tributary

hydrology

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July 23, 2026

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A tributary is a stream that flows into a larger body of water, such as a river or lake. These smaller streams contribute to the overall flow and drainage basin of the larger watercourse. For example, the Amazon River has over 1,000 known tributaries, forming the world's largest drainage basin. Tributaries are essentially branches that feed into a main stream, contrasting with distributaries, which are channels that diverge from a main stream.123

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London
The valley of the Thames
…place, one must add the tributary streams running north and south from the hills to the great river on the valley floor, many of them rising from springs in the gravel. Those in the center of town have long since been culverted over, except where they do duty as ornamental…
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…place, one must add the tributary streams running north and south from the hills to the great river on the valley floor, many of them rising from springs in the gravel. Those in the center of town have long since been culverted over, except where they do duty as ornamental…
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river
Horton’s laws of drainage composition
…entry of first- and second-order tributaries, a third-order stream will not pass into the fourth order until it is joined by another third-order confluent. Stream number is the total number of streams of a given order for a given drainage basin. The bifurcation ratio is the ratio of the number…
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…entry of first- and second-order tributaries, a third-order stream will not pass into the fourth order until it is joined by another third-order confluent. Stream number is the total number of streams of a given order for a given drainage basin. The bifurcation ratio is the ratio of the number…
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