Microbial activity associated with seston in headwater streams: effects of nitrogen, phosphorus and temperature

SUMMARY 1. The influences of temperature and dissolved nitrates and phosphates on microbial activity associated with suspended fine particulate organic matter (seston) were evaluated in four headwater streams in the southern Appalachian Mountains. 2. Temperature manipulations of ± 5°C always induced significant changes in [14C] glucose mineralization (ANOVA; P0.05) in short‐term (i.e. 3 h) experiments. 4. Microorganisms attached to refractory particulate organic matter do not appear to be limited by nitrogen or phosphorus even in streams with ambient nutrient concentrations as low as 0.06 mg NO3 I−1 and