Carbon-to-chlorophyll ratio for phytoplankton in temperate coastal waters: Seasonal patterns and relationship to nutrients
Jakobsen, H.H.; Markager, S. (2016). Carbon-to-chlorophyll ratio for phytoplankton in temperate coastal waters: Seasonal patterns and relationship to nutrients. Limnol. Oceanogr. 61(5): 1853-1868. https://dx.doi.org/10.1002/lno.10338
In: Limnology and Oceanography. American Society of Limnology and Oceanography: Waco, Tex., etc. ISSN 0024-3590; e-ISSN 1939-5590, meer
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Abstract |
Carbon-to-chlorophyll a ratios (C:Chl a; weight : weight) were analyzed for 7578 coastal seawater samples collected from Danish waters from 1990 to 2014. The aim was to identify the seasonal and spatial dynamics relative to nutrient richness and to study the effect of reduced nitrogen loadings over time. C:Chl a values were lowest during winter, about 15 across all stations. During the spring, C:Chl a increased to summer values between 20 and 96, depending on the annual mean of total nitrogen concentration. An inter-annual sinusoidal model with monthly time steps described the seasonal C:Chl a pattern well. The amplitudes of the model varied inversely with the annual mean of total nitrogen. Data also showed that a reduction in nitrogen loadings to the area by ~40% over the past 24 yr, resulted in a statistically significant increase in mean annual C:Chl a values of 0.8 ± 0.2 yr-1. The patterns derived from this large data set can be used to predict C:Chl a values for temperate coastal phytoplankton. Use of the empirical relationships derived from the data set improves predictions of C:Chl a values and thereby, e.g., carbon based food-web calculations and carbon-based ecosystem models, which often are validated using chlorophyll measurements. |
Dataset |
- Danish Centre for Environment and Energy (2019). Phytoplankton data for Danish marine monitoring (ODAM) from 1988 - 2016, meer
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