Kaushal, Sujay: University of Maryland (Project Lead)
Tzortziou, Maria: CCNY City University of New York / Columbia University LDEO (Institution Lead)
Project Funding:
2012 - 2014
NRA: 2010 NASA: Carbon Cycle Science
Funded by NASA
Abstract:
Carbon (C) fluxes are rapidly increasing in many streams and rivers globally. In the U.S., agricultural activities and urbanization have substantially increased fluxes of inorganic and organic C in major rivers and estuaries. These elevated C fluxes have important consequences for regional watershed C budgets, drinking water quality and disinfection by-product formation, and regulating ecosystem processes. Although watershed inputs significantly influence biogeochemical processes and exchanges at the land-ocean interface, we know relatively little regarding predicting the impacts of land use, climate, and management strategies on watershed C fluxes. We propose to enhance and validate an existing regional earth system model, the Chesapeake Bay Forecasting System (CBFS) for predicting watershed C exports in the Chesapeake Bay region. The CBFS dynamically downscales global climate forecasts at time scales from sub-daily to interannual and decadal time-scales. It consists of regional atmosphere, ocean, biogeochemical and land dynamical models such as the Soil and Water Assessment Tool (SWAT) that are coupled together to provide comprehensive forecasts of the environmental behavior of the Chesapeake Bay region. Our primary objectives are to predict how exports of dissolved inorganic carbon (DIC), dissolved organic carbon (DOC), and particulate organic carbon (POC) in the Chesapeake Bay watershed will change in response to land use and climate, and to provide field monitoring and validation data to adequately evaluate model results. The proposal seeks to investigate the following questions: (1) How do patterns in forestation, agricultural productivity, urbanization, and climate variability influence regional C fluxes from coastal watersheds? (2) How will different land use and management scenarios influence watershed C fluxes to rivers and regional C budgets? (3) What is the composition and quality of C transported? We will carry out the following specific tasks to address the questions: (a) Apply and modify the existing CBFS model to predict effects of land use/land cover and climate on watershed DIC, DOC, and POC fluxes in over 50 routinely monitored subwatersheds of the Chesapeake Bay at the Smithsonian Environmental Research Center site, Baltimore Long-term Ecological Research site, and Maryland Non-tidal Core Trends Sampling Stations (b) Determine key environmental forcing variables and process level coefficients for CBFS and SWAT using a combination of LANDSAT imagery mapping, information on streamflow, precipitation, soils and C:N ratios, and statistical analyses of empirical data on C exports from existing long-term monitoring stations (c) Validate environmental parameters and verify watershed C export predictions based on existing data (d) Characterize bio-optical properties of DOC using fluorescence spectroscopy and UV absorbance for validation of model products and derivation of regional relationships and parameterizations for MODIS remote sensing applications. The major questions driving our research target NASA and USDA interests including (i) interactions between land management and land change and the C cycle and (ii) adaptation, mitigation, and vulnerability within the Earth system (land, ocean, and atmosphere). Our work will result in an enhanced version of the CBFS and SWAT that will be released to the user community. A metric of our success can be transferred to regional land and water resources managers, which have emerging needs for estimates in regional C budgets, developing strategies to reduce reactive DOC exports for protection of drinking water supplies, and predicting export of alkalinity influencing ecosystem processes and coastal ocean acidification.
2011 NASA Carbon Cycle & Ecosystems Joint Science Workshop Poster(s)
- Land Use and Climate Alter Carbon Dynamics in Watersheds of Chesapeake Bay
-- (Sujay S. Kaushal, Michael Pennino, Bala Mathukumalli, Shuiwang Duan, Melissa Grese, Kenneth Belt, Stuart Findlay, Peter Groffman, Raghu Murtugudde)
[abstract]
- Leaching and Decomposition of Leaves from Baltimore Urban Area - Implications for Urbaniation and Gloabl Warming on carbon cycle
-- (Shuiwang Duan, Sujay Kaushal)
[abstract]
More details may be found in the following project profile(s):
