{"title":"Successive utilization of carbon from different biogenic sources leads to continuous enhancement of soil respiration","authors":"","doi":"10.1016/j.still.2024.106327","DOIUrl":null,"url":null,"abstract":"<div><div>Climate change affects soil organic carbon (SOC) by altering plant carbon inputs and microbial metabolic processes. On the Tibetan Plateau, which is rich in SOC and sensitive to climate change, investigations on the absolute SOC content affecting soil respiration (Rs) were extensive. However, the relationship between Rs and the SOC composition remains largely unclear. Employing a combination of data collection, large-scale field surveys, and analysis, with lignin phenols and amino sugars indicating plant and microbial SOC components, we observed an increase in Rs (3.747 kg C ha<sup>−1</sup> yr<sup>−1</sup>) correlating with rising SOC stocks (0–30 cm; 8.6 kg C ha<sup>−1</sup> yr<sup>−1</sup>). Our results showed that Rs is predominantly driven by plant-derived carbon, especially cinnamyl phenol carbon, which is significantly influenced by vegetation characteristics and soil properties. Although microbial-derived carbon has a minimal overall impact on Rs, fungal necromass carbon critically regulates Rs, underscoring the complex interactions between microbial- and plant-derived components under diverse environmental conditions. The rapid, short-term accumulation of plant-derived carbon significantly enhanced Rs and led to substantial microbial carbon accumulation. As the levels of microbial-derived carbon increase, the Rs process tends to utilize this carbon, potentially altering and reducing the SOC composition and stability, respectively, thereby leading to a continuous increase in soil respiration. These findings offer new insights into Rs and SOC dynamics within the grassland ecosystem of the Tibetan Plateau and provide a scientific basis for predicting the response of soil carbon to climate change.</div></div>","PeriodicalId":49503,"journal":{"name":"Soil & Tillage Research","volume":null,"pages":null},"PeriodicalIF":6.1000,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Soil & Tillage Research","FirstCategoryId":"97","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0167198724003283","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
Climate change affects soil organic carbon (SOC) by altering plant carbon inputs and microbial metabolic processes. On the Tibetan Plateau, which is rich in SOC and sensitive to climate change, investigations on the absolute SOC content affecting soil respiration (Rs) were extensive. However, the relationship between Rs and the SOC composition remains largely unclear. Employing a combination of data collection, large-scale field surveys, and analysis, with lignin phenols and amino sugars indicating plant and microbial SOC components, we observed an increase in Rs (3.747 kg C ha−1 yr−1) correlating with rising SOC stocks (0–30 cm; 8.6 kg C ha−1 yr−1). Our results showed that Rs is predominantly driven by plant-derived carbon, especially cinnamyl phenol carbon, which is significantly influenced by vegetation characteristics and soil properties. Although microbial-derived carbon has a minimal overall impact on Rs, fungal necromass carbon critically regulates Rs, underscoring the complex interactions between microbial- and plant-derived components under diverse environmental conditions. The rapid, short-term accumulation of plant-derived carbon significantly enhanced Rs and led to substantial microbial carbon accumulation. As the levels of microbial-derived carbon increase, the Rs process tends to utilize this carbon, potentially altering and reducing the SOC composition and stability, respectively, thereby leading to a continuous increase in soil respiration. These findings offer new insights into Rs and SOC dynamics within the grassland ecosystem of the Tibetan Plateau and provide a scientific basis for predicting the response of soil carbon to climate change.
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.