Nepal’s terrain is dissected by many rivers and streams to form a complex of watersheds. Natural and human-induced processes operate on these watersheds. The main processes that lead to the degradation of watersheds are landslides, soil erosion, floods, biodiversity loss, and unsustainable water extraction and farming practices. These lead to the loss of soil fertility, the depletion of water t...

We study hierachical segmentation in the framework of edgeweighted graphs. We define ultrametric watersheds as topological watersheds null on the minima. We prove that there exists a bijection between the set of ultrametric watersheds and the set of hierarchical edgesegmentations.

N-propylsalicylidene based on silica as ion exchanger (IE) was used for the separation by complexation of Mn2+, Co2+, Ni2+, Cu2+, Hg2+, Cr3+, Fe3+, and UO22+ from their parent solutions. IE and its metal complexes are characterized by elemental analysis, electronic and infrared spectra, in addition to thermal analysis in atmospheric pressure. The mode of chelation and the proposed geometric str...

Urban water systems are impacted by land use within their source watersheds, as it affects raw water quality and thus the costs of water treatment. However, global estimates of the effect of land cover change on urban water-treatment costs have been hampered by a lack of global information on urban source watersheds. Here, we use a unique map of the urban source watersheds for 309 large cities ...

On-site wastewater treatment systems (OWTSs) are widely used in the Southeastern United States for municipal wastewater treatment. As urban and suburban populations increase, the use of OWTSs is expected to further increase. This region heavily depends on surface waters for its water supply, therefore, the impact of OWTSs on surface water quality and quantity must be investigated. Conventional ...

0022-1694/$ see front matter Published by Elsevier doi:10.1016/j.jhydrol.2010.05.045 * Corresponding author. Tel.: +1 303 236 4882x313 E-mail address: [email protected] (A.J. Ranalli). We reviewed published studies from primarily glaciated regions in the United States, Canada, and Europe of the (1) transport of nitrate from terrestrial ecosystems to aquatic ecosystems, (2) attenuation of nitrat...

Agricultural non-point source (NPS) pollution poses a severe threat to water quality and aquatic ecosystems. In response, tremendous efforts have been directed toward reducing these pollution inputs by implementing agricultural conservation practices. Although conservation practices reduce pollution inputs from individual fields, scaling pollution control benefits up to the watershed level (i.e...

Chloride is a relatively unreactive plant nutrient that has long been used as a biogeochemical tracer but also can be a pollutant causing aquatic biology impacts when concentrations are high, typically from rock salt applications used for deicing roads. Chloride inputs to watersheds are most often from atmospheric deposition, road salt, or agricultural fertilizer, although studies on agricultur...

The Terrain Resources Inventory Mapping (TRIM) data standard in BC, Canada, includes speci cations for river data and elevation data that are typically met by interpretation of stereo orthophotos. It does not specify that breaklines for watersheds be interpreted from the photos, thus we must extract them from the data. We seek a system of watersheds that, while not exact due to errors in the da...

When improperly managed, land application of animal manures can harm the environment; however, limited watershed-scale runoff water quality data are available to research and address this issue. The water quality impacts of conversion to poultry litter fertilization on cultivated and pasture watersheds in the Texas Blackland Prairie were evaluated in this three-year study. Edge-of-field N and P...