摘要
为了研究三峡水库运用对进出库水沙条件的影响程度,利用水沙指标变化幅度公式,定量分析了三峡水库运用后2003~2009年进出库水沙指标的变幅。结果表明,三峡水库运用后,在均值上,4、5、6月的月均流量变幅最大,6、10、11月的月均含沙量和月均输沙率变幅最大,5、6、11月的月均来沙系数变幅最大;在极值上,非汛期最大流量、汛期最小含沙量、最小来沙系数和最小输沙率变幅最大;在极值之比上,汛期流量、含沙量、来沙系数和输沙率的最大/最小的变幅最大;在极值与年值之比上,汛期流量的最小/年均及非汛期含沙量、汛期来沙系数、年输沙率的最大/年均的变幅最大;在年内分布上,4、5、10月的月均流量/年均流量、5、6、8月的月均含沙量/年均含沙量和月均输沙率/年均输沙率、5、8、9月的月均来沙系数/年均来沙系数、汛期输沙率/非汛期输沙率、汛期含沙量/非汛期含沙量的变幅最大。
The water-sediment conditions flowing in and out of Three Gorges Reservoir were affected by impounding of the reservoir.The concept and equation of the rangeability of water-sediment indicator are proposed in this paper.Based on the observed data of hydrographic stations during the period 2003-2009,this paper analyzes quantitatively the rangeability of water-sediment indicator.The results demonstrate that in terms of average,the maximum rangeability of monthly average flow rate exits in April,May and June;the maximum rangeability of monthly average sediment concentration and sediment transport rate exits in June,October and November;the maximum rangeability of monthly average incoming sediment coefficient exits in May,June and November;in terms of extremum,the maximum flow rate in nonflood season as well as the minimum sediment concentration,sediment transport rate and incoming sediment coefficient in the flood season has the maximum rangeability;in terms of the ratio of the extremum to the annual average,the ratio of the minimum to the annual average of flow rate in the flood season,and the ratio of the maximum to the annual average of the sediment concentration in the non-flood season,the incoming sediment coefficient in the flood season,and the annual sediment transport rate have the maximum rangeability;in terms of annual distribution,the ratio of the monthly average flow rate to the annual average flow rate in April,May and October,the ratio of the monthly average sediment coefficient to the annual average sediment coefficient as well as the ratio of the monthly average sediment transport rate to the annual average sediment transport rate in May,June and August,the ratio of the monthly average incoming sediment coefficient to the annual average incoming sediment coefficient in May,August and September,the ratio of the sediment transport rate in the flood season to the sediment transport rate in the non-flood season,the ratio of the sediment concentration in the flood season to the sediment concentration in the non-flood season have the maximum rangeability.
出处
《水电能源科学》
北大核心
2014年第11期146-149,175,共5页
Water Resources and Power
关键词
三峡水库
水沙变化
水沙指标
变化幅度
Three Gorges Reservoir
water-sediment variation
water-sediment indicator
rangeability
