Evaluation of Water Quality Parameters in Shatt AL-Arab, Southern Iraq, Using Spatial Analysis
Round 1
Reviewer 1 Report
All the figures have very poor quality, especially the figure 1.
This work is very complete, it even presents information that is too detailed (which was not necessary). However, the results of such work are compared to Iraqi Standards rather than international standards. I recommend, changing or expanding the interpretation of results with international standards.
Explain why they selected the parameters used. Because they did not determine others such as chemical oxygen demand, fecal coliforms, total nitrogen, pH, etc.
Comments for author File: 
Comments.docx
Author Response
hydrology-940644– Revised Manuscript
RC = Reviewer’s Comment; AR = Authors’ Response
Reviewer #1:
RC: “The work is very good; however, it needs major changes before publication. I can´t suggest publication at this stage.”
AR: The authors appreciated the reviewer acknowledgment of this manuscript. The authors made the required changes as suggested by the reviewers (see revised manuscript).
RC: “All the figures have very poor quality, especially the figure 1.”
AR: The authors adjusted all the figures with high resolutions (all figures now have 300 DPI resolutions). The authors also adjusted Figure 1 based on this comment and other reviewer’s comments (Please, see the revised manuscript).
RC: “This work is very complete, it even presents information that is too detailed (which was not necessary). However, the results of such work are compared to Iraqi Standards rather than international standards. I recommend, changing or expanding the interpretation of results with international standards.”
AR: The authors expanded the comparison to include International standards (WHO and European Union) (Please, see the “Results” section highlighted in red line). An example that added by authors can be found in Page 11, lines 345-348 in revised manuscript:
“The results revealed that most of the chloride concentrations exceeded the Iraqi and international standards. For example, during winter 2018, the chloride concentration in Al-Karma station was 1264 mg/l which is way higher than the Iraqi standards, WHO standards (250mg/l), and European Union standards (200mg/l).”
RC: “Explain why they selected the parameters used. Because they did not determine others such as chemical oxygen demand, fecal coliforms, total nitrogen, pH etc. “
AR: The current research is part of a master's thesis and the practical part ended at the end of December of 2019. In addition, the practical part included examining many elements, approximately 43 variables for each sample (chemical and physical tests, heavy and radioactive elements). Too much data was collected, and the focus was on those tests are related to increasing the salinity rate in the Shatt al-Arab, in addition to the focus on heavy elements. It is possible to benefit from other data by referring to it in future studies, especially the authors in the process of preparing continuous studies in this regard in the future.
Author Response File: Author Response.docx
Reviewer 2 Report
MDPI - Hydrology
Manuscript Number: Hydrology-940644
Title: Evaluation Water Quality Parameters in Shatt AL-Arab, Southern Iraq, using Spatial Analysis
Article Type: Research Paper
Keywords: Water quality parameters; River of Shatt Al-Arab; Salinity water; Arabian Gulf; Spatial analysis.
The authors provide illustrate the potential application of techniques of spatial analysis and Geographic Information Systems (GIS) to categorize the distribution of temporal and spatial of water predictions characteristics to determine the water quality parameters of the Shatt Al-Arab River (SAA), Southern Iraq.
The manuscript Hydrology-940644 is well written and represents a valuable contribution to the literature. I believe this manuscript should be published after a major revision. The revision should include a better geological description followed by a schematic geological map to get an overview of the results obtained. Furthermore, the paper should be improved with a geochemical characterization.
Comments (P = page/ R = row):
P1-2/Introduction: Please improve references with the Italian studies that provided detailed data about geochemical elaboration and application of techniques of spatial analysis along Italian coastal areas:
Vespasiano G., Cianflone G., Cannata C.B., Apollaro C., Dominici R. & De Rosa R. (2016): Analysis of groundwater pollution in the Sant’Eufemia Plain (Calabria – South Italy). Italian Journal of Engineering Geology and Environment. DOI: 10.4408/IJEGE.2016-02.O-01
Vespasiano G., Cianflone G., Romanazzi A., Apollaro C., Dominici R., Polemio M., De Rosa R. (2019). A multidisciplinary approach for sustainable management of a complex coastal plain: The case of Sibari Plain (Southern Italy). Marine and Petroleum Geology. https://doi.org/10.1016/j.marpetgeo.2019.06.031
P2/Area of Study: Geological and structural setting characterizing recharge areas and the portions of territory crossed by the tributaries should be added in this section. Apart from the anthropic contribution, the rocks are the main source of constituents in solution. I suggest improving the section with a schematic geo-structural map. Furthermore, in figure 1 should be added all the all possible sources of anthropogenic pollution.
