摘要:

Leakage properties and the potential for land subsidence due to groundwater withdrawal from a multi-aquifer water supply system were investigated by applying leaky type curve and one dimensional consolidation models to drawdown data that were obtained during a pumping test experiment in an aquifer-aquitard system. The producing aquifer has transmissivity and storativity values of 5.3 × 10−3m2s−1and 9.54 × 10−4respectively. It is recharged through leakage at a rate of 5.67 × 10−8m s−1, giving a leakage amount of more than 0.007 m3s−1. Drainage of the aquifer-aquitard system could result in aquitard compaction of between 50 and 180 mm year−1for pumping periods of 6 and 22 h day−1, respectively. The observed leakage has important implications for land subsidence problems and waste disposal practices in the area.

ISSN:0262-6667    

DOI:10.1080/02626669209492623

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Data collected over a 14 year period (1977–1990) at three river stations have been used to study long term behaviour, trends and possible future changes of water temperature in the Exe Basin, Devon, UK. Long term mean temperatures are influenced by site elevation and catchment land use. Seasonal variation approximates a simple sine-generated curve and diurnal fluctuation is greater in spring than in autumn months. Significant rising trends were evident for the majority of water temperature parameters investigated and were related to air temperature changes and land use effects. Coupling of possible scenarios for future air temperature change with relationships between mean air and water temperatures and between extreme and mean water temperatures, suggests that significant increases in stream temperatures may occur by the middle of the next century, especially in small upland catchments during summer months.

ISSN:0262-6667    

DOI:10.1080/02626669209492624

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

L'étude systématique des données d'exhaure minière sur 24 sièges miniers pour la période 1945–1985 dans le bassin ferrifère lorrain montre l'existence de deux types de mines: mines à comportement stationnaire et non stationnaire. Cette hétérogénéité dans l'espace est liée aux conditions géologiques, topographiques et structurales. Un modèle général reliant l'exhaure(Q1)corrigée de l'extraction cumulée (S1) à la pluie efficace(E1)est proposé sous la forme d'une équation de convolution:

ISSN:0262-6667    

DOI:10.1080/02626669209492625

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Saturated hydraulic conductivities of Varempere series soils (plinthaqualf) located in the sudan savannah zone of Ghana were measured by the falling head method and compared with values estimated by the texture-based equation of Rawls et al. (1982). The comparisons indicated that saturated hydraulic conductivity values estimated using the texture-based equation could predict those measured within the same order of magnitude only for the coarse-textured soil. For the fine textured soils, the texture-based equation underestimated the measured values by approximately one order of magnitude. It was concluded that in modelling hydrological processes such as infiltration in coarse-textured soils, the use of the texture-based equation would be useful. However, for technical designs of irrigation and drainage systems that require more accurate information on saturated hydraulic conductivity, the use of the texture-based equation should be discouraged.

ISSN:0262-6667    

DOI:10.1080/02626669209492626

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

This paper deals with adaptive flow forecasting from discharge observations, with catchment rainfall as an additional input component. The precipitation input is pre-processed by approximate expressions of excess rainfall and routed by a linear cascade model. The basic equations of the algorithm and the general pattern of the computer program are presented. Examples are given for a case study area (Västerdalälven River in Sweden) where rainfall input in addition to the flow observations was used to improve the forecast accuracy. The results are discussed.

ISSN:0262-6667    

DOI:10.1080/02626669209492627

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Available data on suspended sediment transported by rivers in the Maghreb are reviewed for 130 drainage basins. These data allow a new estimate to be proposed for the delivery of river sediment to both the Atlantic Ocean and the Mediterranean Sea from the Maghreb region. The influences of several environmental factors (precipitation, runoff, drainage area size and lithology) on mechanical erosion and fluvial sediment transport are analysed. Finally, a multiple regression model is proposed to estimate the river sediment yields in the Maghreb.

ISSN:0262-6667    

DOI:10.1080/02626669209492628

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626669209492629

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626669209492630

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626669209492631

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626669209492632

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor