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Item Analysis of Mercury Concentrations in Indiana Soil to Evaluate Patterns of Long-Term Atmospheric Mercury Deposition(2013-01-09) Crewe, Julie R.; Filippelli, Gabriel M.; Babbar-Sebens, Meghna; Risch, Martin R.Mercury (Hg) has proven to be a risk to the public, mainly through the consumption of fish. Because of this, many fish consumption advisories have been issued in Indiana. Although much is known about the global cycle of mercury, little is known about how local and regional emission sources of mercury impact local and regional mercury cycling. This study’s objective was to determine the scope of mercury concentration in central Indiana by using a broad grid of soil mercury measurements. Sampling was designed to capture the net retained mercury content in soils, and to determine whether spatial patterns in exist in soil mercury contents that could be related to emission sources of mercury and post-emission transport patterns from wind. Results from this study revealed significant differences in mercury concentrations for soils in central Indiana. The core of the study area, concentrated in the urban area of Indianapolis, exhibited soil mercury contents that were 20 times higher than values in the outskirts of the study area. The spatial pattern resembled a bulls-eye shape centered on Indianapolis, and with comparison to the reported Hg emission from local sources, including a coal-fired power plant, indicates a strong regional deposition signal linked to those emission sources but marked by wind-driven transport to the northeast. This effect of local emission sources resulting in local deposition indicates that limiting mercury emissions will have a net beneficial impact on local environmental quality and human health.Item Applied Solutions for Water Resource Challenges: Floods, Contamination and Upland Water Storage(Office of the Vice Chancellor for Research, 2011-04-08) Smith, Amy; Tedesco, Lenore P.; Babbar-Sebens, Meghna; Barr, Robert C.; Hall, Bob E.; Stouder, MichaelThe Center for Earth and Environmental Science, an IUPUI Signature Center, is working on a series of water resources problems and creating solutions. A series of collaborative projects are underway with the HUD, FEMA, the Office of Community and Rural Affairs, the United States Geological Survey, the Indiana State Department of Agriculture, and an international corporate partner in Berlin, KompetenzZentrum Wasser Berlin. Flood Erosion Hazard Program CEES, the USGS, and Polis are working with HUD and the Office of Community and Rural Affairs, though the Indiana Silver Jackets, to create tools for the State of Indiana to incorporate flood erosion hazard risk assessments into community planning. Flooding remains the most costly natural hazard in the US and Indiana. Flood losses continue to rise despite billions of dollars in mitigation. The causes are complex and related to land use, infrastructure design and climate change. Following the June 2008 floods in Indiana, 39 counties were listed as Federal disaster areas. In early 2005, 90% of Indiana counties were declared federal disaster areas after heavy rains fell on saturated soil. There have been seven major regional flooding events since the “Great flood of 1913”. The frequency of large floods appears to be increasing. Four of the eight major floods have occurred since 1982 and the last two occurred in 2005 and 2008. From 1998 through 2007, total insured flood losses in Indiana exceeded $39.8 million. While more restricted in area than the floods of 2008; record flooding occurred again throughout central and southern Indiana in early 2011 following heavy rains in February and March. Traditional flood protection usually consists of three components: flood control reservoirs, urban levees/floodwalls, and agricultural levees. These traditional flood protection methods are focused on one aspect of flooding – inundation. However, the largest single source of flood losses, both in terms of cost and number of affected persons, is damage to transportation infrastructure. Fluvial erosion is a principal cause of this damage. This significant flood-related natural hazard – the “fluvial erosion hazard” (FEH) – is not a specific component of State and local mitigation programs. This project aims to generate the tools for inclusion of FEH into statewide and local community planning. Aquisafe II - Performance Analysis of Selected Mitigation Systems Used to Attenuate Non-Point Source Agricultural Pollution Aquisafe is an international research collaboration with Veolia Environment based in Paris, their corporate partner in Berlin (KompetenzZentrum Wasser – Berlin Center of Competence for Water), the German Federal Environmental Agency, German university partners, and French quasi-governmental agencies in Brittany, France. The project goals are to create new mitigation systems to capture and treat polluted agricultural water running off farm fields prior to flowing into area streams, especially those used for drinking water supplies. The contaminants of specific concern are nutrients (nitrogen and phosphorus) and pesticides (atrazine – a corn-herbicide with potential endocrine disrupting effects). We are testing 2-stage, constructed wetlands in Indianapolis, Indiana