Lithologic Control on the Scaling Properties of the First‐Order Streams of Drainage Networks: A Monofractal Analysis

Abstract

The interrelation between bedrock lithology and the geometry of the drainage systems has been widely studied in the last decades. The quantification of this linkage has not yet been clearly established. Several studies have selected river basins or regularly shaped areas as study units, assuming them to be lithologically homogeneous. This study considered irregular distributions of rock types, establishing areas of the soil map (1:25,000) with the same lithologic information as study units. The tectonic stability and the low climatic variability of the study region allowed effective investigation of the lithologic controls on the drainage networks developed on the plutonic rocks, the metamorphic rocks, and the sedimentary materials existing in the study area. To exclude the effect of multiple in‐ and outflows in the lithologically homogeneous units, we focused this study on the first‐order streams of the drainage networks. The geometry of the hydrologic features was quantified through traditional metrics of fluvial geomorphology and scaling parameters of fractal analysis, such as the fractal dimension, the reference density, and the lacunarity. The results demonstrate the scale invariance of both the drainage networks and the set of first‐order streams at the study scale and a relationship between scaling in the lithology and the drainage network.

Quantifying patterns of complexity controlled by parent material at different spatial scales: from drainage network architecture at landscape scale to soil texture. A hydropedologic research conducted on wine regions of the Douro river basin

“…The D of the drainage system of the metamorphic units (1.1526 ± 0.0473) is lower than D of the plutonic rock units (1.1784 ± 0.0338). This behavior was already observed in other locations of the same region in the work of Cámara et al (2013). The lacunarity of the drainage system developed on metamorphic rocks (1.0036 ± 0.0009) is lower than Λ of the plutonic rock units (1.0049 ± 0.0008).…”

“…It is noteworthy that the thesis' author has worked exhaustively in the generation of most of the databases used in this research. He dedicated several months in the identification and digitization of the drainage network used by Cámara et al (2013Cámara et al ( , 2016a, and he participated during three years as soil surveyor in the team that carried out all the field work involved in the creation of the soil maps 1/25,000 (Gómez-Miguel et al, 2011a,b) has represented the major effort in this hydropedologic research.…”

“…Chapter 1 is entitled "Lithologic control on the scaling properties of the firstorder streams of drainage networks: a monofractal analysis", and it was published in 2013 in Vadose Zone Journal 12 (Cámara et al, 2013). Chapter 1 explores the influence of parent material in the hierarchical structure of the drainage networks at landscape scale.…”

“…Recently, the relationship between lithology and the hierarchical architecture of drainage networks has been shown, and quantified by means of fractal dimension (Cámara et al, 2013). On the other hand, fragmentation (Perfect, 1997) and the erosion processes of different types of rocks are expected to generate different soil textures.…”

“…However, the study units in these works were entire basins (Dombradi et al, 2007) or large areas of 100s of km 2 (Gaudio et al, 2006), where more than one homogeneous bedrock lithology would be expected. The use of study units defined by semi-detailed scale lithological maps has been recently suggested (Bloomfield et al, 2011;Cámara et al, 2013) and could enlighten the problem and provide further conclusive results.…”