TY - JOUR

T1 - Potential feedback mediated by soil microbiome response to warming in a glacier forefield

AU - Wang, Yuwan

AU - Ma, Anzhou

AU - Liu, Guohua

AU - Ma, Jianpeng

AU - Wei, Jing

AU - Zhou, Hanchang

AU - Brandt, Kristian Koefoed

AU - Zhuang, Guoqiang

PY - 2020

Y1 - 2020

N2 - Mountain glaciers are retreating at an unprecedented rate due to global warming. Glacier retreat is widely believed to be driven by the physiochemical characteristics of glacier surfaces; however, the current knowledge of such biological drivers remains limited. An estimated 130 Tg of organic carbon (OC) is stored in mountain glaciers globally. As a result of global warming, the accelerated microbial decomposition of OC may further accelerate the melting process of mountain glaciers by heat production with the release of greenhouse gases, such as carbon dioxide (CO2) and methane. Here, using short-term aerobic incubation data from the forefield of Urumqi Glacier No. 1, we assessed the potential climate feedback mediated by soil microbiomes at temperatures of 5°C (control), 6.2°C (RCP 2.6), 11°C (RCP 8.5), and 15°C (extreme temperature). We observed enhanced CO2-C release and heat production under warming conditions, which led to an increase in near-surface (2 m) atmospheric temperatures, ranging from 0.9°C to 3.4°C. Warming significantly changed the structures of the RNA-derived (active) and DNA-derived (total) soil microbiomes, and active microbes were more sensitive to increased temperatures than total microbes. Considering the positive effects of temperature and deglaciation age on the CO2-C release rate, the alterations in the active microbial community structure had a negative impact on the increased CO2-C release rate. Our results revealed that glacial melting could potentially be significantly accelerated by heat production from increased microbial decomposition of OC. This risk might be true for other high-altitude glaciers under emerging warming, thus improving the predictions of the effects of potential feedback on global warming.

AB - Mountain glaciers are retreating at an unprecedented rate due to global warming. Glacier retreat is widely believed to be driven by the physiochemical characteristics of glacier surfaces; however, the current knowledge of such biological drivers remains limited. An estimated 130 Tg of organic carbon (OC) is stored in mountain glaciers globally. As a result of global warming, the accelerated microbial decomposition of OC may further accelerate the melting process of mountain glaciers by heat production with the release of greenhouse gases, such as carbon dioxide (CO2) and methane. Here, using short-term aerobic incubation data from the forefield of Urumqi Glacier No. 1, we assessed the potential climate feedback mediated by soil microbiomes at temperatures of 5°C (control), 6.2°C (RCP 2.6), 11°C (RCP 8.5), and 15°C (extreme temperature). We observed enhanced CO2-C release and heat production under warming conditions, which led to an increase in near-surface (2 m) atmospheric temperatures, ranging from 0.9°C to 3.4°C. Warming significantly changed the structures of the RNA-derived (active) and DNA-derived (total) soil microbiomes, and active microbes were more sensitive to increased temperatures than total microbes. Considering the positive effects of temperature and deglaciation age on the CO2-C release rate, the alterations in the active microbial community structure had a negative impact on the increased CO2-C release rate. Our results revealed that glacial melting could potentially be significantly accelerated by heat production from increased microbial decomposition of OC. This risk might be true for other high-altitude glaciers under emerging warming, thus improving the predictions of the effects of potential feedback on global warming.

KW - CO-C release

KW - feedback

KW - glacier forefield

KW - global warming

KW - heat production

KW - soil microbiome

U2 - 10.1111/gcb.14936

DO - 10.1111/gcb.14936

M3 - Journal article

C2 - 31782204

AN - SCOPUS:85077362723

VL - 26

SP - 697

EP - 708

JO - Global Change Biology

JF - Global Change Biology

SN - 1354-1013

IS - 2

ER -