Old-Growth Forest Disturbance in the Ukrainian Carpathians
Round 1
Reviewer 1 Report
The paper could be improved by thorough editing. Punctuation, which would make the paper easier to read, is missing from many phrases. Other sections are unnecessarily wordy. The figures (especially the maps) are a little poor in quality.
I also feel that the Discussion is largely missing. There is little comparison to other studies, or reflection on limitations, future opportunities etc. Also, does the 2017 law supersede all previous laws? Some discussion around this would be beneficial.
Some specific comments are as follows:
Line 18: This is the first use of OGF as an acronym
Line 22: I would change “natural old-age” to “natural age”
Line 26: What is “climate mitigation”? I guess you mean “climate change mitigation” (or you could mean “climate regulation”). A young regenerating forest probably sequesters more carbon than OGF, so I don’t think the statement is true anyhow.
Line 28: Needs punctuation
Line 50: “should now be” should be “are now”
Figure 1 should be bigger
Line 110: What is the “L” for? I assume it stands for Latin, but it is not needed here or in lines 117-120
Line 109: The tree species information would be better in the ‘study site’ section, in my opinion (if it is relevant)
Line 111: What is “(Matt.) Liebl.” and why is it in the text? Same goes for “Roth” and “(Chaix.) D.C.” at lines 118-119…
Line 122: comma needed after “slopes”
Figure 2: I would prefer ‘proportional’ to ‘fractional’
Line 148: Should say “Figure 3” not “Figure 2”. Also, need full-stop after area
Line 201: “has the advantages of being accurate” should be removed or rewritten as something like “has shown accurate results in complex forest types”
Line 228: I would remove “Random Forest”
Line 241: This seems to be results rather than methods
Line 291: It would be better to say “see section x.x” instead of “see Methods”
Table 3 is a figure, not a table. Also, I find the colours very difficult to read
Figure 5: It is difficult to see any OGF loss in panel (a) or the main map
Author Response
Response to Review
Old-growth forest disturbance in the Ukrainian Carpathians
B.D. Spracklen and D.V. Spracklen
Reviewer 1:
We would like to thank the Reviewer for their thorough and careful review of our paper. Our responses to their comments are in italics.
The paper could be improved by thorough editing. Punctuation, which would make the paper easier to read, is missing from many phrases. Other sections are unnecessarily wordy.
Response: We agree that the paper reads oddly and has strange sentence construction in places. We have gone through the whole paper and tried to improve readability by rearranging sentences and adding punctuation. The Methods section seemed wordy, and we have cut some of the information, for example on tree species composition and treeline, that was not really necessary.
The figures (especially the maps) are a little poor in quality.
Response: Agreed. We have worked to improve the quality of the figures. We have completely redone Fig 6 (the map of OGF loss) and improved Fig 1 (map of OGF.)
I also feel that the Discussion is largely missing. There is little comparison to other studies, or reflection on limitations, future opportunities etc. Also, does the 2017 law supersede all previous laws? Some discussion around this would be beneficial.
Response: We have added a couple of paragraphs to the Discussion, including:
looking at other papers that dealt with forest loss in temperate Europe (Lines 380-396)
In contrast to tropical areas, there has been comparatively little published work on forest loss and Protected Area effectiveness in Central and Eastern Europe. A study of OGF disturbance rates in the Romanian Carpathians from 2000 to 2010 [41] found, contrary to our results, little difference between disturbances in protected and unprotected OGF, with only National Parks found to be effective in reducing loss. Likewise, a paper [62] looking at the Caucasian Mountains (Russia and Georgia) from 1985 to 2010 found PAs to be ineffective, though forest loss was very low both in and out of PAs. Other studies have seen mixed results, with a study[71] of all forest in Central European Russia (1985-2010) finding strictly protected areas (IUCN I) to be effective, and multiple use PAs (National Parks and zakazniks) ineffective in preventing forest disturbance. A paper looking across the whole Carpathian region from 1985 to 2010 [20] found reserve effectiveness to vary strongly both with time and between the 6 studied countries.
