Journal
ENVIRONMENTAL MONITORING AND ASSESSMENT
Volume 174, Issue 1-4, Pages 361-388Publisher
SPRINGER
DOI: 10.1007/s10661-010-1463-y
Keywords
Nutrients; Natural background concentrations; Eutrophication assessments; Rivers; Coastal water; North Sea
Categories
Ask authors/readers for more resources
Natural background concentrations of nutrients are needed for the assessments of eutrophication processes and their status. Natural background concentrations of total nitrogen (TN) and total phosphorus (TP) were modelled for the rivers discharging into the German Bight and the Rhine considering individual catchment sizes, freshwater flows and soil types. These data were validated by comparison with data from unpolluted rivers. The consistency of modelled and some compiled nutrient concentrations was confirmed by their area-specific load dependency on freshwater discharges. Pristine inorganic nutrient concentrations were deduced from modelled relations to TN and TP in unpolluted rivers. Pristine nutrient gradients between rivers and offshore waters were estimated by linear mixing until a salinity of 32, continued by hyperbolic fits towards recent mean offshore values (salinity 34.5-35). Based on these gradients and recent mean salinities, maps of pristine surface gradients were plotted for the whole German Bight. Variability was transferred from recent conditions as percentage of standard deviation. Reported historical nutrient data and concentrations from unpolluted rivers, coastal and offshore North Sea waters are discussed concerning their relations to natural background conditions.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available