Water samples for nutrient analysis were immediately
filtered through Whatman GF/F filters using a 50-ml syringe and
stored on dry ice in 20-ml HDPE scintillation vials or 50-ml centrifuge tubes. All nutrient analyses, except for NH4and urea–N, wereperformed on a Bran and Luebbe AutoAnalyzer II. NO3,NO2 and soluble reactive phosphorus (SRP) were analyzed using