To explore the impact of soil moisture variation on the relationship between soil organic carbon (SOC) and color characteristic parameters, and to construct quantitative SOC prediction models based on color parameters, soil sample images under different soil moisture content (SMC) conditions were acquired by simulating continuous changes of farmland soil moisture to extract color characteristic parameters. Various mathematical transformation methods were employed to optimize these parameters. Combined with correlation analysis and regression models, the influence of soil moisture on the relationship between color characteristics and SOC was quantified, and SOC quantitative estimation models under different moisture conditions were established. The results indicated that SOC was significantly and negatively correlated with color characteristic parameters in RGB, HSV, and CIELab color spaces, with R, L, and V components showing the highest correlation. Reciprocal and logarithmic transformations enhanced these correlations. Soil moisture affected color component values; as SMC increased, most color parameter values decreased, and their correlation with SOC gradually weakened. Critical moisture contents were identified as SMC=15%. Color parameters such as 1/b*, lnb*, 1/S, and lnS effectively mitigated the impact of moisture on SOC prediction models. Under different moisture conditions, the BP neural network regression model outperformed the linear regression model, demonstrating superior predictive capability. This study demonstrates that the color characteristic parameters of digital images can be effectively utilized for the quantitative analysis of SOC.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |