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Map of the South Llano River study area in Kimble County, Texas with stream reaches as demarcated by road crossings or natural barriers indicated. Inset maps illustrate the location of the South Llano River within the Colorado River Basin and the continental US.

Map of the South Llano River study area in Kimble County, Texas with stream reaches as demarcated by road crossings or natural barriers indicated. Inset maps illustrate the location of the South Llano River within the Colorado River Basin and the continental US.

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Habitat heterogeneity at multiple scales is a major factor affecting fish assemblage structure. However, assessments that examine these relationships at multiple scales concurrently are lacking. The lack of assessments at these scales is a critical gap in understanding as conservation and restoration efforts typically work at these levels.A combina...

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... with most catchments on the Edwards Plateau the South Llano River has relatively low levels of human impact largely because of low population densities within the catchment and comparatively little water withdrawn for agricultural or municipal purposes ( Linam et al., 2002). The study area consisted of a 39 km reach beginning approximately 1.5 km upstream of the confluence of the South Llano River and Paint Creek and ended at Lake Junction Dam in Junction (Figure 1). Owing to drought conditions, a decreasing trend in mean daily discharge was observed throughout 2012-2013, with an overall mean (± SD) discharge of only 1.4 ± 0.3 m 3 s À1 compared with a historical median of 2.0 m 3 s À1 (mean ± SD = 3.6 ± 25.7 m 3 s À1 ). ...
Context 2
... reach scale was defined as sections of river uninterrupted by any type of artificial or natural barriers, e.g. road crossings or a waterfall (Figure 1). Seven non-overlapping reaches were identified within the study area (mean area ± SD: 170 123 ± 119 542 m 2 ; range: 52 512-337 016 m 2 ). ...

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