Ronald R. Regal

Properties and Performance of the Floristic Quality Index in Great Lakes Coastal Wetlands

The Floristic Quality Index (FQI) has been proposed as a tool that can be used to identify areas of high conservation value, monitor sites over time, assess the anthropogenic impacts affecting an area, and measure the ecological condition of an area. FQI is based on the Coefficient of Conservatism (C), which is a numerical score assigned to each plant species in a local flora, primarily from best professional judgment, that reflects the likelihood that a species is found in natural habitats. FQI is computed by multiplying the mean Coefficient of Conservatism (C) by the square root of species richness for an observational unit. Great Lakes coastal wetlands were used to assess the properties and performance of various species richness, Coefficient of Conservatism, and Floristic Quality indices, as well as compare C-value assignments from two U.S. states (Wisconsin and Michigan). FQI and species richness increased with sampling area according to a power function, but C more or less remained constant. Sampling schemes should therefore focus on controlling sampling area and minimally sampling each community type at a site. In some cases, Wisconsin and Michigan assigned different values of C to the same species, highlighting possible effects due to the somewhat subjective nature of C-value assignment. Coefficient of Conservatism and Floristic Quality indices were better at discriminating differences between sites, independent of a condition gradient, than species richness alone, but neither index type outperformed the other. Both types of indices were also found to be acceptable ecological indicators of condition, although Floristic Quality indices consistently outperformed Coefficient of Conservatism indices in this capacity. Regardless of the subjectivity involved with the assignment of C-values and that ‘floristic quality’ is a human concept and not a true ecosystem property, both Coefficient of Conservatism and Floristic Quality indices seem to be effective indicators of condition in Great Lakes coastal wetland

Topological indices: their nature, mutual relatedness, and applications

Abstract During the last two decades a large number of numerical graph invariants (topological indices) have been defined and used for correlation analysis in theoretical chemistry, pharmacology, toxicology, and environmental chemistry. However, no systematic study has been undertaken to determine to what extent these indices are correlated with each other. In the present paper we have carried out a principal component analysis (PCA) of 90 topological parameters derived from 3692 distinct chemicals taken from an environmental database consisting of nearly nineteen thousand compounds. The PCA using the correlation matrix resulted in 10 principal components (PCs) with eigenvalues greater than 1. These ten PCs explained over 92% of the variance in the standardized data. The first four PCs explained over 78% of the variance and the interpretations of these four PCs is given in terms of the chemical structures at the extremes of these PCs.

EFFECTS OF BACILLUS THURINGIENSIS ISRAELENSIS (BTI) AND METHOPRENE ON NONTARGET MACROINVERTEBRATES IN MINNESOTA WETLANDS

We studied the effects of the mosquito larvicides methoprene and Bacillus thuringiensis israelensis (Bti) on the benthic macroinvertebrate communities of 27 wetland ecosystems in Wright County, Minnesota. These larvicides are generally considered safe for nontarget species. After 3 yr of preliminary investigations, including 2 yr of intensive sampling, larvicide treatments were applied during 1991–1993. Nine of the wetlands were experimentally treated with methoprene, which disrupts insect development; an additional set of nine wetlands were treated with Bti, a microbial larvicide; and nine wetlands were left untreated to serve as a control treatment. In general, insecticide treatment had minimal effects on nontarget groups during the first treatment year. However, during 1992, highly significant reductions due to both methoprene and Bti were observed in several insect groups. Predatory insects were reduced on methoprene-treated sites but not Bti-treated sites in 1992. In 1993, treatment with both larvicides resulted in wetland communities that were depauperate in most insects. Although effects were observed broadly across insect taxa, Diptera, which comprised 79% of the insects, were affected most strongly, especially the dipteran suborder Nematocera, which included 71% of total insects and was dominated by Chironomidae. Minimal effects on noninsect macroinvertebrates were observed. Bti- and methoprene-treated sites also showed a reduction in richness of insect genera and an increased tendency to be dominated by one or a few genera. Pretreatment data, collected under drought conditions from the same wetlands, showed that the benthic macroinvertebrate fauna was dominated by mollusks during the drought but became increasingly dominated by insects during the wetter years. On the treated sites, insects remained at low density, very similar to the drought conditions, but the noninsect macroinvertebrates declined on treated sites in the same pattern as on control sites. Both indirect effects and direct toxicity likely contributed to the observed differences. Bti is likely to be directly toxic only to nematoceran Diptera; thus effects of Bti on other insect groups may have resulted from disruption of the invertebrate food web. Methoprene is more broadly toxic; thus observed methoprene effects on nonnematoceran groups may have been due to either direct toxicity or food web effects, or both. The 2–3 yr lag time in response of nontarget insects to larvicide treatment demonstrates the need for long-term studies in wetland ecosystems, and the need to reconsider the conclusions based on previous short-term studies that these larvicides are environmentally safe.

