Table 1.
Covariates of total nitrogen (TN) included in the study and their correlation with log (TN) within all streams
| Variable | Description | Units | r |
|---|---|---|---|
| ELEV | Elevation | m | − 0.18 |
| Longitude | Longitude | Degree | 0.57 |
| Log(PRECIP) | Annual precipitation in log scale | mm | − 0.58 |
| Log(AREA) | Catchment area in log scale | km2 | 0.47 |
| Log(CL) | Cl− concentration in log scale | μg/L | 0.62 |
| Log(HCO3) | HCO3− concentration in log scale | μg/L | 0.55 |
| Log(SO4) | SO4−2 concentration in log scale | μg/L | 0.61 |
| SED | Sand and fine substrate in the stream (< 2 mm in diameter) | μg/L | 0.63 |
| STRMTEMP | Stream temperature | Degree | 0.49 |
| Percent.AGT | Percentage of catchment in agricultural land use | μg/L | 0.57 |
| Percent.URB | Percentage of catchment in urban land | Percentage | 0.30 |
| Percent.Canopy | Percentage of open canopy | Percentage | 0.47 |
| Riparian.Disturb | Riparian agricultural disturbance index | Index | 0.49 |
All correlation coefficients are statistically significant (p < 0.05)