Photo of Ge Sun

Ge Sun

Research Hydrologist
P.O. Box 12254
Research Triangle Park, NC 27709-2254
Phone: 919-549-4070
Fax: 919-513-2978
ge.sun@usda.gov

Current Research

Effects of climate change and land management on water quantity and quality; Application of computer simulation models, GIS, and remote sensing in quantifying water balances at multiple temporal and spatial scales. Impacts of global change on water supply and demand. Forestry Best Management Practices in affecting and soil erosion and sedimenttransport in watersheds. Hydrology of forested wetland ecosystems under environmenal change; Impact of wildland fire on watershed hydrology. 

Current Projects:
  1. Measuring and modeling carbon and water flux dynamics and processes across a climatic and management gradients in the eastern U.S. and China
  2. Modeling the potential effects of climate change, landuse change, and population growth on water supply and demand in the continental U.S.
  3. Evaluating the effectiveness of forest buffers on water quality and flow generations in the Piedmont region of North Carolina
  4. Wildfire and Fuel Treatment Strategy Effects on Water Quantity across the Conterminous United States

Education

Ph.D. in Forest Hydrology and Watershed Management, 1995
University of Florida
M.S. in Forest Hydrology, 1988
Beijing Forestry University
B.S. in Soil and Water Conservation, 1985
Beijing Forestry University

Awards and Recognition

Research & Development Deputy Chief Award's Distingushed Science Award, 2017
Sustained productivity and leadership in forest hydrology research
Chief's Honor Award, 2017
Applying Knowledge Globally; Forests and Water in a Changing Environment
Southern Research Station Director's Distinguished Science Award, 2016
Certificate of Appreciation, 2016
An author of "Understanding the Impacts of Drought on the Nation's Forest and Grasslands: Providing a Scientific Foundation for Effective Management Responses", which Received a 2016 Chief's Award for the Category of Sustaining Forests and Grasslands
Fellow of American Water Resources Association, 2015
USFS Southern Research Station Director's Global Stewardship Award, 2009

Featured Publications and Products

Publications

Research Highlights

Burning forests can impact water supplies (2017)
SRS-2017-145 The number of wildland fires and burned areas in the U.S. is on the rise as a result of a warming climate, drought, and increasing human ignitions. Although forests and rangelands provide more than half of U.S. water supplies, the long-term impacts of both wildland and prescribed fire on water supplies have not been previously measured nor factored into water management strategies. Forest Service researchers developed a practical framework to evaluate fire impacts on water resources by synthesizing 30-year-old records of wildland fire, climate, and river flow for 162 locations across the U.S.

Climate Change Impacts on Ecosystem Services: water, carbon, and biodiversity (2010)
SRS-2010-015 SRS is enhancing one of its models that examines the potential impacts of climate change, land use, and population changes on water supplies. The researchers are building this integrated, water-centered modeling on previous water supply and demand research that resulted in a Water Supply Stress Index (WaSSI) model.

Fertilized Pines Use Water More Efficiently But May Suffer Worse in Droughts (2015)
SRS-2015-235 Fertilized loblolly pine trees produce more wood than their unfertilized counterparts, even when less water was available, butthis may also indicate that fertilized pine plantations are more vulnerable to severe drought.

High Forest Productivity Often Comes at the Expense of Soil Carbon Storage (2015)
SRS-2015-250 Forest Service scientists and their research partners are studying the role of managed forests in regional carbon, water, and energy exchange to understand how managed forests contribute to land-atmosphere feedbacks and climate dynamics.

Impacts of wildland fires on U.S. freshwater resources are variable (2018)
SRS-2018-61 Burning forests alters watershed hydrological cycles by modifying soil and forest cover properties. Researchers found that fires with moderate or high burn severity contributed most to increased river flows, while prescribed fires had little effect on water yield for large basins. Climate variability, including drought, may mask the effects of wildland fire on water supplies, so effective forest management practices must consider local watershed conditions.

International collaborators develop easy-to-use formulas for water and carbon accounting (2017)
SRS-2017-148 Ecosystem water use is closely coupled with ecosystem productivity, water availability, and water supplies, but accurate water use accounting remains challenging because of model deficiencies or difficulty of model use in practice. Forest Service researchers combined global water use or evapotranspiration measurements with remote sensing products to create a series of simple formulas that can accurately estimate water use and thus water and carbon budgets for seven different land cover types. This work improves understanding of the connections between forest management practices, carbon and water cycles, and changing climate conditions.

Southern forested wetlands are projected to become drier in the future (2018)
SRS-2018-56 Extensive southern forested wetlands provide important ecosystem services. A study of five typical forested wetlands across the Southeast suggests that these wetlands will likely become drier or may even disappear by the end of this century under severe climate change scenarios. This information can help land managers develop climate change mitigation and adaptation methods to protect these important natural resources.

Tools to help international conservation agencies make sound decisions (2011)
SRS-2011-02 Researchers with the Eastern Forest Environmental Threat Assessment Center (EFETAC) applied models they developed with partners to measure water supply stress in relation to carbon and biodiversity and to evaluate ecosystem services to several locations in Africa-Nyungwe National Park, Rwanda; Ruaha River Watershed, Tanzania; and Luangwa Valley, Zambia-to look at the potential impact of land use practices on water quality and quantity. These tools can be used by conservation agencies in any location worldwide to make sound decisions. This research is also important because the African ecosystems where these models are being applied are ecosystems that could potentially develop in the United States in the future due to the impacts of climate change.

R&D Affiliations
Research Topics
External Resources