Riparian Buffers as a Critical Landscape Feature: Insights for Riverscape Conservation and Policy Renovations
Round 1
Reviewer 1 Report
Title: Riparian Zones as a Critical Landscape Feature: Insights for Riverscape Conservation and Policy Renovations
The manuscript reviews the topic of the riparian zones, which is one of the most important issues in the conservation of environment. Beside the review it also discusses the possibilities of the new approaches in the conservation of these underestimated parts of riverine ecosystems. The width of the riparian zones has been insufficient in many countries due to interests and pressures of land-owners and farmers, respectively. So, every contribution to raise the attention of the scientific audience and to educate local governments and owners is welcome. The manuscript is well written and concise. However, there are some corrections needed to improve it.
General comments:
You use also three other terms for Riparian Zones: Riparian Buffers (ln 524, 590), Riparian Areas (ln 41, ln 166, 523), Riparian Systems (ln 46); and Riparian Ecosystems (ln 157, 189). Please improve consistence and use the term Riparian Zones throughout the entire text. This term is also in the title.
You start the Introduction (ln 34) with the sentence: The transitional aquatic-terrestrial interface surrounding lotic systems are broadly defined as riparian zones, …. Which assign the Riparian Zones a rather secondary or marginal role. Riparian zones are a part of riverine ecosystem, and in this sense the first sentence should be:
“Riparian zones are influenced by hydrodynamic forces in lotic ecosystems (rivers and streams) and represent an outer border of these ecosystem, and as such have numerous functions. They connect terrestrial and aquatic habitats through …..”
Check the terminology of different fractions of organic matter, for instance in Allan & Castillo 2007, (Chapter 7), which you cite. Fine organic matter is fine particulate organic matter (FPOM); Ln 110-112.
Woody debris is not direct nutrient source for detritivores and shredders; the food source for shredders is mostly leaf-litter (CPOM) and in some cases also macrophytes; detritivores are a group of benthic invertebrates that feed on fine particulate organic matter (FPOM), which sources are multiple (decay of CPOM, sloughing of benthic algae, upper soil layer, etc.) comes into streams
Minor corrections:
Title: I suggest to reorganize the title to: “Critical role of Riparian zones: insights for Conservation of Watercourses and Landscapes.”
Abstract:
Ln 12: moist microclimates … I suggest: wet habitats
Ln 13: constant nutrient influx
Ln 14: rich in biodiversity instead high
Ln 14-15: riparian vegetation supplies woody debris into the streams, but also leaf-litter or CPOM (more general) which exceeds the wood in the amount (volume and surface) and supports much higher number of invertebrates than wood.
Introduction:
Ln 37: please remove the word “also”
Ln 41: please see comment above for Riparian Zones/Areas/Buffers /Ecosystems
Ln 44: please define the term riverscapes, since many readers are not familiar with it
Ln 110-112: Please correct: fine organic matter is fine particulate organic matter (FPOM);
Woody debris is not direct nutrient source for detritivores and shredders; the food source for shredders is mostly leaf-litter (CPOM) and in some cases also macrophytes; detritivores are a group of benthic invertebrates that feed on fine particulate organic matter (FPOM), which sources are multiple (decay of CPOM, sloughing of benthic algae, upper soil layer, etc.)
(see Allan & Castillo 2007, Chapter 7)
Ln 121: I suggest to use the generally used terms for feeding-guilds of macroinvertebrates also here: replacement of shredders and predators with grazers (invertebrates grazing periphyton are in fact omnivorous rather than herbivores since these biofilms consist of algae as well as bacteria and protozoans. t:
Ln 127: Please correct: Riparian vegetation supplies particulate organic matter (POM) in the form of leaves and woody debris of variable sizes…..
Ln 396 and 450: Please check the style of citation: Olson et al.
Figure 1. I think that a bit smaller Figure would still be readable, please use the reasonable size.
Figure 2. Please color the Wetlands as defined in the Legend.
