黄河的输沙量:过去、现在和将来——距今15万年以来的黄河泥沙收支表

Sediment Discharge of the Yellow River,China:Past,Present and Future—A Synthesis

黄河于150 ka BP切穿三门峡,东流入海.黄河泥沙90%来自黄土高原.黄土高原土地利用和植被的变化对黄河输沙有决定性的影响.15万年以来,黄河进入华北平原的泥沙约70 000×108 t,其中10 ka BP以前占80%.10 ka BP以后的输沙量中,最后1040年黄土高原滥垦时期占60%.黄河泥沙的归宿,建造华北大平原占73%,流入海洋占26%.现在,黄河每年流入北黄海的泥沙不足0.2×108 t,其输运主要受海洋环流系统的影响.现在黄海每年向东海输运悬浮沉积物0.2×108～0.3×108 t,主要为废黄河三角洲及水下三角洲受侵蚀再悬浮的黄河泥沙.1996-2000年黄河下游连年断流,利津站的年径流量和输沙量只有1950-1979年30年平均的19%左右.今后20～30年内,由于气候变暖、工业、城市等引黄水量增加,黄河的入海泥沙量仍将偏少.

The Yellow River cut through Sanmenxia Gorge and flowed to North China Plain and the sea in 150 ka BP. Since that time, about 70 000 × 10^8 t sediment has been discharged through Sanmenxia Gorge. Based on land use-land cover changes in Loess Plateau and other available evidence, a rough estimate of the Yellow river sediment budget is presented： about 73% build North China Plain and 26% escape to the sea. In the present, 〈 0.2 × 10^8 t/a suspended sediment of the Yellow River enter the North Yellow Sea. Their transport pattern is chiefly determined by the current system. It has been shown that only 0.2 × 10^8 ～ 0.3 × 10s^8 t/a suspended particles are carried to the East China Sea. They are chiefly resuspended sediment from erosion of the coast and subaqueous delta of the abandoned Yellow river. Since 1972, the lower Yellow river suffers from continuous no-flow. During 1996- 2000, annual water flow and sediment discharge are only 19% of the normal years （i. e. average for 1950-1979）. It is predicted that owing to global warming and increase of water diversion from the Yellow river for industrial and urban use, sediment flux of the Yellow river to the sea will most likely remain small in the next 2 - 3 decades.