Long-Term Ecohydrologic Monitoring: A Case Study from the Santee Experimental Forest, South Carolina

Long-term research on gauged watersheds within the USDA Forest Service’s Experimental Forest and Range (EFR) network has contributed substantially to our understanding of relationships among forests, water, and hydrologic processes and watershed management, yet there is only limited information from coastal forests. This article summarizes key findings from hydrology and water-quality studies based on long-term monitoring on first-, second-, and third-order watersheds on the Santee Experimental Forest, which are a part of the headwaters of the east branch of the Cooper River that drains into the harbor of Charleston, South Carolina. The watersheds are representative forest ecosystems that are characteristic of the low-gradient Atlantic Coastal Plain. The long-term (35-year) water balance shows an average annual runoff of 22% of the precipitation and an estimated 75% for the evapotranspiration (ET), leaving the balance to groundwater. Non-growing season prescribed fire, an operational management practice, shows no effects on streamflow and nutrient export. The long-term records were fundamental to understanding the effects of Hurricane Hugo in 1989 on the water balance of the paired watersheds that were related to vegetation damage by Hugo and post-Hugo responses of vegetation. The long-term precipitation records showed that the frequency of large rainfall events has increased over the last two decades. Although there was an increase in air temperature, there was no effect of that increase on annual streamflow and water table depths. The long-term watershed records provide information needed to improve design, planning, and assessment methods and tools used for addressing the potential impacts of hydrologic responses on extreme events; risk and vulnerability assessments of land use; and climate and forest disturbance on hydrology, ecology, biogeochemistry, and water supply

Downward Longwave Radiation Retrieved from MODIS Imagery and Possible Application on Water Resource Management at Turkey Creek Watershed in South Carolina

2010 S.C. Water Resources Conferences - Science and Policy Challenges for a Sustainable Futur

Comparison of Potential Evapotranspiration (PET) using Three Methods for a Grass Reference and a Natural Forest in Coastal Plain of South Carolina

2014 S.C. Water Resources Conference - Informing Strategic Water Planning to Address Natural Resource, Community and Economic Challenge

Modeling the Effect of Land Use Change on Hydrology of a Forested Watershed in Coastal South Carolina

2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Regio

Case Study Hydrologic Effects of Size and Location of Fields Converted from Drained Pine Forest to Agricultural Cropland

Abstract: Hydrological effects of land-use change are of great concern to ecohydrologists and watershed managers, especially in the Atlantic coastal plain of the southeastern United States. The concern is attributable to rapid population growth and the resulting pressure to develop forested lands. Many researchers have studied these effects in various scales, with varying results. An extended watershed-scale forest hydrologic model, calibrated with 1996–2000 data, was used to evaluate long-term hydrologic effects of conversion to agriculture (corn–wheat–soybean cropland) of a 29.5-km2 intensively managed pine-forested watershed in Washington County in eastern North Carolina. Fifty years of weather data (1951–2000) from a nearby weather station were used for simulating hydrology to evaluate effects on outflows, evapotranspiration, and water table depth compared with the baseline scenario. Other simulation scenarios were created for each of five different percentages (10, 25, 50, 75, and 100%) of land-use conversion occurring at upstream and downstream locations in the pine-forest watershed. Simulations revealed that increased mean annual outflow was significant (α 0.05) only for 100 % conversion from forest (261 mm) to agricultural crop (326 mm), primarily attributed to a reduction in evapotranspiration. Although high flow rates>5 mm day−1 increased from 2.3 to 2.6 % (downstream) and 2.6 to 4.2 % (upstream) for 25 to 50 % conversion, the frequency was higher for the upstream location than the downstream. These results were attributed to a substantial decrease in soil hydraulic conductivity of one of the dominant soils in the upstream location, which is expected after land-use conversion to agriculture. As a result, predicted subsurface drainage decreased, and surface runoff increased as soil hydraulic conductivity decreased for the soil upstream. These results indicate tha

Hydrologic Processes of Forested Headwater Watersheds Across a Physiographic Gradient in the Southeastern United States

2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Regio

STREAMFLOW CHARACTERISTICS OF A NATURALLY DRAINED FORESTED WATERSHED IN SOUTHEAST ATLANTIC COASTAL PLAIN

ABSTRACT Information about streamflow characteristics e.g. runoff-rainfall (R/O) ratio, rate and timing of flow, surface and subsurface drainage (SSD), and response time to rainfall events is necessary to accurately simulate fluxes and for designing best management practices (BMPs). Unfortunately, those data are scarce in the southeastern Atlantic coastal plain, a highly urbanizing region characterized by poorly drained lowgradient forested landscape where runoff is dominated by shallow SSD and saturation excess overland flow. In this paper we evaluate these characteristics using four years (2005-08) of streamflow data measured on a 72 km 2 naturally drained forested watershed on the Francis Marion National Forest in coastal South Carolina. The calculated average event peak flow rate, time to peak, event duration, SSD as % of streamflow, and R/O ratio were 4.2 m 3 sec-1 km-2, 14.6 hrs, 13.9 days, 29%, and 20%, respectively, for 12 events with rainfall amount varying from 153 mm to 34 mm. The events were similar to those from the historic data (1964-73) indicating a hydrologic recovery of forest since its regeneration after Hurricane Hugo in 1989. The average drainage response time to the rain was 7.8 hours. Results suggested that the runoff and peak flow rate of storm event

Forest evapotranspiration: measurement and modelling at multiple scales

Forest evapotranspiration: measurement and modelling at multiple scale