世界众多江河洪水序列形成的环境背景“一致性”已不复存在，传统极值流量分析的“极值理论”需修正。东江流域变化环境后，龙川和河源站年最大日流量序列M-K检验通过0.01 显著水平，呈下降趋势。采用时间变化矩模型对年最大日流量序列作非一致性处理，选择5 种分布线型、8 种趋势模型共40 种模型进行比较。结果表明，龙川站对数正态分布搭配CP趋势（均值和标准差相关且具有抛物线趋势）模型、河源站Gumbel分布搭配CP趋势模型拟合效果最优。水文情势变化后，传统洪水重现期概念应该被修正。基于传统频率分析方法得到的100 a 一遇洪水设计值，均表现出其重现期由水利工程建设前小于100 a 一遇变化到2000 年后的大于400 a 一遇，而非100 a 一遇。若仍采用传统方法计算，两站均会高估设计洪水量级。非一致性背景下，推荐考虑现状时间基点下的洪水设计值。
No "stationarity" exists in the environmental background for the formation of many river flood series in the world any longer, and the traditional extreme value flow analysis, i.e. "extreme value theory" must be amended in order to adapt to these phenomena. The annual maximum peak flow of Longchuan and Heyuan stations in Dongjiang River Basin exhibited a decreasing trend at the significance level of 0.01 detected by Mann-kendall test after hydraulic engineering regulation. In this study, the non-stationary processing method of time-varying moments (TVM) was adopted to analyze and calculate the annual maximum daily flow series at Longchuan and Heyuan stations of the Dongjiang River Basin. Five types of distribution curves and eight kinds of trend models, for a total of 40 models, were selected for comparison. The results showed that lognormal distribution (LN2) with a CP model (CP refers to both the mean value and standard deviation have a parabolic type trend and the ratio of the two is constant) at Longchuan Station, Gumbel distribution with a CP model at Heyuan Station may obtain the optimal fitting effect. After significant changes occur to the hydrological regime, the concept of tradition flood should be amended. Based on traditional frequency analysis methods, the design value of 100-year flood was available, indicating that a return period changed from less than 100 years before hydraulic engineering construction to 400 years after 2000 at two hydrological stations, rather than 100 years, for both stations. In the context of non-stationarity, the flood design value corresponding the present time points should be recommended.
[1] Schiermeier Q. Increased flood risk linked to global warming[J]. Nature, 2011, 470(7334): 378-381.
[2] Milly P C D, Julio B, Malin F, et al. Stationarity is dead: Whither water management[J]. Science, 2008, 319(5863): 573-574.
[3] Khaliq M N, Ouarda T B M J, et al. Frequency analysis of a sequence of dependent and/or non-stationary hydro-meteorological observations: A review[J]. Journal of Hydrology, 2006, 329(3/4): 534-552.
[4] 梁忠民, 胡义明, 王军. 非一致性水文频率分析的研究进展[J]. 水科学进展, 2011, 22(6): 864-871.[LIANG Zhong-min, HU Yi-ming, WANG Jun. Advances in hydrological frequency analysis of non-stationary time series. Advances in Water Science, 2011, 22(6): 864-871.]
[5] Strupczewski W G, Singh V P, Feluch W. Non-stationary approach to at-site flood frequency modeling I. Maximum likelihood estimation[J]. Journal of Hydrology, 2001, 248(1/4): 123-142.
[6] Cunderlik J M, Burn D H. Non-stationary pooled flood frequency analysis[J]. Journal of Hydrology, 2003, 276(1/4): 210-223.
[7] 谢平, 陈广才, 夏军. 变化环境下非一致性年径流序列的水文频率计算原理[J]. 武汉大学学报: 工学版, 2005, 38(6): 6-15.[XIE Ping, CHEN Guang-cai, XIA Jun. Hydrological frequency calculation principle of inconsistent annual runoff series under Changing environments. Journal of Wuhan University of Hydraulic and Electric Engineering, 2005, 38(6): 6-15.]
[8] Waylen P, Woo M K. Prediction of annual floods generated by mixed processes[J]. Water Resources Research, 1982, 18(4): 1283-1286.
[9] Singh V P, Wang S X, Zhang L. Frequency analysis of nonidentically distributed hydrologic flood data[J]. Journal of Hydrology, 2005, 307(1/4): 175-195.
[10] Vogel R M, Yaindl C, Walter M. Nonstationarity: Flood magnification and recurrence reduction factors in the United States[J]. Journal of the American Water Resources Association, 2011, 47(3): 464-474.
[11] Villarini G, Smith J A, Serinaldi F, et al. Flood frequency analysis for nonstationary annual peak records in an urban drainage basin[J]. Advances in Water Resources, 2009, 32(8): 1255-1266.
[12] Zhang Q, Xu C Y, Yu Z, et al. Multifractal analysis of streamflow records of the East River basin(Pearl River), China[J]. Physica A, 2009, 388: 927-934.
[13] 王兆礼. 气候与土地利用变化的流域水文系统响应——以东江流域为例[D]. 广州: 中山大学, 2007.[WANG Zhao-li. Effects of Climatic Change and LUCC on Hydrological System in the East River Basin, South China. Guangzhou: Sun Yat-sen University, 2007.]
[14] Stedinger J R, Vogel R M, Foufoula-Georgiou E. Frequency analysis of extreme events[M]//Maidment D R. Handbook of Hydrology. McGraw-Hill, New York, USA, 1993: 1-18.
[15] Rao A R, Hamed K H. Flood Frequency Analysis[M]. Florida: CRC Press, 2000: 10-12.
[16] Akaike Hirotugu. A new look at the statistical model identification[J]. IEEE Transactions on Automatic Control, 1974, 19(6): 716-723.
[17] Mann H B. Nonparametric tests against trend[J]. Econometrica, 1945, 13: 245-259.
[18] Dahman E R, Hall M J. Screening of Hydrological Data[M]. Netherlands: International Institute for Land Reclamation and Improvement (ILRI), 1990: 49, 58.
[19] 涂新军, 陈晓宏, 张强. 区域河川径流量时空变异特征及成因分析——以广东省为例[J]. 湖泊科学, 2011, 23(1): 104-111.[TU Xin-jun, CHEN Xiao-hong, ZHANG Qiang. Spatia-l temporal variability patterns of regional runoffs series and their root cause analysis, Guangdong Province. Journal of Lake Sciences, 2011, 23(1): 104-111.]
