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Babbar-Sebens M.,Oregon State University | Barr R.C.,Indiana University - Purdue University Indianapolis | Tedesco L.P.,Wetlands Institute | Anderson M.,U.S. Environmental Protection Agency
Ecological Engineering | Year: 2013

Wetland ecosystems are considered as potential ecological solutions for increasing the capacity of watersheds to store runoff waters upstream, and thereby, decrease risk of downstream flooding. Especially in tile-drained agricultural landscapes, wetlands constructed to intercept these tiles can serve as storage basins for agricultural runoff, leading to both reduction in peak runoff flows and diminished transport of agricultural nutrients. The objective of this study was to develop a watershed-scale methodology for identifying potential sites for wetlands in a tile-drained landscape in the Midwestern USA, and for optimizing the spatial distribution of these wetlands for reductions in peak runoff flows. The benefits of this methodology is demonstrated by using it for selecting appropriate wetland restoration and/or creation sites in Eagle Creek Watershed (ECW), located 10 miles northwest of Indianapolis, IN, USA. Results show that a large number of potential sites could be identified (e.g., 2953 sites in ECW), and with a choice of effective wetland design parameters and with spatial optimization of their areas, locations, and drainage areas, it is possible to achieve significant peak flow reductions with fewer sites and smaller wetlands. © 2012 Elsevier B.V.

Bruder S.,Indiana University - Purdue University Indianapolis | Babbar-Sebens M.,Oregon State University | Tedesco L.,Wetlands Institute | Soyeux E.,Veolia
Environmental Monitoring and Assessment | Year: 2014

Mechanistic modeling of how algal species produce metabolites (e.g., taste and odor compounds geosmin and 2-methyl isoborneol (2-MIB)) as a biological response is currently not well understood. However, water managers and water utilities using these reservoirs often need methods for predicting metabolite production, so that appropriate water treatment procedures can be implemented. In this research, a heuristic approach using Adaptive Network-based Fuzzy Inference System (ANFIS) was developed to determine the underlying nonlinear and uncertain quantitative relationship between observed cyanobacterial metabolites (2-MIB and geosmin), various algal species, and physical and chemical variables. The model is proposed to be used in conjunction with numerical water quality models that can predict spatial-temporal distribution of flows, velocities, water quality parameters, and algal functional groups. The coupling of the proposed metabolite model with the numerical water quality models would assist various utilities which use mechanistic water quality models to also be able to predict distribution of taste and odor metabolites, especially when monitoring of metabolites is limited. The proposed metabolite model was developed and tested for the Eagle Creek Reservoir in Indiana (USA) using observations over a 3-year period (2008-2010). Results show that the developed models performed well for geosmin (R 2=0.83 for all training data and R 2=0.78 for validation of all 10 data points in the validation dataset) and reasonably well for the 2-MIB (R 2=0.82 for all training data and R 2=0.70 for 7 out of 10 data points in the validation dataset). © 2013 Springer Science+Business Media.

Krause Camilo B.,Umweltbundesamt FG Trinkwasserressourcen und Wasseraufbereitung | Matzinger A.,Kompetenzzentrum Wasser Berlin KWB | Litz N.,Umweltbundesamt FG Trinkwasserressourcen und Wasseraufbereitung | Tedesco L.P.,Wetlands Institute | Wessolek G.,TU Berlin
Ecological Engineering | Year: 2013

