Although the importance of long-term data has been emphasized by ecologists in recent years, little is known about how communities may change over time. In this study, we describe the general patterns of aquatic macrophyte diversity in the Paraná River floodplain observed during six years of study. Temporal changes in community composition were also evaluated. Data on the presence or absence of...

The debate on scale use in river management focuses primarily on the (lack of) fit between the bio-geophysical and institutional systems. However, in this article we focus on the 'subjective' aspect of scale preferences in water governance. We apply an adapted version of the Integrated Scale Hierarchy for Rivers to determine the degree of fit between the scale preferences of the actors involved...

Habitat evaluation of wadeable streams based on accepted protocols provides a rapid and widely used adjunct to biological assessment. However, little effort has been devoted to habitat evaluation in non-wadeable rivers, where it is likely that protocols will differ and field logistics will be more challenging. We developed and tested a non-wadeable habitat index (NWHI) for rivers of Michigan, w...

The review by Nguyen et al. [1] acknowledges the substantially lower baseline central venous oxygen saturation (ScvO2) values reported by Rivers et al. [2] (48.6 ± 11.2 %) when compared to those for ProCESS [3] (71 ± 13 %), ARISE [4] (72.7 ± 10.5 %) and ProMISe [5] (64 ± 20 %) trials. Assuming normality, the distribution of baseline ScvO2 values in the study by Rivers et al. differed from those...

 The concentrations of Cd, Pb, Ni and Hg were determined in gill, liver and muscle of Barbus xanthopterus in down streams of Karoon and Dez Rivers during summer 2009. Heavy metal concentrations varied significantly, depending on the types of the tissue in fish species. The levels of heavy metals such as Cd, Pb, Ni and Hg in the Barbus xanthopterus of Karoon River were higher than in Barbus xant...

A critical decision in species conservation is whether to target individual species or a complex of ecologically similar species. Management of multispecies complexes is likely to be most effective when species share similar distributions, threats, and response to threats. We used niche overlap analysis to assess ecological similarity of 3 sensitive desert fish species currently managed as an e...

This paper presents a simple method to predict flow diversion by vertical angled screens in open channels. The performance of this method has been compared with the experimental results from a recent laboratory study of vertical angled screens. This method is then used to predict the effect of screen porosity, variation of porosity along the length of the screen, and several other factors on th...