Ln 590: Please add “erosion” (e.g. flood and erosion prevention)
Ln 597: Please add “riverine” … a vital riverine and riverscape element …
Author Response
R1
Comments and Suggestions for Authors
Title: Riparian Zones as a Critical Landscape Feature: Insights for Riverscape Conservation and Policy Renovations
RC: The manuscript reviews the topic of the riparian zones, which is one of the most important issues in the conservation of environment. Beside the review it also discusses the possibilities of the new approaches in the conservation of these underestimated parts of riverine ecosystems. The width of the riparian zones has been insufficient in many countries due to interests and pressures of land-owners and farmers, respectively. So, every contribution to raise the attention of the scientific audience and to educate local governments and owners is welcome. The manuscript is well written and concise. However, there are some corrections needed to improve it.
AR: we appreciate your constructive criticism and all suggestions. Those suggestions most certainly made significant improvements in our manuscript. We are grateful for your time. Following, we provided our responses to both specific and general comments by the reviewers.
General comments:
Reviewer comments (RC): You use also three other terms for Riparian Zones: Riparian Buffers (ln 524, 590), Riparian Areas (ln 41, ln 166, 523), Riparian Systems (ln 46); and Riparian Ecosystems (ln 157, 189). Please improve consistence and use the term Riparian Zones throughout the entire text. This term is also in the title.
Author response (AR): We agree that there should be consistency with respect to these terms. We removed the terms “riparian ecosystems” and “riparian areas” from the ms. We do want to strike the difference between zone vs buffers though. In our revisions, we consistently used the term “buffer” when we are specifically referring to buffered riparian zones. When we are generally referring to riparian zones with or without a buffer, we opt for the term riparian zone. Therefore, there are a few instances we continue to use the term “riparian zone” in the revised ms as well. Not all riparian zones are buffered. Therefore, we think it is important to variably use these two terms, depending on the specific context.
RC: You start the Introduction (ln 34) with the sentence: The transitional aquatic-terrestrial interface surrounding lotic systems are broadly defined as riparian zones, …. Which assign the Riparian Zones a rather secondary or marginal role. Riparian zones are a part of riverine ecosystem, and in this sense the first sentence should be:
“Riparian zones are influenced by hydrodynamic forces in lotic ecosystems (rivers and streams) and represent an outer border of these ecosystem, and as such have numerous functions. They connect terrestrial and aquatic habitats through …..”
AR: We agree with this revision and this sentence is now updated as suggested.
RC: Check the terminology of different fractions of organic matter, for instance in Allan & Castillo 2007, (Chapter 7), which you cite. Fine organic matter is fine particulate organic matter (FPOM); Ln 110-112.
Woody debris is not direct nutrient source for detritivores and shredders; the food source for shredders is mostly leaf-litter (CPOM) and in some cases also macrophytes; detritivores are a group of benthic invertebrates that feed on fine particulate organic matter (FPOM), which sources are multiple (decay of CPOM, sloughing of benthic algae, upper soil layer, etc.) comes into streams
AR: this is a good point. we made all these clarifications in this section
Minor corrections:
RC: Title: I suggest to reorganize the title to: “Critical role of Riparian zones: insights for Conservation of Watercourses and Landscapes.”
AR: we appreciate this suggestion. However, the goal of our paper goes beyond discussing the role of riparian zones, rather we strive to promote riparian zone as a critical feature of the landscape. Besides, the term watercourse has a much broader definition, even in the English-speaking world. Some policy definitions even consider constructed canals, lakes, ponds, anything with surface water as a watercourse. We prefer to refrain from that term as well.
Abstract:
RC: Ln 12: moist microclimates … I suggest: wet habitats
AR: “wet habitats” may not be ideal in this context. Presence of microenvironments with high moisture content are not necessarily wet—thus gives the wrong impression. We opt to raitain microenvironment
RC: Ln 13: constant nutrient influx
AR: revised as suggested
RC: Ln 14: rich in biodiversity instead high
AR: revised as suggested
RC: Ln 14-15: riparian vegetation supplies woody debris into the streams, but also leaf-litter or CPOM (more general) which exceeds the wood in the amount (volume and surface) and supports much higher number of invertebrates than wood.
AR: This is an excellent suggestion. We revised the abstract to include CPOM input.
Introduction:
RC: Ln 37: please remove the word “also”
AR: word “also” now deleted
RC: Ln 41: please see comment above for Riparian Zones/Areas/Buffers /Ecosystems
AR: We agree with for the need for consistency. Please see our general response above.
