Environmental variables	Mean	Minimum	Maximum	Coefficient of variation (%)
Width (m)	3.60	1.15	5.9	139.28
Length (m)	6.05	3.00	11.5	299.75
Area (m2)	21.08	4.83	53.34	57.43
Depth (cm)	12.11	5.50	16.03	26.63
Flow (m/sec)	1.47	0.97	2.19	391.07
Shading (%)	62.65	17.22	100.00	152.82
Sand (%)	0.15	0.00	2.50	287.68
Rock (%)	12.35	0.00	60.00	94.04
Gravel (%)	0.01	0.00	0.14	87.04
Pebble (%)	27.76	0.01	72.50	282.29
Boulder (%)	26.16	0.23	78.33	20.23
Root (%)	0.01	0.00	0.08	39.88