Watershed transform has been widely used in medical image segmentation. One fundamental problem with it is over-segmentation. There are mainly two approaches to deal with this problem: hierarchical segmentation and segmentation with markers. The markers, either automatically extractedor interactively generated, aremostlyused in thehomotopymodification of morphological gradients prior to the wat...

A Geographic Information System (GIS)–based, lumped parameter water quality model was developed to estimate the spatial and temporal nitrogen–loading patterns for lower coastal plain watersheds in eastern North Carolina. The model uses a spatially distributed delivery ratio (DR) parameter to account for nitrogen retention or loss along a drainage network. Delivery ratios are calculated from tim...

Determining the relative contributions of nitrate contamination in agricultural watersheds characterized by applications of both mineral and animal waste nitrogen to fields is important in evaluating the environmental consequences of these practices. Here, the use of nitrate–nitrogen (NO3−–N) stable isotopes to identify contaminant sources was examined in surface waters of an agricultural water...

We constructed watershed mass-balance budgets of carbon (C) and nitrogen (N) and measured seasonal net N mineralization in an attempt to account for nearly 40 years of large discrepancies in stream NO,-N export in two adjacent, gauged watersheds at the U.S. Department of Agriculture Forest Service's Fernow Experimental Forest, WV. These watersheds have similar management histories, varying prim...

Based on the Representative Elementary Watershed (REW) approach, the modelling tool REWASH (Representative Elementary WAterShed Hydrology) has been developed and applied to the Geer river basin. REWASH is deterministic, semi-distributed, physically based and can be directly applied to the watershed scale. In applying REWASH, the river basin is divided into a number of sub-watersheds, so called ...

0022-1694/$ see front matter 2012 Elsevier B.V. A doi:10.1016/j.jhydrol.2012.01.035 ⇑ Corresponding author. Tel.: +1 706 202 8193. E-mail addresses: [email protected] (H. Ssegane), Tollner), [email protected] (Y.M. Mo (T.C. Rasmussen), [email protected] (J.F. Dowd). Hydrological flow predictions in ungauged and sparsely gauged watersheds use regionalization or classification of hydrologi...

Caffeine has been suggested as a chemical indicator for domestic wastewater in freshwater systems, although it is not included in water quality monitoring programs. The Third Fork Creek watershed in Durham, NC, is highly urbanized, with a history of receiving untreated wastewater from leaking and overflowing sanitary sewers. The poor water quality originating in the Third Fork Creek watershed t...

A general framework of spatio-spectral segmentation for multispectral images is introduced in this paper. The method is based on classification-driven stochastic watershed by Monte Carlo simulations, and it gives more regular and reliable contours than standard watershed. The present approach is decomposed into several sequential steps. First, a dimensionality reduction stage is performed using...

Watershed educational and informational efforts have largely neglected to inform one important group of decision-makers: local government officials. The Internet Watershed Educational Tool (InterWET) was developed to help inform local officials about water resources, using as a case study the Spring Creek Watershed in central Pennsylvania. Utilizing the “microworlds” concept, InterWET consists ...

We study the watersheds in edge-weighted graphs. Contrarily to previous works, we define the watersheds following the intuitive idea of drops of water flowing on a topographic surface. We establish the consistency (with respect to characterizations of the catchment basins and dividing lines) of these watersheds, prove their optimality (in terms of minimum spanning forests) and derive a linear-t...