The present laboratory study tests the hypothesis that straw-bark mulch bioreactors are capable of concurrently retaining nitrate (NO3-) and the herbicides atrazine or bentazone at short hydraulic residence times (HRT). In a 1 year column experiment at HRT of ~4h three organic carbon sources, straw of common wheat (Triticum aestivum L.), bark mulch of pine tree (Pinus sp.) and a mixture of both materials, showed high reduction of continuously dosed NO3- (100mgL-1) with average denitrification rates of 23.4g-Nd-1m-3, 8.4g-Nd-1m-3 and 20.5g-Nd-1m-3, respectively. Under denitrifying conditions, fast and substantial retention of continuously dosed atrazine (20μgL-1) was observed with estimated dissipation times (DT50) between 0.12 and 0.49 days in the straw-bark mulch bioreactor. In parallel batch experiments, it could be confirmed that atrazine retention is based on adsorption to bark mulch and on degradation processes supplied by the organic materials as continual sources of carbon. In contrast, bentazone was not significantly reduced under the experimental conditions. While aging of materials was clearly observed in a reduction of denitrification by 60-70% during the experiment, systems still worked very well until the end of the experiment. The results indicate that the combined use of straw and bark mulch could increase the efficiency of mitigation systems, which are installed to improve the quality of drainage water before its release to surface waters. Further, the addition of these materials has the potential of parallel retention of NO3- and less mobile herbicides like atrazine, even during high flow events, as expected at the outlet of agricultural drainage systems. High removal is expected for mitigation system designed to remain saturated most of the time, whereas bioreactors that run periodically dry are not covered by this study. However, further experiments with the tested materials at technical or field scale under more realistic climate conditions need to be carried out. © 2013.

Ferguson L.M.,Clemson University | Ferguson L.M.,Wetlands Institute | Norton T.M.,Jekyll Island Authoritys Georgia Sea Turtle Center | Cray C.,University of Miami | And 2 more authors.
Journal of Zoo and Wildlife Medicine | Year: 2014

Health evaluations of brown pelican (Pelecanus occidentalis) nestlings from three colonies along the Atlantic coast of the southeastern United States were performed in 2005, 2007, and 2008. The primary objective of this study was to establish baseline data for hematologic, biochemical, and serologic values from a relatively healthy population of free-living pelicans during early chick development. Relationships among health variables and colony site, ectoparasite infestation, sex, and body condition index were also evaluated. Reference intervals are presented for health variables, including novel analytes for the species, as well as a comparison of these results with previously published values for wild pelicans. No significant relationships were found between health variables and nestling sex or body condition; however, differences between colony sites and the presence of ectoparasites were detected. The inclusion of health assessments as a regular component of management programs for seabirds can provide data to better understand the effect to species of concern when drastic changes occur to the population and its environment. © Copyright 2014 by American Association of Zoo Veterinarians.

Song K.,Indiana University - Purdue University Indianapolis | Song K.,Chinese Academy of Sciences | Li L.,Indiana University - Purdue University Indianapolis | Li S.,Indiana University - Purdue University Indianapolis | And 7 more authors.
IEEE Transactions on Geoscience and Remote Sensing | Year: 2014

Accurate remote estimation of chlorophyll-A (CHL) concentration for turbid inland waters is a challenging task due to their optical complexity. In situ spectra (n = 666) measured with ASD and Ocean Optics spectrometers from three drinking water sources in Indiana, USA, were used to calibrate the partial least squares model (PLS), artificial neural network model (ANN), and the three-band model (TBM) for CHL estimates; model performances are validated with three independent datasets (n = 360) from China. The PLS-ANN model resulted in accurate model calibration (R2 = 0.94; Range = 0.2-296.6 μg/l of CHL), outperforming the PLS (R2 = 0.87), ANN (R2 = 0.91), and TBM (R2 = 0.86). With an independent validation dataset, the PLSANN yielded relatively high accuracy (RMSE: 6.12 μg/l; rRMSE = 42.12%; range = 0.45-97.2 μg/l of CHL), while TBM yielded acceptable accuracy (RMSE: 8.85 μg/l; rRMSE = 63.21%). With simulated ESA/MERIS and EO-1/Hyperion spectra, the PLSANN also (MERIS: R2 = 0.84; Hyperion: R2 = 0.88) outperforms the TBM (MERIS: R2 = 0.69; Hyperion: R2 = 0.76) for model calibration. For validation, the PLS-ANN achieves good performance with simulated spectra (MERIS: RMSE = 7.83 μg/l, rRMSE = 48.79%; Hyperion: RMSE = 6.98 μg/l, rRMSE = 45.57%) as compared to the TBM (MERIS: RMSE = 10.39 μg/l, rRMSE = 68.92%; Hyperion: RMSE = 9.54 μg/l, rRMSE = 65.35%). Nevertheless, considering the large and diverse datasets, the TBM is a robust semiempirical algorithm. Based on our observations, both the PLS-ANN and TBM are effective approaches for CHL estimation in turbid waters. © 2013 IEEE.

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