Regionalization of unit hydrograph parameters: 1. Comparison of regression analysis techniques     

Y. -K. Tung  K. -C. Yeh  J. -C. Yang 《Stochastic Environmental Research and Risk Assessment (SERRA)》1997,11(2):145-171

Hydrologic regionalization is a useful tool that allows for the transfer of hydrological information from gaged sites to ungaged sites. This study developed regional regression equations that relate the two parameters in Nash's IUH model to the basin characteristics for 42 major watersheds in Taiwan. In the process of developing the regional equations, different regression procedures including the conventional univariate regression, multivariate regression, and seemingly unrelated regression were used. Multivariate regression and seeming unrelated regression were applied because there exists a rather strong correlation between the Nash's IUH parameters. Furthermore, a validation study was conducted to examine the predictability of regional equations derived by different regression procedures. The study indicates that hydrologic regionalization involving several dependent variables should consider their correlations in the process of establishing the regional equations. The consideration of such correlation will enhance the predictability of resulting regional equations as compared with the ones from the conventional univariate regression procedure.  相似文献   

中国公路自然区划的回顾与展望     

苗英豪  王秉纲  MIAO Yinghao  WANG Binggang 《地理学报(英文版)》2004,14(Z1)

1IntroductionHighway, as a kind of man-made structure, will become a part of the geographical environment and be impacted by all sorts of natural factors after it is finished. On the other hand, highway also brings some changes to the geographical environment. A highway often passes through different natural regions, so it must be adaptable to any geographical environments. On the basis of deep understanding of the geographical environment, service life and normal level of the highway can be e…  相似文献   

优化K means算法在中国近海气候区划中的应用     

张慧  翟宇梅 《气象科技》2017,45(4):750-755

利用我国近海多年的风、浪及温湿资料,采用DB指标和最大距离法相结合的优化K-means聚类算法,对冬季我国近海进行气候区划,避免了传统K-means算法中确定聚类数目和初始聚类中心的主观性。结果表明,冬季我国近海可被划分为3个区域:1区主要包括28°N以北的海域以及我国东南沿海的一条狭长区域,2区主要包括台湾周边海域、台湾海峡、巴士海峡以及自越南东南部起由西南部向东北部的南海大部分海域,3区则主要包括台湾岛西南部海域、北部湾、广东沿海以及南海东南部。根据给出的区划指标,分析各分区的气候特征及其对海上舰船航行和出海人员的影响,判定1区为基本适宜区,2区为不适宜区,3区为适宜区。  相似文献   

A methodology for regionalizing 3‐D effective porosity at watershed scale in crystalline aquifers          下载免费PDF全文

Benoît Dewandel  Yvan Caballero  Jérôme Perrin  Alexandre Boisson  Fabrice Dazin  Sylvain Ferrant  Subash Chandra  Jean‐Christophe Maréchal 《水文研究》2017,31(12):2277-2295

An innovative approach for regionalizing the 3‐D effective porosity field is presented and applied to two large, overexploited, and deeply weathered crystalline aquifers located in southern India. The method derives from earlier work on regionalizing a 2‐D effective porosity field in that part of an aquifer where the water table fluctuates, which is now extended over the entire aquifer using a 3‐D approach. A method based on geological and geophysical surveys has also been developed for mapping the weathering profile layers (saprolite and fractured layers). The method for regionalizing 3‐D effective porosity combines water table fluctuation and groundwater budget techniques at various cell sizes with the use of satellite‐based data (for groundwater abstraction), the structure of the weathering profile, and geostatistical techniques. The approach is presented in detail for the Kudaliar watershed (983 km²) and tested on the 730 km² Anantapur watershed. At watershed scale, the effective porosity of the aquifer ranges from 0.5% to 2% in Kudaliar and between 0.3% and 1% in Anantapur, which agrees with earlier works. Results show that (a) depending on the geology and on the structure of the weathering profile, the vertical distribution of effective porosity can be very different and that the fractured layers in crystalline aquifers are not necessarily characterized by a rapid decrease in effective porosity and (b) that the lateral variations in effective porosity can be larger than the vertical ones. These variations suggest that within a same weathering profile, the density of open fractures and/or degree of weathering in the fractured zone may significantly vary from a place to another. The proposed method provides information on the spatial distribution of effective porosity that is of prime interest in terms of flux and contaminant transport in crystalline aquifers. Implications for mapping groundwater storage and scarcity are also discussed, which should help in improving groundwater resource management strategies.  相似文献   

