Effects of Nutrients on Spring Ecosystems

The relationship between nutrients and spring ecosystem structure and function primarily focuses on the state-wide increase in spring nitrate concentrations derived from anthropogenic sources and the concurrent observed visual decline of these ecosystems. However, the apparent correlation between increased nitrate loading and declining aesthetic appearance of spring ecosystems has only anecdotally provided evidence for a causative relationship. Organism-level studies, focused on single species of algae, vascular plants, aquatic macroinvertebrates, and primary and secondary consumers, have produced mixed results that do not currently present a clear or consistent link between nutrient availability and population structure in springs. Firm conclusions linking rising spring nitrogen concentrations and changes to individual components of biotic communities remain illusive, in some measure due to the immense complexity of spring ecosystems and the large number of external forcing functions (energy and matter inputs) that shape their structure and functions.