Background/Question/Methods

In this study, we examined interactive effects of nutrient availability, river flow and food web structure on algal growth and species composition in the Middle Rio Grande, New Mexico. Algal community dynamics can be affected by both bottom-up and top-down factors. Algal production may be limited by low levels of nutrients or low light availability. Conversely, production is expected to increase when nutrient levels are high and light availability is not limited. Top-down factors such as grazing by invertebrates can also alter periphyton growth and community composition. Generally, a reduction in grazers results in periphyton biomass increases and shifts in growth forms (to more upright... |