ptfkit.oosterveld1980¶
import ptfkit.oosterveld1980;
Exported namespace: ptfkit::oosterveld1980
Oosterveld and Chang (1980), soil-moisture retention from texture and depth.
Source¶
Oosterveld, M., & Chang, C. (1980). Empirical relations between laboratory determinations of soil texture and moisture retention. Canadian Agricultural Engineering, 22, 149-151.
Scope¶
Territory: Southern Alberta, Canada
Dataset: 1,137 pressure-plate analyses on 298 soil samples from the Lethbridge Research Station laboratory; the field-capacity tension regression used 134 samples.
Functions¶
calc_ptf_oosterveld1980_field_capacity_tension¶
Estimate field-capacity tension from clay content.
[[nodiscard]]
inline double calc_ptf_oosterveld1980_field_capacity_tension(double clay)
Parameters¶
| Name | Description |
|---|---|
clay | Clay content in percent by weight; the field-capacity tension experiment covered 2% to 72% clay. (% mass) |
Returns¶
Predicted tension corresponding to cylinder-method field capacity. (kPa)
Note
Equation 1 reports r = 0.67 and n = 134.
calc_ptf_oosterveld1980_retention¶
Estimate gravimetric soil-moisture content from texture, depth, and tension.
[[nodiscard]]
inline double calc_ptf_oosterveld1980_retention(double clay, double sand, double mean_depth, double tension)
Parameters¶
| Name | Description |
|---|---|
clay | Clay content in percent by weight. (% mass) |
sand | Sand content in percent by weight. (% mass) |
mean_depth | Mean depth of the soil sample. (cm) |
tension | Soil-moisture tension. (kPa) |
Returns¶
Predicted soil-moisture content in percent by weight. (% mass)
Note
Equation 2 reports r = 0.96 and n = 1,137.
Warning
The paper reports slight inaccuracy at very high clay content and high tension.
calc_ptf_oosterveld1980_field_capacity¶
Estimate gravimetric soil-moisture content at field capacity.
[[nodiscard]]
inline double calc_ptf_oosterveld1980_field_capacity(double clay, double sand, double mean_depth)
Parameters¶
| Name | Description |
|---|---|
clay | Clay content in percent by weight; the field-capacity tension experiment covered 2% to 72% clay. (% mass) |
sand | Sand content in percent by weight. (% mass) |
mean_depth | Mean depth of the soil sample. (cm) |
Returns¶
Predicted soil-moisture content at field capacity in percent by weight. (% mass)
Note
Equation 3 is obtained by substituting the Equation 1 field-capacity tension into Equation 2.
calc_ptf_oosterveld1980_wilting_point¶
Estimate gravimetric soil-moisture content at the 1500 kPa wilting point.
[[nodiscard]]
inline double calc_ptf_oosterveld1980_wilting_point(double clay, double sand, double mean_depth)
Parameters¶
| Name | Description |
|---|---|
clay | Clay content in percent by weight. (% mass) |
sand | Sand content in percent by weight. (% mass) |
mean_depth | Mean depth of the soil sample. (cm) |
Returns¶
Predicted soil-moisture content at 1500 kPa in percent by weight. (% mass)
Note
Equation 4 reports r = 0.96 and n = 298.
Note
The paper takes moisture content at 1500 kPa as the wilting point.
calc_ptf_oosterveld1980_available_water¶
Estimate available gravimetric soil moisture between field capacity and wilting point.
[[nodiscard]]
inline double calc_ptf_oosterveld1980_available_water(double clay, double sand, double mean_depth)
Parameters¶
| Name | Description |
|---|---|
clay | Clay content in percent by weight; the field-capacity tension experiment covered 2% to 72% clay. (% mass) |
sand | Sand content in percent by weight. (% mass) |
mean_depth | Mean depth of the soil sample. (cm) |
Returns¶
Predicted field-capacity moisture minus predicted wilting-point moisture, in percentage points by weight. (% mass)
Note
The paper defines available soil water by subtracting Equation 4 from Equation 3.