TY - JOUR
T1 - Effects of rainfall manipulations on carbon exchange of cyanobacteria and moss-dominated biological soil crusts
AU - Zhang, Chunping
AU - Niu, Decao
AU - Song, Meiling
AU - Elser, James
AU - Okie, Jordan
AU - Fu, Hua
N1 - Funding Information:
This study was supported by National Key R&D Program of China ( 2016YFC0500506 ), National Natural Science Foundation of China ( 31572458 , 31201837 , 41671106 , and 31772655 ), Natural Science Foundation of Qinghai Province ( 2017-ZJ-948Q ), the Fundamental Research Funds for the Central Universities ( lzujbky-2017-47 ), the Program for Changjiang Scholars and Innovative Research Team in University ( IRT_17R50 ) and the 111 project ( B12002 ). The authors are grateful to Xudong Li and Ding Guo for revising the paper and to the Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL) for supporting the field work.
Publisher Copyright:
© 2018 Elsevier Ltd
PY - 2018/9
Y1 - 2018/9
N2 - Biological soil crusts (biocrusts) are a vital biotic component of dryland ecosystems that impact global nitrogen (N) and carbon (C) cycling. Water availability is the main controller of physiological function of biocrusts in these ecosystems, yet few studies have compared the carbon balance of different biocrusts responding to different water treatments. In this study, we explored the effects of water availability on carbon exchanges of different biocrusts by measuring in situ net CO2 fluxes in cyanobacteria and moss-dominated biocrusts under four water treatments (2 mm, 5 mm, 10 mm, and 20 mm) in a fenced grassland on the Loess Plateau, China. Our results indicate that water availability played a vital role in carbon balance of the biocrusts. Under higher water additions, both cyanobacteria and moss-dominated biocrusts fixed carbon but lower water additions did not always lead to net carbon gains, especially for the moss-dominated crusts. Importantly, our data indicate the existence of water thresholds for net carbon fixation of both cyanobacteria and moss-dominated biocrusts, below which carbon loss occurs. This implies that higher water availability would benefit moss growth, while lower water availability results in suitable circumstance for the growth of cyanobacteria.
AB - Biological soil crusts (biocrusts) are a vital biotic component of dryland ecosystems that impact global nitrogen (N) and carbon (C) cycling. Water availability is the main controller of physiological function of biocrusts in these ecosystems, yet few studies have compared the carbon balance of different biocrusts responding to different water treatments. In this study, we explored the effects of water availability on carbon exchanges of different biocrusts by measuring in situ net CO2 fluxes in cyanobacteria and moss-dominated biocrusts under four water treatments (2 mm, 5 mm, 10 mm, and 20 mm) in a fenced grassland on the Loess Plateau, China. Our results indicate that water availability played a vital role in carbon balance of the biocrusts. Under higher water additions, both cyanobacteria and moss-dominated biocrusts fixed carbon but lower water additions did not always lead to net carbon gains, especially for the moss-dominated crusts. Importantly, our data indicate the existence of water thresholds for net carbon fixation of both cyanobacteria and moss-dominated biocrusts, below which carbon loss occurs. This implies that higher water availability would benefit moss growth, while lower water availability results in suitable circumstance for the growth of cyanobacteria.
KW - Biocrusts
KW - Carbon balance
KW - Semi-arid region
KW - Water addition
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U2 - 10.1016/j.soilbio.2018.05.021
DO - 10.1016/j.soilbio.2018.05.021
M3 - Article
AN - SCOPUS:85047508401
SN - 0038-0717
VL - 124
SP - 24
EP - 31
JO - Soil Biology and Biochemistry
JF - Soil Biology and Biochemistry
ER -