various human pressures are affecting the aquatic biocoenosis in running waters of iran - similar to many other areas of the world. overall 190 sites, 88 at salmonid (44 reference/impacted respectively) and 102 at cyprinid (50 reference/52 impacted) streams of the southern caspian sea basin were investigated in terms of human pressures present and the related impact on fish assemblages. in tota...

Species trait data have been used to predict and infer ecological processes and the responses of biological communities to environmental changes. It has also been suggested that, in lieu of trait, data niche differences can be inferred from phylogenetic distance. It remains unclear how variation in trait data may influence the strength and character of ecological inference. Using species-level ...

There is great need to identify simple yet reliable indicators of fishing effects within the multi-species, multi-gear, data-poor fisheries of the Caribbean. Here, we investigate links between fishing pressure and three simple fish metrics, i.e. average fish weight (an estimate of average individual fish size), fish density and fish biomass, derived from (1) the parrotfish family, a ubiquitous ...

Thalweg profiles are longitudinal profiles of the streambed elevation measured along the deepest portion of the stream. This technique has recently been advocated as a tool to monitor fish habitat in streams because profiles can provide useful information on such habitat, and measurements are both repeatable and independent of stream flow. However, a relation between fish abundance and metrics ...

A two-dimensional hydraulic model River2D was used to investigate the significance of flow complexity on habitat preferences of brook trout Salvelinus fontinalis) in the high-gradient Staunton River in Shenandoah National Park, Virginia. Two 100-m reaches were modeled where detailed brook trout surveys 10–30-m resolution have been conducted annually since 1997. Spatial hydraulic complexity metr...

We used local and landscape models to predict fish assemblages in the Great Swamp, NY, a region undergoing rapid development. Fish were surveyed across 17 sites. Fish-species richness, diversity, percent intolerant species, and IBI metrics for fish species richness, benthic insectivores, terete minnows, and dominant species were calculated. Local stream features were characterized and surroundi...

in this paper, we study a class of finsler metrics which contains the class of p-reducible andgeneral relatively isotropic landsberg metrics, as special cases. we prove that on a compact finsler manifold,this class of metrics is nothing other than randers metrics. finally, we study this class of finsler metrics withscalar flag curvature and find a condition under which these metrics reduce to r...

Ecological monitoring programs are often designed to provide information on the status and/or trends of populations, communities, and ecosystems that are of interest to natural resource managers. The information these programs provide is then used by managers to make management decisions (i.e. increase or decrease extraction levels, allow or restrict access), and at the same time can be used to...

A 4.1 million m(3) coal ash release into the Emory and Clinch rivers in December 2008 at the Tennessee Valley Authority's Kingston Fossil Plant in east Tennessee, USA, prompted a long-term, large-scale biological monitoring effort to determine if there are chronic effects of this spill on resident biota. Because of the magnitude of the ash spill and the potential for exposure to coal ash-associ...