Dear Prof. Lv,

Thank you for submitting your revised ms to BG.

The comments have been adequately addressed and there are only few minor concerns for your attention before publication.
(1) The title. Carbon and nitrogen storage is an appropriate term for the bulk soil as a whole. But it seems for me that carbon and nitrogen content is often used when it refers to particle-size fraction. Therefore, I am not sure whether carbon and nitrogen stock is better than the term storage. pls consult soil chemist for this matter. I think the concentration or content is better than stock.
(2) The mechanisms behind the decreasing carbon and nitrogen content along increasing aridity. This observation might be a net result of lower above-ground biomass under higher aridity over a geological timescale. It could also result in higher content of sand component in temperate steppe.

Yours sincerely

Zhongjun Jia

Dear Prof. Lv

Thank you for submitting a revised version of your manuscript to BG.

The comments have been adequately addressed, and it can be accepted for publication.

Yours Sincerely

Zhongjun Jia