Diatom (Bacillariophyta) community response to water quality and land use

Aquatic algal communities are sensitive to environmental stresses and are used as indicators of water quality. Diatoms were collected from three streams that drain the Great Marsh at Indiana Dunes National Lakeshore. Diatom communities, water chemistry, and land use were measured at each site to test the hypothesis that differences in land use indirectly affect diatom communities, through changes in water quality. Relationships among these variables were examined by correlation, cluster, and detrended correspondence analysis. Several water chemistry variables were correlated to several land-use categories. Diatom species diversity was most variable in disturbed areas with poorer water quality and was correlated with land use and total alkalinity, total hardness, and specific conductance. Sites within each stream were grouped in terms of their diatom assemblage by both cluster and detrended correspondence analysis with but two exceptions in Dunes Creek. Diatom communities in the three streams responded to land use through its effects on water quality. The results of this study demonstrate the use of diatom assemblages as indicators of water quality, which can be linked to land use in a watershed.

Indiana↗

USGS1999

Structure and function of fish communities in the southern Lake Michigan basin with emphasis on restoration of native fish communities

The southern Lake Michigan basin in northwest Indiana possesses a variety of aquatic habitats including riverine, palustrine, and lacustrine systems. The watershed draining this area is a remnant of glacial Lake Chicago and supports fish communities that are typically low in species richness. Composition of the presettlement Lake Michigan fish community near the Indiana Dunes has been difficult to reconstruct. Existing data indicate that the number of native species in the Lake Michigan watershed, including nearshore Lake Michigan, has declined by 22% since the onset of European settlement. Few remnants of natural fish communities exist, and those occur principally in the ponds of Miller Woods, the Grand Calumet Lagoons, and the Little Calumet River. These communities have maintained a relatively diverse assemblage of fishes despite large-scale anthropogenic disturbances in the area, including channelization, massive river redirection, fragmentation, habitat alteration, exotic species invasions, and the introduction of toxic chemicals. Data that we collected from 1985 to 1996 suggested that the Grand Calumet River has the highest proportion of exotic fish species of any inland wetland in northwest Indiana. Along the Lake Michigan shoreline, another group of exotics (e.g., round goby, alewife, and sea lamprey) have affected the structure of native fish communities, thereby altering lake ecosystem function. Stocking programs contribute to the impairment of native communities. Nonindigenous species have restructured the function of Lake Michigan tributaries, causing disruptions in trophic dynamics, guild structure, and species diversity. Several fish communities have been reduced or eliminated by the alteration and destruction of spawning and nursery areas. Degradation of habitats has caused an increase in numbers and populations of species able to tolerate and flourish when confronted with hydrologic alteration. Fish communities found on public lands in northwest Indiana generally are of lower biological integrity, in terms of structure and function, than those on private lands and are not acting as refugia for native fish populations. Stocking of nonindigenous species should be evaluated to enable the restoration of native fish communities on public lands. Habitat quality will need to be improved and land-use modifications decreased or reversed in order to restore or slow the decline in native fish communities.

Indiana↗

USGS1998

Organochlorines, mercury, and selenium in great blue heron eggs from Indiana Dunes National Lakeshore, Indiana

In 1993, 20 great blue heron (Ardea herodias; GBH) eggs (one per nest) were collected from a colony at the Indiana Dunes National Lakeshore, Indiana (INDU). The eggs were artificially incubated until pipping and were then analyzed for organochlorines, mercury, and selenium. Livers of embryos were analyzed for hepatic microsomal ethoxyresorufin-O-dealkylase (EROD) activity. Brains were measured for asymmetry. Egg-laying began in early April and the mean clutch size was 4.2 eggs per clutch. Organochlorine concentrations were generally low (geometric mean p,p’-DDE = 1.6 /μg/g wet weight; polychlorinated biphenyl [PCB] = 4.9 μg/g); however, one egg had elevated concentrations of p,p -DDE (13 /μg/g) and PCBs (56 /μg/g). EROD activity in the embryos analyzed from INDU was not elevated. The frequency (11%) of brain asymmetry was low. Eggshells averaged 3.4% thinner than eggshells collected prior to the use of DDT. Mercury (geometric mean = 0.9 μg/g dry weight) concentrations in GBH eggs were within background levels. Selenium (4.0 μg/g dry weight) concentrations in eggs were above background levels, but below a concentration threshold associated with reproductive impairment.

Journal of Great Lakes Research↗

USGS1993

Intrafen and interfen variation of Indiana fens: water chemistry

This study establishes a baseline of water chemistry information for selected Indiana fens over the course of one year. Fens are peatlands fed by groundwater seepage and are characterized by their dominant plant communities. Most of the fens discussed in this paper are located on property controlled and protected by the State of Indiana or the Federal government. Comparisons were made of variability in water chemistry data between fens located in the same area and those located some distance away. This survey indicated extensive variability in fen water chemistry with greater variability in water chemistry between fens in separate locations than in yearly variation within individual fens.

Proceedings of the Indiana Academy of Science↗