基于IGAWDU的滦河中游河道生态基流量研究

提出能计算平均年和典型年生态基流量的基于CAWDU（建设项目水资源论证导则）的代表年法（简称IGAWDU法），建立了相应的公式，应用于滦河中游典型河段。通过天然径流量趋势分析，确定自然与人为干扰的转折点，选取用于生态基流量计算的数据。采用双因素方差分析法比较逆月最小生态径流法（M—MMER法）和IGAWDU法与Tennant法的差异度。结果表明：（1）基于IGAWDU法的多年平均生态基流量为1．412亿m^3，丰、平、枯水年的年生态基流量分别为2．977亿m^3，1．736亿m^3，0．834亿m^3，占年均天然径流量32．4％，18．9％，9．1％，丰、平水年可满足维持生态系统所需基本水量；（2）M—MMER法与Tennant法的差异性较大。基于GAWDU的平均年法与Tennant法差异性不显著；（3）基于IGAWDU法的生态基流量略高于Tennant法，更利于河道生态系统健康发展，适于滦河流域生态基流量的估算。

Ecological Basic Flows in the Middle Reaches of Luanhe Basin Based on IGAWDU

As a classification method of ecological basic flows（EBFs）, the typical year method is introduced into guidelines for assessment of water- draw and utilization in construction projects （SL/Z322 -2005）（GAWDU）. This paper proposes representative year method based on GAWDU, which is called IGAWDU. Equations of IGAWDU are constructed and applied in the middle reaches of Luenhe Basin. IGAWDU consists of mean annum and typical year EBFs. Difference index and two -way ANOVA are used to analyze the degree of difference between IGAWDU and Tennant, month -by -month minimum ecological nmoff（ M -MMER）and Tennant. The resuits indicate that： （1）based on IGAWDU, mean annual EBF is 1.412 × 10^8 m^3, EBFs of wet year（p =20%）, normal year（p = 50% ）, low flow year（p = 95% ）are 2. 977 × 10^8 m^3, 1. 736 × 10^8 m^3, 0. 834 × 10^8 m^3, about 32. 4%, 18. 9% and 9. 1% of the natural river discharge respectively. EBFs of wet year and normal year can meet the basic water of aquatic ecosystem, while EBFs of low flow year is slightly lower; （2） EBF is 2.262× 10^8 m^3 based on M - MMER, airing the EBF of wet year and normal year based on IGAWDU; （3）IGAWDU is more reasonable than Tennant in the middle reaches of Luanhe Basin.