The spatial variability of soil organic carbon (SOC) and total nitrogen (STN) levels is important in both global carbon-nitrogen cycle and climate change research. There has been little research on the spatial distribution of SOC and STN at the watershed scale based on geographic information systems (GIS) and geostatistics. Ninety-seven soil samples taken at depths of 0-20 cm were collected dur...

Quantification of the changes of water balance components is significant for water resource assessment and management. This paper employed the Soil and Water Assessment Tool (SWAT) model to estimate the water balance in a mountainous watershed in northwest China at different spatial scales over the past half century. The results showed that both Nash-Sutcliffe efficiency (NSE) and determination...

A common theme in recent landscape studies is the comparison of riparian and watershed land use as predictors of stream health. The objective of this study was to compare the performance of reach-scale habitat and remotely assessed watershed-scale habitat as predictors of stream health over varying spatial extents. Stream health was measured with scores on a fish index of biotic integrity (IBI)...

BACKGROUND AND PURPOSE Watershed ischemia is a significant cause of stroke in severe carotid disease, but its pathophysiology is unsettled. Although hemodynamic compromise has long been regarded as the main mechanism-particularly with deep watershed infarction-there is some contradictory evidence from clinical and pathological studies for a role of microembolism, thought to result from plaque i...

Non-point source pollution is well recognized as one of the most critical environmental hazards of modern times. In Illinois, non-point source pollution is the major cause of water quality problems, and soil erosion from agricultural lands is the major source of such pollution. Accelerated by anthropogenic activities, soil erosion reduces crop productivity and leads to subsequent problems from ...

The deposition of dust has recently increased significantly over some regions of the western US. Here we explore how changes in dust deposition have affected the biogeochemistry of two alpine watersheds in Colorado, US. We first reconstruct recent changes in the mass accumulation rate of sediments and then we use isotopic measurements in conjunction with a Bayesian mixing model to infer that ap...

The ecohydrologic effects of urbanization that is dominated by forests clearing are not well understood in the southeastern United States. We utilized long-term monitoring data to quantify the annual water balance, stormflow characteristics, and seasonal flow patterns of an urbanized watershed (UR) (0Ð70 km2) and compared it to a fully forested watershed (FOR) (2Ð95 km2) in central North Caroli...

Watershed transform has interesting properties that make it useful for much different image segmentation analysis, it has important drawbacks (Over segmentation, sensitivity to noise, poor detection of thin or low signal to noise ratio structures). Recent advances in medical imaging technology using multiple Computed tomographies (CT) provide volumetric datasets with spatial resolution segmenta...

In this paper we present a new implementation of a rainfalling watershed segmentation algorithm. Our previous algorithm was a one-run algorithm. All the steps needed to compute a complete watershed segmentation were done in one run over the input data. In our new algorithm we tried another approach. We separated the watershed algorithm in several low-complexity relabeling steps that can be perf...

Medical Image segmentation deals with segmentation of tumor in CT and MR images for improved quality in medical diagnosis. Geometric Vector Flow (GVF) enhances the concave object extraction capability. However, it suffers from high computational requirement and sensitiveness to noise. This paper intends to combine watershed algorithm with GVF snake model to reduce the computational complexity, ...