Further, we discuss the wider situation in the Carpathian region and any light our study throws on their situation (Lines 327-333).
The Carpathian Convention committed its signatories (Ukraine, Romania, Poland, Serbia, Slovakia, Hungary and the Czech Republic) to the protection of their virgin forest. The three first-named counties have significant areas (>10000ha) of OGF. In neighbouring Romania, an amendment to the Forest Law in 2008 (similar to the 2017 Ukraine law) protected OGF areas from logging, but only more recently have effective criteria [63–65] as to what forest qualifies as OGF been developed. Anecdotally[66], there seems to be a lack of effectiveness so far due to limited progress in OGF designation, and it would be interesting to see how the situation in Romania contrasts with our results in Ukraine.
We clarify the impact of the introduction of the 2017 ban on OGF logging (Lines 317-319).
Prior to the introduction of this law, OGF enjoyed no specific protection beyond what was provided by their location within a Protected Area or forest management regime. Post May 2017, all OGF is strictly protected, regardless of location or management regime.
Some specific comments are as follows:
Line 18: This is the first use of OGF as an acronym
Response: changed to old-growth forest.
Line 22: I would change “natural old-age” to “natural age”
Response: changed as requested
Line 26: What is “climate mitigation”? I guess you mean “climate change mitigation” (or you could mean “climate regulation”). A young regenerating forest probably sequesters more carbon than OGF, so I don’t think the statement is true anyhow.
Response: changed to climate change mitigation. We acknowledge that younger forests might sequester more carbon than OGF, but OGF store more carbon meaning they are also important.
Line 28: Needs punctuation
Response: changed to “In many European countries, the extent of OGF has been dramatically reduced through millennia of deforestation and disturbance and, more recently, conversion to managed plantations.”
Line 50: “should now be” should be “are now”
Response: changed as requested
Figure 1 should be bigger
Response: Increased its size, and rearranged slightly to hopefully make clearer.
Line 110: What is the “L” for? I assume it stands for Latin, but it is not needed here or in lines 117-120
Response: The MDPI Forests style guide (https://www.mdpi.com/journal/forests/instructions) instructs authors “Latin binomial nomenclature and authority should be provided after each common name the first time referred to in the text”, so even though we agree with the Reviewer that it is not usual practise, we feel that we have to include the authority names L., (Matt.) etc
Line 109: The tree species information would be better in the ‘study site’ section, in my opinion (if it is relevant)
Response: We have cut many of the lines on tree species composition as not essential
Line 111: What is “(Matt.) Liebl.” and why is it in the text? Same goes for “Roth” and “(Chaix.) D.C.” at lines 118-119…
Response: As for Line 110
Line 122: comma needed after “slopes”
Response: added as requested
Figure 2: I would prefer ‘proportional’ to ‘fractional’
Response: changed as requested
Line 148: Should say “Figure 3” not “Figure 2”. Also, need full-stop after area
Response: Changed as requested
Line 201: “has the advantages of being accurate” should be removed or rewritten as something like “has shown accurate results in complex forest types”
Response: rewritten to “ It has the advantage of being capable of giving accurate results in complex forest types”
Line 228: I would remove “Random Forest”
Response: removed as requested
Line 241: This seems to be results rather than methods
Response: The sentence “The Random Forest classification identified 633 OGF disturbance polygons (2015-2019 inclusive), covering 245 ha, or 18% of the total OGF disturbance area identified.” was moved to Results.
Line 291: It would be better to say “see section x.x” instead of “see Methods”
Response: changed to Section 2.5.
Table 3 is a figure, not a table. Also, I find the colours very difficult to read
Response: Changed to Figure as requested
Figure 5: It is difficult to see any OGF loss in panel (a) or the main map
Response: This Figure was of unacceptable quality. We have completely redone it, using OGF centroids on the main map of varying size to show OGF loss.
Reviewer 2 Report
Some very small corrections proposed in the text.
