怒江干流水沙年内分配特征及其变化趋势

怒江研究基础严重滞后于流域资源保护与开发利用的需求。利用怒江干流贡山、道街坝和木城3个水文站历年月径流和悬移质输沙观测数据,运用集中度与集中期、Mann-Kendall检验和R/S分析等方法,研究怒江干流1964-2011年水沙年内分配时空特征及其变化趋势。结果表明:怒江干流径流呈缓慢上升趋势,但输沙上升趋势明显;怒江干流悬移质输沙年内分配集中度明显高于径流,径流和悬移质输沙年内分配集中度时间上呈波动下降趋势,空间上呈从上游到下游递减的趋势;径流和悬移质输沙年内分配多年平均集中期均在7月中旬,较降水集中期稍有提前;怒江干流径流年内分配集中度未发生突变,悬移质输沙年内分配集中度在1977年开始发生突变,在1995年后下降趋势明显;怒江干流径流和悬移质输沙年内分配集中度未来仍将延续波动下降的趋势,且悬移质输沙年内分配集中度的下降趋势比径流更强。

Feature of water and sediment allocation in annual in Nujiang river mainstream and its change trend

The research foundation of Nujiang River seriously lags behind the demand of protection and exploitation of river basin resources.The paper used the long record of monthly runoff and suspended sediment transport at the three hydrological gauge stations in Nujiang river mainstream, and applied the concentrated rate and period, Mann-Kendall test and R/S (Rescaled Range Analysis) methods to study the temporal and spatial characteristics, the change trend of runoff and sediment transport in he period of 1964 to 2011.The results showed that: the runoff in Nujiang River mainstream increased slowly, but sediment transport rise significantly; the concentrated rate of annual sediment transport allocation is much larger than that of runoff;the concentrated rate of annual runoff and sediment transport allocation appears decline trend.and in space it presents a decreasing trend from upstream to downstream; the average concentrated period of annual runoff and sediment transport allocation is in the middle July,and is slightly ahead of those of precipitation; the concentrated rate of annual runoff allocation do not produce mutation, and the concentrated rate of annual sediment transport allocation produce mutation began in 1977,and the the concentrated rate appeared the evident downward trend after 1995; In the Nujiang river mainstream, the concentrated rate of annual runoff and sediment transport allocation will still continue the fluctuation downward trend,and the downward trend of concentrated rate of annual sediment transport will be more obvious than that of runoff.