Trajectory of Topsoil Nitrogen Transformations Along a Thermo-Erosion Gully on the Tibetan Plateau
Permafrost thaw, especially thermokarst formation, that is, ground collapse due to thawing of ice-rich permafrost, is expected to alter soil gross nitrogen (N) transformations, which can regulate plant productivity and ecosystem carbon cycle. However, it remains unclear how thermokarst formation mod...
Published in: | Journal of Geophysical Research: Biogeosciences |
---|---|
Main Authors: | , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
AMER GEOPHYSICAL UNION
2019
|
Subjects: | |
Online Access: | http://ir.ibcas.ac.cn/handle/2S10CLM1/19460 https://doi.org/10.1029/2018JG004805 |
id |
ftchiacadscibcas:oai:ir.ibcas.ac.cn:2S10CLM1/19460 |
---|---|
record_format |
openpolar |
spelling |
ftchiacadscibcas:oai:ir.ibcas.ac.cn:2S10CLM1/19460 2023-05-15T16:37:13+02:00 Trajectory of Topsoil Nitrogen Transformations Along a Thermo-Erosion Gully on the Tibetan Plateau Mao, Chao Kou, Dan Wang, Guanqin Peng, Yunfeng Yang, Guibiao Liu, Futing Zhang, Jinbo Yang, Yuanhe 2019 http://ir.ibcas.ac.cn/handle/2S10CLM1/19460 https://doi.org/10.1029/2018JG004805 英语 eng AMER GEOPHYSICAL UNION JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES http://ir.ibcas.ac.cn/handle/2S10CLM1/19460 doi:10.1029/2018JG004805 cn.org.cspace.api.content.CopyrightPolicy@20b1f812 carbon-nitrogen interactions gross nitrogen mineralization gross nitrification microbial nitrogen limitation permafrost thaw thermokarst Environmental Sciences Geosciences Multidisciplinary AMMONIA-OXIDIZING BACTERIA PERMAFROST CARBON MICROBIAL COMMUNITY EXTRACTION METHOD SOIL FOREST DYNAMICS AVAILABILITY INCREASES PRODUCTIVITY Environmental Sciences & Ecology Geology Article 期刊论文 2019 ftchiacadscibcas https://doi.org/10.1029/2018JG004805 2022-06-12T18:13:47Z Permafrost thaw, especially thermokarst formation, that is, ground collapse due to thawing of ice-rich permafrost, is expected to alter soil gross nitrogen (N) transformations, which can regulate plant productivity and ecosystem carbon cycle. However, it remains unclear how thermokarst formation modifies soil N processes in permafrost ecosystems. Here N-15 pool dilution techniques were used to evaluate changes in topsoil gross N transformations during various thaw stages (early, middle, and late stages) along a thermo-erosion gully on the Tibetan Plateau. Structural equation modeling was then conducted to explore the relative importance of biotic and abiotic factors in affecting soil gross N transformations. The results showed that topsoil gross N mineralization (GNM) decreased at the three stages, reflecting declined inorganic N production after permafrost collapse. In contrast, topsoil gross nitrification increased only during the early stage. Additionally, the ratio of microbial N immobilization to GNM was enhanced during the middle and late stages, indicating a stronger microbial N limitation after thermokarst formation. The structural equation modeling analysis revealed that soil moisture played an important role in modulating gross N transformations. For GNM, decreased soil moisture had inhibiting effects via regulating the microbial biomass, microbial community, and enzyme activities along the thaw sequence. For gross nitrification, declined soil moisture exerted facilitating effects directly by improving oxygen availability and indirectly by modulating the abundances of ammonia-oxidizing archaea and bacteria during the early stage. Overall, these results demonstrated that thermokarst formation altered soil N processes, potentially triggering interactions between ecosystem N and carbon cycles after permafrost thaw. Article in Journal/Newspaper Ice permafrost Thermokarst Institute of Botany: IBCAS OpenIR (Chinese Academy Of Sciences) Journal of Geophysical Research: Biogeosciences 124 5 1342 1354 |
institution |
Open Polar |
collection |
Institute of Botany: IBCAS OpenIR (Chinese Academy Of Sciences) |
op_collection_id |
ftchiacadscibcas |
language |
English |
topic |
carbon-nitrogen interactions gross nitrogen mineralization gross nitrification microbial nitrogen limitation permafrost thaw thermokarst Environmental Sciences Geosciences Multidisciplinary AMMONIA-OXIDIZING BACTERIA PERMAFROST CARBON MICROBIAL COMMUNITY EXTRACTION METHOD SOIL FOREST DYNAMICS AVAILABILITY INCREASES PRODUCTIVITY Environmental Sciences & Ecology Geology |
spellingShingle |