RC: Ln 44: please define the term riverscapes, since many readers are not familiar with it
AR: good point! we added a broader definition to riverscape from the most recent articles.
RC: Ln 110-112: Please correct: fine organic matter is fine particulate organic matter (FPOM);
Woody debris is not direct nutrient source for detritivores and shredders; the food source for shredders is mostly leaf-litter (CPOM) and in some cases also macrophytes; detritivores are a group of benthic invertebrates that feed on fine particulate organic matter (FPOM), which sources are multiple (decay of CPOM, sloughing of benthic algae, upper soil layer, etc.)
(see Allan & Castillo 2007, Chapter 7)
AR: We agree with this correction. this section is not corrected to indicate that CPOM and FPOM as the energy sources for the benthos
RC: Ln 121: I suggest to use the generally used terms for feeding-guilds of macroinvertebrates also here: replacement of shredders and predators with grazers (invertebrates grazing periphyton are in fact omnivorous rather than herbivores since these biofilms consist of algae as well as bacteria and protozoans. t:
AR: we corrected our references as recommended. However, the statement we made is not specific to the macroinvertebrates rather to all stream biota.
RC: Ln 127: Please correct: Riparian vegetation supplies particulate organic matter (POM) in the form of leaves and woody debris of variable sizes…..
AR: sentence corrected as suggested.
RC: Ln 396 and 450: Please check the style of citation: Olson et al.
AR: we corrected the intext citation style for all the citations.
RC: Figure 1. I think that a bit smaller Figure would still be readable, please use the reasonable size.
AR: we reduced the image size considerably, however, the editors determine the true image size and scaling. Ultimately, this is up to them to decide.
RC: Figure 2. Please color the Wetlands as defined in the Legend.
AR: the fig is not corrected as suggested.
RC: Ln 590: Please add “erosion” (e.g. flood and erosion prevention)
AR: corrected as suggested
RC: Ln 597: Please add “riverine” … a vital riverine and riverscape element …
AR: corrected as suggested
Reviewer 2 Report
The paper provides an updated review of the importance and riparian zones, highlighting the challenges of an effective delineation and conservation policies. The paper is very well written and structured, and it’s very updated, including relevant and recent papers on the topic. However, in my opinion the manuscript reads more like an essay than a scientific paper, and I personally won’t recommend publishing it as it is. My concern is that the literature review is nicely done, but that the set of recommendations provided between lines 431 and 522 are not based on any evidence or directly from the literature review. in my opinion, there are too many “it should be done”, “it is imperative to”, “we encourage”, “we discourage”. Although I essentially agree with all these recommendations, I have to say that those sentences are not supported by evidence, and read more like speculative personal stances. I would thus not recommend to publish the manuscript as it is. I would suggest the Authors to consider two alternatives in order to restructure the paper. The first option would be to transform the manuscript into a proper literature review. In this case, the text between 431 and 522 should be deleted or profoundly rewritten, and the paper should have a final chapter with perspective, gaps in our understanding, open and future challenges for reach and applicative efforts, and ways forward, but all strictly based on the review. The alternative would be to keep the text between 431 and 522, but to support it properly with some evidence, perhaps a pilot study case. Figures 1 and 2 seem like results from an application. I think that this application could be presented and discussed, and this would be an original contribution, that could also support the recommendations, that could otherwise be considered speculative.
Author Response
R2
Comments and Suggestions for Authors
RC: The paper provides an updated review of the importance and riparian zones, highlighting the challenges of an effective delineation and conservation policies. The paper is very well written and structured, and it’s very updated, including relevant and recent papers on the topic. However, in my opinion the manuscript reads more like an essay than a scientific paper, and I personally won’t recommend publishing it as it is.
AR: we appreciate these supportive remarks and time taken to complete the review. However, we respectfully disagree with you. This manuscript was authored following a scientific style, as a review, not as an essay. Had you pointed out which elements/sections of the paper or which aspect of writing makes it look like an essay, we could’ve considered your criticism. Instead, this is no more than an unfounded personal opinion. Besides, your criticism is in stark contrast to recommendations and suggestions from two other reviewers, both provided very detailed feedback (with constructive criticism as opposed to unfound personal opinions) compared to yours. We urge you to carefully and completely read the manuscript.
