Effects of mixed cereal/legume straw application on carbon sequestration in black loessial soils with contrasting soil organic carbon contents.

Soil organic carbon (SOC) content and its sequestration efficiency were determined at the end of the incubation. Major equipment used in the experiment included a total organic carbon analyzer (for DOC measurement), the chloroform fumigation-extraction method with associated analytical instruments (for MBC and MBN determination), a fluorescence microplate method (for enzyme activity assays), and an elemental analyzer (for SOC measurement).

During data processing, mean values and standard errors were calculated for all indicators to reflect the variability within each treatment group.The dataset comprises ten data tables (Excel worksheets). In each table, “Incubation day” serves as the row label, indicating the sampling time point (unit: day); the column labels include the names of the different treatment groups and their corresponding standard errors.

The number of records varies among tables depending on the indicator measured. For instance, the tables for CO₂ release rate and cumulative CO₂ release contain 18 time points (days 1, 2, 3, 4, 5, 7, 10, 13, 18, 23, 28, 35, 42, 49, 56, 67, 97, and 127), whereas DOC, MBC, MBN, and enzyme activities were typically measured at key time points only (days 0, 7, 27, 67, and 127), with 5 to 6 records. The SOC table uses different treatments as row labels and records initial SOC, new SOC, net SOC sequestration, and carbon sequestration efficiency.The units of measurement involved in each data table are as follows: CO₂ release rate is expressed in mg C·kg⁻¹·d⁻¹; both cumulative and stage CO₂ release are in mg C·kg⁻¹; DOC, MBC, and MBN are in mg·kg⁻¹; enzyme activities (BG, CBH, BXYL, etc.) are in nmol·h⁻¹·g⁻¹; SOC is in g·kg⁻¹; and carbon sequestration efficiency is a dimensionless percentage.

Each treatment group is accompanied by a standard error column to represent the variability among replicate samples. The entire dataset systematically documents the dynamic changes in soil carbon mineralization, microbial activity, and carbon sequestration capacity under different treatments, making it suitable for analyzing the effects of organic material and straw addition on soil carbon cycling processes.