Knowing about the ecological aspects involved in commercial breeding of aquatic organisms becomes an important tool to make aquaculture more productive and less impactful. Thus, periphyton taxon composition biomass on different substrates influence these water quality growth parameters Nile tilapia fingerlings were examined. An experiment with three treatments (substrates for periphyton: geomem...

Temperature is a primary physical and biogeochemical variable in aquatic systems. Field-based measurement of temperature at discrete sampling points has revealed temperature variability in fluvial systems, but traditional techniques do not readily allow for synoptic sampling schemes that can address temperature-related questions with broad, yet detailed, coverage. We present results of thermal ...

Canal wall brushing, accomplished by a tractor-mounted custom-designed rotating metal brush, was an effective means of removing nuisance periphytic cyanobacterial growth and consequently reducing MIB and geosmin production in the Arizona Canal, a major water conveying open channel in the metropolitan Phoenix (Arizona) water supply system. On average, c. 80% of the periphyton biomass was removed...

Gradients in photosynthesis (P) and respiration (R) were measured on an unperturbed portion of the Rio Mameyes, a tropical stream in the Luquillo Experimental Forest, northeastern Puerto Rico. Rates of P, which were similar to those of streams in temperate-deciduous forests, were low in the heavily canopied headwaters (<70 g>O2 m−2 y−1) and were higher (453–634 g O2 m−2 y−1) in middle and lower...

The effects of global and local environmental changes are transmitted through networks of interacting organisms to shape the structure of communities and the dynamics of ecosystems. We tested the impact of elevated temperature on the top-down and bottom-up forces structuring experimental freshwater pond food webs in western Canada over 16 months. Experimental warming was crossed with treatments...

The ability of small-scale experiments to predict dynamics and patterns observed at larger scales is an important issue in ecology. In this paper, we describe responses of benthic, trout stream communities to replicated, whole-ecosystem perturbations resulting from pathogen-induced reductions in populations of a dominant grazer, the caddisfly Glossosoma nigrior. Previous small-scale experiments...