RC: My concern is that the literature review is nicely done, but that the set of recommendations provided between lines 431 and 522 are not based on any evidence or directly from the literature review. in my opinion, there are too many “it should be done”, “it is imperative to”, “we encourage”, “we discourage”. Although I essentially agree with all these recommendations, I have to say that those sentences are not supported by evidence, and read more like speculative personal stances. I would thus not recommend to publish the manuscript as it is. I would suggest the Authors to consider two alternatives in order to restructure the paper. The first option would be to transform the manuscript into a proper literature review. In this case, the text between 431 and 522 should be deleted or profoundly rewritten, and the paper should have a final chapter with perspective, gaps in our understanding, open and future challenges for reach and applicative efforts, and ways forward, but all strictly based on the review. The alternative would be to keep the text between 431 and 522, but to support it properly with some evidence, perhaps a pilot study case.
AR: We 100% agree with your inputs on “perspective, gaps in our understanding, open and future challenges for reach and applicative efforts, and ways forward..”; in factthese parts are already included in the current ms, most notably in the sections you deemed “speculative”. Adding a separate section on these themes would be redundant. We do agree that a scientific review should not have speculative statements and we do not have such speculations in the current ms. The section you are referring to contains numerous citations (just like you suggested), thus are evidence-based statements. Without this section (431-522), our manuscript carries very little novelty. The other two reviewers explicitly pointed out that this section is the key part of the ms. Therefore, deleting that section will go against the opinion of two other reviewers, as well as ourselves. Without a proper synthesis, a mere amalgamation of information will make the manuscript scientifically unsound, dull, and unoriginal. I cannot think about a single indexed journal that accepts reviews without a synthesis. We agree that doing a pilot case study is a prudent idea—but, our idea is to produce a review, not a case-study based research paper.
RC: Figures 1 and 2 seem like results from an application. I think that this application could be presented and discussed, and this would be an original contribution, that could also support the recommendations, that could otherwise be considered speculative.
AR: We have discussed the buffer designs pictured here, particularly in the section you wanted us to delete. These figures were modified versions of diagrams published in peer-reviewed journals, and the original papers are already cited.
Reviewer 3 Report
General comment:
This is a very well written review paper that discusses the ecological benefits of riparian zones, and their main stressors and conservation challenges, to ultimately suggest a better consideration and definition of buffer zones in river policies. Even though the paper is only intended to address the USA context, the logic behind and conclusions supported by this paper are applicable to other world regions, and therefore I consider this work of potential interest of international readers of Diversity. The paper has been very carefully written, and I can tell the authors really master the topic. It has been a pleasure to review (which is rare nowadays).
Regarding the structure of the review paper, questions 1 (benefits) and 2 (threats and conservation challenges) are not particularly novel, but they are a nice synthesis and set the ground for the development of question 3 (conservation actions and policy reforms), which is where the authors really develop new material with new guidelines for the delimitation of a strategy for conservation of riparian zones.
I think the paper could be accepted for publication after the following minor revisions are addressed. Most are editorial comments and suggestions for adding some ideas that may have been overlooked:
Page 1 lines 21-23. I found this sentence repetitive with the previous. Try to merge them.
Page 2 line 51. Consider citing Riis et al. 2020
Riis, T., Kelly-Quinn, M., Aguiar, F. C., Manolaki, P., Bruno, D., Bejarano, M. D., ... & Dufour, S. (2020). Global overview of ecosystem services provided by riparian vegetation. BioScience, 70(6), 501-514.
Page 2 line 57. “ecosystem services and functions” (the last paragraph is about functions, not services)
Page 2 line 56. I think the reason for the recognition of conservation is not only the realization of ES provided, but also the perception of the degradation that these systems have experienced.
Page 3 line 101. Not clear. What are “interior forests”? Do you mean forests in the central states of US? Or a seral successional stage different from hardwood forests?
Page 3 line 133. Are you sure you don’t mean “low-flow” seasons here?
Page 4 line 153. Still talking about macroinvertebrates? (not about fishes or other life forms, right?)