Comments for author File: 
Comments.pdf
Author Response
Response to Review
Old-growth forest disturbance in the Ukrainian Carpathians
B.D. Spracklen* and D.V. Spracklen
Reviewer 2:
Line 18 OGF abbreviation not explained in abstract
Response: changed to old-growth forest.
Line 35.. Convention [9], a ...
Response: changed as requested
Line 148: Figure 3
Response: changed as requested
Line 173 granules
Response: changed to granules
Round 2
Reviewer 1 Report
The authors have addressed my previous comments adequately. I have nothing further to add. Well done.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
The primary focus of the study is on disturbance rates in old growth forests in Ukraine. The hypothesis that the recent amendment of the forest code has led to reduced rates of disturbance is a worthwhile line of research. However, your conclusions are a little weak in this regard, due to limited data/time-frame. Your results suggest no change in 2018, followed by less disturbance in 2019. Presumably your 2019 image is from reasonably early in the season (meaning a short year), and it is possible that the low rate in 2019 could be an anomaly.
From a remote sensing perspective, it is not clear how the duel use/comparison of Landsat and Sentinel fits into the aims of the paper. Your argument appears to be that Sentinel will give better results due to its better spatial resolution, however your results suggest Landsat is just as good. In some respects, the paper would be stronger (or at least simpler) by just using one sensor. If you retain both, it would be better if you compared Landsat and Sentinel to all the overlapping years (e.g. 2015-2019). You could also create a model using both sensors, although I don’t think accuracy (which is already quite high) would change much.
I also think you could run your disturbance model on all years that Landsat data (30m) is available (1980s onwards), using all OGF polygons to define your study area. Unless, that is, you are making the assumption that forest classified as OGF by the WWF after 2010 was essentially undisturbed prior to its designation? This is not clear in the paper. Disturbance rates over 30 years would be a more compelling study.
The paper also suffers a little by the use of so many categories. At its simplest, it is about how much disturbance you have found in OGF between 2010 and 2019 (3.9% of total area). You then break it up by year, species, elevation, protection category, etc. As you have found, you end up with tiny areas/percentages in many cases. I am inclined to think that the small disturbance areas may not be significant. You could consider removing or grouping some of these categories, or present results in tables, to make it more accessible to the reader.
Some other comments are as follows:
Figure 1 could be improved. It is difficult to distinguish the areas of old growth forest from the background terrain. The inset map should be larger. North arrow and scale bar would also be useful.
Figure 2 seems unnecessary, as in most of the paper you refer only to 9 species categories (e.g. beech, mountain pine, etc.)
The colours used in many of your charts don’t seem to mean anything. I think a single colour would suffice in most cases.
Table 1 could be summarised, removed or put into an appendix. While the quotes from obscure laws demonstrate a range of protections, the words themselves are not all that relevant. I am also unsure of the current status of these laws, given that the new law passed in 2017 seems to override these…? Perhaps this could be clarified somewhere in the paper.
Regarding methods in general, I think greater focus/clarity is needed for the modelling and accuracy assessment sections, as these are the foundations that the rest of the paper are based on. The other sections in methods could be more succinct.
Line 206: I would reword. In my opinion, RF doesn’t analyse large images. RF is used to create a model based on a subset of pixels, which is then used to classify the image(s).
Line 209: It is not clear how you generated your reference data for the Random Forests model. As one of the essential parts of the paper, this needs more explanation. How did you manually select the polygons and how did you interpret them? What years were they from, etc.? How many pixels were used in the final model?
Line 215: Try to be consistent with formatting/style (e.g. ‘2010-2014’ and ‘2015 to 2019’)
Lines 229-230 is confusingly worded
Line 236: this is not correct. There are many studies using Random Forests to classify disturbances into different categories (e.g. wildfire, logging, insects). See ‘Kennedy et al. 2015 - Attribution of disturbance change agent from Landsat time-series in support of habitat monitoring in the Puget Sound region, USA’ as one example
Lines 241-242: I would change “was” to “has been” to make it clear you are referring to other studies
Line 245: How many pixels did you validate in total? Is it 50 per year?
