Lower Sensitivity of Soil Carbon and Nitrogen to Regional Temperature Change in Karst Forests Than in Non-Karst Forests

Lithology has such an important effect on the sustainability of soil carbon (C) pools. Forests are an important part of terrestrial C sinks; yet, it is unclear whether their soil carbon sensitivity to temperature changes is regulated by lithology, especially in karst ecosystems, which are widely dis...

Full description

Bibliographic Details
Main Authors: Yunfan Li, Rong Yang, Peilei Hu, Dan Xiao, Zhongcheng Wang, Wei Zhang, Kelin Wang
Format: Article
Language:English
Published: MDPI AG 2023-02-01
Series:Forests
Subjects:
Online Access:https://www.mdpi.com/1999-4907/14/2/355
_version_ 1797620981483700224
author Yunfan Li
Rong Yang
Peilei Hu
Dan Xiao
Zhongcheng Wang
Wei Zhang
Kelin Wang
author_facet Yunfan Li
Rong Yang
Peilei Hu
Dan Xiao
Zhongcheng Wang
Wei Zhang
Kelin Wang
author_sort Yunfan Li
collection DOAJ
description Lithology has such an important effect on the sustainability of soil carbon (C) pools. Forests are an important part of terrestrial C sinks; yet, it is unclear whether their soil carbon sensitivity to temperature changes is regulated by lithology, especially in karst ecosystems, which are widely distributed globally. Along a climate gradient in the subtropical region of southwest China, we compared the contents of soil organic C (SOC) and total N (TN) in karst and non-karst forests. The data were analyzed and processed using ANOVA, regression analysis, and random forest. The results showed that the karst forests had significantly higher SOC and TN contents but lower ratio of SOC to TN (C:N) than non-karst forests, mainly because of the higher soil calcium (Ca) content and microbial biomass. With rising mean annual temperature (MAT), SOC and TN contents in non-karst forests significantly decreased, whereas in karst forests they were not correlated with MAT; while, the opposite was true for C:N. In karst forests, soil Ca constrain warming induced decomposition of SOC and TN by forming stable complexes with SOM through exchangeable Ca, and by promoting aggregate stability through the role of calcium carbonate. The correlation between δ<sup>13</sup>C and the logarithm of SOC concentration also supported that conclusion. In karst forests compared to non-karst forests, soil C pools are larger and less sensitive to regional temperature change. Nevertheless, climate warming may still accelerate soil C loss in karst forests by increasing microbial C limitation. Thus, soil C sequestration potential and loss risk coexist in karst areas. The ratio of SOC to TN (C:N) is regulated through appropriate management measures in the process of karst vegetation restoration, thus promoting long-term stable sequestration of soil carbon pools.
first_indexed 2024-03-11T08:49:14Z
format Article
id doaj.art-cccabdc6eb824f0da4dfb2e3bb444307
institution Directory Open Access Journal
issn 1999-4907
language English
last_indexed 2024-03-11T08:49:14Z
publishDate 2023-02-01
publisher MDPI AG
record_format Article
series Forests
spelling doaj.art-cccabdc6eb824f0da4dfb2e3bb4443072023-11-16T20:34:50ZengMDPI AGForests1999-49072023-02-0114235510.3390/f14020355Lower Sensitivity of Soil Carbon and Nitrogen to Regional Temperature Change in Karst Forests Than in Non-Karst ForestsYunfan Li0Rong Yang1Peilei Hu2Dan Xiao3Zhongcheng Wang4Wei Zhang5Kelin Wang6Forestry College, Central South University of Forestry and Technology, Changsha 410004, ChinaUniversity of Chinese Academy of Sciences, Beijing 100049, ChinaKey Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, ChinaKey Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, ChinaForestry College, Central South University of Forestry and Technology, Changsha 410004, ChinaKey Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, ChinaKey Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, ChinaLithology has such an important