35 2 Vol.35No.2 2015 3 TROPICAL GEOGRAPHY Mar.2015 GUAN ShuaiZHA XiniDING BoLIN YingyanZHUO WenshanLIU ZufaWetness-Dryness Encountering of Runoff of the Pearl River Basin Based on Copula Functions[J]Tropical Geography2015352208-217
Fig.1 The study area and location of hydrological stations C n u 1 u 2 u n φ φu 1 φu 2 φu n ( 1) ( 1) ϕ ( t), 0 t ϕ(0) ϕ ( t) = 0, ϕ(0) < t < φ φ φ u 1 u 2 u n φ
x i 2 τ = sign ( xi x j)( yi y j) n( n 1) 1 i< j n x 1 y 1 x 2 y 2 x n y n P f P k X i X Pf X i X Pk X Pk X i X Pf X Pf Y Pf u Pf v Pf u Pf v Pf X Pf Y Pk v Pk u Pf v Pk X Pk X Pf Y Pf u Pf u Pk u Pf v Pf u Pk v Pf X Pf Y Pf Z Pf u Pf v Pf w Pf u Pf v Pf u Pf w Pf v Pf w Pf u Pf v Pf w Pf X Pf Y Pk Y Pf Z Pk v Pf w Pk v Pk w Pk u Pf v Pf w Pk u Pf v Pf w Pk X i X Pf X Pk u Pf v Pf w Pf u Pk v Pk w Pk X Pf Y Pf Z Pf X Pk Y Pk Z Pk
Tab.1 The fit test results of the marginal distributions of runoff of the three major river systems D c Tab.2 Parameter estimations of 2-dimensional joint distributions of any two of the three major river systems
Tab.3 Parameter estimations and the fit test results of 3-dimensional Gumbel-Hougaard joint distributions of the three major river systems Fig.2 The joint distributions (a-i, b-i, c-i) and joint probability (a-ii, b-ii, c-ii) of annual runoff of any two of the three major river systems
xory Fig.3 The contour map of joint probability of annual runoff of any two river systems [a, c, e: P (XxorYy); b, d, f: P (XxorYy)]
Fig.4 The contour map of joint probability of annual runoff of any two river systems[p(xx, Yy)]
Tab.4 The wetness-dryness encountering probabilities of any two river systems runoff of different periods Tab.5 The wetness-dryness encountering probabilities of the three river systems runoff in different periods
喆 啟 燊
Wetness-Dryness Encountering of Runoff of the Pearl River Basin Based on Copula Functions GUAN ShuaiZHA XiniDING BoLIN YingyanZHUO WenshanLIU Zufa Center for Water Resources and EnvironmentSun Yat-sen University//Key Laboratory of Water Cycle and Water Security in Southern China of Guangdong Higher Education InstitutesGuangzhou 510275China Abstract: The Pearl River Basin holds an important economic, political and social status in China. The runoff of the Xijiang river,beijiang river and Dongjiang river affects the regional flood safety and the safety of drinking water directly. Considering the critical requirement of unified schedule of the Pearl River, this paper constructed 2-dimensional and 3-dimensional joint distributions of runoff of the three river systems based on copula functions, and analyzed their wetness-dryness encountering probability. The basic conclusions are obtained as follows:1) the synchronous wetness-dryness probabilities of any two rivers are higher than the asynchronous ones (except the Xijiang and the Dongjiang in flood seasons). The synchronous wetness-dryness probabilities of the Xijiang and Beijiang, or the Xijiang and Dongjiang are relatively small, which offers the possibility of wetness-dryness compensation between the Xijiang and the other two rivers. 2) The 3-dimensional joint distribution indicates that the synchronous wetness-dryness probabilities of the three rivers on annual scale, in flood seasons and non-flood seasons are 40.16%, 38.11% and 36.49%, respectively, with the probability of synchronous wetness and dryness much larger than that of synchronous normal ones. 3) By the joint distributions constructed above, we can get the probabilities of any runoff combinations of the three rivers, as well as diverse runoff combinations under certain probabilities. And all of those will provide important reference for unified schedule of the Pearl River. Key words: multivariate hydrological analysis; copula functions; wetness-dryness encountering; the Pearl River Basin Abstract ID Analysis System of Historical and Geographical Situation in the South China Sea Based on WebGIS ZOU Wei 1,3 LIU Yongxue 1,2 LI Manchun 1,2 WANG Yecheng 1,3 ZHOU Minxi 1,3 1Jiangsu Provincial Key Laboratory of Geographic Information Science and TechnologyNanjing 210023China2Collaborative Innovation Center for the South China Sea StudiesNanjing 210023China3School of Geographic and Oceanographic SciencesNanjing 210023China Abstract: Considering the serious situation in the South China Sea and the character of GIS system, the research designs and implements an analysis system of historical and geographical situation. This system is developed by Visual Studio 2010 with Microsoft SQL Server Database and ArcSDE Spatial Database Engine based on ArcGIS Engine technology. It is composed of four modules: the Historical and Geographical Situation Analysis module, the Islands Analysis module, the Oil Analysis module and the System Management module. In addition, this system summarises the changing of historical situation, islands situation and oil situation in the South China Sea. It can offer some firm support for decision-making and solutions of conflicts in the South China Sea. Key words: the South China Sea; historical geography; situation analysis; system design; WebGIS