carbon-nitrogen interactions gross nitrogen mineralization gross nitrification microbial nitrogen limitation permafrost thaw thermokarst Environmental Sciences Geosciences Multidisciplinary AMMONIA-OXIDIZING BACTERIA PERMAFROST CARBON MICROBIAL COMMUNITY EXTRACTION METHOD SOIL FOREST DYNAMICS AVAILABILITY INCREASES PRODUCTIVITY Environmental Sciences & Ecology Geology Mao, Chao Kou, Dan Wang, Guanqin Peng, Yunfeng Yang, Guibiao Liu, Futing Zhang, Jinbo Yang, Yuanhe Trajectory of Topsoil Nitrogen Transformations Along a Thermo-Erosion Gully on the Tibetan Plateau |
topic_facet |
carbon-nitrogen interactions gross nitrogen mineralization gross nitrification microbial nitrogen limitation permafrost thaw thermokarst Environmental Sciences Geosciences Multidisciplinary AMMONIA-OXIDIZING BACTERIA PERMAFROST CARBON MICROBIAL COMMUNITY EXTRACTION METHOD SOIL FOREST DYNAMICS AVAILABILITY INCREASES PRODUCTIVITY Environmental Sciences & Ecology Geology |
description |
Permafrost thaw, especially thermokarst formation, that is, ground collapse due to thawing of ice-rich permafrost, is expected to alter soil gross nitrogen (N) transformations, which can regulate plant productivity and ecosystem carbon cycle. However, it remains unclear how thermokarst formation modifies soil N processes in permafrost ecosystems. Here N-15 pool dilution techniques were used to evaluate changes in topsoil gross N transformations during various thaw stages (early, middle, and late stages) along a thermo-erosion gully on the Tibetan Plateau. Structural equation modeling was then conducted to explore the relative importance of biotic and abiotic factors in affecting soil gross N transformations. The results showed that topsoil gross N mineralization (GNM) decreased at the three stages, reflecting declined inorganic N production after permafrost collapse. In contrast, topsoil gross nitrification increased only during the early stage. Additionally, the ratio of microbial N immobilization to GNM was enhanced during the middle and late stages, indicating a stronger microbial N limitation after thermokarst formation. The structural equation modeling analysis revealed that soil moisture played an important role in modulating gross N transformations. For GNM, decreased soil moisture had inhibiting effects via regulating the microbial biomass, microbial community, and enzyme activities along the thaw sequence. For gross nitrification, declined soil moisture exerted facilitating effects directly by improving oxygen availability and indirectly by modulating the abundances of ammonia-oxidizing archaea and bacteria during the early stage. Overall, these results demonstrated that thermokarst formation altered soil N processes, potentially triggering interactions between ecosystem N and carbon cycles after permafrost thaw. |
format |
Article in Journal/Newspaper |
author |
Mao, Chao Kou, Dan Wang, Guanqin Peng, Yunfeng Yang, Guibiao Liu, Futing Zhang, Jinbo Yang, Yuanhe |
author_facet |
Mao, Chao Kou, Dan Wang, Guanqin Peng, Yunfeng Yang, Guibiao Liu, Futing Zhang, Jinbo Yang, Yuanhe |
author_sort |
Mao, Chao |
title |
Trajectory of Topsoil Nitrogen Transformations Along a Thermo-Erosion Gully on the Tibetan Plateau |
title_short |
Trajectory of Topsoil Nitrogen Transformations Along a Thermo-Erosion Gully on the Tibetan Plateau |
title_full |
Trajectory of Topsoil Nitrogen Transformations Along a Thermo-Erosion Gully on the Tibetan Plateau |
title_fullStr |
Trajectory of Topsoil Nitrogen Transformations Along a Thermo-Erosion Gully on the Tibetan Plateau |
title_full_unstemmed |
Trajectory of Topsoil Nitrogen Transformations Along a Thermo-Erosion Gully on the Tibetan Plateau |
title_sort |
trajectory of topsoil nitrogen transformations along a thermo-erosion gully on the tibetan plateau |
publisher |
AMER GEOPHYSICAL UNION |
publishDate |
2019 |
url |
http://ir.ibcas.ac.cn/handle/2S10CLM1/19460 https://doi.org/10.1029/2018JG004805 |
genre |
Ice permafrost Thermokarst |
genre_facet |
Ice permafrost Thermokarst |
op_relation |
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES http://ir.ibcas.ac.cn/handle/2S10CLM1/19460 doi:10.1029/2018JG004805 |
op_rights |
cn.org.cspace.api.content.CopyrightPolicy@20b1f812 |
op_doi |
https://doi.org/10.1029/2018JG004805 |
container_title |
Journal of Geophysical Research: Biogeosciences |
container_volume |
124 |
container_issue |
5 |
container_start_page |
1342 |
op_container_end_page |
1354 |
_version_ |
1766027513942769664 |