Latitudinal and Altitudinal Gradients of Riverine Landscapes in Andean Rivers

Round 1

Reviewer 1 Report

Thank you for the opportunity to review this paper by Habit et al. entitled “Latitudinal and altitudinal gradients of riverine landscapes in Andean rivers”. The authors 1) establish Functional Process Zones, following Thorp et al. (among others), in 11 watersheds in Chile; 2) describe these FPZs and draw similarities among watersheds, and 3) discuss the contribution of the Andes Cordillera in shaping the hydrogeomorphology of these drainages.

 

This work is important and worthy of publishing in Water. It provides an important baseline for studying Chilean drainages, assessing human impacts on them, and potentially allowing cross-continental and global comparison of riverine macrosystems structure and functioning. Additionally, the manuscript is well written and needs only a few minor linguistic corrections.

 

Below are my comments on the manuscript that are primarily intended to increase clarity in the methods and the overall presentation of the manuscript.

 

Line 176: A space is missing before 1.5 km. How the segmentation was carried out?  Was it defined by topographic characteristics or simply, a priori, by the authors? If so, why? 

 

Lines 184-186: Geology is a categorical variable. Was it used in the FPZ delineation or simply as a variable to describe the FPZs? In many previously published papers using this approach, the latter was the case.

 

Lines 198-194: Similarly, for channel platform and confinement, these two variables are also categorical. Please clarify if they were actually used in the categorization FPZs or simply linked to the FPZs for descriptive purposes.

 

Line 194-199: Why transects were automatically generated here? Please justify, and explain why other variables were collected at different distances between transects (i.e., 1.5 to 3 km).

 

Lines: 210-211. The authors exclude elevation and precipitation from the analysis to allow the formation of homogeneous FPZ groups. While this can be justified, it weakens the statement that this paper describes the altitudinal gradient of drainages. Did the authors compare clusters of FPZs with and without elevation and precipitation included in the analysis? If yes, they need to elaborate on what are the benefits of this exclusion. Of course, other valley- and channel-scale variables do reflect the longitudinal hydrogeomorphological changes that occur in an undisturbed river system, however, it is still necessary to justify why elevation and precipitation were excused, and maybe add in Table 1 the average values and SD of these variables.   

 

Line 247: Table 3 is missing, please include this table in your revision. Also, 1) I believe that it is not necessary to keep the FPZ in the naming of your FPZs in the text. i.e., AHA-FPZ or ASDS-FPZ can be replaced by AHA and ASDS; 2) the naming of FPZs is not homogeneous across the figures and appendices.

 

Line 260: Please spell out the 16 variables in the Figure caption.

 

Line 279: “the” is missing before eleven river basins.

 

Line 308: Please add a reference for macroinvertebrate communities, as you did for fish and food webs.

 

Line 327-328: This statement is wrong and needs to be rephrased. The RES states clearly that the distribution of FPZs is only partially predictable. Also, you show upstream-downstream patterns in the distribution of FPZs. This pattern can be different among watersheds, however, it is there and you cannot simply state that the distribution of FPZs is completely dissociated from an upstream-downstream pattern.

 

Lines 434-437: Delete. This is a repetition of the method and is not needed in the discussion.

 

Author Response

Please see the attached file.

Kind regards,

Evelyn Habit (also on behalf of the co-authors)

University of Concepción

Author Response File: Author Response.docx

Reviewer 2 Report

Comments for author File: Comments.doc

Author Response

Please see the attached file.

Kind regards,

Evelyn Habit (also on behalf of the co-authors)

University of Concepción

Author Response File: Author Response.docx

Reviewer 3 Report

Study is well-executed and extremely well-written. Creation of functional process zones for Chilean rivers will be an excellent touchstone for management and conservation. Method will be widely applicable to other regions.

A few typos are noted in the attached.  

Comments for author File: Comments.pdf

Author Response

Please see the attached file.

Kind regards,

Evelyn Habit (also on behalf of the co-authors)

University of Concepción

Author Response File: Author Response.docx