|In the current revision, Liu et al. have addressed most of my concerns in last referee report. Particularly, they reorganized the structure of the whole manuscript and raised specific scientific question as suggested before. Nevertheless, I am still not satisfied with the manner of writing of Introduction and Discussion, especially their language issues which were mentioned in last report. In Introduction, the first two paragraphs employed many references to underline the water cycle of SPAC and the advantages of stable isotopes. I suggest the authors to focus the scientific question and make it more specific. In Discussion, e.g., 4.22, the authors presented mainly the complete results, but they didn’t try to generalize the drivers and mechanisms behind the data, and no previous studies were listed and compared with each other. In addition, I still have some specific comments.|
L14: Replace “studied” with “investigated” or other words.
L15: Delete “soil-plant-atmosphere continuum”.
L28: Delete “in water technology”.
L41-44: I suggest the authors to modify this sentence as “As an effective tool, stable isotope technology is widely applied in studying…, and tracing the way plants use water…”.
L49: Delete “stable”, “methods”.
L51: Modify this sentence to be specific, what the parameters are.
L63: Delete “of water”.
L61-66: Please rearrange this long sentence, especially the content after “such as”. “…in western China”?
L67: “…extend the results of the small-scale…”.
L68: Delete “in the current research”.
L69: I think that the stable isotope technology is not much new in studying SPAC.
L74-76: Although the isotope ratio in soil water changes with depth, it remains stable when transporting from plant roots to stems, leaves or young unbolted branches.
L89-90: “…runoff regeneration, groundwater recharge and regeneration capacity can be determined”.
L93: What is “it”? “…studying the mechanism of the deep water cycle”.
L94: “…plants transpiration”.
L125: “…better than that of lower reaches…”.
L148: “xylem stem” should be “stem”.
L158: “…and used…”.
L159-162: Please standardize the font of “δ” throughout the manuscript.
L163: “modify” to “calibrate”.
L175: “…normally distributed…”?
L202: “The slope of LMWL…”.
L215-224: As I understand, the current paragraph is only about oxygen isotope. Is it right? So it should be “stable oxygen isotope” since L215.
L216: I suggest the authors use δ18O and δD in manuscript instead of “water isotope value”.
L227: “…plant water isotope…”.
L238: “…the current experiment is divided into…”.
L240: “…have the highest value of δ18O (-2.84‰)”.
L251: What’s the meaning of “soil underwater infiltrates the groundwater”?
L259: “…plant water oxygen is the most enriched…”.
L262: “meters” to “m”. “burial” to “table”.
L266: “…soil water isotope”.
L270: “… (-0.15), while that of the forest…”.
Fig. 2: Relative humidity.
Fig. 4 and Fig. 5: Add “(m)” after “Soil depth” and delete “m” along the Y-axis.
Fig. 8: Please standardize the font size. “absoult” should be “absolute”?