Production Capacity Evaluation of Farmland Using Long Time Series of Remote Sensing Images
Round 1
Reviewer 1 Report
Title: Production Capacity Evaluation of Farmland using Long Time Series of Remote Sensing Images. The subject is interesting, but some minor revisions should be considered.
- The abstract should be made in a more concise manner, methodological part should be stated in a good way.
- Abstract, NDVI, abbreviations should be defined the first time they appear in the text.
- Add the novelty of your work at the end of abstract section.
- Please add related works at the end of the introduction section.
- Please introduce a hypothesis retain/reject at the end of Introduction.
Author Response
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Reviewer 2 Report
Article "Production Capacity Evaluation of Farmland using Long Time Series of Remote Sensing Images" is well written and adequately summarized. In the time of modern agriculture, we need to understand the importance of farmland and evaluate its production capacity by using different machines and specifically remote sensing. The article is to evaluate the farmland production capacity at the county scale using time series remote sensing(RS) images. This research enlighten the new doors of research and able to explore the remote sensing and AI scientists to determine their directions in the course time. The article is well written and will be able to gather the original research audience. Please clarify the objective of the study in the introduction section. The discussion needs to be correlated. The discussion is a fragment please consider it to make a story. English needs some changes with grammatical mistakes.I would recommend you please consider the latest articles for citation.
Author Response
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Reviewer 3 Report
Review : « Production Capacity Evaluation of Farmland using Long Time Series of Remote Sensing Images »
The manuscript describes a method to is to evaluate the FPC at the county scale using time-series remote sensing imagery (Landsat and Sentinel).
The bibliography is rich with a lot of works describing methodologies that follow the same purpose as the authors, from satellites remote sensing images and other RS techniques. However, on the case of the submitted manuscript, the methodology describes a lot of gaps, that weaken the followed steps and the presented results. For this reason, adding to that the missing of the novelty of the work, I believe that the paper has not the potential for being published by Agriculture.
Comments
Abstract : Change the keywords to « short » keywords composed from one or two words.
“At present, the application of RS in evaluating FPC was to extract the multiple cropping index and active days using time series EVI derived from RS image.“: The structure of the sentence made it appearing as the use of remote sensing techniques for the evaluation / estimation of the FPC is limited to the use of the indexes. However, it is not the case.
GPP ? You should add the complete names of the abbreviation on its first use.
“However, GPP changes were influenced by climate change, ….. monitoring crop growth and evaluating the FPC.”: The literature review is rich by studies based on much more advance use of remote sensing tools for the FPC estimation. However, I do not understand why those studies were neglected, and ancient researches were cited. Putting on value your work, does not signify excluding other works.
“The remote sensing images with medium resolution, such as Sentinel and Landsat, can be used to grasp the spatial changes of farmland.” Such satellites were already use for this purpose. Please update your bibliography.
“The purpose of this study is to evaluate …… between FPC and soil organic matter.”: Before listing your work objectives, you should include a paragraph describing the novelty and the added value of work to the research; and how your work is different from already published previous studies.
The Introduction is poor of recent studies and researches describing the advances of the remote sensing tools / techniques / methodologies within the paper purpose.
“with a total cultivated area of about 549 km², which is a large grain-producing county in Hebei Province“: The authors must include details about the vegetation characteristics within the interested area.
“The soil type in the study area is mainly brown soil and tidal soil”: The authors need to include more details describing the soil characteristics (e.g., soil texture, soil organic carbon SOC content, etc.).
“Referring to the agricultural land classification regulations issued by the state”: Add the reference, please.
Figure 3. Spatial distribution of field sample sites: The number of the sampling points considered in relation with / comparison to the covered surface area is not enough.
“Because there are few confused crops in the same period, winter wheat is easy to be
identify by remote sensing.”: How ??? How the winter wheat is easily detected by remote sensing ? What technique are you referring to ? NDVI is a good indicator of the status of vegetation, but it is not enough.
The methodology followed by the authors presents a lot of gaps while mapping the winter wheat on the areas of interest. The criteria selected by the authors are not enough to delimit with a high probability only winter wheat. Which implies that those maps could not be used as reference for the yield estimation.
“The results showed that the models could fit the yields well and the stability of the models was good.”: Do you consider R2 values at the range of 0.43 – 0.54 as good models ?
“Figure 5. The relationship between the measured value and the predicted value of winter wheat yield.” The statistical analysis followed to present the relationship between measured and predicted values are not sufficient. That’s from one side, from another side, (i) the plotted data is not enough and (ii) the presented statistical analysis are in the majority of the cases moderate.
“However, crop yield was estimated in this study only through NDVI, which was widely used in vegetation remote sensing.” Only NDVI is not sufficient for the purpose of the research. The bibliography is rich of published papers combining NDVI with other factors to increase the certainties.
Author Response
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