摘要:

Par l'application d'un modèle bayesien sur une série chronologique de débits observés sur la rivière Sainte-Anne du Nord, il a été possible d'identifier l'influence de la mise en eau et de l'exploitation de quatre réservoirs sur les séries mensuelles en terme d'un changement δ dans la moyenne au moment τ L'application du même modèle aux séries de deux bassins témoins a permis d'identifier parmi ces changements ceux qui sont attribuables è des variations climatiques régionales.

ISSN:0262-6667    

DOI:10.1080/02626668309491975

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Suspended sediment and dissolved load were measured in two upland piedmont gravel-bedded streams for one year. In addition, the input of major cations from precipitation and the cation content of springs within the basins were monitored. The dynamics of the suspended load through a series of storm flows are examined in relation to sediment supply and progressive exhaustion effects. The variation in the grain size of the inorganic fraction of the particulate load during the passage of the floods is detailed and variations in the organic content of the load assessed. Two distinct models of dissolved cation concentration response to stream discharge variations are proposed which reflect differences in basin geology. Finally total load calculations are presented for the year.

ISSN:0262-6667    

DOI:10.1080/02626668309491976

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The hydrological response patterns of some third order rivers in southwestern Nigeria are described in terms of regime, discharge variability and recession of flow from peak discharge in the rainy season to the lowest discharge in the dry season. The maximum and minimum discharges of the rivers coincide with the rainy and dry seasons respectively. Most of the rivers exhibit erratic flow with quick responses to storms and storm water abating quickly, while some have a very low groundwater contribution to streamflow, a phenomenon which accounted for their drying up for considerable periods in the year. The variability indices of discharge of the rivers range from 0.25 to 2.12 while the recession constants range from 0.64 to 0.98. The variability indices are much higher than those of basins of similar size reported from other studies. Three types of rivers are recognizable on the basis of their hydrological response patterns. It is observed that the nature of the surficial and solid geology has a greater influence on discharge characteristics than other factors such as depth of regolith and rainfall.

ISSN:0262-6667    

DOI:10.1080/02626668309491977

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The effect of the downstream boundary condition on the flow in a channel reach as predicted by the linear diffusion analogy model is analysed by both Laplace transformation and by modal analysis. In each case the solution takes the form of an infinite series. It is shown that the series based on Laplace transformation is highly convergent for small times and the series based on modal analysis is highly convergent for medium and longer times.

ISSN:0262-6667    

DOI:10.1080/02626668309491978

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The Hays Glacier of Enderby Land is a small Antarctic outlet glacier with a “sack-shape” source region of as yet not exactly known southward extent and area (approximately 104km2). It has a uniform or slightly wavy longitudinal profile, an approximately 7 km wide calving front between 46°15’ and 46°20′E, and a partly floating glacier tongue, extending to the seasonally changing front (classification 424 118 according to UNESCO-IAHS, 1970). The longitudinal mean surface slopes are 5–8 m km−1on the tongue, 20–30 m km−1in the step-shaped central section, and 8–12 m km−1in the entrance region. The glacier is bordered to 15 km south of the front by about 500-m-wide serac belts, associated in some places with pressure ridges. It is distinctly separated from the continental ice sheet by three rock walls on the eastern edge. At the western edge the glacier has a secondary influx region of 40 km3area which is crevassed and feeds a well-defined tributary into the left part of the glacier tongue. The average flow direction of the glacier is north, changing to northnorthwest at the front. The outflow velocity is of the order of 1000 m a−1, and the annual iceberg production in Spooner Bay (the southeastern section of Alasheev Bay in the Cosmonaut Sea) is approximately 3 km3. The dynamic conditions along the glacier are inferred from geodetic, strain, and accumulation measurements, and using a modelled internal temperature distribution.

ISSN:0262-6667    

DOI:10.1080/02626668309491979

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

In order to design micro-catchment water harvesting systems in the Indian desert, rainwater infiltration experiments were conducted on a representative loamy sand soil for a period of six years. Plots with three slopes—0.5, 5 and 10%, and five slope lengths—5.12, 7.0, 8.5, 10.75 and 14.5 m were used. With dry antecedent soil conditions, infiltration is governed by rainfall depth, whereas with wet antecedent soil conditions, raindrop impact (intensity) which forms a crust over the soil surface, is the deciding factor. Infiltration decreases significantly with increasing slope due to reduction in the time available for rainfall to infiltrate, but slope length has no significant effect. A graphical multiple curvilinear model to predict rainfall infiltration using rainfall and basin characteristics is developed and the goodness of fit is tested.

ISSN:0262-6667    

DOI:10.1080/02626668309491980

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626668309491981

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626668309491982

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626668309491983

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0262-6667    

DOI:10.1080/02626668309491984

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor