Modeling the Matrix-Conduit Exchanges in Both the Epikarst and the Transmission Zone of Karst Systems

Round 1

Reviewer 1 Report

Dear authors,

I appreciated very much your approach to numerically describe the role of epikarst in recharging karst groundwater and I have not actual remarks to do. Epikarst modelling surely is affected by many uncertainness due to the heterogeneity of this superficial zone, which much depends on geological and morphological features, but your simulation can improve the application of numerical models in those situation where epikarst exerts an important role on groundwater flow.

I have some minor revisions to suggest.

Line 11 – In English “confronted” has usually the meaning of “to face”, I suggest “compared”.

Lines 112-113 – According to my experience epikarst has a very anisotropic hydraulic conductivity (HC) and vertical HC can be higher than horizontal one. Maybe it would be enphasized that this model concerns the lower part of EK where HC mainly has a horizontal direction.

Lines 122 – In my experience, in the transmission zone the water flux is mainly vertical through solution fissures and caves (percolation pits). Faults are rare and often they have a reduced permeability due to precipitation process.

Line 163 – A single vertical conduit in the center of a 1 km2 square is quite unrealistic. Often, vertical flow conduits are spatially denser as testified by the density of dolines and/or pits in many bared karsts.  So, the model describes a condition that cannot be considered as representative in general.

Lines 172-173 – I suggest describing better the pattern of recharge event. If I understand well it consists of 100 mm distributed in two days with a central peak. Maybe a figure could help comprehension.

Lines 219-221 – I do not agree with these sentences. Epikarst usually has a vertical HC higher than horizontal one, even if water flux is forced to be horizontal toward high conductive conduits. Also in the transmission zone vertical HC is usually higher than horizontal one. Please, revise or clarify better.

Line 244 – Figure 2 – If the model considers a 1 km2 surface, why saturation index and hydraulic head are shown only 250 m around the vertical conduit? Please, explain in the text.

Author Response

Dear reviewer,

Please find attached our response to your review.

Best regards,

Charles Danquigny,

on the behalf of the authors

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments provided in the attached file

Comments for author File: Comments.pdf

Author Response

Dear reviewer,

Please find attached our response to your review.

Best regards,

Charles Danquigny,

on the behalf of the authors

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The authors responded to all my comments and accordingly corrected the manuscript, which has been significantly improved. I recommend it for publication.