Before revision:  Unlike the constant environment case , diversity depends on the concentration of nutrients supplied to the community. These changes in diversity are driven by an "early-bird" effect in which species specialized for nutrients that are initially more abundant gain a population advantage over other species.
After revision:  Unlike the constant environment case , diversity depends on the amount of nutrient supplied due to an "early-bird" effect in which species specialized for nutrients that are initially more abundant gain a population advantage over other species.