CORRElATION Of SymPTOmS WITh VITAmIN D DEfICIENCy AND SymPTOm RESPONSE TO ChOlECAlCIfEROl TREATmENT: A RANDOmIzED CONTROllED TRIAl

OBJECTIVE To examine the association of symptoms with vitamin D deficiency and symptom response to cholecalciferol treatment in a randomized, double-blind, placebo-controlled trial. METHODS Adult primary care patients in Duluth, Minnesota, were screened for vitamin D deficiency in February 2007. Participants completed questionnaires pertaining to a variety of symptoms, vitamin D intake, and selected medical conditions. Patients with mild to moderate vitamin D deficiency (25-hydroxyvitamin D [25(OH)D], 10-25 ng/mL) participated in a randomized controlled trial (RCT) of vitamin D replacement and its effect on symptoms. Participants were randomly assigned to receive 50 000 units of cholecalciferol (vitamin D3) weekly or placebo for 8 weeks. Patients with severe vitamin D deficiency (25[OH]D <10 ng/mL) were treated in an unblinded fashion, and symptoms were reevaluated post treatment. RESULTS A total of 610 patients underwent initial screening, and 100 patients with mild to moderate vitamin D deficiency participated in the RCT. Thirty-eight severely deficient patients were treated in an unblinded fashion. On initial screening, 46.2% of participants were deficient in vitamin D. Self-reported vitamin D supplementation, milk intake, celiac disease, gastric bypass, and chronic pancreatitis were predictive of vitamin D status. Severely deficient participants reported increased musculoskeletal symptoms, depression (including seasonal), and higher (worse) scores on a fibromyalgia assessment questionnaire. In the RCT, the treated group showed significant improvement in fibromyalgia assessment scores (P = 0.03), whereas the placebo-treated participants did not. Severely deficient patients did not show symptom improvement over the 8-week trial period or when followed up 1 year later. CONCLUSIONS Compared with participants in the placebo group, patients in the treatment group showed mild short-term improvement in the overall fibromyalgia impact score, but did not show significant improvement in most musculoskeletal symptoms or in activities of daily living.

Responsiveness of Great Lakes Wetland Indicators to Human Disturbances at Multiple Spatial Scales: A Multi-Assemblage Assessment

ABSTRACT Developing indicators of ecosystem condition is a priority in the Great Lakes, but little is known about appropriate spatial scales to characterize disturbance or response for most indicators. We surveyed birds, fish, amphibians, aquatic macroinvertebrates, wetland vegetation, and diatoms at 276 coastal wetland locations throughout the U.S. Great Lakes coastal region during 2002–2004. We assessed the responsiveness of 66 candidate indicators to human disturbance (agriculture, urban development, and point source contaminants) characterized at multiple spatial scales (100, 500, 1,000, and 5,000 m buffers and whole watersheds) using classification and regression tree analysis (CART). Non-stressor covariables (lake, ecosection, watershed, and wetland area) accounted for a greater proportion of variance than disturbance variables. Row-crop agriculture and urban development, especially at larger spatial scales, were about equally influential and were more explanatory than a contaminant stress index (CSI). The CSI was an important predictor for diatom indicators only. Stephanodiscoid diatoms and nest-guarding fish were identified as two of the most promising indicators of row-crop agriculture, while Ambloplites rupestris (fish) and Aeshna (dragonflies) were two of the strongest indicators of urban development. Across all groups of taxa and spatial scales, fish indicators were most responsive to the combined influence of row-crop and urban development. Our results suggest it will be critical to account for the influence of potentially important non-stressor covariables before assessing the strength of indicator responses to disturbance. Moreover, identifying the appropriate scale to characterize disturbance will be necessary for many indicators, especially when urban development is the primary disturbance.

The frequency of 47,+21, 47,+18, and 47,+13 at the uppermost extremes of maternal ages: results on 56,094 fetuses studied prenatally and comparisons with data on livebirths

SummaryWe examined the proportions (or so called “rates”) of fetuses with 47,+21, 47,+18, or 47,+13 diagnosed prenatally in women at the upper extremes of age. Our analysis was prompted by results from a large scale European study of amniocentesis which indicated that after increasing exponentially from age 35 years, the proportions of the autosomal trisomies reached a peak at a specific age and then leveled off or declined at the upper end of the age range. We analyzed North American data on 56,075 fetuses studied because of no known cytogenetic risk factor (aside from maternal age). This is the largest series to data. For 47,+21, the data from amniocentesis studies provide no evidence for any drop in the rate of change of proportion with maternal age up to 49 years. There is, if anything, a trend in our data to a steepening in the exponential rate of change at the upper extreme of age (above 46 years). Data from livebirths on the Down syndrome phenotype are at least consistent with an exponential rate of increase in proportion affected up to age 49 years. For 47,+18 our data from prenatal diagnoses are more consistent with an exponential increase up to age 43 years and a level proportion (or “rate”) after that. For 47,+13 no cases were observed above age 42 years, consistent with the drop in proportion affected above this age observed in the European series. We emphasize the possible effect of sampling fluctuation and reporting error upon these apparent trends.