P3/Data Sampling: I suggest reporting all sampling phases (detailed) in this section and avoid the references in other paragraphs. It would be worth briefly mentioning the sampling and analysis techniques of the different constituents elaborated.
P5/Results: To a better comprehension of the processes in act, it could be useful to add a “geochemical characterization” section. Preliminarily, authors can improve knowledge about processes by using binary diagrams (Cl vs. elements) to evaluate variation in the constituents ratios and speciation-saturation calculations to highlights oversaturation respect specific phases.
See the paper:
Apollaro, A. Caracausi, M. Paternoster, P. Randazzo, A. Aiuppa, R. De Rosa, I. Fuoco, G. Mongelli, F. Muto, E. Vanni, G. Vespasiano 2020. Fluid geochemistry in a low-enthalpy geothermal field along a sector of southern Apennines chain (Italy). Journal of Geochemical Exploration. https://doi.org/10.1016/j.gexplo.2020.106618.
Conclusions: In the section, the discussion of the importance of spatial analysis should be improved, which is only partially treated. Furthermore, in the discussions, mention is made of possible sources of both natural and anthropogenic pollution. These must be well described in the general description of the area.
Author Response
hydrology-940644– Revised Manuscript
RC = Reviewer’s Comment; AR = Authors’ Response
Reviewer #2:
RC: “The authors provide illustrate the potential application of techniques of spatial analysis and Geographic Information Systems (GIS) to categorize the distribution of temporal and spatial of water predictions characteristics to determine the water quality parameters of the Shatt Al-Arab River (SAA), Southern Iraq.
The manuscript Hydrology-940644 is well written and represents a valuable contribution to the literature. I believe this manuscript should be published after a major revision. The revision should include a better geological description followed by a schematic geological map to get an overview of the results obtained. Furthermore, the paper should be improved with a geochemical characterization.”
AR: The authors appreciated the reviewer acknowledgment of this manuscript. The authors made the required changes as suggested by the reviewers (see the revised manuscript).
RC: “P1-2/Introduction: Please improve references with the Italian studies that provided detailed data about geochemical elaboration and application of techniques of spatial analysis along Italian coastal areas:
Vespasiano G., Cianflone G., Cannata C.B., Apollaro C., Dominici R. & De Rosa R. (2016): Analysis of groundwater pollution in the Sant’Eufemia Plain (Calabria – South Italy). Italian Journal of Engineering Geology and Environment. DOI: 10.4408/IJEGE.2016-02.O-01
Vespasiano G., Cianflone G., Romanazzi A., Apollaro C., Dominici R., Polemio M., De Rosa R. (2019). A multidisciplinary approach for sustainable management of a complex coastal plain: The case of Sibari Plain (Southern Italy). Marine and Petroleum Geology. https://doi.org/10.1016/j.marpetgeo.2019.06.031”.
AR: The authors improved the references with the Italian studies that provided detailed data about geochemical elaboration and application of techniques of spatial analysis along Italian coastal areas. The authors cite these references as follows (see Introduction section in lines 87-102 in the revised manuscript):
“Furthermore, the analysis of geochemical and hydrogeological properties for water quality parameters were investigated by several researches [37-39]. Vespasiano et al. [37] investigated the aquifer pollution phenomena and influence of salt concentrations in the Sant’Eufemia plain, Italy. They investigated four main geochemical parameters and analyzed them by collecting 42 samples of streams and groundwater. Vespasiano et al. [37] found that high concentrations of calcium and sulfate suggested mixing processes among the thermal waters. The results also found that high concentration of potassium and nitrate can be attributed to anthropogenic activities. In 2019, Vespasiano et al. [38] integrated hydrogeological and geochemical approach using spatial analysis to investigate the conceptualization of plain groundwater system in Sibari coastal plain, Calabria, southern Italy. They found that the sodium, magnesium, chloride, and sulfate can be ascribed to seawater intrusion, while the potassium is considered the major pollutant of the shallow aquifer. Apollaro et al. [39] investigated chemical and isotopic features of two different types of waters: cold shallow and hypothermal waters, in the Lucane thermal area, southern Italy. They studied geochemical data to determine a geothermal reservoir temperature. They found that the rock deformation can increase the output of some geochemical that produced in minerals and rocks”.
