摘要
为解决生态流量标准的空间移植性、逐月和年际变异性和分级性4个属性问题,提出了一种基于FDC的改进方法。该方法基于月均流量系列的特定保证率将所有年份逐月进行丰、平、枯水年分组,基于总历时法和逐年组、逐月份的日均流量系列构建FDC,取50%,90%历时点流量作为生态流量的最优上限值和最小值,最小到最优上限之间的各级生态流量根据改进的Tennant等差数量分级思想确定。以汉江为例,将计算结果与Tennant法、改进Tennant法、7Q10法、90%保证率最枯月流量法、近10 a最枯月平均流量法、逐月最小生态径流法、最小月平均法、Q_(90)法、改进Q_(90)法、Q_(97,10)法和生态监测成果进行了对比分析。结果表明,改进FDC法的生态流量标准优于传统水文学法且十分合理,其空间移植性、时间变异性和栖息地条件的分级性都得到了充分体现,同时也避免了极端流量事件和年内分配不均的影响。
To solve four key problems existed in the current ecological flow criteria （EFC） ： spatial transferability,monthly variability, inter-annual variability and scalability, a modified flow-duration curve method is proposed. Based on specific guaranteed rates of average monthly flow series, this approach divides all the years into wet, nor- mal and dry year groups for every month; and then monthly flow-duration curves for every water year group are es- tablished based on total-period method and daily flow series, the discharges at the 50-percent-duration and 90-per- cent-duration points are respectively taken as the optimum and minimum EFC. Finally, multi-level EFC from mini- mum to optimum are established with progression idea of modified Tennant arithmetic. The new approach is tested in the Hanjiang River and compared with Tennant method, modified Tennant method, 7Q10 method, minimum monthly runoff at 90% guaranteed rate method, minimum monthly runoff for recent ten years method, month-by- month minimum ecological runoff method, minimum monthly average discharge method, Q90 method, modified Q90 method, Q97,10 method and ecological monitoring data. The results show that the new approach is reasonable and su- perior to traditional hydrological methods for excellent spatial transferability, temporal variability, gradability of perch condition, meanwhile, by the new approach, we can avoids the influence of extreme flow events and uneven intra-annual distribution.
出处
《长江科学院院报》
CSCD
北大核心
2015年第11期1-6,13,共7页
Journal of Changjiang River Scientific Research Institute
基金
高等学校博士学科点专项科研基金资助项目(20110142110064)
关键词
生态流量
流量历时曲线
空间移植性
时间变异性
分级性
极端事件
ecological flow
flow-duration curve
spatial transferability
temporal variability
gradability
extreme flow events
