> For the complete documentation index, see [llms.txt](https://swatplus.gitbook.io/io-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://swatplus.gitbook.io/io-docs/introduction-1/soils/nutrients.sol.md).

# nutrients.sol

This file specifies the initial soil nutrient contents.

| Field                                                                     | Description                                                   | Type   | Unit | Default | Range |
| ------------------------------------------------------------------------- | ------------------------------------------------------------- | ------ | ---- | ------- | ----- |
| [name](/io-docs/introduction-1/soils/nutrients.sol/name-nutrients.sol.md) | Name of the soil nutrient record                              | string |      |         |       |
| [exp\_co](/io-docs/introduction-1/soils/nutrients.sol/exp_co.md)          | Depth coefficient to adjust nutrient concentrations for depth |        |      |         |       |
| [lab\_p](/io-docs/introduction-1/soils/nutrients.sol/lab_p.md)            | Labile P in soil surface                                      |        |      |         |       |
| [nitrate](/io-docs/introduction-1/soils/nutrients.sol/nitrate.md)         | Nitrate N in soil surface                                     |        |      |         |       |
| [fr\_hum\_act](/io-docs/introduction-1/soils/nutrients.sol/fr_hum_act.md) | Fraction of soil humus that is active                         |        |      |         |       |
| [hum\_c\_n](/io-docs/introduction-1/soils/nutrients.sol/hum_c_n.md)       | Humus C:N ratio                                               |        |      |         |       |
| [hum\_c\_p](/io-docs/introduction-1/soils/nutrients.sol/hum_c_p.md)       | Humus C:P ratio                                               |        |      |         |       |
| inorgp                                                                    | Currently not used                                            |        |      |         |       |
| watersol\_p                                                               | Currently not used                                            |        |      |         |       |
| h3a\_p                                                                    | Currently not used                                            |        |      |         |       |
| mehlich\_p                                                                | Currently not used                                            |        |      |         |       |
| bray\_strong\_p                                                           | Currently not used                                            |        |      |         |       |