The Mechanism and Regularities of Ion Runoff Formation in the Ob River (Western Siberia) under the Influence of Its Tributaries and Underground Feeding
Round 1
Reviewer 1 Report
General comments
The research fits the scope of the journal and special issue, and is presented with robust graphs. Issues are present and all the specific comments need to be addressed before publication
Specific comments
Line 26. Add a general statement on the importance of surface – groundwater interaction in basins with rivers. Here, list of relevant literature on the topic for integration
- Medici, G. and Langman, J.B., 2022. Pathways and Estimate of Aquifer Recharge in a Flood Basalt Terrain; A Review from the South Fork Palouse River Basin (Columbia River Plateau, USA). Sustainability, 14(18), p.11349.
- Kalbus, E., Reinstorf, F. and Schirmer, M., 2006. Measuring methods for groundwater–surface water interactions: a review. Hydrology and Earth System Sciences, 10(6), pp.873-887.
Line 26-95. No information on surface – groundwater interactions from international literature. Please, add in the new version of the paper
Line 95. Cleary state the aim of your research, and the two to three specific objectives by using numbers (e.g., i, ii, and iii)
Line 109. Define the acronym Total Dissolved Solids (TDS)
Line 228. Dicarbonate or bicarbonate? Please, check
Lines 295-297. Remove the note or integrate this part in the paragraph
Line 357. What you mean by “in absolute terms”? Please add more detail when you discuss the runoff
Lines 410-414. The sentence is too long. Please, split it in two parts
Line 424. No references in the conclusions. Please, change it
Line 430. Funding information should not be part of the conclusion
Line 437. Add the relevant references suggested above
Figure and tables
Figure 2. No faults in the section. Justify in the introduction for researchers not familiar with the study site
Figure 3. Add letters a, b, and c to the figures
Figures 8 and 9. Increase the size of the figures on the axes
Minor editing of English language is required
Author Response
Authors Reply to the Reviewer Report
Dear Reviewer!
We sincerely thank you for your careful reading and positive evaluation of our manuscript, as well as your constructive correction and valuable comments. We have accepted your comments and edited the text in accordance with them. Please refer to the revised manuscript submitted for further consideration.
Specific comments
Line 26. Add a general statement on the importance of surface – groundwater interaction in basins with rivers. Here, list of relevant literature on the topic for integration
Reply: relevant publications added.
- Medici, G. and Langman, J.B., 2022. Pathways and Estimate of Aquifer Recharge in a Flood Basalt Terrain; A Review from the South Fork Palouse River Basin (Columbia River Plateau, USA). Sustainability, 14(18), p.11349.
- Kalbus, E., Reinstorf, F. and Schirmer, M., 2006. Measuring methods for groundwater–surface water interactions: a review. Hydrology and Earth System Sciences, 10(6), pp.873-887.
Line 26-95. No information on surface – groundwater interactions from international literature. Please, add in the new version of the paper
Reply: added.
Line 95. Cleary state the aim of your research, and the two to three specific objectives by using numbers (e.g., i, ii, and iii)
Reply: added.
Line 109. Define the acronym Total Dissolved Solids (TDS)
Reply: added.
Line 228. Dicarbonate or bicarbonate? Please, check
Reply: changed.
Lines 295-297. Remove the note or integrate this part in the paragraph
Reply: moved to text.
Line 357. What you mean by “in absolute terms”? Please add more detail when you discuss the runoff
Reply: added; for example, in tons per year, not tons per second per square kilometer
Lines 410-414. The sentence is too long. Please, split it in two parts
Reply: changed.
Line 424. No references in the conclusions. Please, change it
Reply: changed
Line 430. Funding information should not be part of the conclusion
Reply: removed.
Line 437. Add the relevant references suggested above
Reply: relevant references added.
Figures and tables
Figure 2. No faults in the section. Justify in the introduction for researchers not familiar with the study site
Reply: Faults are not shown because Figure 2 is a diagram. Attracting additional material, taking into account the necessary explanations, will greatly increase the volume of the article, but will not add new meaning. More detailed information is given in works on geology and hydrogeology, listed in References [6-8].
Figure 3. Add letters a, b, and c to the figures Figures 8 and 9. Increase the size of the figures on the axes
Reply: added.