effect on the sustainability of soil carbon (C) pools. Forests are an important part of terrestrial C sinks; yet, it is unclear whether their soil carbon sensitivity to temperature changes is regulated by lithology, especially in karst ecosystems, which are widely distributed globally. Along a climate gradient in the subtropical region of southwest China, we compared the contents of soil organic C (SOC) and total N (TN) in karst and non-karst forests. The data were analyzed and processed using ANOVA, regression analysis, and random forest. The results showed that the karst forests had significantly higher SOC and TN contents but lower ratio of SOC to TN (C:N) than non-karst forests, mainly because of the higher soil calcium (Ca) content and microbial biomass. With rising mean annual temperature (MAT), SOC and TN contents in non-karst forests significantly decreased, whereas in karst forests they were not correlated with MAT; while, the opposite was true for C:N. In karst forests, soil Ca constrain warming induced decomposition of SOC and TN by forming stable complexes with SOM through exchangeable Ca, and by promoting aggregate stability through the role of calcium carbonate. The correlation between δ<sup>13</sup>C and the logarithm of SOC concentration also supported that conclusion. In karst forests compared to non-karst forests, soil C pools are larger and less sensitive to regional temperature change. Nevertheless, climate warming may still accelerate soil C loss in karst forests by increasing microbial C limitation. Thus, soil C sequestration potential and loss risk coexist in karst areas. The ratio of SOC to TN (C:N) is regulated through appropriate management measures in the process of karst vegetation restoration, thus promoting long-term stable sequestration of soil carbon pools.https://www.mdpi.com/1999-4907/14/2/355climate warmingcalciumKarst ecosystemslithologysoil organic matter
spellingShingle Yunfan Li
Rong Yang
Peilei Hu
Dan Xiao
Zhongcheng Wang
Wei Zhang
Kelin Wang
Lower Sensitivity of Soil Carbon and Nitrogen to Regional Temperature Change in Karst Forests Than in Non-Karst Forests
Forests
climate warming
calcium
Karst ecosystems
lithology
soil organic matter
title Lower Sensitivity of Soil Carbon and Nitrogen to Regional Temperature Change in Karst Forests Than in Non-Karst Forests
title_full Lower Sensitivity of Soil Carbon and Nitrogen to Regional Temperature Change in Karst Forests Than in Non-Karst Forests
title_fullStr Lower Sensitivity of Soil Carbon and Nitrogen to Regional Temperature Change in Karst Forests Than in Non-Karst Forests
title_full_unstemmed Lower Sensitivity of Soil Carbon and Nitrogen to Regional Temperature Change in Karst Forests Than in Non-Karst Forests
title_short Lower Sensitivity of Soil Carbon and Nitrogen to Regional Temperature Change in Karst Forests Than in Non-Karst Forests
title_sort lower sensitivity of soil carbon and nitrogen to regional temperature change in karst forests than in non karst forests
topic climate warming
calcium
Karst ecosystems
lithology
soil organic matter
url https://www.mdpi.com/1999-4907/14/2/355
work_keys_str_mv AT yunfanli lowersensitivityofsoilcarbonandnitrogentoregionaltemperaturechangeinkarstforeststhaninnonkarstforests
AT rongyang lowersensitivityofsoilcarbonandnitrogentoregionaltemperaturechangeinkarstforeststhaninnonkarstforests
AT peileihu lowersensitivityofsoilcarbonandnitrogentoregionaltemperaturechangeinkarstforeststhaninnonkarstforests
AT danxiao lowersensitivityofsoilcarbonandnitrogentoregionaltemperaturechangeinkarstforeststhaninnonkarstforests
AT zhongchengwang lowersensitivityofsoilcarbonandnitrogentoregionaltemperaturechangeinkarstforeststhaninnonkarstforests
AT weizhang lowersensitivityofsoilcarbonandnitrogentoregionaltemperaturechangeinkarstforeststhaninnonkarstforests
AT kelinwang lowersensitivityofsoilcarbonandnitrogentoregionaltemperaturechangeinkarstforeststhaninnonkarstforests