土壤学报2025，Vol.62Issue(3)：665-676,12.DOI:10.11766/trxb202402070064
基于DNDC模型评估极端高温和长期变暖对水田土壤有机碳的影响
Assessing the Impacts of Extreme High Temperatures and Long-term Warming on Paddy Soil Organic Carbon Based on the DNDC Model-A Case Study in Zhangzhou of Fujian Province
摘要
Abstract
[Objective]Soil organic carbon(SOC)is an essential indicator of soil health.It not only provides a carbon source for plant growth and maintains the physical structure of soil,but also releases carbon into the atmosphere in the form of greenhouse gases,such as carbon dioxide.Therefore,it plays a critical role in the global carbon balance.Currently,the world is experiencing climate change characterized predominantly by warming and increasing frequency and intensity of extreme weather events.However,the impacts of the changing climate,including long-term warming and extreme weather events on SOC are not entirely the same.Distinguishing and quantifying the effects of extremely high temperatures(EH)and long-term warming(LW)on SOC is the key to formulating adaptive strategies.[Method]In this study,we focused on paddy soils in Zhangzhou of Fujian Province,a typical subtropical region of China.Based on a 1︰50,000 detailed soil database,we employed the biogeochemical process model(DeNitrification-DeComposition,DNDC)to simulate SOC dynamics under four climate scenarios:de-trended climate base state(CTRL),extreme high temperatures(EXP_EH),long-term warming(EXP_LW),and measured temperatures(EXP_obs).[Result]The results revealed that the total amount of carbon sequestered by paddy fields in Zhangzhou from 1980 to 2016 under the four different climate scenarios(CTRL,EXP_EH,EXP_LW,and EXP_obs)was 1,032.17,952.15,1,045.98 and 966.03 Gg,with the corresponding average annual sequestration rates of 93.98,86.70,95.24,and 87.96 kg·hm-2,respectively.The long-term warming led to a net increase of 13.81 Gg of SOC in paddy fields across Zhangzhou,while extremely high temperatures resulted in a net decrease of 80.02 Gg.The combined effect of these two factors was-66.14 Gg in SOC,indicating that long-term warming promoted the sequestration of organic carbon in paddy soils,while extremely high temperatures reduced the soil carbon sink capacity,with extremely high temperatures exerting a dominant negative effect.Also,the variations in annual carbon sequestration rates between different climate scenarios indicated that extremely high temperatures throughout the years from 1980 to 2016 had a negative effect on carbon sequestration in the paddy soils of Zhangzhou,but the long-term warming effect on SOC turned from positive to negative around the year of 2000.This may be related to the diminishing effect of warming on plant growth over time.At the county level,climate change had the greatest impact on the carbon sequestration of Nanjing County.Additionally,the extremely high temperatures and long-term warming caused-26.23%and 7.27%impacts on its carbon sequestration rate,respectively.Furthermore,among different terrain and topographical areas,the carbon sequestration rate of hilly and mountainous areas was significantly affected by extremely high temperatures and long-term warming,with-8.84%and 1.98%changes,respectively.[Conclusion]In conclusion,while the paddy soils in Zhangzhou still maintain a strong carbon sequestration capacity in the context of climate change,the increasing extreme high-temperature events in the future may potentially contribute to greater carbon losses to some extent.关键词
DNDC模型/长期变暖/极端高温/土壤有机碳/水稻土Key words
DNDC model/Long-term warming/Extreme high temperatures/Soil organic carbon/Paddy soils分类
农业科技引用本文复制引用
李晶,陈伟明,孙佳蕊,谢希临,张华,沈金泉,廖文强,邢世和,张黎明..基于DNDC模型评估极端高温和长期变暖对水田土壤有机碳的影响[J].土壤学报,2025,62(3):665-676,12.基金项目
国家自然科学基金项目(42207271)、福建省自然科学基金项目(2022J05036)和气象灾害教育部重点实验室&气象灾害预报预警与评估协同创新中心联合开放课题(KLME202105)共同资助 Supported by the National Natural Science Foundation of China(No.42207271),the Natural Science Foundation of Fujian Province(No.2022J05036),and the Joint Open Project Program of the Key Laboratory of Meteorological Disaster,Ministry of Education&Collaborative Innovation Center on Forecast and Evaluation of （42207271）