Page 4 line 159. I would say “more resistant” as compared to other ecosystems. I find a bit daring to call them resistant.
Page 4 lines 160-163. these are all morphological can you give one example of physiological?
Page 5 line 198. Did you mean hydrochory?
Page 5 line 213. Typo. “avascular >> a vascular”
Page 5 lines 216-217. Are we talking about larvae and migration of fishes only here?
Page 5 lines 227-228. At least in the first phase, as the process of plant invasions is more complex, usually sequential
Page 5 lines 241-244. mining activities in watersheds are also an important source of metal pollution in water and sediments
Page 6 Section 4.5. Here it would be also worth mentioning that river channels are also private if crossing private lands. This is a fundamental difference relative to other countries (e.g., Europe), where river channels are public, and access must be warranted. Also, water allocation and water rights are very different from other countries. Maybe say a couple sentences about this.
Page 6 line 270 Typo, local not locale
Page 8 line 357 Typo Thence Hence?
Page 8 lines 372-373. I would add “channel planform” to this list
Page 8 line 393. A good paper on legacies is:
Wohl, E. (2019). Forgotten legacies: understanding and mitigating historical human alterations of river corridors. Water Resources Research, 55(7), 5181-5201.
Page 9. This is a general comment, but this section made me think about this. When delineating riparian zones / buffer zones, my understanding is that flood risk rather than habitat conservation criteria is frequently used as criteria. Depending on return periods, certain types of human activities such as certain types of urban development may be not allowed. I think using the flood risk criterium is still valid, and compatible with what you suggest here.
Page 12 line 479. I wonder if “debris flows” would be a more appropriate term than “landslides”
Page 12 line 492. “and species of interest”
Page 12 line 501-503.
There are several recent papers that summarize the main concerns and challenges of dam removal, worth checking.
Tullos, D. D., Collins, M. J., Bellmore, J. R., Bountry, J. A., Connolly, P. J., Shafroth, P. B., & Wilcox, A. C. (2016). Synthesis of common management concerns associated with dam removal. JAWRA Journal of the American Water Resources Association, 52(5), 1179-1206.
Foley, M. M., Bellmore, J. R., O'Connor, J. E., Duda, J. J., East, A. E., Grant, G. E., ... & Wilcox, A. C. (2017). Dam removal: Listening in. Water Resources Research, 53(7), 5229-5246.
Bellmore, J. R., Pess, G. R., Duda, J. J., O’Connor, J. E., East, A. E., Foley, M. M., ... & Craig, L. S. (2019). Conceptualizing ecological responses to dam removal: If you remove it, what's to come?. BioScience, 69(1), 26-39.
Page 13 Section 6
I know the scope of the review is the USA, but this section would benefit from adding a couple of examples on how the legislation in other countries have addressed buffer delimitation.
For example, in other countries, flood risk is used as a criterium to delimitate buffer zones with different land uses or activities allowed. See for example the Floods and Water Framework directives of the EU. Are there any successful initiatives worldwide that could be applied to the US case?
In francophone countries, the “espace de liberté” – “freedom space” concept is being used, or at least, discussed in academic circles. See for example:
Canada:
Biron, P. M., Buffin-Bélanger, T., Larocque, M., Choné, G., Cloutier, C. A., Ouellet, M. A., ... & Eyquem, J. (2014). Freedom space for rivers: a sustainable management approach to enhance river resilience. Environmental management, 54(5), 1056-1073.
Spain: - concept of “fluvial territory”
Ollero, A. (2010). Channel changes and floodplain management in the meandering middle Ebro River, Spain. Geomorphology, 117(3-4), 247-260.
Page 13 lines 555-556
Or, it is only sufficient in few cases (some low order streams in headwaters)
Author Response
R3
Comments and Suggestions for Authors
General comment:
RC: This is a very well written review paper that discusses the ecological benefits of riparian zones, and their main stressors and conservation challenges, to ultimately suggest a better consideration and definition of buffer zones in river policies. Even though the paper is only intended to address the USA context, the logic behind and conclusions supported by this paper are applicable to other world regions, and therefore I consider this work of potential interest of international readers of Diversity. The paper has been very carefully written, and I can tell the authors really master the topic. It has been a pleasure to review (which is rare nowadays).
