| 1. | With the co - environment deterioration , the sediment transportation and concentration are increased by 4 % every 12 years from 1950 to 1985
在上游生态环境破坏程度日益加剧的情况下， 1950 1985年长江输沙量、含沙量约每12年以4 %的速率缓慢增长， 1992 1997年大量减少。 |
| 2. | There are lots of factors which influence the evolvement law of sediment discharge , and it is very difficult to be known and gained , it results in low precision of simulation and forecast
摘要影响输沙量演变规律的前期因素比较多，且难于确定和提取，这就造成对输沙量的拟合和预测精度较低。 |
| 3. | The analysis shows that the average annual runoff volume has a little increase due to human activities after management , but the average annual sediment production has greatly decreased
通过分析发现，治理后流域内的人类活动使年均径流量比治理以前略有增加，而年均输沙量却比治理以前大幅度减少。 |
| 4. | Based on analysis of chaos characteristic of sediment discharge time series , bp neural networks model based on chaos phase space is proposed to forecast the sediment discharge through embedding dimension
在对输沙量时间序列混沌特性分析的基础上，利用嵌入相空间来确定前期影响因子，建立了基于混沌相空间技术的bp神经网络模型。 |
| 5. | With all these ways , the sediment transportation and concentration of the yangtze river will be half of nowadays for a long time and close to the situation of the tang and song dynasty
治水必治沙，通过“蓄水减沙，借水攻沙”的工程措施，和坚持不懈的水土保持， “标本兼治” ，可使长江输沙量、含沙量长期减少1 / 2 ，恢复到唐宋时代水平。 |
| 6. | The result shows that annual rainfall in the 15 coming years will increase by about 6 % , annual rainfall fluctuation will increase and rainfall concentration in a year tends to increase , which will make flood and sediment increased
结果表明：未来降水量比多年平均值增加6 %左右，且年际波动性增大，年内分布更加集中，洪水量和输沙量有增大的趋势。 |
| 7. | 2 comparison with the sand transporting rate of cultivate land , cultivate afterward harrowing land and flat bare land indicate that the sand transporting quantity of cultivate land and cultivate afterward harrowing land is separately lower than - flat bare land 88 . 2 % and 66 . 2 %
2对耕翻地、耕后耙地以及平坦裸地输沙量观测，表明耕翻地与耕后耙地分别比对照平坦裸地的输沙量降低了88 . 2与66 . 2 。 |
| 8. | By analyzing the runoff and sediment characteristics of tao river basin , it can be concluded that the main sediment - yield region is loess area between lijia village and hongqi zone where sediment yield in flood season ( june to september ) is more than 81 percent of the mean averaged over years
分析了流域水沙特性：洮河流域泥沙的主要产地是李家村-红旗区间的黄土地区；汛期( 6 - 9月)输沙量占多年平均的81以上。 |
| 9. | A statistical model is developed and indicates high correlation between the accretion of modem yellow river delta and the water and sediment discharge of yellow river , and the model shows the necessary water and sediment discharge per year to ensure the equilibrium of alluvion and erosion of yellow river delta
黄河三角洲净造陆面积与黄河入海水沙量的统计模型说明，黄河三角洲冲淤动态平衡时的黄河入海径流量为71 . 93亿m ~ 3 a ，输沙量为1 . 853亿t a 。 |
| 10. | 1 - d and 2 - d model for non - uniform bedload transport are applied to compute the amount of bedload in the south branch of the changjiang estuary . it can be found that the peak value of bedload transport in a tidal cycle , computed by 2 - d model , is obviously larger than that computed by 1 - d model , which is induced by the disequilibrium of bedload transport in cross - river direction
在此基础上，将非均匀推移质公式推广到二维计算，并与一维计算结果作了对比，发现两种计算所获得的净输沙量相差不大，但二维输沙过程线峰值较一维计算要大，这正是河道内推移质运动横向不均匀性的体现。 |