Line 247: I disagree with this statement, as there are many disturbances which cannot be detected from satellites. I think you need to nuance your language here. Something along the lines of ‘manual interpretations have been shown to provide accurate results’.
I would prefer Results and Discussion to be separated
I would prefer these results presented as a confusion matrix (with total number of pixels). It is also a bit unclear what you mean by N=30. If N is the number of scenes, did you interpret 50 pixels in each scene and then average the results? I also don’t know what the (e.g.) +-1.4% means. Is this one standard deviation? Or a 95% confidence interval.
Line 270: I would say the high accuracies are a function of the training and validation data. When you train the model with classes that quite distinct spectrally and then assess the accuracy by manual interpretation of the same data (e.g. Landsat and Sentinel) you may be missing subtle disturbances.
Line 272: The area estimated by Landsat also may be greater because earlier forest disturbance (e.g. from 2010) has ‘recovered’ by 2015.
Line 283: A lot of disturbance studies, using Landsat in particular, remove single pixels, as these are often just noise.
It is not clear what you mean by ‘% a-1’. Do you mean % per year (% year-1)
Figures 4, 5 and 6 could be more aesthetically pleasing and again in figure 7, the colours are meaningless/distracting.
Line 326: Does this ban on logging on steep slopes still have relevance with the new law banning all logging in OGF?
Figures 8 and 9 and the accompanying commentary are not results as such (i.e. not showing disturbance rates). Therefore, they could be removed or otherwise should be in methods/appendix.
Line 377: This sentence seems to repeat the previous one. It is also confusing, because you have said disturbances were higher, but I think you mean disturbances were found in areas of higher elevation.
In the Conclusions, I think you need to be careful not to let too much opinion creep in, or to push an agenda. Particularly line 427. While you may have looked into regulations, you did didn’t investigate enforcement or certification. Most of the last paragraph could probably be removed.
Reviewer 2 Report
Interesting manuscript, but I have some serious reservations:
General comments:
First, many of the data presented (Figs. 1, 2, 3; Tale 1) are not results of the work of the authors, but adopted from other resources (WWF). Although it's clearly acknowledged and such data are presented in the Material and Methods section, the space for these data is inadequately high. Other presented data are a result of simple GIS overlay of external resources (e.g. Figs. 8 and 9). I believe that good scientific paper should be more based on the results of original research.
Although the reported mapping accuracy of forest-cover loss really may be really considered as relatively high compared to similar applications, with respect to observed phenomena (annual rates of OGF loss) it is probably insufficient. Possible misclassification is approximately equally likely as studied phenomenon itself (the OGF loss). So the study can perhaps identify some trends, but the reported rates must be taken with caution (be aware of uncertainty due to misclassification). I also don't like the approach that all observed disturbances were considered as human impact. There is surely some natural disturbance regime, so especially for detected forest-cover loss of one or few isolated pixels this should be taken in account.
There is probably too many pictures in the manuscript compared to its information value
Specific comments:
Please consider other term to 'forest disturbance', which is also part of natural forest dynamics. As you study the human impact on OGF I suggest something like 'OGF loss'.
Your Conclusions is rather a Summary.
Reviewer 3 Report
Text of the article should be complemented with following information:
Part 2.2 contains summary on tree species composition. While silver fir is important species (4th largest area) and it usually creates - together with beech and spruce - stands of so called "Carpathian mixture" and is typical species in OGF due to its longevity and high stocking, this species is not mentioned in the text.
As mentioned in 2.5, analyses of the distance to the nearest settlement included settlements in neighbouring countries. However, due to the strict border regime (both present and past) especially in case of Poland and Slovakia (outer Schengen boundaries), it is questionable whether trans-border settlements can have influence on OGF in Ukraine. What would be the results of distance analyses in case these settlements would be excluded?
Due to the availability of satellite scenes, the length of "years" varies in evaluation period. What was the length of 2019? Could it influence results (decrease of disturbance) in 2019?
