### 2.11.1.1. Vertical Root Distribution[¶](#vertical-root-distribution "Permalink to this headline")

The root fraction \\(r\_{i}\\) in each soil layer depends on the plant functional type

(2.11.1)[¶](#equation-11-1 "Permalink to this equation")\\\[r\_{i} = \\begin{array}{lr} \\left(\\beta^{z\_{h,\\, i-1} \\cdot 100} - \\beta^{z\_{h,\\, i} \\cdot 100} \\right) & \\qquad {\\rm for\\; }1 \\le i \\le N\_{levsoi} \\end{array}\\\]

where \\(z\_{h,\\, i}\\) (m) is the depth from the soil surface to the interface between layers \\(i\\) and \\(i+1\\) (\\(z\_{h,\\, 0}\\), the soil surface) (section [2.2.2](https://escomp.github.io/ctsm-docs/versions/master/html/tech_note/Ecosystem/CLM50_Tech_Note_Ecosystem.html#vertical-discretization)), the factor of 100 converts from m to cm, and \\(\\beta\\) is a plant-dependent root distribution parameter adopted from [Jackson et al. (1996)](https://escomp.github.io/ctsm-docs/versions/master/html/tech_note/References/CLM50_Tech_Note_References.html#jacksonetal1996) ([Table 2.11.1](#table-plant-functional-type-root-distribution-parameters)).

Table 2.11.1 Plant functional type root distribution parameters[¶](#id12 "Permalink to this table")  
| Plant Functional Type
 | \\(\\beta\\)

 |
| --- | --- |
| NET Temperate

 | 0.976

 |
| NET Boreal

 | 0.943

 |
| NDT Boreal

 | 0.943

 |
| BET Tropical

 | 0.993

 |
| BET temperate

 | 0.966

 |
| BDT tropical

 | 0.993

 |
| BDT temperate

 | 0.966

 |
| BDT boreal

 | 0.943

 |
| BES temperate

 | 0.964

 |
| BDS temperate

 | 0.964

 |
| BDS boreal

 | 0.914

 |
| C3 grass arctic

 | 0.914

 |
| C3 grass

 | 0.943

 |
| C4 grass

 | 0.943

 |
| Crop R

 | 0.943

 |
| Crop I

 | 0.943

 |
| Corn R

 | 0.943

 |
| Corn I

 | 0.943

 |
| Temp Cereal R

 | 0.943

 |
| Temp Cereal I

 | 0.943

 |
| Winter Cereal R

 | 0.943

 |
| Winter Cereal I

 | 0.943

 |
| Soybean R

 | 0.943

 |
| Soybean I

 | 0.943

 |
| Miscanthus R

 | 0.943

 |
| Miscanthus I

 | 0.943

 |
| Switchgrass R

 | 0.943

 |
| Switchgrass I

 | 0.943

 |