RC: “P2/Area of Study: Geological and structural setting characterizing recharge areas and the portions of territory crossed by the tributaries should be added in this section. Apart from the anthropic contribution, the rocks are the main source of constituents in solution. I suggest improving the section with a schematic geo-structural map. Furthermore, in figure 1 should be added all the all possible sources of anthropogenic pollution.”
AR: The authors improved this section by added new Figure 2 (geological map) and added the following section about geological formation for the study area (see section 2.2 and Figure 2 in revised manuscript):
“2.2. Geological Formations
The study area is characterized by the fact that it is located within the Mesopotamian plain, which belongs to the quaternary model area with very large thickness in stony terms. Those sediments that represent the Mesopotamian plain are usually filled with gravel and sand. The upper part of the sequence is usually very stony monotonous, and is composed of flowing silt with a strong iolite mixture. The quaternary sediments are divided into Holocene and Pleistocene sediments over 100 meters thick, while those of Pleistocene rivers consist mainly of fine sand, clay, and silt [50].
The facial changes and vertical lithological variation are quite frequent in such fluvial deposits. The origin of these deposits is the Tigris and Euphrates flood plain system. The upper contact with the Holocene deposits was taken at the top of yellowish-brown clay or silty clay bed. This clay bed contains large gypsum crystals (Figure 2). It has often sharp contact with the overlying deposits. The Holocene deposits from horizontal diversity of surface sedimentary environments that mainly consist of fluviatile, lacustrine, Sabkhas, and marine [51]. The fluviatile deposits are derived from the Tigris, Euphrates, and Karun Rivers. These sediments are deposited in the floodplain and natural levees of SAA channels in both sides and consist dominantly of silty mud in the region that extends from Qurna to the south of Basra, whereas it changes into brown muddy sand from Siba up to the mouth of SAA at Arabian Gulf that reflecting the role of Karun River [50]. Lacustrine sediments are represented by marshes and lakes that flanked SAA from the north and northwest and consist of fine texture, light grey color, with darker organic intercalation. The lacustrine system of the lower Mesopotamian Plain is classified as active marshes, open lakes, and dry marshes [51]. The deposits of Sabkhas are situated between SAA and Khor Al-Zubair. They form super-tidal surfaces produced mostly by seaward progradation of the coastline [51].”
The authors also added all the possible sources of anthropogenic pollution in Figure 1 and added the following section:
“2.3 Pollution Sources of SAA
The household and sewage wastes are one of the most important sources of the pollution in SAA. This polluted water throws into the river microbes and organic matter that is harmful to public health when decomposed. The most prominent of these germs are dysentery and typhoid germs. The increase in household waste leads to an increase in salts that in turn leads to the growth of phytoplankton. This is caused an increase in aquatic algae. This aquatic alga requires the consumption of a large amount of dissolved oxygen in the river. Many materials from household waste settle and form the sludge bed, which covers most of the bottom of streams that flow into the SAA (Figure 1). In addition, industrial waste from the paper mill in northern Basra city and the fertilizer plant in southern Basra city are another source of pollution to SAA [45, 48]. Without any treatment, the southern region power station has negative impact on pollution of SAA by throwing hot water into the river. This hot water leads to a decrease in the amount of dissolved oxygen in SAA. In addition, the effect of chemical and organic fertilizers in the south of SAA led to an increase in aquatic algae. This also decreases the amount of oxygen dissolved in the river. The pesticide toxins is another pollutants that seeps from agricultural lands into irrigation water and then into drainage water and into river water. This influences also on river water quality system. This leads to the death of aquatic organisms, especially fish and birds [48].”
RC: “P3/Data Sampling: I suggest reporting all sampling phases (detailed) in this section and avoid the references in other paragraphs. It would be worth briefly mentioning the sampling and analysis techniques of the different constituents elaborated. “
AR: The authors reported all sampling phases (detailed) in “Data Sampling” section as follows:
“2.4. Data Sampling
Eleven sampling stations were selected through the SAA described previously within the area of study. The coordinates and locations of these stations are abstracted in Figure 1. The sampling station (Azer station) is located upstream of the river which can be considered as a reference station for other stations because it is far from the outfall of wastewater as shown in Figure 1. Samples were acquired periodically from the stations at the study site during the period from December 2018 to October 2019. The sampling was performed using the small boats belonging to the river police in Basra city and the boats for the fishermen. The samples were acquired from the central area of the river about 35 m away from the right or left bank of the river and at a depth of 9.0 m below the surface of the water. Using Manual Pull Plastic Manual Pump device, a water hose (15 m long), and a weight of iron of 2.0 kg installed at the end of the plastic hose, it is easy to examine into the depth mentioned and it's floating on the river's surface.
