If my questions can be addressed and it is only a matter of clarification, it should only be minor revisions. If they can't be addressed easily, it will be major. Please see details in the attached pdf.

The manuscript submitted by G. Chen and colleagues describes a very nice study on the determination of emissions of the main greenhouse gases (GHG) CO2, N2O and CH4 and the related Global Warming Potential (GWP) from an oil palm plantation in Indonesia. The experimental setup and statistical analyses appear to be sound and the results are presented in a nice and understandable way.

I think that this study has the potential to be published in Biogeosciences – there are, however, some things that should be re-worked and re-written.

In general, it is not always clear to me which of the results have been obtained in the manuscript presented here and which have already been reported and published in previous studies. From what I understand have different publications come out of the experiment (which is great!) and the GHG measurements are part of this particular manuscript. Sentences such as ll. 317 – 318 make it  difficult to understand if the emission peaks and pulses have been observed in this study (the material is presented in the supplementary material) or in the publications that are cited.

Please repeat hypotheses in the Results and Discussion sections (e.g., l. 281, l. 289, l. 316, l. 332). As the hypotheses are not numbered in the Introduction (ll. 95 – 100), it is not easy to re-call which of them was first and second when coming to the Results and Discussion.

In the Conclusions, I am missing some advice and future outlook, e.g., with regard to farmers. The suggestions presented originate mainly from another study on oil palm planation on a slightly different soil. What is the outcome of this study and how can/should this be used in practice?

Please find some more minor comments below.

Introduction

ll. 93 – 97: I cannot follow the hypothesis here: if gross N mineralization, microbial and root biomass have been observed to be the same between the two management treatments, why would the authors expect a decrease in N2O emissions? And at the same time no change in CO2 and CH4?

Material & Methods

The definition of the management zones is not entirely clear to me: The palm circle was the area between the palm trees, but within the fertilized and managed area. How close to the trees were the measurements made? Was root respiration included? I assume that the fronds have been removed before measuring in the frond-stacked area? When has this happened? Only during the measurements or have they been removed constantly?

l. 143: 0.02 m appears to be a very shallow depth for GHG measurements and usually, a depth of 0.01 m (i.e., 10 cm) is recommended. How high were the bases and why was this depth chosen?

Results

l. 249: each = any of the (?)

Discussion

l. 276: if SOC, microbial and root biomass were explanatory for soil CO2 fluxes, this should be presented in the results already. In fact, the following lines until l. 282 should be moved to the Results section – also, as this supports one of the hypotheses

l. 336: reduced

l. 340: remove “possibly” – the authors provide the explanation in the following sentence

l. 342 – 344: I don´t understand why the this should be a result of decadal over-fertilization – in this study, the authors used higher amounts if fertilizer than used in smallholder oil palm plantations (this is mentioned in ll. 336 – 337). It should thus not be considered a legacy effect of past fertilization management

l. 346: lasting effects on what?

l. 354 – 356: why this comparison? I would think that a plantation cannot be considered a forest

l. 396: please repeat the GWP obtained in this study

Conclusion

l. 429 – 431: I don´t think that this is a legacy effects – the fertilization is still rather high