and Brittany, France that have been designed to intercept and convert contaminants to harmless compounds. Site designs are guided by laboratory technical scale experiments conducted in Berlin that identified the hydrologic retention times and suitable sources of organic carbon necessary for mitigating contaminants. Construction of the experimental systems will begin in April in the Eagle Creek Watershed in cooperation with a private farmer with initial results expected this summer.Item Center for Earth and Environmental Science: A Program of Excellence in Water Resources Research(Office of the Vice Chancellor for Research, 2010-04-09) Tedesco, Lenore P.; Babbar-Sebens, MeghnaResearch and training into the impacts of environmental insults on water systems and the links between water resources and human health are critical needs nationally and internationally. IUPUI is in an excellent position to take on a leadership role in scholarship and teaching about water quality and health. CEES has built its program and reputation around excellence in water resources and ecosystem restoration research. Key to our success has been the development of a research network founded on strong corporate, governmental and community partnerships and collaborations. This framework is strengthened by the mutual benefit realized by all partners and helps to support IUPUI’s core value of community engagement as an urban research university. In order to maximize the efficient use of resources, CEES is pursuing four strategic objectives in a manner that will further the universities goals of pursuing excellence in 1) research, scholarship and creative activity, 2) teaching and learning, and 3) civic engagement while also enhancing the resource base of the university. The Center places the highest priority on four strategic initiatives: 1. The Center will engage in cutting-edge research and training for mixed agricultural and urban watersheds 2. Evaluate and assess watershed Best Management Practices targeting atrazine, nutrients and emerging contaminants and pathogens 3. Establish a K-12 technology based science education program in water, air and energy 4. Work with state agencies to identify watershed issues associated with Major Moves and other economic development initiatives, the standards to be applied and training needs To this end, the Signature Center program in CEES has focused on building new collaborations with water resources and human health risks. Signature Center funding has provided for new faculty member Dr. Meghna Babbar-Sebens to join the Earth Sciences faculty as an Assistant Professor. Her research is focused on the modeling of water-borne contaminants, and decision support systems for management of water quality and associated ecological and human health risks. Dr. Babbar-Sebens research focuses on a) analysis of uncertainty when models are used to conduct spatially referenced systems-scale environmental assessments, b) incorporation of uncertainty analysis within decision support systems used for risk assessment and management, and c) optimization of water resources planning and management strategies for emergency response and water-borne disease prevention.Item Combining Multivariate Statistical Methods and Spatial Analysis to Characterize Water Quality Conditions in the White River Basin, Indiana, U.S.A.(2011-02-25) Gamble, Andrew Stephan; Babbar-Sebens, Meghna; Tedesco, Lenore P.; Peng, HanxiangThis research performs a comparative study of techniques for combining spatial data and multivariate statistical methods for characterizing water quality conditions in a river basin. The study has been performed on the White River basin in central Indiana, and uses sixteen physical and chemical water quality parameters collected from 44 different monitoring sites, along with various spatial data related to land use – land cover, soil characteristics, terrain characteristics, eco-regions, etc. Various parameters related to the spatial data were analyzed using ArcHydro tools and were included in the multivariate analysis methods for the purpose of creating classification equations that relate spatial and spatio-temporal attributes of the watershed to water quality data at monitoring stations. The study compares the use of various statistical estimates (mean, geometric mean, trimmed mean, and median) of monitored water quality variables to represent annual and seasonal water quality conditions. The relationship between these estimates and the spatial data is then modeled via linear and non-linear multivariate methods. The linear statistical multivariate method uses a combination of principal component analysis, cluster analysis, and discriminant analysis, whereas the non-linear multivariate method uses a combination of Kohonen Self-Organizing Maps, Cluster Analysis, and Support Vector Machines. The final models were tested with recent and independent data collected from stations in the Eagle Creek watershed, within the White River basin. In 6 out of 20 models the Support Vector Machine more accurately classified the Eagle Creek stations, and in 2 out of 20 models the Linear Discriminant Analysis model achieved better results. Neither the linear or non-linear models had an apparent advantage for the remaining 12 models. This research provides