Sean J. Zeiger

Lincoln University of Missouri · Department of Agriculture and Environmental Sciences

Anthropogenic and natural disturbances to freshwater quantity and quality is a greater issue for society than ever before. To successfully restore water resources in impaired watersheds requires understanding the interactions between hydrology, climate, land use, water quality, ecology, social and economic pressures. Current understanding of these...

Karst terrain confounds efforts to parameterize and calibrate The Soil and Water Assessment Tool (SWAT). The purpose of this study was to use SWAT to simulate long-term natural (e.g. climate) and human (e.g. land use) impacts to streamflow, sediment and nutrient loading in a karst catchment. Sub-objectives were to: (1) perform a rigorous model perf...

There is an immediate need to use available modeling tools to quantify environmental flows targets where changing climate and human activity has altered hydroecologically important streamflow regimes. A model performance assessment was undertaken using observed data collected from five nested gauging sites in a mixed land use watershed of the centr...

There is an immediate need to quantify and model environmental flows in watersheds where changing climate and human activity has altered hydroecologically important streamflow regimes, water quality variables, and physical habitat. A model performance assessment was undertaken using observed data collected from five nested gauging sites in a mixed...

A Soil and Water Assessment Tool (SWAT) scenario modeling study. Results show differences between: (1) observed environmental flows, and (2) SWAT simulated pre-settlement environmental flows at five nested gauging sites in Hinkson Creek Watershed, a mixed-land-use watershed of the central US.

Land managers are often inadequately informed to make management decisions in contemporary watersheds, in which sources of impairment are simultaneously shifting due to the combined influences of land use change, rapid ongoing human population growth, and changing environmental conditions. There is, thus, a great need for effective collaborative ad...

Land use can radically degrade stream physical habitat via alterations to channel geomorphology and sedimentological characteristics. However, independent and combined influences such as those of agricultural and urban land use practices on channel geomorphology and substrate composition remain poorly understood. To further understanding of mixed l...

Flow frequency is an important hydrologic statistic to consider in environmental flows assessment. However, there is a paucity of focused interdisciplinary hydrologic assessments that quantify human development influence on flow frequency of small streams (drainage area < 282 km²). Relationships between urban land use and land cover (LULC) and flow...

There is an ongoing need for multidisciplinary investigations that will lead to policy changes that target and reduce natural and anthropic alterations to hydroecological indices important for regional environmental flows management. The hydroecological indices assessed in this study were all deemed ecologically relevant due to causal linkages with...

Competing influences of climate, watershed characteristics, and human activities can confound classic hydrologic process assumptions and, therefore, management efforts in mixed-land-use watersheds. Seven water years (WY2009–2015) of sub-hourly rainfall and stream flow data were collected from five nested gauging sites in a mixed-land-use watershed...

Determining environmental flow requirements to sustain aquatic ecosystem health remains a challenge. The purpose of this research was to quantify the extent of current flow alterations relative to baseline hydrologic conditions of a simulated historic flow regime prior to anthropogenic flow disturbance (i.e., pre-settlement flows). Results allowed...

The purpose of this research was to assess the difference between Soil and Water Assessment Tool (SWAT) simulated pre-development and contemporary developed loading regimes in a mixed-land-use watershed of the central United States (US). Native land cover based on soil characteristics was used to simulate pre-development loading regimes using The S...

An Ozarks Environmental Water Resources Institute (OEWRI) technical report was prepared to guide watershed management efforts of Watershed Committee of the Ozarks. The SWAT model was used to simulate bacteria (E. coli) loading in Little Sac Watershed, Missouri. Outcomes of Best Management Practices (BMP's) were showcased. Results highlight potent...

There is a need for research that advances understanding of flow alterations in contemporary watersheds where natural and anthropogenic interactions can confound mitigation efforts. Event-based flow frequency, timing, magnitude, and rate of change were quantified at five-site nested gauging sites in a representative mixed-land-use watershed of the...

Rapid urbanization and agricultural development have altered flow and pollutant loading regimes resulting in poorly understood pollutant transport regimes and inadequately conceived management practices. Four years of hydrologic and water quality data (i.e. stream flow, suspended sediment, nitrate, nitrite, total ammonium, total inorganic nitrogen,...

Rapid urbanization and agricultural development have altered flow and pollutant loading regimes resulting in poorly understood pollutant transport regimes and inadequately conceived management practices. Four years of hydrologic and water quality data (i.e., stream flow, suspended sediment, nitrate, nitrite, total ammonium, total inorganic nitrogen...

Accurate mean areal precipitation (MAP) estimates are essential input forcings for hydrologic models. However, the selection of the most accurate method to estimate MAP can be daunting because there are numerous methods to choose from (e.g., proximate gauge, direct weighted average, surface-fitting, and remotely sensed methods). Multiple methods (n...

A nested-scale watershed study design was used to monitor water quantity and quality of an impaired 3rd order stream in a rapidly urbanizing mixed-land-use watershed of the central USA. Grab samples were collected at each gauging site (n=836 samples x 5 gauging sites) and analyzed for suspended sediment, total phosphorus, and inorganic nitrogen spe...

The impacts of land use on flow and pollutant loading regimes are poorly understood in mixed-land-use watersheds. Stream water quantity and quality was monitored using a nested-scale experimental watershed study design in a rapidly urbanizing mixed-land-use watershed of the central USA. Agricultural land use decreased by 18.4% and urban land use in...

Advancements in watershed management are both a major challenge, and urgent need of this century. The experimental watershed study (EWS) approach provides critical baseline and long-term information that can improve decision-making, and reduce misallocation of mitigation investments. Historically, the EWS approach was used in wildland watersheds to...

Impacts of urban land use can include increased stormwater runoff temperature (Tw) leading to receiving water quality impairment. There is therefore a need to target and mitigate sources of thermal pollution in urban areas. However, complex relationships between urban development, stormwater runoff and stream water heating processes are poorly unde...

To improve quantitative understanding of mixed-land-use impacts on nutrient yields, a nested-scale experimental watershed study design (n = 5) was applied in a 303(d), clean water act impaired urbanizing watershed of the lower Missouri River Basin, USA. From 2010–2013, water samples (n = 858 sample days per site) were analyzed for total inorganic n...

Hydrologic models that rely on site specific linear and non-linear regression water temperature (Tw) subroutines forced solely with observed air temperature (Ta) may not accurately estimate Tw in mixed-use urbanizing watersheds where hydrogeological and land use complexity may confound common Tw regime assumptions. A nested-scale experimental water...