Table 1 General characteristics of the three study segments and two seasons.

From: Effects of sediment replenishment on riverbed environments and macroinvertebrate assemblages downstream of a dam

Variables

Seasons

Study segments and reaches

UD

DD

TR

1

2

1

2

1

2

Distance from the dam (km)

 

5.3

4.1

1.1

2.4

4.3 (1.6)

3.3 (0.6)

Elevation (m a.s.l.)

 

469

432

304

286

324

289

Catchment area (km2)

 

21.5

35.4

83.4

84.7

20.7

21.2

Slope (%)*

 

3.5

2.6

1.1

1.4

2.6

2.5

Discharge (m3 s-1)**

March

1.6 ± 0.3

1.4 ± 0.8

1.1 ± 0.4

1.5 ± 0.4

0.4 ± 0.1

0.5 ± 0.1

August

2.2 ± 0.4

3.8 ± 0.8

3.6 ± 0.4

4.1 ± 0.4

0.7 ± 0.1

0.9 ± 0.2

Wetted width (m)**

March

10.3 ± 2.1

10.2 ± 1.8

8.4 ± 1.9

8.9 ± 1.6

4.5 ± 0.6

5.6 ± 1.2

August

14.0 ± 0.8

12.5 ± 0.4

11.2 ± 1.0

10.9 ± 1.6

5.7 ± 1.0

6.4 ± 1.6

  1. The distance of the tributary (TR) from the dam is the sum of distances from the dam to the tributary confluence, and from the confluence to the TR. Values in parentheses show the distance from the confluence. Data are shown as mean ± 1 SD (n = 6) where applicable.
  2. UD upstream of dam, DD downstream of dam.
  3. *Calculated from geographycal information system elevation data (50–3 resolutions; Geographical Survey Institute of Japan).
  4. **Based on 6 transect lines across the channel at each study reach; flow discharge estimated from velocity at 60% of the depth and water depth at 5 equidistant points along each transect.
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