AR: we appreciate the kind, generous words! These are particularly encouraging for us
RC: Regarding the structure of the review paper, questions 1 (benefits) and 2 (threats and conservation challenges) are not particularly novel, but they are a nice synthesis and set the ground for the development of question 3 (conservation actions and policy reforms), which is where the authors really develop new material with new guidelines for the delimitation of a strategy for conservation of riparian zones. I think the paper could be accepted for publication after the following minor revisions are addressed. Most are editorial comments and suggestions for adding some ideas that may have been overlooked:
AR: we agree that the benefits/functions and treats/conservation challenges aren’t particularly novel or unknown. The point of these parts is to provide a detailed overview of the subject and to review the background materials. Despite the exhaustive literature on these two parts, we aren’t aware of a comprehensive review on these themes. The novelty comes in the conservation actions and policy recommendations. We need to be extra careful on overreaching in these guidelines to avoid being speculative.
RC: Page 1 lines 21-23. I found this sentence repetitive with the previous. Try to merge them.
AR: agreed about the repetition. This sentence is now changed. It would be hard to combine the two sentences without complicating the sentence structure.
RC: Global overview of ecosystem services provided by riparian vegetation
Page 2 line 51. Consider citing Riis et al. 2020
Riis, T., Kelly-Quinn, M., Aguiar, F. C., Manolaki, P., Bruno, D., Bejarano, M. D., ... & Dufour, S. (2020). Global overview of ecosystem services provided by riparian vegetation. BioScience, 70(6), 501-514.
RC: Page 2 line 57. “ecosystem services and functions” (the last paragraph is about functions, not services)
AR: corrected as suggested
RC: Page 2 line 56. I think the reason for the recognition of conservation is not only the realization of ES provided, but also the perception of the degradation that these systems have experienced.
AR: good point, the degradation is not included in this statement as a reason for conservation
RC: Page 3 line 101. Not clear. What are “interior forests”? Do you mean forests in the central states of US? Or a seral successional stage different from hardwood forests?
AR: We were referring to the forests located further away from the stream channel. We corrected this sentence to clarify this.
RC: Page 3 line 133. Are you sure you don’t mean “low-flow” seasons here?
AR: it should be low-flow, our mistake. This is now corrected.
RC: Page 4 line 153. Still talking about macroinvertebrates? (not about fishes or other life forms, right?)
AR: this example was about freshwater turtles—which is now clarified with revisions.
RC: Page 4 line 159. I would say “more resistant” as compared to other ecosystems. I find a bit daring to call them resistant.
AR: we agree, in fact, we changed this sentence to include to resistance and resilience
RC: Page 4 lines 160-163. these are all morphological can you give one example of physiological?
AR: some of these traits we mentioned are combined products of both physiological and morphological adaptations, as mentioned by the referenced citation and references therein (Capon et al 2013). We added a couple of other adaptations that are rather physiological—disturbance tolerance and tolerance to soil conditions.
RC: Page 5 line 198. Did you mean hydrochory?
AR: this term is not corrected as suggested
RC: Page 5 line 213. Typo. “avascular >> a vascular”
AR: we meant avascular—we figured that nonvascular is a better term.
RC: Page 5 lines 216-217. Are we talking about larvae and migration of fishes only here?
AR: the cited references are about fish. And we added that clarification into the revisions.
RC: Page 5 lines 227-228. At least in the first phase, as the process of plant invasions is more complex, usually sequential
AR: we agree—the statement is now corrected to include early establishment
RC: Page 5 lines 241-244. mining activities in watersheds are also an important source of metal pollution in water and sediments
AR: fundamentally, we agree. But, this section is about impact on the riparian zone. It would be hard to link the mining in rest of the watershed to riparian-zone degradation. While we agree that can damage the stream channel, mentioning that here can be confusing to the reader. thus, we did make any corrections to this account.
RC: Page 6 Section 4.5. Here it would be also worth mentioning that river channels are also private if crossing private lands. This is a fundamental difference relative to other countries (e.g., Europe), where river channels are public, and access must be warranted. Also, water allocation and water rights are very different from other countries. Maybe say a couple sentences about this.
