Photo of Ying Ouyang

Ying Ouyang

Research Hydrologist
775 Stone Blvd., Thompson Hall, Room 309
Mississippi State, MS 39762
Phone: 662-325-8654
Fax: 662-325-3278

Current Research

Predicting stream discharge, groundwater flow, and sediment/nutrient transport in the Lower Mississippi River Alluvial Valley (LMRAV) as affected by agricultural/forest managements and climate change using watershed models such as HSPF and MODFLOW.  Performing real-time monitoring of tree sap flux, soil water movement, stream discharge, groundwater flow, and water quantity in the soil-tree-stream-groundwater continuum.  Analyzing the long-term meteorological,  hydrological, and water quality data using HYDSTRA model and multi-variant statistical methods such as copula, flow/load duration curve, Mann-Kendall test, principal component analysis, and wavelet analysis.  Developing and applying STELLA-based models to predict woody biomass production and CO2 emission from bioenergy plantations as affected by soil nutrient and water availability as well as by hydrological and climatic conditions.  Developing and applying a STELLA-based model to simultaneously evaluate farm pond water availability and crop irrigation demand in the LMRAV.


Ph.D. in Soil Science (Soil Physics), 1991
Oregon State University
M.S. in Soil Science (Soil Physics), 1987
Oregon State University
B.S. in Soil Chenistry , 1982
South China Agricultural University

Professional Experience

Research Hydrologist, USDA Forest Service, Center for Bottomland Hardwoods Research

As a Research Hydrologist, my major research responsibilities are to: (1) investigate impacts of forest and agricultural management upon water quality and quantity in the Lower Mississippi Alluvial Valley (LMAV) using computer models (e.g., BASINS-HSPF; MODFLOW/MT3D); (2) develop low flow selection method using minimum flows and levels approach in conjunction with Hydstra model; (3) estimate short-rotation woody biomass production in the soil-tree-atmosphere system using STELLA model; (4) evaluate real-time variations and loads of surface water quality in southeast area using Dynamic Data Driven Application System; (5) detect temporal patterns of watershed hydrology and water quality in response to climate change using Wavelet Analysis; (6) identify most important water quality parameters and environmental variables in forest watershed ecosystems using multivariate statistical analysis (e.g., Principal Component Analysis); (7) assess greenhouse gases (i.e., CO2) flux in forest lands using STELLA model; (8) predict pesticide leaching and loading in agricultural soils; and (9) collaborate with faculty members from Mississippi State University for scientific publications and grant applications as well as serve as graduate student committee members.

Environmental Scientist , St. Johns River Water Management District of Florida

As an Environmental Scientist in water quality and watershed hydrology, my responsibilities were to apply complex computer models, statistical techniques, computational algorithms, and basin-scale field measurements for analyzing surface, wetland, and ground water quality; investigate groundwater discharge, wetland attenuation, and surface load of contaminants, excess nutrients, and sediments into the St. Johns River (SJR) for the purpose of TMDL refinement; ascertain river flow and groundwater drawdown hydrology for water supply impact study; evaluate water use and nutrient application efficiencies in agricultural ecosystems; prepare reports and manuscripts for peer-reviewed publications; develop research projects and manage contracts; and mentor field workers for surface and ground water sampling. During my 12 years' employment at the St. Johns River Water Management District, I had completed the following major projects: (1) modified watershed models (e.g., BASINS-HSPF, GLEAMS, GIS-WAM) for simulating surface water runoff, sediment/contaminant and Hg transport, and total organic carbon load into the SJR; (2) applied the Storm Water Management Model (SWMM) to evaluate surface water runoff, sediment transport, and pollutant loading into the Ortega River and Julington Creek for different land use conditions (e.g., agricultural, forested, urbanization, and industrial lands); (3) performed 3D kriging (geostatistical) analysis on spatial and temporal variations of sediment contaminants using ISATIS model; (4) performed multiple regression on water quality monitoring data for N, P, refractory and labile TOC, and water color in related to basin-scale land uses; (5) applied the principal component analysis to evaluate the SJR basin water quality parameters and monitoring networks; (6) quantified groundwater nutrient discharges into the SJR using field data, Visual MODFLOW/MT3D models, and system dynamic model (STELLA); and (7) applied STELLA model for simulating phytoremediation of contaminants that includes the processes of leaf water evapotranspiration, xylem and phloem chemical transport, and root chemical uptake.

Professional Organizations

  • American Institute of Hydrology, Professional Hydrologist (2002—Current)
  • American Geophysical Union, Member (1991—Current)
  • Soil Science Society of America, Member (1989—Current)

Awards and Recognition

Recipient of Robert G. Wetzel Award for Water Quality from American Institute of Hydrology, 2021
The Wetzel award recognizes individuals who have made outstanding contributions in the field of water quality.
Fellow of Soil Science Society of America, 2019
Fellow is the highest recognition bestowed by the Soil Science Society of America. Up to 0.3 percent of the Society’s active and emeritus members may be elected Fellow.
Certificate of appreciation for work as Associate Editor, 2010
Certificate of appreciation from the American Society of Agronomy/Crop Science Society of America/Soil Science Society of America for work as Associate Editor of the Journal of Environmental Quality for six years (two terms) in 2010.
Ten years service award, 2009
Ten years service award by the St. Johns River Water Management District, Florida, 2009.

Featured Publications and Products


Research Highlights

Estimating impacts of extreme rainfall events for local watersheds (2018)
SRS-2018-45 Many future climate scenarios project impacts of climate variability on water quantity and quality. However, these scenarios may not be accurate and do not have flexibility for local and small watershed analyses. They are not able to answer questions such as: what will happen to stream flow, water quality, and water availability for a given local watershed if extreme rainfall events such as very dry summers and wet winters occur in the next ten years? This information is crucial to state and local water resource managers and stakeholders for implementing adaptive management practices on crop and forest lands.   

Estimating the ratio of pond size to irrigated crop land: A tool to conserve groundwater resources in Mississippi (2017)
SRS-2017-167 Groundwater withdrawals in the Mississippi Delta region and around the nation have increased dramatically since the last century, resulting in the depletion of water resources from subsurface aquifers. Although more on-farm water storage ponds have been constructed in recent years to mitigate groundwater depletion in Mississippi, little effort has been devoted to addressing the question of how many hectares (1 hectare = 2.47 acres) of crop land can be irrigated with water from one hectare of agricultural pond. Forest Service scientists developed a computer modeling tool to address this need.