There were grades in the population intension level from the lower reaches of the river to the upper river.

整个流域的人口分布沿黄河河道由下游往上，人口密集程度呈梯度递减的特征。

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Tonight, let's enjoy together the harp solo by the young performer Li Yange: Clear and Bright Upper River Picture.

今晚，让我们一起欣赏青年演奏家李彦歌的箜篌独奏：《清明上河图》。

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The Northern Border Project also includes five similar systems Boeing delivered to the Buffalo (N.Y.) Sector. The Buffalo Sector deployment covers 15 miles of the Upper Niagara River.

北边防项目还包括5个类似于波音交付给纽约州水牛城部的系统，水牛城部的部署涵盖了尼亚加拉河上游的15英里区域。

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Officials could close shipping connections between Lake Michigan and the upper Mississippi River system.

VOA: special.2009.12.15

We thrived along the upper Mississippi River until being forcibly removed by the US government to Indian Territory, which later became Oklahoma.

NPR: Native American Symbols: Eagle, Bison Reclaimed

The impressive views continue as it speeds alongside the cliffs and canyons of the upper Colorado River, before descending into the deserts of Utah and Nevada.

BBC: Five unforgettable rail journeys

It covers an area roughly half the size of France within the Upper Paraguay River Basin, extending over the border into Paraguay and Bolivia.

BBC: Brazil��s land of the jaguar