{"title":"Soil net carbon balance depends on soil C: N: P stoichiometry","authors":"","doi":"10.1016/j.still.2024.106298","DOIUrl":null,"url":null,"abstract":"<div><p>Exogenous carbon (C) input may induce priming effects, leading to the loss of soil organic C (SOC) by accelerating the decomposition of native soil organic matter (SOM), while also replenishing SOC through various mechanisms. However, the net C balance resulting from priming and replenishment of SOC under long-term nitrogen (N) fertilization and its stoichiometric regulation mechanisms remain largely undetermined. Soils subjected to 11 years of different N applications were used to investigate the net C balance following the addition of exogenous <sup>13</sup>C-labeled glucose. The retention of glucose-derived C exceeded the loss of C caused by the priming effect, resulting in a positive net C balance, albeit attenuated by historical N application (ranging from 25.9 to 36.9 μg C mg<sup>−1</sup> SOC). The application of increasing historical N levels resulted in a decrease in soil C:N imbalance and an increase in soil N:phosphorus (P) imbalance, as well as an increase in TER<sub>C:N</sub> and TER<sub>C:P</sub>. This suggested that the C and/or P limitations of soil microbial communities were intensified with increased N availability. Soil nutrient stoichiometric imbalance and available resource stoichiometry directly influenced the threshold element ratio, which in turn impacted glucose mineralization, subsequently affecting the net C balance. Collectively, our results provided solid evidence that labile C input could lead to a positive net C balance, which diminished with increased historical N application and was primarily regulated by soil C:N:P stoichiometry. This study highlights the significant implications for the soil C turnover and sequestration under long-term N application management in agroecosystems.</p></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":null,"pages":null},"PeriodicalIF":6.1000,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S016719872400299X/pdfft?md5=a35f247b2d3ee2dfe1e0c2a8adbb7e32&pid=1-s2.0-S016719872400299X-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Soil & Tillage Research","FirstCategoryId":"97","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S016719872400299X","RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"SOIL SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
Exogenous carbon (C) input may induce priming effects, leading to the loss of soil organic C (SOC) by accelerating the decomposition of native soil organic matter (SOM), while also replenishing SOC through various mechanisms. However, the net C balance resulting from priming and replenishment of SOC under long-term nitrogen (N) fertilization and its stoichiometric regulation mechanisms remain largely undetermined. Soils subjected to 11 years of different N applications were used to investigate the net C balance following the addition of exogenous 13C-labeled glucose. The retention of glucose-derived C exceeded the loss of C caused by the priming effect, resulting in a positive net C balance, albeit attenuated by historical N application (ranging from 25.9 to 36.9 μg C mg−1 SOC). The application of increasing historical N levels resulted in a decrease in soil C:N imbalance and an increase in soil N:phosphorus (P) imbalance, as well as an increase in TERC:N and TERC:P. This suggested that the C and/or P limitations of soil microbial communities were intensified with increased N availability. Soil nutrient stoichiometric imbalance and available resource stoichiometry directly influenced the threshold element ratio, which in turn impacted glucose mineralization, subsequently affecting the net C balance. Collectively, our results provided solid evidence that labile C input could lead to a positive net C balance, which diminished with increased historical N application and was primarily regulated by soil C:N:P stoichiometry. This study highlights the significant implications for the soil C turnover and sequestration under long-term N application management in agroecosystems.
期刊介绍:
Soil & Tillage Research examines the physical, chemical and biological changes in the soil caused by tillage and field traffic. Manuscripts will be considered on aspects of soil science, physics, technology, mechanization and applied engineering for a sustainable balance among productivity, environmental quality and profitability. The following are examples of suitable topics within the scope of the journal of Soil and Tillage Research:
The agricultural and biosystems engineering associated with tillage (including no-tillage, reduced-tillage and direct drilling), irrigation and drainage, crops and crop rotations, fertilization, rehabilitation of mine spoils and processes used to modify soils. Soil change effects on establishment and yield of crops, growth of plants and roots, structure and erosion of soil, cycling of carbon and nutrients, greenhouse gas emissions, leaching, runoff and other processes that affect environmental quality. Characterization or modeling of tillage and field traffic responses, soil, climate, or topographic effects, soil deformation processes, tillage tools, traction devices, energy requirements, economics, surface and subsurface water quality effects, tillage effects on weed, pest and disease control, and their interactions.