Hydrological Responses to Climate and Land Use Changes in a Watershed of the Loess Plateau, China
Round 1
Reviewer 1 Report
This is a very challenging manuscript to follow. While the main idea is quite simple (i.e., hydrological modelling using climate and land-use scenarios), the way that the authors connect the facts involved is a bit complicated. The study seems interesting but the authors need to work more in the flow of the manuscript, otherwise, it looks like a patchwork of random things.
For example, the end of the introduction there a long list of objectives and tasks that the study is trying to achieve, but an overview is still missing. What is the hypothesis behind it?
There are results in the methodology and these sections should be separated from each other.
The language also does not help sometimes, it surely needs some revision in that aspect.
Author Response
DETAILED RESPONSE
We are grateful to reviewers for their insightful review. The provided suggestions and comments have contributed substantially to improving the paper. Accordingly, we have made efforts to revise the manuscript and highlighted the changes in the revised manuscript, with the details explained as follows:
RESPONSES TO REVIEWER 1#’S COMMENTS
RESPONSE: We very much appreciate the reviewer for the positive response to the manuscript, and we also consider the provided suggestions to be very important and helpful for improving our manuscript. Accordingly, we have made careful efforts to revise it.
SPECIFIC COMMENT:
Point #1
COMMENT: For example, the end of the introduction there a long list of objectives and tasks that the study is trying to achieve, but an overview is still missing. What is the hypothesis behind it?
RESPONSE: We deeply appreciate the reviewer’s careful review. We have modified the presentation of this sentence. (Page 2, Lines 81-83):
Study of streamflow variation of the upper reaches of Beiluo River basin and hydrological responses to potential climate variability and land use change is important for sustainable utilization of water resources and local ecological preservation. Therefore, the main tasks of this research include the following: a) a CA-Markov model will be advanced for facilitating an effective assessment of potential impacts of land use changes, b) SWAT will be applied, calibrated and validated to simulate river runoff, c) three scenarios including the impacts of climate and land use changes and the combined impacts of climate and land use changes will be established and analysed, and d) SWAT is used to simulate three scenarios to evaluate the future impacts of climate and land use changes on water balance.
Point #2
COMMENT: There are results in the methodology and these sections should be separated from each other.
RESPONSE: We deeply appreciate the reviewer’s careful review and are regretful for the unclear description. We have moved these parts to the results section. (Page 7-9, Lines 205-237):
Point #3
COMMENT: The language also does not help sometimes, it surely needs some revision in that aspect.
RESPONSE: We very much appreciate the reviewer’s concern and careful review, and We have corrected the grammatical errors of the entire article. The entire article has been modified by the language company of American Journal Experts.
Reviewer 2 Report
This study investigated the individual and combined impacts of future LULC and climate 446 changes on water balance in the upper reaches of the Beiluo River basin on the Loess Plateau of China.
In general i read the paper with interest and accept the methodoologu used by authors. Only minor remarks stated as below:
In line 39 authors said: „These two factors are causing…” since before they said about many factors it is not clear which two they consider to be the most important. Please rewrite it.
In line 54-55 “These methods would require long-time series of observational data and lack physical mechanisms” I know what authors mean but I think is rather improper to “require a lack” please rephrase it.
Line 137 -138 “In this research, three different scenarios were established to predict the combined and individual potential impacts.” I not quite clear what are these scenarios at this point. I may miss something in previous chapter, but it seems like maybe not bad idea to say specifically here what scenarios are consider in the study
Please change font on flowchart shown in Figure 2. It is very difficult to read.
Figure 4. it is important to se clearly the comparison of observed and simulated values. In your plot rainfall covers the runoff values at two peaks 1992 and 1994, please change it to see clearly the comparison.
Author Response
DETAILED RESPONSE
We are grateful to reviewers for their insightful review. The provided suggestions and comments have contributed substantially to improving the paper. Accordingly, we have made efforts to revise the manuscript and highlighted the changes in the revised manuscript, with the details explained as follows:
RESPONSES TO REVIEWER 2#’S COMMENTS
RESPONSE: We very much appreciate the reviewer for the positive response to the manuscript, and we also consider the provided suggestions to be very important and helpful for improving our manuscript. Accordingly, we have made careful efforts to revise it.
SPECIFIC COMMENT:
Point #1
COMMENT: In line 39 authors said: „These two factors are causing…” since before they said about many factors it is not clear which two they consider to be the most important. Please rewrite it.
RESPONSE: We deeply appreciate the reviewer’s careful review. We have modified the presentation of this sentence. (Page 1, Lines 36-37):
Climate and land use are two important factors causing combined effects on the hydrological cycles and associated water resource systems in specific watersheds.
Point #2
COMMENT: In line 54-55 “These methods would require long-time series of observational data and lack physical mechanisms” I know what authors mean but I think is rather improper to “require a lack” please rephrase it.
RESPONSE: We deeply appreciate the reviewer’s careful review and are regretful for the unclear description. We have modified the presentation of this sentence. (Page 2, Lines 50-51):
These methods would need long-time series of observational data and lack of physical mechanisms (Li et al., 2009).
Point #3
COMMENT: Line 137 -138 “In this research, three different scenarios were established to predict the combined and individual potential impacts.” I not quite clear what are these scenarios at this point. I may miss something in previous chapter, but it seems like maybe not bad idea to say specifically here what scenarios are consider in the study.
RESPONSE: We very much appreciate the reviewer’s concern and careful review, and are regretful for the unclear description. We have modified the presentation of this sentence. (Page 4, Lines 128-130):
In this research, three different scenarios including only climate change, only land use change and combined climate and land use change were established to predict the individual and combined potential impacts on hydrological processes.
Point #4
COMMENT: Please change font on flowchart shown in Figure 2. It is very difficult to read.
