Premium
On the cumulative area distribution of natural drainage basins along a coastal boundary
Author(s) -
La Barbera P.,
Lanza L. G.
Publication year - 2001
Publication title -
water resources research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.863
H-Index - 217
eISSN - 1944-7973
pISSN - 0043-1397
DOI - 10.1029/2000wr900382
Subject(s) - structural basin , drainage basin , hydrology (agriculture) , geology , drainage , boundary (topology) , geomorphology , geography , mathematics , geotechnical engineering , cartography , ecology , mathematical analysis , biology
The natural drainage network in a region is analyzed in order to investigate scaling properties and the form of the probability distribution for basin areas along a coastal boundary. The Horton/Strahler approach used in the classical description of the drainage network within a single basin is extended to a series of independent though conterminous basins with outlet to the sea, assuming that a regional area ratio R A , analogous to the Hortonian area ratio, holds for independent basins. A multiplicative factor R c is also defined as the average ratio between the number of independent basins of a given order ω and those of order ω+1. The cumulative area distribution (CAD) for drainage basins that drain along the coastal boundary is obtained as a power law in the form P[ A > a ] ∝ a −γ , with γ = log R c /log R A . The derived form and parameters of the CAD are shown to hold for the Liguria region of Italy (≃5700 km 2 in the northern Mediterranean) as well as for the whole continental Italy (≃250,000 km 2 ). The fractal dimension of the regional system encompassing all drainage areas of basins with outlet to the sea is derived in the form = 1/γ. The analytical results obtained are shown to agree with the theoretical expressions already available in the literature for optimal channel networks.