Estimation of instantaneous peak flow from maximum mean daily flow by regionalization of catchment model parameters          下载免费PDF全文

Jie Ding  Uwe Haberlandt 《水文研究》2017,31(3):612-626

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水文模型参数区域化研究进展     

孙周亮  刘艳丽  陈鑫  舒章康  吴厚发  王婕  鲍振鑫  王国庆 《水文》2023,43(4):1-7

参数区域化方法是解决资料缺乏地区水文模拟和预报的有效手段,主要包括回归法、空间邻近法和属性相似法三类方法,可将有资料流域的水文模型参数移用到资料缺乏流域。首先回顾了区域化方法的基本原理和应用方法,并分析了三类主要区域化方法的适用性。从流域特征因子、水文模型及参数、不确定性探讨三个方面综述了区域化方法的研究进展。分析发现,当前区域化方法缺乏完善的理论基础,流域特征因子选择存在主观性,水文模型及参数的适用性方面研究不足。最后展望了未来的研究重点：（1）多维度适用性比较;（2）水文过程和参数的空间分布规律;（3）参数的尺度问题;（4）参数区域化的不确定性问题。  相似文献   

MMO: An improved estimator for log-Pearson type-3 distribution     

Fang X. Yu  Babak Naghavi  Vijay P. Singh  Guang-Te Wang 《Stochastic Hydrology and Hydraulics》1994,8(3):219-231

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中国主要自然致灾因子的区域分异   总被引：34，自引：2，他引：34  

史培军  王静爱 《地理学报》1994,49(1):18-26

依据１０２种自然致灾因子分布图，以县域为统计单元，建立了全国自然致灾因子数据库。在此基础上，绘制出中国自然致灾因子多度、相对强度、被灾指数图，进而分析了它们的区域分异，为进行中国自然灾害区划提供依据。  相似文献   

辽宁海洋综合经济区划分的初步探讨   总被引：4，自引：0，他引：4  

张耀光 《地理学报》1994,49(2):139-148

我国是海洋大国，有相当陆域国土面积三分之一的海洋国土。随着海洋资源的开发利用，海洋经济不断发展，海洋经济区逐渐形成。在全国划分经济区时，不应忽视海洋经济区。沿海省区在划分经济区时，更应把海洋列入到省级经济区内。辽宁是我国沿海省区之一，通过对辽宁海洋经济区划分的研究，探讨海洋经济区及其划分的有关理论、实践与方法。  相似文献   

西藏南部中白垩世旋回地层学     

陶然  曾允孚 《沉积学报》1995,13(1):18-26

根据旋回特征可把西藏南部的中白垩纪地层分为四个等级。第一级旋回主要是大套的碎屑岩与碳酸盐岩的交替，以及生物种类的变化，表现了当时海平面周期性变化。第二级旋回代表了古生产率和氧化还原的韵律性变化，通过对ＣａＣＯ₃含量的ＡＲ-ＦＦＴ处理得出的周期（ＺＭａ）与Ｂｅｒｇｅｒ等人所计算的理论周期基本相符。因此，可以认为这种旋回根本原因是因轨道参数变化所引起的古环流改变所造成，如地中海型环流与河口型环流的互换，必将导致古生产率以及海洋水体性质的改变。第三级旋回表现为层偶的变化，如泥岩与灰岩互层以及黑色页岩与灰岩互层，在本区主要有三个周期:４.３、５.２和９.２万年，它们分别相当于斜率（ε）和偏心率（Ｃ）的理论周期值，旋回的周期主要是因为气候的变化引起陆源物质的稀释作用发生周期性变化，气候的周期性变化是由于轨道参数的改变而引起，因此，这种族回具有全球的可对比性。第四级旋回是由于海水里季节性变化所引起的纹层状层理。  相似文献