Table 2 Standardized total, direct and indirect effects of the driving factors of SWC (soil water content) in the Loess Tableland study area determined using structural equation models.
Soil depth/m | Standardized effect | Soil depth | Recovery years | Soil particle | SOC | BD | SWC | ||
|---|---|---|---|---|---|---|---|---|---|
Clay | Sand | ||||||||
SWC | 0–5 | Total | 0.643 | 0.138 | 0.239 | −0.001 | 0.481 | 0.049 | – |
Direct | 1.057 | 0.130 | 0.058 | 0.000 | 0.470 | 0.049 | – | ||
Indirect | −0.414 | 0.08 | 0.181 | −0.001 | 0.011 | 0.000 | – | ||
5–10 | Total | −0.542 | 0.571 | 0.300 | −0.014 | 0.093 | 0.084 | – | |
Direct | −0.423 | 0.428 | 0.293 | 0.000 | 0.062 | 0.084 | – | ||
Indirect | −0.119 | 0.143 | 0.006 | −0.014 | 0.032 | 0.000 | – | ||
10–15 | Total | −0.248 | 0.383 | 0.309 | 0.137 | 0.403 | −0.134 | – | |
Direct | −0.064 | 0.356 | −0.040 | 0.000 | 0.414 | −0.134 | – | ||
Indirect | −0.184 | 0.028 | 0.348 | 0.137 | −0.011 | 0.000 | – | ||
NO3−-N | 0–5 | Total | 0.642 | −0.362 | 0.338 | 0.121 | 0.222 | −0.085 | 0.077 |
Direct | 0.711 | −0.413 | 0.269 | 0.119 | 0.204 | −0.089 | 0.077 | ||
Indirect | −0.070 | 0.053 | 0.070 | 0.001 | 0.018 | 0.004 | 0.000 | ||
5–10 | Total | −0.600 | 0.338 | −0.181 | −0.043 | 0.126 | 0.258 | 0.471 | |
Direct | −0.646 | 0.208 | −0.299 | 0.000 | 0.000 | 0.219 | 0.471 | ||
Indirect | 0.047 | 0.130 | 0.118 | −0.043 | 0.126 | 0.039 | 0.000 | ||
10–15 | Total | 0.141 | −0.020 | 0.008 | −0.068 | −0.370 | 0.066 | −0.039 | |
Direct | −0.066 | 0.015 | 0.262 | 0.000 | −0.360 | 0.061 | −0.039 | ||
Indirect | 0.207 | −0.035 | −0.254 | −0.068 | −0.011 | 0.005 | 0.000 | ||