Figures 8 and 9. Increase the size of the figures on the axes
Reply: Increased
Reviewer 2 Report
Ln 14 – by underground do you mean groundwater or any water above and/or below the water table?
Figure 1 provides a good view of the watershed with its various rivers. For readers not very familiar with the region it would be nice to have a figure that also shows the various landscapes you present such as the taiga, steppe, forest steppe, etc.
Ln 45- it would be helpful to provide the southern extent of present-day permafrost on a figure.
Ln 53- the western boundary of the Ob basin are the Ural mountains?
Ln 57 – The city of Salekhard does not show up on the map so it is difficult to visualize the WSAB.
Figure 2 – why is this section of the Katun River Basin selected to show the geologic under-pinings of the watershed? Also I do not see the line of Hr(Kt) represented on the graph.
Ln 86 – the introduction the region is excellent but could use some additional graphics as suggested above including helping the reader clearly understand the distribution of the socio-economic activities of the area. A clearer picture will help the reader visualize the sources of the various ions that have been monitored throughout the watershed and relate those to both landscape positions and distribution of human activities. For example it is still not clear to me where the majority of the population lives in the forest-steppe region because it is not clear to someone not familiar with the region exactly where that is – a bit more clarity in locations based on the map would be helpful.
Ln 97 – including the names of the authors instead of just the location of the references would be helpful.
Ln 130 – where on the two rivers are the cities of Srostki and Biysk located? Are they in the headwaters of the two channels or near their confluence with each other?
Ln 150 – How was actual ground water input measured. Were there any monitoring wells along the reaches of the various stream sections?
Ln 225 – I am not well versed in the analysis of the data that you collected so am not able to comment. It seems to me that the approach is well founded – Table 1 provides a good summary of locations and data that was collected at each station. It is not clear to me if actual groundwater data was collected.
Ln 240 – where is the high Cl in the forest steppe coming from? Why is this saline water used in the pressure maintenance system in facilities for production of hydrocarbons under ground?
Ln 252 – are most of the swampy areas you are describing bog or fens with bogs having little flow through them and fens having flow input and output through the system, the latter usually with higher pH values?
Ln 268 – is the decrease in consumption of aquatic organisms an anthropomorphic function or a function of other organisms in the wetland systems?
Ln 280 – what is meant by modern swamp formation – is this a natural process or the result of human activity and if the latter, how and why?
Ln 283 – it would be of interest to the reader to know what the drinking water standards are in your country.
Ln 285 – in the table NO3 is indicated but in the text it is NO2?
Ln 292 – it would be interest to the reader why there are significant differences between right bank and left bank inputs in a seemingly natural system.
Ln 325 – the downstream impacts on TDS from the Irtysh river is amazing.
Conclusion section – this is an excellent paper describing the changes in ion concentrations in different reaches of the Ob river system that runs through a number of different topographic and plant communities. The data is well organized and presented but for those of us not familiar with the taiga and various tundra zones it would be helpful if the authors provide a bit more description of why these different zones provide the different input. The reader is assuming that there is relatively little anthropogenic impact on the different ion concentrations of the different taiga and tundra zone so it would be helpful to the reader if the authors provide a little more information on the reasons for the differences. Differences in topography are suggested but what role do the different plant communities have in trapping and holding various ions, etc.
Overall summary;
This is an excellent paper, well and clearly written with good graphics and detailed descriptions of methods and materials. The paper provides ecologists and hydrologists with an intriguing view of changes in water chemistry in a relatively pristine river systems that flows through a range of geological landscape positions and plant communities. It is an excellent demonstration of how long term data can be used to help us understand what is going on in natural systems. This is a good base-line paper that can be repeated over the next decade or more to show the impacts of climate change on the release of nutrients and carbon to the system as the decomposition of the tundra and taiga is accelerated.
Author Response
Dear Reviewer!
We are grateful to you for your attentively reading of our manuscript and its high appreciation. According to your comments we have added some information on the Ob River basin natural conditions on Figure 1 and in the text of the manuscript and detailed Author's responses to the comments.
Ln 14 – by underground do you mean groundwater or any water above and/or below the water table?
