The Influence of Different Climate and Terrain Factors on Vegetation Dynamics in the Lancang River Basin

Round 1

Reviewer 1 Report

Vegetation plays an important role in soil and water conservation, regulating the atmosphere and maintaining ecosystem stability, as well as influencing regional hydrology and watersand processes. In this study, spatial patterns in the response of the climate and terrain factors to vegetation were examined in the Lancang River basin. The author draws support from a Geographically Weighted Regression and MODIS NDVI data. The study finds that the effects of climate and topographic factors on NDVI are the same in Yunnan section, but opposite in Qinghai section and Tibet section. This work is helpful to understand the dynamic effect of vegetation and is a push in the Langcang River Basin. The current manuscript has lots of unclear and suggest to make a major revision before publication. The detailed comments and suggestions are as follows:

(1)   In the Introduction part, reviews about research progress is not enough. The author doesn’t follow a good logical line to straighten out the previous research, and doesn’t reflect the innovation of this article.

(2)   Figure 1 should show the province boundary.

(3)   In the methodology, MK test is common and well known. The author doesn’t need to give a so detailed presentation.

(4)   This study focuses on the period 1998-2020. Theoretically, a longer study period will be better to explore the influence of climate and terrain factors on vegetation. In this manuscript, the author only chooses the period 1998-2020 to carry out research. What is the author's reason? Data availability or other reasons?

(5)   The quality of some figures are not good, with bad resolution, such as Figure 2, Figure 3.

(6)   Lines 206-207, “and the fluctuation of standard deviation is small”, I don't know where the author came from.

(7)   Figure 7 show the soil types in Lancang River Basin. This part should move to “Study area” as a background together to introduce the study region.

Author Response

Point 1: In the Introduction part, reviews about research progress is not enough. The author doesn’t follow a good logical line to straighten out the previous research, and doesn’t reflect the innovation of this article.

Response 1: Lines 51-61, rewritten the research progress section.

Point 2: Figure 1 should show the province boundary.

Response 2: In figure 1 provincial boundaries have been added.

Point 3: In the methodology, MK test is common and well known. The author doesn’t need to give a so detailed presentation.

Response 3: The presentation of the MK test has been abridged.

Point 4: This study focuses on the period 1998-2020. Theoretically, a longer study period will be better to explore the influence of climate and terrain factors on vegetation. In this manuscript, the author only chooses the period 1998-2020 to carry out research. What is the author's reason? Data availability or other reasons?

Response 4: Because the NDVI data I used relied on satellite images provided by SPOT/VEGETATION PROBA-V 1KM PRODUCTS, which only provided satellite image data from 1998-2020.

Point 5: The quality of some figures are not good, with bad resolution, such as Figure 2, Figure 3.

Response 5: The pixel of Figure 2 and Figure 3 have been adjusted to 300dpi.

Point 6: Lines 206-207, “and the fluctuation of standard deviation is small”, I don't know where the author came from.

Response 6: Line 255, the annual average precipitation in Qinghai, Tibet, and Yunnan are 650.9±75.4, 674.9±79.5, and 1341.9±133.7mm respectively. The standard deviations are 75.4, 79.5, and133.7 respectively. Therefore, I think the standard deviation becomes smaller as the altitude increases.

Point 7: Figure 7 show the soil types in Lancang River Basin. This part should move to “Study area” as a background together to introduce the study region.

Response 7: Figure 7 has been added to the study area background presentation.

Author Response File: Author Response.pdf

Reviewer 2 Report

Title: The Influence of Difference Climate and Terrain Factors on Vegetation Dynamics in the Lancang River Basin

Reports of vegetation in response to regional climate, soil and hydrology in river basins are increasingly concerned. This study attempts to discuss the influence of difference climate and terrain factors on vegetation dynamics in the Lancang River Basin. The topic itself is important and writing skill is good. However, detailed information about the study area is lack, and more in-depth discussion about correlation coefficients is necessary. Thus, the manuscript still needs to make some improvements before publication. Detailed comments or suggestions are as follows.

1. Line 69, I suggest you to highlight the contributions/scientific value/applicability of your findings at the end of the “Introduction” section.

2. Line 72-79, important information about the Lancang River Basin is lack. E.g., meteorology, hydrology, rock, soil and land use. These may greatly affect climate, terrain and vegetation types.

3. Line 164, Fig. 2. (i) The abbreviation LCR should be defined before used. (ii) LCR, Yunnan, Qinghai and Tibet should be introduced in the section of “Materials and Methods”, particularly in Fig. 1 (mark it).

4. Line 193-195, change to “91.69%, 90.66% and 88.23%” and “5.94%, 6.93% and 8.59%”.

5. Line 242, how to describe or classify e.g., extremely strong negative correlation, strong negative correlation, moderately negative correlation…Are they related to correlation coefficients? How to judge whether these "correlations" are statistically significant?

6. Line 285-295, I did not find Fig. 10. Please check figure numbers and captions throughout the manuscript.

7. Line 285-319, you attempt to explain GWR correlation coefficients between e.g., elevation and NDVI, slope and NDVI, precipitation and NDVI…Current views suggest that the correlated factors do not necessarily have a causal relationship. This should be noted in the section of “Discussion”.

Author Response

Point 1: Line 69, I suggest you to highlight the contributions/scientific value/applicability of your findings at the end of the “Introduction” section.

Response 1: Lines 78 - 79, added discussion of scientific value.

Point 2: Line 72-79, important information about the Lancang River Basin is lack. E.g., meteorology, hydrology, rock, soil and land use. These may greatly affect climate, terrain and vegetation types.

Response 2: Lines 82-94, added information about meteorology, soil and land use.

Point 3: Line 164, Fig. 2. (i) The abbreviation LCR should be defined before used. (ii) LCR, Yunnan, Qinghai and Tibet should be introduced in the section of “Materials and Methods”, particularly in Fig. 1 (mark it).

Response 3: Line 174, LCR has been defined. The provincial boundaries have been marked in Figure 1 and introduced in the overview of the study area.

Point 4: Line 193-195, change to “91.69%, 90.66% and 88.23%” and “5.94%, 6.93% and 8.59%”.

Response 4: I have modified it.

Point 5: Line 242, how to describe or classify e.g., extremely strong negative correlation, strong negative correlation, moderately negative correlation…Are they related to correlation coefficients? How to judge whether these "correlations" are statistically significant?

Response 5: Pearson correlation coefficient ranges from -1 to 1, and it is divided into 10 grades with 0.2 as the boundary. The statistical significance has been explained in line 264.

Point 6: Line 285-295, I did not find Fig. 10. Please check figure numbers and captions throughout the manuscript.

Response 6: I have modified it.

Point7: Line 285-319, you attempt to explain GWR correlation coefficients between e.g., elevation and NDVI, slope and NDVI, precipitation and NDVI…Current views suggest that the correlated factors do not necessarily have a causal relationship. This should be noted in the section of “Discussion”.

Response 7:Line-293-295, it has been explained.

Author Response File: Author Response.pdf