Macronutrient Content in European Beech (Fagus sylvatica L.) Seedlings Grown in Differently Compacted Peat Substrates in a Container Nursery
Round 1
Reviewer 1 Report
The results here presented are interesting, and direct consequence of a well designed and well-done study. I must confess that I have never read something like the topic here before, in spite of being concerned with forest resources for more than 35 years. So, the paper illustrates how we are far from having a complex scope of the whole matters involving forest tree management.
I have just a question that should be answered, if possible. Are the values of compaction here subjected to tests usually found in the context of forest nursery? Is a common practice to induce such substrate compaction by using tools? This is important for me, as it gives the "real" focus of the study, as a way to advise against this practice in the future...
Author Response
We are grateful for reading our paper, for the review and for your interesting questions, which enabled us to improve the paper.
We first answer your question about compaction level commonly used in forest nurseries. For comparison, at the same time in the container nursery where the experiment was conducted, the density for seedlings grown in identical cells as used in our experiment, was about 0.099 g/cm3 (which is between variants V4 and V5 in our experiment). It should be noted that such a density is used for all species that grown in such a cell size (265cm3), and our research so far shows that the density should be adapted to the tree species.
The second issue concerning the possibility of adjusting the density depends on the production line. On the BCC line we used, one can change the density using pistons (2 levels - 1 press or 2 presses) and the level of vibration when the container moves along the production line. Unfortunately, in practice most often no tools are used to check the density of the substrate. The assessment consists in putting a finger into the container cell after filling the first cassette and subjectively assessing by the nursery worker (based on his/her experience) whether the substrate is too loose or too dense. A penetrometer is a tool that could be used for this purpose to obtain more exact and reliable measurement.
W added information about testes of substrate compaction (lines 61-70) and capacity to the paper (lines 108-109).
Reviewer 2 Report
The article reads good and I don't have any major comments. The only minor comment I have is to mention clearly in the discussion about how different cultivars can have different root system architecture and that can alter the nutrient acquisition in addition to compactness of soil used.
Another minor comment is to change the comma to decimal point in the tables and figures.
Author Response
We are grateful for reading our paper, for the review and for comments, which enabled us to improve the paper.
In our experiment we used seeds having the same provenance (seeds were harvested at the same time from the same forest stand), to reduce the risk of various cultivars having impact on our experiment. We added information about the origin of the seeds to the paper (lines 116 – 117).
We changed comma to dot in the tables and figures.
