Table 2.

Mean, minimum, maximum, and standard deviation (SD) of local environmental variables, species richness, and abundance at local riffle sites in the three drainage basins and in all basins combined. Also, the watercourse and overland distances between sites are shown

	Iijoki basin (n = 20)			Koutajoki basin (n = 20)			Tenojoki basin (n = 30)			All basins (n = 70)
	Mean	Min–max	SD	Mean	Min–max	SD	Mean	Min–max	SD	Mean	Min–max	SD
Conductivity (mS/m)	2.1	1.5–3.1	0.4	7.0	2.8–17.5	3.7	1.8	1.2–2.4	0.3	3.4	1.2–17.5	3.0
pH	6.4	5.7–6.9	0.3	7.3	6.8–7.9	0.3	6.6	6.3–6.7	0.1	6.7	5.7–7.9	0.5
Shading (%)	34	10–70	20	44	5–85	26	16	0–55	14	29	0–85	23
Deciduous (%)	35	5–80	19	44	10–75	15	100	98–100	0	65	5–100	33
Stream width (cm)	304	100–650	131	299	78–1200	266	575	88–2400	506	418	78–2400	388
Depth (cm)	24	16–35	7	25	10–46	10	19	13–33	5	22	10–46	8
Velocity (m/s)	0.4	0.2–0.7	0.2	0.5	0.2–1	0.2	0.4	0.1–0.6	0.1	0.4	0.1–1	0.2
Macrophytes (%)	44	1–78	23	11	0–43	15	4	0–16	4	18	0–78	23
Sand (%)	10	0–49	12	11	0–73	18	1	0–22	5	7	0–73	13
Gravel (%)	6	0–37	9	9	0–30	8	2	0–25	5	5	0–37	8
Pebble (%)	10	0–55	14	33	0–64	19	15	1–65	12	19	0–65	17
Cobble (%)	29	2–53	14	26	0–61	16	45	10–81	20	35	0–81	19
Boulder (%)	44	0–82	25	20	0–92	24	37	1–83	22	34	0–92	25
Local richness
PaAq	4	0–7	2	3	0–8	2	1	0–3	1	2	0–8	2
PaTe	14	6–25	4	15	7–27	6	10	2–20	4	12	2–27	5
AqTe	18	10–26	5	19	5–31	7	10	2–19	5	15	2–31	7
All taxa	36	22–49	9	36	18–53	10	21	7–40	8	30	7–53	11
Local abundance
PaAq	22	0–98	25	20	0–115	33	3	0–21	4	13	0–115	24
PaTe	335	36–1045	283	223	10–893	274	60	4–175	47	185	4–1045	240
AqTe	423	70–1685	371	219	47–571	155	247	17–1073	221	289	17–1685	269
All taxa	780	199–1875	473	462	171–1504	383	310	61–1269	253	488	61–1875	410
Watercourse distances (km)	105	0.78–213	59	30	1.54–86	67	57	0.94–165	65	–	–	–
Overland distances (km)	27	0.52–59	52	8.53	0.49–20	46	37	0.10–100	63	250	0.10–541	80