Water samples were collected in sealed plastic containers bottles of 1.5 liter capacity in sterile conditions. The sample was stabilized and analyzed within 24 hours to avoid potential changes due to environmental degradation of water. The data analyses were performed by considering all recommendations of standard methods of analysis in the collection, acquiring, transferring, and conservation of aquatic samples. A 500 ml of the sample for metallurgical analysis added to 5 ml of concertation HNO3 to be analyzed within one hour after sealing. This treatment was used to reduce the absorption of minerals on the walls of the container. This process was carried out four times each season. To measure the tidal movement of water in the river, about 55 x 1.5 liters of river water is packed in special and sealed in plastic containers. At the end of each day, the samples were sent to the laboratory for testing and measurements. The water quality parameters of TDS, TH, SO4, Cl, turbidity, Na, PO4, TOC, Cd2+, Cr3+, and Se were analyzed in the laboratory during the period commenced in December 2018 through October 2019. The Aqua Read GPS (Aqua meter, model: AM-200) was conducted to measure the TDS, pH, EC, turbidity, temperature, and salinity concentrations. The Spectrophotometer (Model: U-1500) was used to measure the SO4, PO4, and NO3.The Atomic absorption (AA-7000/AAC, Dual Atomizer system) was conducted to measure heavy metals elements.”
RC: “P5/Results: To a better comprehension of the processes in act, it could be useful to add a “geochemical characterization” section. Preliminarily, authors can improve knowledge about processes by using binary diagrams (Cl vs. elements) to evaluate variation in the constituents ratios and speciation-saturation calculations to highlights oversaturation respect specific phases.
See the paper:
Apollaro, A. Caracausi, M. Paternoster, P. Randazzo, A. Aiuppa, R. De Rosa, I. Fuoco, G. Mongelli, F. Muto, E. Vanni, G. Vespasiano 2020. Fluid geochemistry in a low-enthalpy geothermal field along a sector of southern Apennines chain (Italy). Journal of Geochemical Exploration. https://doi.org/10.1016/j.gexplo.2020.106618.”
AR: The authors added the new section “3.7. Geochemical Characterizations” and improved the knowledge by construction new TIS and binary diagrams (see new Figures 14 and 15) as follows:
“3.7. Geochemical Characterizations
The study of geochemical properties aims to facilitate the understanding and interpretation of all evolutionary trends, especially in surface water system, when they are interpreted in conjunction with maps of hydrochemical divisions and their distribution. Moreover, water chemistry is studied primarily by: (i) the correlation graph of SO4 vs. HCO3 + Cl, in which iso-salinity lines are drawn for reference (Figure 14), and (ii) triangular plots involving major cations and anions as reported by Vespasiano et al. [37]. Also, the SO4 versus HCO3 + Cl correlation scheme can recover the ratios between variants that lose information about the absolute concentration, that is, the mass of chemical components of interest indicates one kilogram of sulfate. As reported, salinity water composition has used to evaluate the presence of mixing processes between surface water and shallow and deep aquifers. Figure 14 highlights that SO4 and HCO3 + Cl are the main constituents of the aqueous solutions.
Figure 14 highlights another useful index for water classification called Ionic Salinity or Total Ionic Salinity (TIS). This index shows the sum of anion and cation total contents (expressed in mg/l). The values of Iso-TIS lines are reported in Figure 14 as sum of SO4 and Cl + HCO3. The samples of SAA waters fall into four groups: (i) less than 2000 mg/l, (ii) between 2000 and 3000 mg/l, (iii) between 3000 and 4000 mg/l, and (iv) between 4000 to 5000 mg/l. The most data are located between 2000 to 4000 mg/l. Even if these diagrams are not very suitable for the detection of possible mixing processes, it is possible to identify a mixing line between waters from the SAA sampled upstream of the river estuary with those of other water samples characterized by Mg-SO4 composition. The waters of the SAA are characterized by strong mixing and weak stratification, which shows the role of marine waters that penetrate into the SAA course in increasing the concentration of salts of river water along the water column.
Figures 15a and 15b highlight the relationships between the main solutes in the sampled of SAA waters using the two plots of Ca/(Ca+Mg) vs. HCO3/(HCO3+SO3) and Mg vs. SO4, respectively. The water chemistry interactions that take place between the waters of the SAA and the marine waters entering from the Arabian Gulf result from the interactions of water rocks during groundwater circulation in a system dominated by evaporating carbonate rocks (Figure 15a). Most of SAA waters fall below Magnesite tie-line, while some of them fall below the Dolomite tie-line. This is indicated that the dissolution of carbonate rocks is mainly Dolomite and Magnesite. In contrast, Magnesium carbonate seems to react with Shatt Al-Arab waters lithologies (Figure 15a).
