Table 4 Random forest importance ranking of four habitat hydraulic variables and physicochemical factors on freshwater mussel density in Poyang Lake
Rank | Hydraulic predictors | % increase in MSE |
|---|---|---|
1 | Re* (unitless) | 8.5 |
2 | Ï„c (N/m2) | 6.5 |
3 | ks (mm) | 6.0 |
4 | D (mm) | 6.0 |
5 | Fr (unitless) | 5.9 |
6 | Ï„ (N/m2) | 3.5 |
7 | So (unitless) | 3.3 |
8 | V (m/s) | 2.9 |
9 | Re (unitless) | 2.7 |
Rank | Physicochemical factors | % increase in MSE |
|---|---|---|
1 | T (℃) | 8.2 |
2 | Chl-a (mg/L) | 5.4 |
3 | SD (cm) | 3.4 |
4 | pH (unitless) | 4.0 |
5 | TN (mg/L) | 1.6 |
6 | DO (%) | 1.6 |
7 | TP (mg/L) | 1.5 |
8 | WD (m) | − 0.2 |