hydrus的T_Level一共有21个变量，其具体的解释说明在help中已进行了解释和说明。这里把它们
一一对应起来方便查找。
| help含义 | 序号 | 变量名 | manul | 单位 | ||
| Time | Time | [T] | ||||
| Potential upper boundary flux (precipitation, irrigation, or potential evaporation) | 1 | rTop | Potential Surface Flux | [L/T] | ||
| Potential root water uptake rate | 2 | rRoot | Potential Root Water Uptake | [L/T] | ||
| Actual upper boundary flux (infiltration or actual evaporation rate) | 3 | vTop | Actual Surface Flux | [L/T] | 关心 | 实际表面通量 |
| Actual root water uptake rate | 4 | vRoot | Actual Root Water Uptake | [L/T] | 关心 | 实际根系水速率 |
| Lower boundary flux | 5 | vBot | Bottom Flux | [L/T] | 关心 | 底部通量 |
| Cumulative potential upper boundary flux | 6 | sum_rTop | Cum. Potential Surface Flux | [L] | ||
| Cumulative potential root water uptake rate | 7 | sum_rRoot | Cum. Potential Root Water Uptake | [L] | ||
| Cumulative actual upper boundary flux | 8 | sum_vTop | Cum. Actual Surface Flux | [L] | 关心 | 累积实际表面通量 |
| Cumulative actual root water uptake rate | 9 | sum_vRoot | Cum. Actual Root Water Uptake | [L] | 关心 | 累积实际根吸水量 |
| Cumulative lower boundary flux | 10 | sum_vBot | Cum. Bottom Flux | [L] | 关心 | 累积底部通量 |
| Soil surface pressure head | 11 | hTop | Surface Pressure Head | [L] | ||
| Average root zone pressure head | 12 | hRoot | Root Zone Pressure Head | [L] | ||
| Lower boundary pressure head | 13 | hBot | Bottom Pressure Head | [L] | ||
| All fluxes | All Fluxes | |||||
| All cumulative fluxes | All Cumulative Fluxes | |||||
| All pressure heads | All Pressure Head | |||||
| Surface runoff | 14 | RunOff | Surface Run-Off | [L/T] | ||
| 15 | sum_RunOff | Cum. Surface Run-Off | [L] | |||
| Soil water storage | 16 | Volume | Soil Water Storage | [L] | 关心 | 土壤蓄水量 |
| Cumulative infiltration | 17 | sum_Infil | Cum. Infiltration | [L] | 关心 | 累积入渗量 |
| Cumulative evaporation | 18 | sum_Evap | Cum. Evaporation | [L] | 关心 | 累积蒸发量 |
| 19 | Tlevel | |||||
| Cumulative non-equilibrium water transfer (in dual-porosity models) | 20 | Cum_Wtrans | Cum. Non-Equil. Water Transfer | |||
| Snow Layer | 21 | SnowLayer | Snow Layer |
其中这些变量之间还有一些内部平衡的关系：
| 累积表面通量=累积蒸发量-累积入渗量 |
| 累积底部通量=累积蒸发量+累积实际根吸水量-累积入渗量-储水量减少量 |
| 累积底部通量=ET-累积入渗量-储水量减少量 |
| 累积底部通量=累积表面通量+累积实际根吸水量-储水量减少量 |