Usually, Epsomite (a hydrous of magnesium sulfate) dissolution leads to an increase in SO4 and Mg contents in the groundwater with Mg/SO4 ratios equal to 1. However, in the Mg vs. SO4 diagram (Figure 15b), the SAA waters are distributed below the Epsomite dissolution line. Most water samples have Mg/SO4 ratios of less than 1, excluding two samples. The deviation from the Epsomite dissolution line could be linked to either (i) a decrease in magnesium concentrations due to less magnesite rocks dissolution, or (ii) an increase in sulfate contents (Figure 15b). The Na-Cl plot (Figure 15c) shows that most of the Na-Cl water samples distributed below the Na-Cl dilution line. Most water samples of SAA have Na/Cl ratios of less than 1, excluding one sample. The trend line of Na-Cl plot deviated from the Na-Cl dilution line, with a negative coefficient of 140, a slope of 1.67, and a correlation coefficient R2 of 0.98.”
RC: “Conclusions: In the section, the discussion of the importance of spatial analysis should be improved, which is only partially treated. Furthermore, in the discussions, mention is made of possible sources of both natural and anthropogenic pollution. These must be well described in the general description of the area. “
AR: The authors improved the spatial analyses of some important parameters in “Conclusions” section as follows:
“The spatial distribution of TDS found that high concentrations of TDS were observed in the central of SAA during winter 2018. The TDS increased toward very south of SAA before entrance to the Arabian Gulf, especially in autumn 2019. During winter 2018, an increase in sulfate concentrations along the SAA waterway was observed in the sulfate spatial distribution. This increase gradually continued to the south of SAA. During summer 2019, a uniform spatial distribution of sulfate concentrations was observed in all monitoring stations on the SAA, excluding for that in Al-Hartha and Al-Karma stations. Furthermore, the analyses of geochemical properties showed that SAA waters mainly from the dissolution of carbonate rocks. Most of SAA water samples are distributed below the Epsomite dissolution line and the Na-Cl dilution line.”
The authors described well all sources of natural and anthropogenic pollution in general description of the study area (see Figure 1 and section 2.3).
Author Response File: Author Response.docx
Reviewer 3 Report
The manuscript, presenting an intersting analysis on the evaluation of water quality paramters of the Shatt Al-Arab River by using a spatial analysis, is in line with the aims of the journal. The manuscript is well written and the structure balanced, as well as the English style and language needs to be only litlle revised. For this reason this reviewer suggests a minor revision of the manuscript. Below some suggestions.
In the introduction section the authors could better connect some concepts. For example, in line 60, when they start directly to explain the GIS software, a connection with the previous lines, as a little introduction on the potentiality of use of the GIS in the specific field, before talking on the software it would be necessary. In addition, the authors should better specified the novelty of their study than the previous ones, and how it can fill the scientific gap.
In Material and Methods section, the authors could add more details on the type of sampling stations, the devices accurancy, data acquisition system, and so on.
This reviewer also suggets to increase the quality of the figures.
Author Response
hydrology-940644– Revised Manuscript
RC = Reviewer’s Comment; AR = Authors’ Response
Reviewer #3:
RC: “The manuscript, presenting an intersting analysis on the evaluation of water quality paramters of the Shatt Al-Arab River by using a spatial analysis, is in line with the aims of the journal. The manuscript is well written and the structure balanced, as well as the English style and language needs to be only litlle revised. For this reason this reviewer suggests a minor revision of the manuscript. Below some suggestions.”
AR: The authors appreciated the reviewer acknowledgment of this manuscript. The authors made the required changes as suggested. The authors checked the English language and made the required changes (see the revised manuscript).
RC: “In the introduction section the authors could better connect some concepts. For example, in line 60, when they start directly to explain the GIS software, a connection with the previous lines, as a little introduction on the potentiality of use of the GIS in the specific field, before talking on the software it would be necessary. In addition, the authors should better specified the novelty of their study than the previous ones, and how it can fill the scientific gap.”
AR: The authors agreed with reviewer comment and connected the paragraph of GIS software with previous sections as follows (see Introduction section in lines 58-61 in revised manuscript):
“Due to the enormous development in various fields of science, it may become necessary to adopt a familiar technique to study water environments. Researchers have used different methods to express water resource quality. One of the most significant techniques is the Geographical Information System (GIS) [19].”
