摘要:

All the field “experiments” indicated in the sub-title above include the hydrological cycle in some or all of its aspects and thus require the use of “hydrological sciences”. Is hydrology actually included in them? This depends on the definition of hydrology used. The paper briefly describes the different definitions of “hydrology” in the context of the scientific objectives and concepts of these experiments and related scientific activities. It further evaluates the role actually assigned to hydrologists in past cross-disciplinary endeavours to conduct “field experiments” and goes on to propose adjustments to this role in the GEWEX Continental-scale International Project (GCIP). Related activities are analysed in some detail in this framework and proposals are presented for increased inter-disciplinary communication.

ISSN:0262-6667    

DOI:10.1080/02626669409492737

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The relative importance of data on winter snow accumulation and summer (monsoon) rainfall for estimating annual runoff in the Jhelum River basin, Punjab Himalaya, Pakistan, has been investigated. Strong correlations were found between point measurements of the annual maximum of snowpack water equivalent and of total winter precipitation in the Kunhar sub-basin, and total annual discharge. In addition, total winter snowfall showed a generally significant correlation with annual discharge. Elevation did not appear to play a strong role in determining the usefulness of these measurements, whereas location within the basin relative to large scale precipitation patterns did, in some cases. Monsoon rainfall appeared to be a very poor indicator of annual discharge. The results also suggest that the operation of a continental scale negative feedback mechanism between Eurasian snow cover and the Indian monsoon might be felt in this region of the Himalaya.

ISSN:0262-6667    

DOI:10.1080/02626669409492738

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Les transferts d'eau et de solutés sont étudiésin situdurant une campagne d'échantillonnage de 16 mois. La composition isotopique moyenne des eaux de drainage (δ18O = −7.5‰), comparée à celle des pluies pendant la période de recharge (δ18O = −8.8‰), témoigne de l'influence importante de l'eau provenant de la microporosité (δ18O = −7.0‰). En octobre 1990 cependant, l'eau de pluie qui s'infiltre rapidement au travers des fissures de dessiccation représente la majeure partie des flux drainés. L'eau est alors mobilisée dans moins de 4% du volume poral total du sol et présente des teneurs chimiques élevées. En janvier 1991, le gonflement des argiles entraîne le colmatage des fissures et l'eau circule au travers de microchenaux d'environ 30 μm. L'eau de la microporosité du sol représente plus de 80% des flux drainés et la dilution par l'eau de pluie est un phénomène progressif.

ISSN:0262-6667    

DOI:10.1080/02626669409492739

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

For a long time now, the hydrologist has been faced with the problem of finding which of the many possible probability distribution functions can be used most effectively in flood frequency analyses. This problem has been mainly due to the insufficiency of the conventional goodness-of-fit procedures when used with the typically skewed flood probability distributions. In this study, the Akaike Information Criterion (AIC) goodness-of-fit test is used to identify more objectively the optimum model for flood frequency analysis in Kenya from a class of competing models. The class is comprised of (a) seven three-parameter density functions, namely, log-normal, Pearson, log-Pearson, Fisher-Tippet, log-Fisher-Tippet, Walter Boughton and log-Walter Boughton; and (b) two five-parameter density functions, namely, Wakeby and log-Wakeby. The AIC is also used in this study as a method of testing for the existence of outlier peak-flow values in the peak annual data used. A modified version of the chi-square goodness-of-fit test is also used, but only for the sake of comparison with the AIC.

ISSN:0262-6667    

DOI:10.1080/02626669409492740

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

There are many varieties of geological hazard in China which are widely dispersed. Land subsidence is one such hazard and occurs mainly in the coastal cities of east China. Sinkhole collapses are mainly found near those cities of east and middle China that have karst water and karst water-impregnated ore deposits. Earth fissures also occur in east and middle China. All these geological hazards have a great influence upon the construction of engineering works. Though the causes of the hazards may be different, a major contributor is human economic activity. Therefore, a major countermeasure is to control human economic development.

ISSN:0262-6667    

DOI:10.1080/02626669409492741

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The Ebro Basin is located in the northeast of Spain. Its central part is filled with gypsum and carbonate deposits of Neogene age. Quaternary sediments overlie the Tertiary layers. Alluvial sinkholes have developed in this region, causing high economic losses. From the study of aerial photographs, from the compilation of historical cases of collapse and from data on the lithological characteristics of the Quaternary and Tertiary deposits (their structure, morphology, hydrological characteristics, etc.), natural and human factors in sinkhole development have been evaluated. Among the natural variables that may be considered are the lithology of the Tertiary deposits, the thickness and geomechanical behaviour of the Quaternary cover, the morphology of the contact between the Tertiary and Quaternary deposits, fracturing, content of sulphates in groundwater and the depth and seasonal variations of the groundwater level. The irrigation techniques of farmers and the presence of irrigation canals increase the level of the groundwater. Pumping activities may also be important locally.

ISSN:0262-6667    

DOI:10.1080/02626669409492742

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

A type-curve matching method is presented for the determination of aquifer parameters from water level observations in a finite confined aquifer and discharge measurements at a line sink where there is a constant drawdown. An existing solution in the literature (in the form of complementary error functions) to the one-dimensional nonsteady flow towards a line sink under constant drawdown in a confined aquifer of finite width has been used to define a drain function and to construct a family of type-curves. An application of the method is given.

ISSN:0262-6667    

DOI:10.1080/02626669409492743

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626669409492744

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626669409492745

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626669409492747

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor