Soil moisture supply and atmospheric demand for water independently limit—and profoundly a ect—vegetation productivity and water use during periods of hydrologic stress1–4. Disentangling the impact of these two drivers on ecosystem carbon and water cycling is di cult because they are often correlated, and experimental tools for manipulating atmospheric demand in the field are lacking. Consequen...

1.1 Statement of problem Estimation of soil moisture using microwave remote sensors holds great promise for many applications, including numerical weather prediction and agriculture. However, a scale disparity exists between the resolutions of future satellite-borne microwave remote sensor data (30-60 km) and the much finer scales at which soil moisture estimates are desired (~ 1 km). Hydrology...

In the effort to determine if hydrologic restoration in Knuthsen Meadow affects root abundance and soil moisture, we gathered preliminary data to determine the optimal experimental design and sample size necessary to detect a 25% increase in root biomass and soil moisture following restoration. We found high variability in root biomass, with upstream meadow reaches having substantially greater ...

Spaceborne scatterometers and radiometers offer soil moisture information with resolutions in the order of a few tens of kilometres. However, hydrologic users often request a resolution in the order of 1 km. Based on the insight that surface soil moisture in part is driven by large scale atmospheric forcing, a temporal analysis was carried out between backscatter on a local (1 km) and a regiona...

Predicting the hydrologic consequences of biomass cropping systems requires an understanding of how different crops and management practices affect soil hydraulic properties across space and time. To inform such predictions, I investigated the impacts of five biomass cropping systems on the hydraulic properties of soils across a landscape gradient in wet, dry, and average rainfall years. I used...

Agricultural drought is defined as a shortage of moisture in the root zone of plants. Recently available satellite-based remote sensing data have accelerated development of drought early warning system by providing continuous soil moisture information in space and time. Nonetheless, the shallow sensing depth (top few cm) and uncertain accuracy of currentlyavailable satellite soil moisture retri...

Organic and inorganic carbon (C) fluxes transported by water were evaluated for dominant hydrologic flowpaths on two adjacent headwater catchments in the Brazilian Amazon with distinct soils and hydrologic responses from September 2003 through April 2005. The Ultisoldominated catchment produced 30% greater volume of storm-related quickflow (overland flow and shallow subsurface flow) compared to...

Estimating surface runoff for ungauged watershed is an important issue. The Soil Conservation Service Curve Number (SCS-CN) method developed from long-term experimental data is widely used to estimate surface runoff from gaged or ungauged watersheds. Many modelers have used the documented SCS-CN parameters without calibration, sometimes resulting in significant errors in estimating surface runo...