an insight into the variability and uncertainty in the interpretation of the various statistical estimates and statistical models, when water quality monitoring data is combined with spatial data for characterizing general spatial and spatio-temporal trends.Item Control Theoretical Modeling of Trust-Based Decision Making in Food-Energy-Water Management(Springer, 2021) Uslu, Suleyman; Kaur, Davinder; Rivera, Samuel J.; Durresi, Arjan; Babbar-Sebens, Meghna; Tilt, Jenna H.; Computer and Information Science, School of ScienceWe propose a hybrid Human-Machine decision making to manage Food-Energy-Water resources. In our system trust among human actors during decision making is measured and managed. Furthermore, such trust is used to pressure human actors to choose among the solutions generated by algorithms that satisfy the community’s preferred trade-offs among various objectives. We model the trust-based loops in decision making by using control theory. In this system, the feedback information is the trust pressure that actors receive from peers. Using control theory, we studied the dynamics of the trust of an actor. Then, we presented the modeling of the change of solution distances. In both scenarios, we also calculated the settling times and the stability using the transfer functions and their Z-transforms as the number of rounds to show whether and when the decision making is finalized.Item Coupled biogeochemical cycles in riparian zones with contrasting hydrogeomorphic characteristics in the US Midwest(2013-12-11) Liu, Xiaoqiang; Vidon, Philippe G.; Jacinthe, Pierre-Andre; Babbar-Sebens, MeghnaNumerous studies have investigated the fate of pollutants in riparian buffers, but few studies have focused on the control of multiple contaminants simultaneously in riparian zones. To better understand what drives the biogeochemical cycles of multiple contaminants in riparian zones, a 19-month study was conducted in riparian buffers across a range of hydrogeomorphic (HGM) settings in the White River watershed in Indiana. Three research sites [Leary Webber Ditch (LWD), Scott Starling (SS) and White River (WR)] with contrasting hydro-geomorphology were selected. We monitored groundwater table depth, oxidation reduction potential (ORP), dissolved oxygen (DO), dissolved organic carbon (DOC), NO3-, NH4+, soluble reactive phosphorus (SRP), SO42- , total Hg and methylmercury (MeHg). Our results revealed that differences in HGM conditions translated into distinctive site hydrology, but significant differences in site hydrology did not lead to different biogeochemical conditions. Nitrate reduction and sulfate re-oxidation were likely associated with major hydrological events, while sulfate reduction, ammonia and methylmercury production were likely associated with seasonal changes in biogeochemical conditions. Results also suggest that the LWD site was a small sink for nitrate but a source for sulfate and MeHg, the SS site was a small sink for MeHg but had little effect on NO3-, SO42- and SRP, and the WR was an intermediate to a large sink for nitrate, an intermediate sink for SRP, and a small source for MeHg. Land use and point source appears to have played an important role in regulating solute concentrations (NO3-, SRP and THg). Thermodynamic theories probably oversimplify the complex patterns of solute dynamics which, at the sites monitored in the present study, were more strongly impacted by HGM settings, land use, and proximity to a point source.Item Effect of Stakeholder Attitudes on the Optimization of Watershed Conservation Practices(2013-01-30) Piemonti, Adriana Debora; Babbar-Sebens, Meghna; Jacinthe, Pierre-Andre; Mukhopadhyay, Snehasis; Luzar, E. Jane, 1951-Land use alterations have been major drivers for modifying hydrologic cycles in many watersheds nationwide. Imbalances in this cycle have led to unexpected or extreme changes in flood and drought patterns and intensities, severe impairment of rivers and streams due to pollutants, and extensive economic losses to affected communities. Eagle Creek Watershed (ECW) is a typical Midwestern agricultural watershed with a growing urban land-use that has been affected by these problems. Structural solutions, such as ditches and tiles, have helped in the past to reduce the flooding problem in the upland agricultural area. But these structures have led to extensive flooding and water quality problems downstream and loss of moisture storage in the soil upstream. It has been suggested that re-naturalization of watershed hydrology via a spatially-distributed implementation of non-structural and structural conservation practices, such as cover crops, wetlands, riparian buffers, grassed waterways, etc. will help to reduce these problems by improving the upland runoff (storing water temporally as moisture in the soil or in depression storages). However, spatial implementation of these upland storage practices poses hurdles not only due to the large number of possible alternatives offered by physical models, but also by the effect of tenure, social attitudes, and behaviors of landowners that could further add complexities on whether and how these practices are adopted and effectively implemented for benefits. This study investigates (a) how landowner tenure and attitudes can be used to identify