no-bahar watershed is located, south of khorasan razavi province. geologically, the study area is a part of central iran zone. the rock units are late mesozoic and cenozoic in age in this watershed. no-babhar watershed includes several channels, which among them, only two main channels, motr-abad and solh-abad, have been studied. these rivers are mostly, braided channel in style, with high grad...

American Dippers concentrate on low-elevation streams during fall and winter in many parts of their range; however the breeding origin relative to the wintering location is poorly understood. Our objectives were to identify seasonal changes in the density and distribution of American Dippers, to classify the migratory behavior of the local population, and to determine the origin of winter migra...

The interaction between human activities and watershed geology is accelerating long-term changes in the carbon cycle of rivers. We evaluated changes in bicarbonate alkalinity, a product of chemical weathering, and tested for long-term trends at 97 sites in the eastern United States draining over 260,000 km(2). We observed statistically significant increasing trends in alkalinity at 62 of the 97...

Yersinia enterocolitica has been detected in surface water, and drinking untreated water is a risk factor for infection. PCR-based methods have been used to detect Y. enterocolitica in various sample types, but quantitative studies have not been conducted in water. In this study, quantitative PCR (qPCR)-based methods targeting the Yersinia virulence genes ail and yadA were used to survey the Gr...

Human activities pose a significant threat to the water quality of rivers when pollution exceeds the threshold limit. Urban activities in particular are highlighted as one of the major causes of contamination in surface water bodies in Asian countries. Evaluation of sustainable human population capacities in river watersheds is necessary to maintain better freshwater ecosystems in a country whi...

River ecosystems are influenced by processes operating and interacting on a variety of spatial scales. Quantifying the interplay of large and small-scale processes is central to both a basic ecological understanding of river ecosystems as well as the development of effective watershed management strategies. A key management goal for many western rivers restricted by large dams is to restore eco...

The authors developed a simple screening-level model of exposure of aquatic species to pyrethroid insecticides for the lower American River watershed (California, USA). The model incorporated both empirically derived washoff functions based on existing, small-scale precipitation simulations and empirical data on pyrethroid insecticide use and watershed properties for Sacramento County, Californ...

The investigation of geo hydrological features of drainage basin is necessary for planning and implementation of various watershed development programmes. The visual interpretation techniques coupled with morphometric analysis is used in the present study to evaluate the geomorphic process of upper watershed of river Subarnarekha in the state of Jharkhand, India. Various spatial information is ...

Morphometric analysis in a watershed is requirement analyzing hydrological conditions watershed, because the properties of river networks and their relationship to each other will affect condition water resources watershed. This study aims analyze variations discharge two rivers upper Bengkulu morphometric aspects that influence it. For this reason, several are calculated, such as area circulat...

Growing concerns over global environmental change, water resources, river restoration, and sustainable river management are focusing attention on the human dimension of fl uvial systems. This GSA Special Paper presents a set of studies and interpretations of river-channel change that refl ect modern viewpoints of river management in the twenty-fi rst century. It seeks to bridge a rich body of l...