A great quantity of sediment deposited on the lower river course and riverbed gradually raised and suspended is the essential reason of severe threatening of floods in the lower Weihe river.

大量的泥沙淤积在下游河道，河床逐渐淤高，是渭河下游水患威胁严重的根本原因。

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First, erosion resulting from excessive deforestation in the upper reaches of the river. And second, heavy silting which raised the riverbed in the main channel.

第一，过度砍伐引起的河流上游的侵蚀，第二，严重的泥沙淤积抬高了主干道的河床。

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