Data from: The impact of black soil degradation on saturated hydraulic conductivity
Data files
May 05, 2026 version files 19.26 KB
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LSD_results.csv
4.56 KB
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mantel_test_results_mantel_r_p.csv
624 B
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manteltest_results_correlation_coefficients.csv
6.37 KB
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Raw_date_average_value.csv
4.07 KB
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README.md
3.63 KB
Abstract
Severe soil degradation represents a critical threat to agricultural productivity and ecological sustainability in the black soil region of Northeast China. Prolonged anthropogenic cultivation has induced varying degrees of degradation, markedly impairing soil hydraulic properties—particularly saturated hydraulic conductivity (Ksat). As Ksat is governed by multiple interrelated pedological processes, its temporal dynamics under long-term cultivation remain poorly understood, especially with respect to the relative influence of key controlling factors across degradation stages. This study investigates how cultivation history and progressive soil degradation jointly regulate Ksat in black soils of Northeast China. Results indicate that soil organic matter (SOM) declines exponentially with cultivation duration, approaching a carbon equilibrium state after approximately 150 years of continuous farming. Across degradation gradients, Ksat exhibits a non-linear, unimodal response to both the soil structural stability index (SSI) and SOM—initially increasing and subsequently declining. Crucially, the dominant control on Ksat shifts from nutrient-related properties (e.g., SOM content) during early degradation to structural and textural attributes (e.g., aggregate stability, clay dispersion, pore continuity) under severe degradation. Separate regression models were developed for mildly and severely degraded soils to quantify these divergent controls. Collectively, these findings elucidate the dynamic hydrological mechanisms underlying soil degradation and offer a robust scientific foundation for improving hydrological modeling, land-use planning, and targeted soil conservation strategies in the black soil region.
Dataset DOI: 10.5061/dryad.xpnvx0kwk
Description of the data and file structure
This dataset was collected from 40 farmland plots with varying reclamation histories and degradation levels in the Acheng District of Harbin, located in the black soil region of Northeast China. Undisturbed and disturbed soil samples were collected from the 0–20 cm plow layer. Soil physicochemical properties (including organic matter, nitrogen, phosphorus, potassium, pH, particle size distribution, bulk density, and porosity) and hydraulic parameters (saturated water content and saturated hydraulic conductivity, Ksat) were measured following standard soil science protocols. Degradation levels were classified using the Soil Structural Stability Index (SSI). These data aim to elucidate the variation characteristics and driving mechanisms of Ksat along the black soil degradation gradient, and can support research in soil hydrology, degradation assessment, and soil and water conservation.
Files and variables
File: Raw_date_average_value.csv
Description: Mean values of soil physicochemical properties across 40 sampling plots
Variables
- Plot_ID:Sample plot identifier
- Degradation_Level:Soil degradation level (SD = severe degradation; MD = mild degradation; RD = risk degradation)
- Ksat:Saturated hydraulic conductivity (mm min⁻¹)
- SOM:Soil organic matter (g kg⁻¹)
- Pt:Total porosity (%)
- Pc:Capillary porosity (%)
- Pn:Non-capillary porosity (%)
- BD:Bulk density (g cm⁻³)
- SWC:Soil saturated water content (%)
- pH:Soil pH (1:2.5 soil-water suspension)
- Clay:Clay content (%)
- Silt:Silt content (%)
- Sand:Sand content (%)
- TN:Total nitrogen (g kg⁻¹)
- AP:Available phosphorus (mg kg⁻¹)
- AK: Available potassium (mg kg⁻¹)
- SSI:Soil structural stability index (%)
- EL:Elevation(m)
File: LSD_results.csv
Description: Analysis of significant differences and least significant difference(LSD) in various degrees of degradation
Variables
- Indicator:Soil physical and chemical properties
- test:
- Level(I):Degree of degeneration
- Level(J):Degree of degeneration
- Average difference (I-J):When the P-value from the LSD test for two datasets(MD vs RD or MD vs SD or RD vs SD) is less than 0.05, an asterisk (*) shall be appended to the mean difference. This denotes that the difference between the two datasets is statistically significant, rather than arising from random error. vs=versus.
- Standard error:
- Pvalue:
- 95% Confidence interval:
File: manteltest_results_correlation_coefficients.csv
Description: Correlation of soil physical and chemical properties by Mantel test
Variables
- :
- Indicator1:Soil physical and chemical properties
- Indicator2:Soil physical and chemical properties
- r:correlation coefficient
- p:P-value
File: mantel_test_results_mantel_r_p.csv
Description: The overall correlation strength between reclamation ages and soil physicochemical properties
Variables
- :Serial Number
- Y1:reclamation ages
- Indicator:soil physicochemical properties
- r:Mantel correlation coefficient
- p:Mantel P-value
Access information
Other publicly accessible locations of the data:
- Not applicable. This is the first public deposition of the dataset.
Data was derived from the following sources:
- Data was derived from field sampling and laboratory measurements in black soil farmland of Acheng District, Harbin, Heilongjiang Province, China.
