Simulating Phosphorus Load Reductions in a Nested Catchment Using a Flow Pathway-Based Modeling Approach

Round 1

Reviewer 1 Report

·        The topic is very relevant and important, and the study is applying an interesting range of methods to address the questions posed.

·        The overall length of the manuscript is very long and will likely need to be cut down for publication, for example, the introduction could be cut down in section 1.1, which runs very long. It may be worth considering splitting this into 2 separate papers (see below).

·        There is a lot of research being squeezed into a single paper here. As far as I know the modifications to the model haven’t been previously published, so the model development and modification could probably be a stand-alone paper. This could work as a Part 1 / Part 2 paper, with the first focused on model development (i.e., presentation of the new model version and comparison of performance on key sub-catchments) and the second on model application (i.e., applying the new model to the entire catchment and inclusion of the mitigation scenarios).

·        The overall structure of the introduction and methods are a bit mixed, as some parts of the introduction I’d expect in the methods (i.e., site description) while parts of the methods may fit better in the intro (e.g., review of other studies). Again, this might be a case where 2 papers would resolve this by focusing the introduction onto a more constrained topic.

·        Some of the notations used are unclear and could be confusing to readers who typically associate them with a different meaning (e.g., C = concentration vs carbon). Maybe using P_L and P_c for loads and concentrations would give more clarity.

·        Other recommendations, suggestions, and edits throughout the manuscript are provided directly in the attached pdf.

Comments for author File: Comments.pdf

Author Response

Please see the attached Word document

Author Response File: Author Response.docx

Reviewer 2 Report

Comments for author File: Comments.pdf

Author Response

Please see the attached Word document

Author Response File: Author Response.docx