Reply: The underground component of the runoff is considered, which usually represents the waters of the upper hydrogeodynamic zone. This is up to about 100 -200 m. In this area on the plain, these are mainly water deposits of the Quaternary and Palenogene age. In the mountainous regions the situation is more complicated. Explanations are given in the text and table 2.
Figure 1 provides a good view of the watershed with its various rivers. For readers not very familiar with the region it would be nice to have a figure that also shows the various landscapes you present such as the taiga, steppe, forest steppe, etc.
Reply: added.
Ln 45- it would be helpful to provide the southern extent of present-day permafrost on a figure.
Reply: added.
Ln 53 - the western boundary of the Ob basin are the Ural mountains?
Reply: added. The main watershed of the Urals is the western boundary of the Ob basin.
Ln 57 – The city of Salekhard does not show up on the map so it is difficult to visualize the WSAB.
Reply: Salekhard, Srostki, Biysk and most other settlements have a small area and population. For the conditions of Siberia, they are important, but it is difficult to show them on the map. For more information, see Shiklomanov et al., 2013 (with reference to the network of Arctic stations).
Figure 2 – why is this section of the Katun River Basin selected to show the geologic under-pinings of the watershed? Also I do not see the line of Hr(Kt) represented on the graph.
Reply: The Katun river basin represents the main part of the northern Altai within the borders of the Russian Federation. The flow of this river most of all characterizes the conditions of Altai. The Biya River flows out of Lake Teletskoye. The flow of this river is regulated by this lake. Therefore, the conditions in the Biya river basin are specific and do not reflect the basic conditions of Altai.
Ln 86 – the introduction the region is excellent but could use some additional graphics as suggested above including helping the reader clearly understand the distribution of the socio-economic activities of the area. A clearer picture will help the reader visualize the sources of the various ions that have been monitored throughout the watershed and relate those to both landscape positions and distribution of human activities. For example it is still not clear to me where the majority of the population lives in the forest-steppe region because it is not clear to someone not familiar with the region exactly where that is – a bit more clarity in locations based on the map would be helpful.
Reply: We understand that there is not enough information about the socio-economic conditions in Siberia. But adding this information threatens to change the direction of the whole work. The population of all Siberia (east of the Urals) is a little over 12 million. The main part of the population lives in the west (eastern slopes of the Urals) and south (Novosibirsk region, Altai Territory, Kemerovo region) of the Ob River basin. This corresponds to the rivers Tobol, Tura, Tom and the Ob itself near Novosibirsk and Barnaul. Swamps are common in the north. This is where oil and gas are produced. Quantitatively, the influence of anthropogenic factors is expressed in the characteristics of the runoff of tributaries (Table 2). The meaning of the work is precisely to show a general change in the absence of data on specific effects.
Some additional information on the natural and socio-economic conditions in the study area might be found in: Zemtsov, V.A., Paromov, V.V., Kopysov, S.G., Kouraev, A.V., Negrul, S.V. Hydrological risks in Western Siberia under the changing climate and anthropogenic influences conditions // International Journal of Environmental Studies. 2014. 71 (5). pp. 611-617. DOI: http://dx.doi.org/10.1080/00207233.2014.942530
Ln 97 – including the names of the authors instead of just the location of the references would be helpful.
Reply: The numbering of the lines is slightly inconsistent with the version of the article. Therefore, we apologize if the layers did not quite understand the question. If we are talking about references 8, 9, 10 (according to the comments of another reviewer, the list was expanded), then these are the authors of the article - Zemtsov Valery and Savichev Oleg. Probably, it would be indiscreet to refer to oneself. But we believe that we have the most complete picture of the state of the Ob River basin as a whole.
Ln 130 – where on the two rivers are the cities of Srostki and Biysk located? Are they in the headwaters of the two channels or near their confluence with each other?
Reply: As mentioned above, Srostki (especially) and Biysk are small settlements. They are located almost in the mouth areas of the Katun and Biya rivers.
Ln 150 – How was actual ground water input measured. Were there any monitoring wells along the reaches of the various stream sections?
Reply: When estimating the underground component of the runoff, we used observational data from regime wells. Unfortunately, there are few such wells. Information about them is given in the work of Savichev, Guseva and Moiseeva in 2022 and the monograph by Shiklomanov et al. in 2013. The main part of the calculations was carried out according to the method using river runoff measurements data – river runoff separation, or hydrograph separation (formula 11) in the manuscript.
