Douglas Fir Multiproxy Tree-Ring Data Glimpse MIS 5 Environment in the U.S. Pacific Northwest

Round 1

Reviewer 1 Report

The authors dated the logs with 14C isotopes and estimated that the trees probably lived between 120, 000 BP to 60, 000 BP. Then the tree ring width, 13C and 18O were measured and these three kinds of chronologies were employed. Finally, the periodicity of the three chronologies was analyzed, and the results are consistent with the periodicity of the species living in recent times. Based on the similar periodicity, the physiological ecology that the ancient data might infer was discussed. The significance of this study lies in the high resolution proxy data from prehistoric times. It’s really interesting and the data is valuable and the MS was well written. I have a few comments.

1 In my mind, many readers and authors of Forests are not familiar with the MIS, LMG etc. So I personally suggest adding some brief introduction to these terms where necessary.

2 The logs were excavated earlier, and 14C dating was carried out in your university at that time. May I ask whether the more accurate dating and carbon and oxygen isotopes used in this study are your current work or the previous data? Please clear it in the M&M section.

3 If the isotope data is what you are doing in this study, it seems to me that the main value of this study lies in the data, not the inferred conclusions.

Minor comments

1 L16, Latin names should be italicized

2 Figure1, I suggest show a picture of the polished subfossil samples.

Author Response

We want to thank you, the reviewer, for your thoughtful feedback on the manuscript and comments, which we address below. Red and blue ink mark the original and modified text in the manuscript with suggested changes. Please see the attached file.  The revised version of the manuscript (including Suppl. Materials) is uploaded into the mdpi system.  

Author Response File: Author Response.docx

Reviewer 2 Report

Review of forests-2078621, " Landslide-preserved Douglas-fir tree rings glimpse MIS5 environment in U.S. Pacific Northwest prior to 62,000 years ago". In this study, the age of the buried ancient trees was identified, further, the tree-ring width, stable carbon and oxygen isotope chronologies were established, the response relationship of tree-ring parameters to climate was analyzed, and compared with the modern tree rings-climate response relationship. Some meaningful conclusions were obtained. It submitted to forests for publication is certainly dealing with a topic which is of interest for the readership of the journal.

Before publication the authors should address the following issues:

1. It is suggested that the title should be changed to “Douglas-fir tree rings glimpse MIS5 environment in U.S. Pacific Northwest”.  

2. I suggest that the Figure 1 should have basic map elements, such as orientation, legend, scale, etc.

3. Can the authors clearly show the similarities and differences between ancient and modern tree-ring parameters? Since both the Last Interglacial and the modern era were warm periods, the climatic conditions should be close or similar, so are the tree-ring chronologies similar in low frequency variation? I think it should not be difficult to show the ring width, stable carbon and oxygen isotope chronologies of living trees.

4. The study does not substantially analyze the relationship between ancient tree ring parameters and climatic environment. I understand that this is because there is no climatic data with ancient annual resolution, but it is suggested that the author should weaken this description. The emphasis can be placed on the comparison of various parameters between ancient and modern times and the possible enlightenment.

 

Author Response

We want to thank you, the reviewer, for your thoughtful feedback on the manuscript and comments, which we address below. Red and blue ink mark the original and modified text in the manuscript with suggested changes. Please see the attached file.  The revised version of the manuscript (including Suppl. Materials) is uploaded into the mdpi system.  

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

To me, the manuscript is ready for publication.