RESPONSE: We very much appreciate the reviewer’s concern and careful review, and We have modified the font on flowchart shown in Figure 2.
Point #5
COMMENT: It is important to see clearly the comparison of observed and simulated values. In your plot rainfall covers the runoff values at two peaks 1992 and 1994, please change it to see clearly the comparison.
RESPONSE: We really appreciate the reviewer’s concern and careful review, and We have modified the figure to see clearly the comparison.
Author Response File: 
Author Response.pdf
Round 2
Reviewer 1 Report
The manuscript has improved in critical parts and in my opinion is almost ready to be published if the authors do not overlook important aspects:
a) The end of the introduction is still poor. The authors just added an overall and vague statement. The study needs a major aim/hypothesis;
b) Taking (a) into account, I would like to suggest the reference Lamparter et al. (2018, DOI: 10.1007/s10113-016-1015-2). I normally do not like to suggest references, but this one was a pioneer in the use of SWAT (the same model the authors use) with land-use and climate changes and the authors do not cite it. They could use at least as inspiration to make final changes;
c) Please include the coefficients used to assess in each figure you compare observed and simulated, and please also include coordinates in every figure you show maps;
d) I do believe that the first version of the manuscript went through English editing, as the authors say, but there are many sentences that do look weird. You only need to read the abstract to notice it.
Author Response
DETAILED RESPONSE
We are grateful to reviewers for their insightful review. The provided suggestions and comments have contributed substantially to improving the paper. Accordingly, we have made efforts to revise the manuscript and highlighted the changes in the revised manuscript, with the details explained as follows:
RESPONSES TO REVIEWER 1#’S COMMENTS
RESPONSE: We very much appreciate the reviewer for the positive response to the manuscript, and we also consider the provided suggestions to be very important and helpful for improving our manuscript. Accordingly, we have made careful efforts to revise it.
SPECIFIC COMMENT:
Point #1
COMMENT: The end of the introduction is still poor. The authors just added an overall and vague statement. The study needs a major aim/hypothesis.
RESPONSE: We deeply appreciate the reviewer’s careful review. We have modified the presentation of this sentence. (Page 2, Lines 78-80):
Therefore, the main aim of this study is to synthetically couple different models to investigate the impacts of potential climate and land use changes on hydrological processes in this watershed. There are four tasks to be completed including: a) a CA-Markov model will be advanced for facilitating an effective assessment of potential impacts of land use changes, b) SWAT will be applied, calibrated and validated to simulate river runoff, c) three scenarios including the impacts of climate and land use changes and the combined impacts of climate and land use changes will be established and analysed, and d) SWAT is used to simulate three scenarios to evaluate the future impacts of climate and land use changes on water balance.
Point #2
COMMENT: Taking (a) into account, I would like to suggest the reference Lamparter et al. (2018, DOI: 10.1007/s10113-016-1015-2). I normally do not like to suggest references, but this one was a pioneer in the use of SWAT (the same model the authors use) with land-use and climate changes and the authors do not cite it. They could use at least as inspiration to make final changes.
RESPONSE: We deeply appreciate the reviewer’s careful review and are regretful for the unclear description. We have studied this article and cited it. (Page 17, Lines 475-477):
Reference
Lamparter, G., Nobrega, R., Kovacs, K., Amorim, R. S. and Gerold, G. 2018. Modelling hydrological impacts of agricultural expansion in two macro catchments in Southern Amazonia, Brazil. Regional Environmental Change, 18 (1). pp.91103.ISSN 14363798.Doi: https://doi.org/10.1007/s1011301610152.
Point #3
COMMENT: Please include the coefficients used to assess in each figure you compare observed and simulated, and please also include coordinates in every figure you show maps.
RESPONSE: We very much appreciate the reviewer’s concern and careful review, and We have modified these figures. (Page 8-11, Lines 219-267):
Fig. 3 Observed and simulated annual runoff depths for the study catchment.
Fig. 4 Observed and simulated average monthly runoff for the study catchment.
Fig. 5 Land use maps of 1995, 2000, 2010, 2025, 2035 and 2045.
Point #4
COMMENT: I do believe that the first version of the manuscript went through English editing, as the authors say, but there are many sentences that do look weird. You only need to read the abstract to notice it.
RESPONSE: We deeply appreciate the reviewer’s careful review and are regretful for the unclear description. We have modified the presentation of these sentences. (Page 1, Lines 12-27):
Abstract：This study researched the individual and combined impacts of future LULC and climate changes on water balance in the upper reaches of the Beiluo River basin on the Loess Plateau of China, using the scenarios of RCP4.5 and 8.5 of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). The climate data indicated that both precipitation and temperature increased at seasonal and annual scales from 2020 to 2050 under RCP4.5 and 8.5 scenarios. The future land use changes were predicted through the CA-Markov model. The land use predictions of 2025, 2035 and 2045 indicated rising forest areas with decreased agricultural land and grassland. In this study, three scenarios including only LULC change, only climate change and combined climate and LULC change were established. The SWAT model was calibrated and validated and used to simulate the water balance under the three scenarios. The results showed that increased rainfall and temperature in the future lead to increased runoff, water yield and ET in spring, summer and autumn and decreased runoff, water yield and ET in winter from 2020 to 2050. However, LULC change had a smaller impact on the water balance than did climate change. On an annual scale, runoff and water yield gradually decreased in the future, but ET increased. The combined effects of both LULC and climate changes on water balance in the future were similar to the variation trend of climate changes alone at both annual and seasonal scales. The results obtained in this study provide further insight into the availability of future streamflow and can aid in water resources management planning in this study area.
Author Response File: Author Response.pdf
Round 3
Reviewer 1 Report
I appreciate the changes made. I hope you keep improving the modelling of Chinese watersheds.
