Sediment load কী?

Example 23.4 (The Mississippi)

Before 1900, the Missouri–Mississippi river system carried about 400 million tonnes of sediment a year to the sea, from a basin of about $2\,980\,000\,\mathrm{km}^{2}$. With the dissolved load, $400/0.85 \approx 471$ million tonnes, that is $4.71 \times 10^{11}/2830 \approx 1.66 \times 10^{8}\,\mathrm{m}^{3}$ of rock a year. Spread over $2.98 \times 10^{12}\,\mathrm{m}^{2}$, it is a layer

Between 1987 and 2006 the river carried only 145 million tonnes a year, which gives about $20\,\mathrm{m}/\mathrm{Myr}$: dams built on the Missouri in the 1950s trap about 100 to 150 million tonnes a year, and other works hold back more.