Reply to Howarth and Paerl: Is control of both nitrogen and phosphorus necessary?

As we stated in our paper (1), extrapolation of our results to estuaries should be done with caution. In response to Howarth and Paerl (2) we believe that the many similarities between responses of freshwater and estuarine systems that we discuss should not be totally ignored. Controlling nitrogen is a costly process, and we should expect conclusive evidence that it is effective.

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