Monitoring Individual Tree Phenology in a Multi-Species Forest Using High Resolution UAV Images
Round 1
Reviewer 1 Report
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Author Response
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Reviewer 2 Report
The authors used UAV images, and try to capture the species level phenology. They've tried to differentiate different trees first, and tested phenology captured by different vegetation index. The whole idea is interesting, however there are a few major flaws that affect the quality of this paper and the study.
1. Only 14 images are used. The temporal frequency is too low for phenology monitoring, especially for the fall season.
2. In figure 5, for oak and birch, there are no sufficient monitoring to decide the baseline or background value. This affects the actuary of phenology detection.
3. In figure 5, the meaning value of red line is not mentioned in the paper. And I don't think they are logistic fitting, as they look to straight for a non-linear fitting.
4. The novelty and contribution of this study is unclear. The paper spent lots of content on classification method. However, this does not seem to be the main object of the paper. This also leads to the whole writing of the paper is not telling a whole story.
The quality of English is average, and can be improved.
Author Response
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Reviewer 3 Report
General comments:
This is an interesting study testing the use of VIs derived from UAV images for individual tree crown phenology. I think the paper is excellent in format, language and content.
Minor specific comments:
Line 4: "breach this gap" the gap hasn't yet been articulated.
Regarding the top 20% of VIs: was this the top 20% overall (from the study area) or each individual tree's top 20%? The workflow is slightly different.
Line 348: "the average VI values" - I think this is not correct, the top 20% were taken. This is just a necessary wording change.
Author Response
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Round 2
Reviewer 2 Report
The authors have addressed all my questions, and the paper has been improved.
Several minor revisions are needed, such as the meaning of thin white line in figure 3 is not provided in the caption. Authors are to suggested to check the whole paper to make sure to explain all the elements in the figures clearly.
Author Response
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