Vegetation Productivity and Precipitation Use Efficiency across the Yellow River Basin: Spatial Patterns and Controls

Round 1

Reviewer 1 Report

- The study focused on investigating the spatial patterns of Vegetation productivity and precipitation use efficiency in the Yellow River Basin using land-cover maps, long-term MODIS NPP datasets, and meteorological information.

- Why did you select the period from 2016 to 2020 for your study and data analysis?

- It is recommended to provide a flowchart to show the methodology adopted in this study, as well as provide a description of the image processing steps of the remote sensing data used in this study.

- Did you perform any fieldwork in the study area for validation of the remote sensing data analysis? if yes, then provide more details.

Author Response

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Reviewer 2 Report

The approach that is presented in this paper is interesting and important for general understanding of the relationship between environmental factors and ecosystem response and functioning.  Although, the idea is not quite a scientific breakthrough and I did not found no scientific novelty, I think it worth to be presented and will recommend it for publishing after several issues will be addressed. 

The major point is that I would recommend to be more specific on why focusing the research on the certain area (YRB). Why it is important and how the results of the study could be applied in similar regions/climatic zones/ecosystems. I’ve missed this point all over the manuscript.

Another point is why the authors are focusing on AP and not other measures? This point is also wasn’t clarified throughout the paper.

I also would recommend English editing.

Here some specifics.

L. 115 - 116 How many points were used in the study? Only five?

L. 123 Please, be specific- what other variables have been collected?

L. 164 Seems like not enough data to be qualified as MAP. Please, elaborate more on why other years haven’t been used.

L. 184 -186 this hypothesis looks quite obvious

Table 1 Are those averages for the entire basin?

Figure 5 The numbers near the arrows are  very small. Please, try to enlarge it

Author Response

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Reviewer 3 Report

Dear authors,

The study of vegetation productivity and precipitation utilization efficiency in the Yellow River Basin is of certain practical significance for maintaining the stability of the basin ecosystem and promoting the high-quality development of the basin.

1. The thesis of your paper is "Vegetation productivity and precipitation Utilization efficiency in the Yellow River Basin: Spatial pattern and controls", which needs to fully sort out the existing problems in this aspect and carry out targeted analysis and demonstration. Due to the complexity of the YRB, it is necessary to carry out research through typical or representative regions. This study is still macro in terms of research ideas and methods, and it is suggested to be further specific.

2. The first conclusion mentioned in the abstract is the regional differentiation law of water and heat conditions in natural geography, which is a common sense understanding and has no innovative value.

3. The conclusion that the climate is drying is not accurate enough. Rising temperatures are common at both global and regional scales, but they are not the same thing as drying. Precipitation is also increasing in many places, creating a wetter trend. Therefore, it needs specific analysis for different regions. At the same time, the growth and change rules of different natural vegetation and artificial vegetation are different, so the NPP and PUE are also different. It is necessary to combine the zonal change law of hydrothermal conditions and the distribution law of vegetation to carry out targeted coupling analysis, which has more theoretical value.

4.The upper, middle and lower reaches of the Yellow River basin are different in physical geography.The formation, transformation and consumption of water resources in the basin are complicated.Meanwhile,industrial structure and social economic development level is different.It is necessary to carry out targeted analysis in order to reveal more scientifically the problems of vegetation productivity and precipitation utilization efficiency,and to reveal the spatial pattern and regulation.For the correlation analysis of productivity and PUE of woodland, shrub and grassland, it is necessary to combine the spatial and temporal differences of water and heat conditions in the basin and the spatial differences of geomorphic features expressed by DEM.It is not sufficient to use longitude, latitude and altitude only for general analysis.

5. Issues related to spatial pattern need the support of the principles and methods of physical geography, landscape ecology and other disciplines. This study lacks the overall guidance of relevant principles and theoretical analysis of specific problems, and the connection between the realities of different regions is not close enough.

6. In the Discussion section, the literature listing is relatively common. “Spatial Pattern Characteristics of NPP and PUE”,"Hydrothermal controlling mechanism of NPP and PUE spatial patterns", The analysis of "Implication for revegetation and land management" is not comprehensive, lacks the pertinency of theory and reality analysis, and elucidation of the author's view is not sufficient either. In particular, the comprehensive effects of water and heat conditions, vegetation change and anthropogenic activities at the scale of the Yellow River basin, and the scale effects of NPP and PUE under specific environmental conditions have not been thoroughly analyzed.

7. Many professional words and phrases need to be considered. Such as” highly fluctuating topography”; Many parts of the use of “fluctuating”, be sure to accurately.

8. Figure 1 is not standard enough. The map of China in the upper left corner of the frame should be moved to the outside of the frame. It is recommended that the necessary geographic information elements be annotated in Figures 1 and 2.

9. The description font of references in the text should be unified, and the description format of references at the end of the text should be checked and standardized one by one. There are many errors and omissions in page numbers and symbols.

10.There are many errors and omissions, which must be improved. (1) Line 85 ".." , a "should be deleted." . (2) After the first expression of the abbreviation, the original text and the abbreviation should not appear again. (3) Lack of punctuation after line 169. (4) In "andPUE" on line 178, there should be a space between and andPUE. (5) The dimensions of NPP and PUE in Table 1 must be standardized.

 

regards,

Author Response

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Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

 Accept in present form