The authors also showed the novelty of this work as follows (see Introduction section in lines 109-115 in revised manuscript):
“Due to the huge damage to the water quality which could occur as a result of the salt level increase, wide concern has been raised about this issue among Iraqi people, especially, those who are living in the south of Iraq [44]. Shatt Al-Arab River in Basra city, is an example of salinity problems in southern Iraq due to saline water coming back from Arabian Gulf and due to low flow rates from both Tigris and Euphrates Rivers. In addition, pollutants in this river were increased due to wastewater discharge from pollution resources that located along riverbank of SAA. There is no study till now that applied spatial analysis using Kriging interpolation method, and adopted geochemical analysis to analyze water quality parameters of SAA.”
RC: “In Material and Methods section, the authors could add more details on the type of sampling stations, the devices accurancy, data acquisition system, and so on.”
AR: The authors added more details in “Data Sampling” section as follows:
“2.4. Data Sampling
Eleven sampling stations were selected through the SAA described previously within the area of study. The coordinates and locations of these stations are abstracted in Figure 1. The sampling station (Azer station) is located upstream of the river which can be considered as a reference station for other stations because it is far from the outfall of wastewater as shown in Figure 1. Samples were acquired periodically from the stations at the study site during the period from December 2018 to October 2019. The sampling was performed using the small boats belonging to the river police in Basra city and the boats for the fishermen. The samples were acquired from the central area of the river about 35 m away from the right or left bank of the river and at a depth of 9.0 m below the surface of the water. Using Manual Pull Plastic Manual Pump device, a water hose (15 m long), and a weight of iron of 2.0 kg installed at the end of the plastic hose, it is easy to examine into the depth mentioned and it's floating on the river's surface.
Water samples were collected in sealed plastic containers bottles of 1.5 liter capacity in sterile conditions. The sample was stabilized and analyzed within 24 hours to avoid potential changes due to environmental degradation of water. The data analyses were performed by considering all recommendations of standard methods of analysis in the collection, acquiring, transferring, and conservation of aquatic samples. A 500 ml of the sample for metallurgical analysis added to 5 ml of concertation HNO3 to be analyzed within one hour after sealing. This treatment was used to reduce the absorption of minerals on the walls of the container. This process was carried out four times each season. To measure the tidal movement of water in the river, about 55 x 1.5 liters of river water is packed in special and sealed in plastic containers. At the end of each day, the samples were sent to the laboratory for testing and measurements. The water quality parameters of TDS, TH, SO4, Cl, turbidity, Na, PO4, TOC, Cd2+, Cr3+, and Se were analyzed in the laboratory during the period commenced in December 2018 through October 2019. The Aqua Read GPS (Aqua meter, model: AM-200) was conducted to measure the TDS, pH, EC, turbidity, temperature, and salinity concentrations. The Spectrophotometer (Model: U-1500) was used to measure the SO4, PO4, and NO3.The Atomic absorption (AA-7000/AAC, Dual Atomizer system) was conducted to measure heavy metals elements.”
RC: “This reviewer also suggest to increase the quality of the figures. “
AR: The authors adjusted all the figures with high resolutions (all figures now have 300 DPI resolutions). The authors also adjusted Figure 1 based on this comment and other reviewer’s comments (Please, see the Figures in the revised manuscript).
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Figure 1 continues to show poor quality, like figure 2 (this can be seen in the letters of the legend) and 13.
Reference 58 is not cited.
Comments for author File: Comments.docx
Author Response
hydrology-940644– Second Revised Manuscript
RC = Reviewer’s Comment; AR = Authors’ Response
Reviewer #1:
RC: “The work is very good; but it needs minor revision before publication.
According to my point of view, figure 1 continues to show poor quality, like figure 2 (this can be seen in the letters of the legend) and 13. The image is not very sharp. But I leave it to the editor's consideration.”
AR: The authors appreciated the reviewer acknowledgment of this manuscript. The authors made the required changes as suggested by the reviewer (see the second revised manuscript).
The authors adjusted Figures 1, 2, and 3 to have more quality and made the legends more readable (Please, see these figures in the second revised manuscript). The authors also uploaded all figures through the online system with a minimum resolution of 300 DPI.
RC: “Reference 58 is not cited.”
AR: The authors cited the Reference 58 (see lines 282-286, in the second revised manuscript).
Author Response File: Author Response.docx