AR: we fundamentally agree with this point, but making a categorical statement is a bit tricky since protection at state or local level can be variables. however, we acknowledged this limitation as it pertains to conservation of riparian systems.
RC: Page 6 line 270 Typo, local not locale
AR: corrected
RC: Page 8 line 357 Typo Thence Hence?
AR: we first thought thence might be a better fit, but, it appears that hence is a best word here. now it is corrected.
RC: Page 8 lines 372-373. I would add “channel planform” to this list
AR: excellent suggestion, we included “channel planform” into this list including a brief parenthetical definition.
RC: Page 8 line 393. A good paper on legacies is:
Wohl, E. (2019). Forgotten legacies: understanding and mitigating historical human alterations of river corridors. Water Resources Research, 55(7), 5181-5201.
AR: this is an excellent reference; we included a couple of sentences into the end of section 5.3
RC: Page 9. This is a general comment, but this section made me think about this. When delineating riparian zones / buffer zones, my understanding is that flood risk rather than habitat conservation criteria is frequently used as criteria. Depending on return periods, certain types of human activities such as certain types of urban development may be not allowed. I think using the flood risk criterium is still valid, and compatible with what you suggest here.
AR: we agree. We added this part in section 5.3
RC: Page 12 line 479. I wonder if “debris flows” would be a more appropriate term than “landslides”
AR: we 100% agree. Changed landsides to debris flow
RC: Page 12 line 492. “and species of interest”
AR: great suggestion, we included species of interest into this list.
RC: Page 12 line 501-503.
There are several recent papers that summarize the main concerns and challenges of dam removal, worth checking.
Tullos, D. D., Collins, M. J., Bellmore, J. R., Bountry, J. A., Connolly, P. J., Shafroth, P. B., & Wilcox, A. C. (2016). Synthesis of common management concerns associated with dam removal. JAWRA Journal of the American Water Resources Association, 52(5), 1179-1206.
Foley, M. M., Bellmore, J. R., O'Connor, J. E., Duda, J. J., East, A. E., Grant, G. E., ... & Wilcox, A. C. (2017). Dam removal: Listening in. Water Resources Research, 53(7), 5229-5246.
Bellmore, J. R., Pess, G. R., Duda, J. J., O’Connor, J. E., East, A. E., Foley, M. M., ... & Craig, L. S. (2019). Conceptualizing ecological responses to dam removal: If you remove it, what's to come?. BioScience, 69(1), 26-39.
AR: these are excellent suggestions. We strengthened the part on the importance of dam removal in riparian buffer conservation. We included all these three references in the revised section.
Page 13 Section 6
RC: I know the scope of the review is the USA, but this section would benefit from adding a couple of examples on how the legislation in other countries have addressed buffer delimitation.
For example, in other countries, flood risk is used as a criterium to delimitate buffer zones with different land uses or activities allowed. See for example the Floods and Water Framework directives of the EU. Are there any successful initiatives worldwide that could be applied to the US case?
In francophone countries, the “espace de liberté” – “freedom space” concept is being used, or at least, discussed in academic circles. See for example:
Canada:
Biron, P. M., Buffin-Bélanger, T., Larocque, M., Choné, G., Cloutier, C. A., Ouellet, M. A., ... & Eyquem, J. (2014). Freedom space for rivers: a sustainable management approach to enhance river resilience. Environmental management, 54(5), 1056-1073.
Spain: - concept of “fluvial territory”
Ollero, A. (2010). Channel changes and floodplain management in the meandering middle Ebro River, Spain. Geomorphology, 117(3-4), 247-260.
AR: We found these policy frameworks to be very useful. We added a small paragraph based on these publications.
RC: Page 13 lines 555-556
Or, it is only sufficient in few cases (some low order streams in headwaters)
AR: this is a good point, we corrected our statement to indicate that 30-m buffers might work for low-order systems
Round 2
Reviewer 1 Report
Manuscript ID: diversity-1518163
Title: Riparian Zones as a Critical Landscape Feature: Insights for Riverscape Conservation and Policy Renovations
The authors have corrected some of the issues, but some important have remained unsolved. I think that some of the comments, when correctly addressed would increase the chances for the proper management of the riparian zones in the future. Every attempt to educate local governments, farmers and landowners is welcome. I suggest the authors to reconsider these comments and continue with corrections. I suggest minor changes.
