the closed nature of geochemical data has been proven in many studies. compositional data have special properties that mean that standard statistical methods cannot be used to analyse them. these data imply a particular geometry called aitchison geometry in the simplex space. for analysis, the dataset must first be opened by the various transformations provided. one of the most popular of the a...

Fine inorganic sediment (≤ 2mm) is a major non-point source pollutant in streams. While some fine sediment in streams is natural, loads in human-impacted streams often exceed their capacity to flush these sediments during high flows. Regardless of the source, the negative effects of increased levels of fine sediment in streams are realized in all biotic components of stream ecosystems from micr...

Stream channel erosion has long been suspected as the major contributor to long-term sediment yield from urbanizing watersheds. For San Diego Creek in southern California, measurements from 1983 to 1993 showed that stream channel erosion furnished 10(5) megagrams per year of sediment, or about two-thirds of the total sediment yield. Thus, because channel erosion can be a major source of sedimen...

uncertainty associated with mixing models is often substantial, but has not yet been fully incorporated in models. the objective of this study is to develop and apply a bayesian-mixing model that estimates probability distributions of source contributions to a mixture associated with multiple sources for assessing the uncertainty estimation in sediment fingerprinting in zidasht catchment, iran....

Forestry best management practices (BMPs) are used to reduce sedimentation from forest stream crossings. Three BMP treatments (BMP ́, BMP-std, and BMP+) were applied to three forest road stream crossings (bridge, culvert, and ford). BMP ́ did not meet existing BMP guidelines, BMP-std met standard recommendations, and BMP+ treatments exceeded recommendations. Following BMP applications, three simu...

In this paper, development of a semi-two- dimensional mathematical model called SDAR is introduced. The model is composed of two principal modules of hydraulics and sediment transport. The newly developed SDAR model has a number of capabilities including determination of sediment transport rate, aggradation - degradation&#10calculation, longitudinal profile and lateral cross–sectional variation...

We determined the extent that a riparian buffer reduces stream suspended sediment concentrations by filtering road runoff during 18 rain events in a 2.5-ha, multi-use watershed in northern Thailand. The dominant buffer species was the perennial sedge Fimbristylis aphylla Zoll. ex Steud. (Cyperaceae). We monitored stream sediment concentration for situations where road runoff either flowed into ...

Documenting the effects of agricultural land retirement on stream-sediment sources is critical to identifying management practices that improve water quality and aquatic habitat. Particularly difficult to quantify are the effects from conservation easements that commonly are discontinuous along channelized streams and ditches throughout the agricultural midwestern United States. Our hypotheses ...

In this paper, development of a semi-two- dimensional mathematical model called SDAR is introduced. The model is composed of two principal modules of hydraulics and sediment transport. The newly developed SDAR model has a number of capabilities including determination of sediment transport rate, aggradation - degradation calculation, longitudinal profile and lateral cross–sectional variation s...