Relationship between Polycyclic Aromatic Hydrocarbons in Sediments and Invertebrates of Natural and Artificial Stormwater Retention Ponds
, Hans Brix 2, Morten L. Fejerskov 3 and Asbjørn H. Nielsen 1Round 1
Reviewer 1 Report
This manuscript discusses the PAH concentration levels in sediments and invertebrates from stormwater retention ponds in Denmark. The method of experimentation is suitable for the purpose. It includes a satisfactory and properly selected list of relevant references. However, I suggest that it should be accepted for publication after major revisions described below.
Abstract: It should be supplemented with the most important PAH concentration data. Please also give the country of sampling sites.
34. line: Please give the full name before the first abbreviation (HELCOM).
2.1. Sampling sites description and sample collection: A map about the sampling sites would be useful. Information about the heavy metal measurements is not necessary in this manuscript. E. g. Identical sampling sites were analysed for heavy metal concentrations [31]. Another SWRP, PI2, was from previous studies known to receive illicit discharges with high contents of copper and zinc.
245-246 lines: Please give a reference.
Fig. 2: The concentration unit is missing.
Please check the concentration units in the full manuscript including sentences, figures and tables and use only one type of them. E.g. mg kg-1, µg kg-1 dry weight, mg (kg DM)-1)
In some sentences it was mention that the high molecular weight PAHs could be identified, while the low molecular weight PAHs were similar in concentration. However, the percentage values were not given.
A table containing the quality standards used for the assessments in this work may be useful.
3.3 General discussion: It seems too short. More detailed description about the findings would be necessary.
Conclusion: The PAH concentrations have been measured for 10 years. Therefore, some sentences about the importance of the up-to-date concentration data of PAHs or plan to continue this work would be useful at the end of the Conclusion section.
Author Response
Please see the attachment
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The article compares the content of hydrocarbons in sediments and invertebrates of various water bodies. The article meets the thematic requirement for the journal. In my opinion, it can be published, but I propose to take into account the following suggestions and complete the information on the methodology.
- Was the distribution of results normal?
- Did the authors observe any dependence of PAH concentrations on the depth of water bodies?
- Please provide information on the test used in point 2.3.
- A new table can be used to compile results on the significance of differences in PAH concentrations between tested water bodies.
- Lines 205-208 - isn't that too much of a generalization? Concentrations are very different.
- Please add the abbreviations used in the article for individual organic compounds in the diagrams.
- Lines 218-219 - I propose to rewrite it to specifically indicate that BPY concentrations in SWRP were significantly higher than in lakes.
- The information in Lines 269-281 can be combined in a new table - this will facilitate the perception of the text.
- Point 3.3 is actually a summary, and I propose that the information contained therein be included in points 3.1 and 3.2 and in point 4.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Reviewer 3 Report
The manuscript reports on an experimental investigation concerning the content of polycyclic aromatic hydrocarbons in sediments and invertebrates from 9 stormwater retention ponds and 11 natural shallow lakes.
The article is an original contribution and the topic is of interest for the readership of the Water journal.
English language is clear and the presentation is adequate; anyway, I have detected some criticisms in the text that should be properly addressed. Information on rainfall and temperature in the sampling period should be included.
The Authors can benefit from the comments below to improve their paper. These have to be accomplished before manuscript acceptance.
Abstract
The abstract is concise and reflects the content of the article.
A brief sentence should be added on the relevance of the research outcomes.
Introduction
Aims of the study are clarified in the Introduction.
Line 59-60: Concerning the required “treatment of stormwater runoff prior to discharge”, the Authors are recommended to mention also stormwater detention tanks together with stormwater retention ponds. In this regard, the Author are recommended to consider the following references as part of the introductory discussion:
- Todeschini S., Papiri S., Ciaponi C. (2012). Performance of stormwater detention tanks for urban drainage systems in northern Italy. Journal of Environmental Management, 101: 33-45, DOI: 10.1016/j.jenvman.2012.02.003.
- Calabrò, P.S., Viviani, G., 2006. Simulation of the operation of detention tanks. Water Research, 40 (1), 83-90. doi:10.1016/j.watres.2005.10.025.
Materials and Methods
This section is clear and adequately detailed.
Line 80: Is the community of invertebrates influenced by the period of sample collection? Discuss on this point. I suggest the Authors to include some information on rainfall and temperature in the sampling period from April to November 2010.
Results and Discussion
Results are presented in a logical sequence. The provided figures are necessary for the presentation and the understanding of the results. Discussion is interesting and supported by relevant references.
Conclusion
Conclusions seem reasonable and are supported by the results. I suggest the Authors to emphasize the implications of the obtained results.
References
Two references are suggested in the “Introduction” Section on the topic of the control of stormwater runoff prior to discharge by means of stormwater detention tanks. Apart from these references, based on my knowledge, no important reference is missing.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The suggestions have been incorporated into the manuscript. The revised version is okay now.
Reviewer 3 Report
The manuscript has been significantly improved following the recommendations of the Reviewers; all my concerns have been addressed and convincingly justified.