Comments:
You chose the term Buffers instead of the Zones. The advantage of the term riparian Buffers in comparison with Zones is that it emphasizes their protective role and mitigation of an influence.
You started the Introduction in first version with the sentence: The transitional aquatic-terrestrial interface surrounding lotic systems are broadly defined as riparian zones, …. Which assign the Riparian Zones a rather secondary or marginal role. Riparian zones are a part of riverine ecosystem, and in this sense the first sentence should be:
“Riparian zones are influenced by hydrodynamic forces in lotic ecosystems (rivers and streams) and represent an outer border of these ecosystem, and as such have numerous functions. They connect terrestrial and aquatic habitats through …..”
I insist on emphasizing the Riparian Buffers as a part of riverine or fluvial ecosystem – see also the reference:
Dufour, S.; Rodríguez-González, P.M.; Laslier, M. Tracing the scientific trajectory of riparian vegetation
studies: Main topics, approaches and needs in a globally changing world. Sci. Total Environ. 2019, 653,
1168–1185.
Zelnik, I.; Mavrič Klenovšek, V.; Gaberščik, A. Complex Undisturbed Riparian Zones Are Resistant to Colonisation by Invasive Alien Plant Species. Water 2020, 12, 345.
I also think that treating them as an essential part of fluvial ecosystem would change the attitude of different sectors such as farmers, policy makers, landowners, planners and consequently this would enhance their protection.
Abstract:
Ln 12: moist microclimates … I suggest: wet habitats
Figure 1. I checked the definition by Semlitsch and Bodie (2003). I suggest using the same and to correct the legend and replace “core terrestrial habitat” with “core habitat”. Which points on the two sub-zones “Aquatic buffer” in dark green and “transitional zone” in medium green color.
Author Response
Comments:
Reviewer comments (RC): You chose the term Buffers instead of the Zones. The advantage of the term riparian Buffers in comparison with Zones is that it emphasizes their protective role and mitigation of an influence.
Author responses (AR): we agree, therefore we will retain “buffer” over zone.
RC: You started the Introduction in first version with the sentence: The transitional aquatic-terrestrial interface surrounding lotic systems are broadly defined as riparian zones, …. Which assign the Riparian Zones a rather secondary or marginal role. Riparian zones are a part of riverine ecosystem, and in this sense the first sentence should be: “Riparian zones are influenced by hydrodynamic forces in lotic ecosystems (rivers and streams) and represent an outer border of these ecosystem, and as such have numerous functions. They connect terrestrial and aquatic habitats through …..”
AR: thank you, we agree that our original version was less than ideal. However, I am not convinced that “outer boarder” is an accurate way to characterize riparian buffers. But, the current language is very similar to what you propose. We’d like to keep the revised version as is.
RC: I insist on emphasizing the Riparian Buffers as a part of riverine or fluvial ecosystem – see also the reference:
Dufour, S.; Rodríguez-González, P.M.; Laslier, M. Tracing the scientific trajectory of riparian vegetation studies: Main topics, approaches and needs in a globally changing world. Sci. Total Environ. 2019, 653, 1168–1185.
Zelnik, I.; Mavrič Klenovšek, V.; Gaberščik, A. Complex Undisturbed Riparian Zones Are Resistant to Colonisation by Invasive Alien Plant Species. Water 2020, 12, 345.
I also think that treating them as an essential part of fluvial ecosystem would change the attitude of different sectors such as farmers, policy makers, landowners, planners and consequently this would enhance their protection.
AR: we agree on this point 100%. We included several points from these two papers into the manuscript.
Abstract:
RC: Ln 12: moist microclimates … I suggest: wet habitats
AR: like we mentioned last time, these two are not the same, we prefer to use moist microclimates
RC: Figure 1. I checked the definition by Semlitsch and Bodie (2003). I suggest using the same and to correct the legend and replace “core terrestrial habitat” with “core habitat”. Which points on the two sub-zones “Aquatic buffer” in dark green and “transitional zone” in medium green color.
AR: Figure 1. The figure corrected as suggested