Ln 225 – I am not well versed in the analysis of the data that you collected so am not able to comment. It seems to me that the approach is well founded – Table 1 provides a good summary of locations and data that was collected at each station. It is not clear to me if actual groundwater data was collected.
Reply: The calculations were made on the basis of long-term observations on rivers and underground waters (in the second case, there are much fewer data). All these initial data in one form or another are published in the works listed in the references, including the monograph by Shiklomanov et al., 2013. What is new is the integration of all data and assessment of the total change in the ionic flow of the Ob River from the confluence of the Biya and Katun rivers to the Gulf of Ob. We are not aware of such a work.
Ln 240 – where is the high Cl in the forest steppe coming from? Why is this saline water used in the pressure maintenance system in facilities for production of hydrocarbons under ground?
Reply: Chlorides are present in increased amounts in river and groundwater in the steppe and forest-steppe zones. This is due to the evaporation mechanism of the formation of the chemical composition of waters. There are also many chlorides in groundwater in deep horizons (Mesozoic and Paleozoic deposits) on the plain. This is due to slow water exchange and an increase in the time of interaction between water and rocks. We have shown in the article that the structure of the basin suggests the features of the accumulation of substances in groundwater when the mountains change to the plain. This is new and debatable. We would like this point to be published and discussed if possible. To continue it will require new research with a large amount of complex and expensive work to drill wells. Relief effects are also possible. In most cases, it is limited to sections of 8-10 kilometers. This information is given in references to the authors' works.
Ln 252 – are most of the swampy areas you are describing bog or fens with bogs having little flow through them and fens having flow input and output through the system, the latter usually with higher pH values?
Reply: Various types of swamps are common in western Siberia. In the north there are polygonal and hilly swamps. In many cases, these are inherited swamps from warmer periods of the Holocene. In the taiga zone, the main part of modern swamps with an average depth of about 4.5 meters. On the watersheds, raised and transitional bogs with predominantly atmospheric water and mineral nutrition are common, and in the river valleys there are many lowland fens and bogs connected to groundwater. The peat deposit has a two-layer structure. Horizontal water movement is usually only in the upper layer of 0.2-0.7 meters. The authors believe that low-lying swamps in river valleys have the greatest impact on rivers. The question of the relationship between marsh and groundwater is controversial. The authors are currently preparing a number of publications. Some results are published, for example in Applied Geochemistry in 2020 (Savichev O., Soldatova E., Rudmin M., Mazurov A. Geochemical barriers in oligotrophic peat bog (Western Siberia) // Applied Geochemistry. - 2020. - 113. 104519. p. 1-11. https://doi.org/10.1016/j.apgeochem.2019.104519. Rudmin M., Ruban A., Savichev O., Mazurov A., Dauletova A., and Savinova O. Authigenic and Detrital Minerals in Peat Environment of Vasyugan Swamp, Western Siberia // Minerals 2018, 8, 500. P. 1-13; doi:10.3390/min8110500. www.mdpi.com/journal/minerals. Eckstein Yoram, Savichev Oleg G., Pasechnik Elena Yu. Two decades of trends in ground water chemical composition in The Great Vasyugan Mire, Western Siberia, Russia // Environmental Earth Sciences, 2015, N 1, pp. 3-15. DOI 10.1007/s12665-014-3908-z.).
Ln 268 – is the decrease in consumption of aquatic organisms an anthropomorphic function or a function of other organisms in the wetland systems? + Ln 280 – what is meant by modern swamp formation – is this a natural process or the result of human activity and if the latter, how and why?
Reply: Currently, swamps in the southern taiga are growing at a rate of about 1 mm per year. There are a number of works on this subject, including the use of isotopes. The average depth of the swamps is about 4.5 meters. The swamps originated in parts about 5,000 years ago. Prior to that (15-12 thousand years ago), the territory of the plain and mountains was covered with glaciers. This is a debatable issue that the authors would not like to consider in the article. The bogging process is certainly natural. Relatively high precipitation at low temperatures (and evaporation) plus little infiltration and flat topography. The anthropogenic influence of people is local. For example, flow delays during the construction of roads to oil production facilities. But this is all within the framework of natural swamping. Almost the entire flat part of the taiga zone is a complex of swamps with a depth of 0.5 to 11 meters. There are two mechanisms for this. The first mechanism is classical. The lake is eutrophicated and turns into a swamp. The second mechanism is associated with the advance of swamps directly on the forest.
