AUTHOR=Zhang Dongjie , Wang Hui , Liu Xuepeng , Ao Kang , He Wenjun , Wang Tongxin , Zhang Mingye , Tong Shouzheng 

TITLE=Latitudinal patterns and their climate drivers of the δ13C, δ15N, δ34S isotope signatures of Spartina alterniflora across plant life-death status: a global analysis

JOURNAL=Frontiers in Plant Science

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2024.1384914

DOI=10.3389/fpls.2024.1384914

ISSN=1664-462X

ABSTRACT=<p>Isotopic signatures offer new methods, approaches, and perspectives for exploring the ecological adaptability and functions of plants. We examined pattern differences in the isotopic signatures (<italic>δ</italic><sup>13</sup>C, <italic>δ</italic><sup>15</sup>N, <italic>δ</italic><sup>34</sup>S) of <italic>Spartina alterniflora</italic> across varying plant life-death status along geographic clines. We extracted 539 sets of isotopic data from 57 publications covering 267 sites across a latitude range of over 23.8° along coastal wetlands. Responses of isotopic signatures to climate drivers (MAT and MAP) and the internal relationships between isotopic signatures were also detected. Results showed that the <italic>δ</italic><sup>13</sup>C, <italic>δ</italic><sup>15</sup>N, and <italic>δ</italic><sup>34</sup>S of <italic>S. alterniflora</italic> were -13.52 ± 0.83‰, 6.16 ± 0.14‰, and 4.01 ± 6.96‰, with a range of -17.44‰ to -11.00‰, -2.40‰ to 15.30‰, and -9.60‰ to 15.80‰, respectively. The latitudinal patterns of <italic>δ</italic><sup>13</sup>C, <italic>δ</italic><sup>15</sup>N, and <italic>δ</italic><sup>34</sup>S in <italic>S. alterniflora</italic> were shaped as a convex curve, a concave curve, and an increasing straight line, respectively. A decreasing straight line for <italic>δ</italic><sup>13</sup>C within the ranges of MAT was identified under plant life status. Plant life-death status shaped two nearly parallel decreasing straight lines for <italic>δ</italic><sup>34</sup>S in response to MAT, resulting in a concave curve of <italic>δ</italic><sup>34</sup>S for live <italic>S. alterniflora</italic> in response to MAP. The <italic>δ</italic><sup>15</sup>N of <italic>S. alterniflora</italic> significantly decreased with increasing <italic>δ</italic><sup>13</sup>C of <italic>S. alterniflora</italic>, except for plant death status. The <italic>δ</italic><sup>13</sup>C, <italic>δ</italic><sup>15</sup>N, and <italic>δ</italic><sup>34</sup>S of <italic>S</italic>. <italic>alterniflora</italic> are consistent with plant height, stem diameter, leaf traits, etc, showing general latitudinal patterns closely related to MAT. Plant life-death status altered the <italic>δ</italic><sup>15</sup>N (live: 6.55 ± 2.23‰; dead: -2.76 ± 2.72‰), latitudinal patterns of <italic>S</italic>. <italic>alterniflora</italic> and their responses to MAT, demonstrating strong ecological plasticity and adaptability across the geographic clines. The findings help in understanding the responses of latitudinal patterns of the <italic>δ</italic><sup>13</sup>C, <italic>δ</italic><sup>15</sup>N, and <italic>δ</italic><sup>34</sup>S isotope signatures of <italic>S. alterniflora</italic> in response plant life-death status, and provide evidence of robust ecological plasticity and adaptability across geographic clines.</p>