promising conservation practices in an agricultural watershed, (b) how the different attitudes and preferences of stakeholders can modify the effectiveness of solutions obtained via classic optimization approaches that do not include the influence of social attitudes in a watershed, and (c) how spatial distribution of landowner tenure affects the spatial optimization of conservation practices on a watershed scale. Results showed two main preferred practices, one for an economic evaluation (filter strips) and one for an environmental perspective (wetlands). A land tenure comparison showed differences in spatial distribution of systems considering all the conservation practices. It also was observed that cash renters selected practices will provide a better cost-revenue relation than the selected optimal solution.Item Exploration and Visualization of Patterns Underlying Multistakeholder Preferences in Watershed Conservation Decisions Generated by an Interactive Genetic Algorithm(Wiley, 2021-05) Piemonti, Adriana Debora; Guizani, Mariam; Babbar-Sebens, Meghna; Zhang, Eugene; Mukhopadhyay, Snehasis; Computer and Information Science, School of ScienceIn multiple watershed planning and design problems, such as conservation planning, quantitative estimates of costs, and environmental benefits of proposed conservation decisions may not be the only criteria that influence stakeholders' preferences for those decisions. Their preferences may also be influenced by the conservation decision itself—specifically, the type of practice, where it is being proposed, existing biases, and previous experiences with the practice. While human-in-the-loop type search techniques, such as Interactive Genetic Algorithms (IGA), provide opportunities for stakeholders to incorporate their preferences in the design of alternatives, examination of user-preferred conservation design alternatives for patterns in Decision Space can provide insights into which local decisions have higher or lower agreement among stakeholders. In this paper, we explore and compare spatial patterns in conservation decisions (specifically involving cover crops and filter strips) within design alternatives generated by IGA and noninteractive GA. Methods for comparing patterns include nonvisual as well as visualization approaches, including a novel visual analytics technique. Results for the study site show that user-preferred designs generated by all participants had strong bias for cover crops in a majority (50%–83%) of the subbasins. Further, exploration with heat maps visualization indicate that IGA-based search yielded very different spatial patterns of user-preferred decisions in subbasins in comparison to decisions within design alternatives that were generated without the human-in-the-loop. Finally, the proposed coincident-nodes, multiedge graph visualization was helpful in visualizing disagreement among participants in local subbasin scale decisions, and for visualizing spatial patterns in local subbasin scale costs and benefits.Item Interactive genetic algorithm for user-centered design of distributed conservation practices in a watershed: An examination of user preferences in objective space and user behavior(Wiley, 2017-05) Piemonti, Adriana Debora; Babbar-Sebens, Meghna; Mukhopadhyay, Snehasis; Kleinberg, Austin; Computer and Information Science, School of ScienceInteractive Genetic Algorithms (IGA) are advanced human-in-the-loop optimization methods that enable humans to give feedback, based on their subjective and unquantified preferences and knowledge, during the algorithm's search process. While these methods are gaining popularity in multiple fields, there is a critical lack of data and analyses on (a) the nature of interactions of different humans with interfaces of decision support systems (DSS) that employ IGA in water resources planning problems and on (b) the effect of human feedback on the algorithm's ability to search for design alternatives desirable to end-users. In this paper, we present results and analyses of observational experiments in which different human participants (surrogates and stakeholders) interacted with an IGA-based, watershed DSS called WRESTORE to identify plans of conservation practices in a watershed. The main goal of this paper is to evaluate how the IGA adapts its search process in the objective space to a user's feedback, and identify whether any similarities exist in the objective space of plans found by different participants. Some participants focused on the entire watershed, while others focused only on specific local subbasins. Additionally, two different hydrology models were used to identify any potential differences in interactive search outcomes that could arise from differences in the numerical values of benefits displayed to participants. Results indicate that stakeholders, in comparison to their surrogates, were more likely to use multiple features of the DSS interface to collect information before giving feedback, and dissimilarities existed among participants in the objective space of design alternatives.Item Lead Distribution in Urban Soils: Relationship Between Lead Sources and Children's Blood Lead Levels(2011-06-14) Morrison-Ibrahim, Deborah E.; Filippelli, Gabriel M.; Steele, Gregory; Babbar-Sebens, Meghna; Li, Lin