Ln 283 – it would be of interest to the reader to know what the drinking water standards are in your country.
Reply: There is a link in the bibliography. Nitrates 40 mg/l, nitrites - 0.08 mg/l. Water quality is normalized for drinking and fisheries water use. Compared to World Health Organization standards, standards are often more stringent. But this is not good for people. The issue is highly debatable: State Standard. Working Document GOST 27065–86. Water quality. Terms and definitions. Standart, Moscow, 2003; 9 p (in Russian)
Ln 285 – in the table NO3 is indicated but in the text it is NO2?
Reply: Not all data is shown in the table due to space limitations. Mostly those that were used in the analysis of the impact of groundwater and inflows were left. Nitrites are unstable, but there are relatively many of them during the transformation of organic matter in swamp waters and drains. A more complete list of substances is given in the works of the authors in the system www.elibrary.ru and on the website of the Tomsk Polytechnic University (library and page Savichev).
Ln 292 – it would be interest to the reader why there are significant differences between right bank and left bank inputs in a seemingly natural system.
Reply: The left bank of the Ob River in the Mesozoic and Paleogene was the bottom of the sea, and the right bank was the shore of this sea. The question is far beyond the scope of the article. But it is reflected in the literature specified in the article. Each aspect of this issue causes very strong discussions both directly in the Ob river basin and in the neighboring region of Central Siberia (traps). The authors would not like to get involved in this discussion.
Ln 325 – the downstream impacts on TDS from the Irtysh river is amazing.
Reply: In general, throughout the article there are many references to very different problems. That is why we would like to publish this material as a basis for further research. The Irtysh River is actually a separate region with conditions that are very different from conditions in other areas. But there are a lot of such cases inside the Ob river basin itself. The article presents itself as an attempt to see the problem as a whole. We understand that many questions remain. But you have to raise them somehow. At the same time, we are confident that the calculation results reflect reality as accurately as possible with existing observations.
Conclusion section – this is an excellent paper describing the changes in ion concentrations in different reaches of the Ob river system that runs through a number of different topographic and plant communities. The data is well organized and presented but for those of us not familiar with the taiga and various tundra zones it would be helpful if the authors provide a bit more description of why these different zones provide the different input. The reader is assuming that there is relatively little anthropogenic impact on the different ion concentrations of the different taiga and tundra zone so it would be helpful to the reader if the authors provide a little more information on the reasons for the differences. Differences in topography are suggested but what role do the different plant communities have in trapping and holding various ions, etc.
Conclusion section – this is an excellent paper describing the changes in ion concentrations in different reaches of the Ob river system that runs through a number of different topographic and plant communities. The data is well organized and presented but for those of us not familiar with the taiga and various tundra zones it would be helpful if the authors provide a bit more description of why these different zones provide the different input. The reader is assuming that there is relatively little anthropogenic impact on the different ion concentrations of the different taiga and tundra zone so it would be helpful to the reader if the authors provide a little more information on the reasons for the differences. Differences in topography are suggested but what role do the different plant communities have in trapping and holding various ions, etc.
Reply: the purpose of this study is a quantitative assessment of the conditions for the interaction of the Ob River with its main tributaries and groundwater in the process of formation of the ion runoff from a confluence of the Biya and Katun rivers to the Gulf of Ob. As it seems to the authors, we have quantitatively detected and studied the mechanism and regularities of ion runoff formation at the big river basin scale. More details would be investigated in separate publications.
Overall summary;
This is an excellent paper, well and clearly written with good graphics and detailed descriptions of methods and materials. The paper provides ecologists and hydrologists with an intriguing view of changes in water chemistry in a relatively pristine river systems that flows through a range of geological landscape positions and plant communities. It is an excellent demonstration of how long term data can be used to help us understand what is going on in natural systems. This is a good base-line paper that can be repeated over the next decade or more to show the impacts of climate change on the release of nutrients and carbon to the system as the decomposition of the tundra and taiga is accelerated.
