Distinct mechanisms of organic carbon accumulation in cropland and bare land under different nitrogen gradients revealed by a 16-year field experiment
Description
1. Research Hypotheses: This study was designed to test the central hypothesis that the mechanisms governing soil organic carbon (SOC) accumulation differ under long-term nitrogen gradient fertilization between cropland and bare land in the Fluvo-Aquic soil region of the North China Plain. 2. Data Description: This dataset comprises crop yield data collected annually from 2009 to 2025 across 21 experimental plots, alongside soil sample analysis data obtained in 2025 from 42 experimental plots. Key measured indicators include: Soil Carbon Fractions: Soil Organic Carbon (SOC), Dissolved Organic Carbon (DOC), particulate organic carbon (POC), mineral-associated organic carbon (MAOC), nonprotected organic carbon (Non-C), physically protected organic carbon (Phy-C), chemically protected organic carbon (Che-C), biochemically protected organic carbon (Bio-C). Other Soil Properties: Total Nitrogen (TN) and pH. 3. Notable Findings: Our analysis revealed distinct regulatory pathways for SOC accumulation. In cropland systems, Bio-C exerted a dominant influence on POC, which subsequently governed SOC sequestration. Conversely, in bare land systems, the limited presence of Che-C attenuated the role of POC, resulting in MAOC serving as the principal regulator of SOC dynamics. 4. Data Interpretation and Reuse Potential: The data are presented in a structured Excel format, readily accessible for statistical analysis. Users can leverage this dataset to compare the effects of nitrogen application rates and land use types on soil carbon pools and physicochemical properties. It is suitable for calibrating biogeochemical models, refining regional SOC stock estimates, and evaluating the efficacy of land management strategies aimed at enhancing soil carbon sequestration.
Files
Steps to reproduce
Use SPSS for data analysis and Origin for graphing.