M2 tidal currents in the western North Atlantic

Abstract A number of current meter records collected by the Woods Hole Oceanographic Institution have been examined to determine the structure of M 2 tides in the western North Atlantic. Though the signal to noise ratio is low, a simple picture emerges when sufficiently many records are averaged. At a site north of the Gulf Stream, the tidal current is baroclinic, and concentrated near the surface. The result is consistent with generation of internal tides along the continental slope just to the north. At positions south of the Gulf Stream, the records are too few to conclude more than that the tidal velocities are consistent with high mode internal waves.

Characterization of the androgen‐sensitive MDA‐kb2 cell line for assessing complex environmental mixtures

Synthetic and natural steroidal androgens and estrogens and many other non-steroidal endocrine-active compounds commonly occur as complex mixtures in aquatic environments. It is important to understand the potential interactive effects of these mixtures to properly assess their risk. Estrogen receptor agonists exhibit additivity in mixtures when tested in vivo and in vitro. Little is known, however, concerning possible mixture interactions of androgen receptor agonists. In these studies we used the MDA-kb2 cell line, a human breast cancer cell line with endogenous androgen receptors and a stably transfected luciferase reporter gene construct to quantify the androgenic activity of seven natural and synthetic androgens: 17beta-trenbolone, dihydrotestosterone, methyltestosterone, testosterone, trendione, 17alpha-trenbolone, and androstenedione. We tested combinations of these androgens and compared the observed activity to expected androgenic activity based on a concentration addition model. Our analyses support the hypothesis that androgen receptor agonists cause additive responses in a mixture. Binary mixtures of 17beta-trenbolone with 17beta-estradiol or triclocarban (an anti-microbial found in the environment) were also tested. 17beta-Estradiol induced androgenic activity, but only at concentrations 600-fold greater than those found in the environment. Triclocarban enhanced the activity of 17beta-trenbolone. Additionally, three anti-androgens were each paired with three androgens of varying potencies. The relative potencies of the antagonists were a vinclozolin metabolite (M2) > procymidone > prochloraz regardless of the androgen used. The results of our studies demonstrate the potential utility of the androgen-responsive MDA-kb2 cell line for quantifying the activity of mixtures of endocrine-active chemicals in complex wastes such as municipal effluents and feedlot discharges.

Are Anurans of Great Lakes Coastal Wetlands Reliable Indicators of Ecological Condition

ABSTRACT Frogs and toads (anurans) are sensitive to a variety of anthropogenic stressors and are widely suggested as indicators of ecological condition. We surveyed 220 coastal wetlands along the U.S. shores of the Laurentian Great Lakes and quantified relationships between presence of anuran species and degree of anthropogenic disturbance. Results were used to derive explicit, functional relationships between environmental condition and anuran occurrences. These functions were subsequently used to calculate a multi-species indicator of ecological condition at other (novel) wetlands. Of 14 anuran species observed, spring peeper (Pseudacris crucifer) exhibited the strongest and most consistent relationship with environmental condition across the entire study area. Other species exhibited significant relationships with the environmental gradient, but the direction of association varied geographically or the overall species abundance was very low (e.g., mink frog, Rana septentrionalis). Even if applied to separate ecological provinces (Laurentian Mixed Forest or Eastern Deciduous Forest), multi-species estimates of wetland condition based on anurans are not much better indicators of environmental condition based on human disturbance than are indices based solely on occurrence of spring peeper. Nevertheless, indicators grounded in explicit relationships with environmental stress are superior to traditional measures (e.g., species richness) that combine species with different responses to the stress gradient. At least one anuran species (spring peeper) can contribute meaningfully to the assessment of ecological condition in Great Lakes coastal wetlands; its value as an indicator will be improved if it can be combined with information from other wetland species such as birds, fishes, and vascular plants.

Consideration of geography and wetland geomorphic type in the development of Great Lakes coastal wetland bird indicators

We examined how geographic distribution of birds and their affinities to three geomorphic wetland types would affect the scale at which we developed indicators based on breeding bird communities for Great Lakes coastal wetlands. We completed 385 breeding bird surveys on 222 wetlands in the US portion of the basin in 2002 and 2003. Analyses showed that wetlands within two ecoprovinces (Laurentian Mixed Forest and Eastern Broadleaf Forest) had different bird communities. Bird communities were also significantly different among five lakes (Superior, Michigan, Huron, Erie, and Ontario) and among three wetland types (lacustrine, riverine, barrier-protected). Indicator values illustrated bird species with high affinities for each group (ecoprovince, lake, wetland type). Species with restricted geographic ranges, such as Alder and Willow Flycatchers (Empidonax alnorum and E. traillii), had significant affinities for ecoprovince. Ten bird species had significant affinities for lacustrine wetlands. Analyses on avian guild metrics showed that Lake Ontario wetlands had fewer long-distant migrants and warblers than other lakes. Numbers of short-distant migrants and total individuals in wetlands were higher in the Eastern Broadleaf Forest ecoprovince. Number of flycatchers and wetland obligate birds were not different among provinces, lakes, or wetland type. One potential indicator for wetland condition in Great Lakes wetlands, proportion of obligate wetland birds, responded negatively to proportion of developed land within 1 km of the wetland. We conclude that, although a guild approach to indicator development ameliorates species-specific geographic differences in distribution, individual species responses to disturbance scale will need to be considered in future indicator development with this approach.