Generic styles of mainstream response to lateral inputs are investigated using a one-dimensional sediment routing model with multiple grain size fractions. Numerical experiments isolate the effects of 3 parameters : ratio of tributary to mainstream
water flux, ratio of tributary to mainstream bedload flux, and ratio of tributary to mainstream bedload diameter. The primary distinction is between junctions that aggrade, causing local profile convexity with interrupted downstream fining, and junctions
that degrade. The AA. concentrate here on geomorphological aspects of the results.
Transport and deposition of fine sediment in open channels with different aspectratios
This paper investigates by means of several large eddy simulations how the channel aspectratio affects the transport and settling of suspended sediments. The numerical method is successfully validated using data of a physical experiment of fine
sediment net deposition in an open channel flow. The channel aspectratio, A, is known to be the determining factor for the development, strength and distribution of the turbulence-driven secondary flow, and it is demonstrated that A influences the primary
the cross-section. While the channel aspectratio has a large influence on the distribution of suspended sediments within the cross-section, its effect on the cross-sectional averaged deposition is negligibly small.
Stable isotope ratios of carbon in phytoliths as a quantitative method of monitoring vegetation and climate change
The purpose of this work is to explore the possibility of using the stable isotopic composition of carbon in phytoliths to reconstruct aspects of paleoenvironmental conditions. The basis for this approach is related to the influence of climate
of the taller rock columns has occurred largely within the Pleistocene and continues into the Holocene. Joint spacing is at least as important a determinant of column aspectratios as the ratio of vertical to horizontal erosion rates.
Investigations on the ratio of direct and global radiation amounts| part III
The object of the paper is to investigate which are the slope angles for which, on a northern slope, the ratio of the amounts of global radiations may be approximated by using the ratios of the amounts of direct radiations. (CK).
Sex ratio and niche differentiation in spinach (Spinacia oleraceaL.)
Densité de population ; Différenciation sexuelle ; Dynamique des populations ; Ecologie ; Ecologie végétale ; Géographie physique ; Niche écologique ; Phytogéographie ; Plante dioïque ; Sex ratio ; Spinacia oleracea
La croissance des plants mâles et femelles de Spinacia oleracea L. vas. Viking est affectée différemment par la densité de population et ceci se traduit dans le sex ratio.
Landslide susceptibility mapping at central Zab basin, Iran : A comparison between analytical hierarchy process, frequency ratio and logistic regression models
The aim of this study is to compare the landslide susceptibility mapping models of logistic regression (LR), analytical hierarchy process (AHP) and frequency ratio (FR) applied in the central Zab basin (West Azerbaijan—Iran). Eight factors were used
for landslide susceptibility mapping including slope, aspect, land cover, precipitation, lithology and the distance to roads, drainage, and faults that affect the occurrence of landslides. GIS tools and satellite images (Landsat ETM + and SPOT 5) are also used
for alluvial systems. Discharge, sediment supply (quantity and calibre) and valley gradient are accepted as independent governing variates. The model is used to define a dimensionless alluvial state space characterized by aspectratio, relative roughness
Wind tunnel experiments were conducted to investigate the effects of topography on the grain size characteristics of aeolian dust deposits. Experiments were performed on 3 isolated hills having various size and aspectratios. The longitudinal
Cette étude traite de l'analyse multitemporelle des caractéristiques territoriales et du contrôle des potentialités déduits de l'imagerie satellitaire à une échelle régionale, en considérant les aspects du ratio coûts/bénéfices. La zone d'étude de
3000 km2 comprend la lagune de Karavastase et une partie des bassins hydrographiques de Shkumbini et Devolli en Albanie centrale. Etude de 4 principaux aspects: couvert végétal, érosion, écologie des lagunes et morphologie côtière, quantités de
An investigation of element ratios for assessing suspended-sediment sources in small agricultural basins
In this study, 253 element ratios were assessed to determine which, if any, were potentially useful for sediment-source determinations in 6 small agricultural basins in northeastern Kansas, USA. Samples of surface soils (cropland and grassland
), channel banks, and reservoir bottom sediments were collected, analyzed for 23 elements, and compared. Of the 253 element ratios assessed, only the Co/Pb and Co/Zn ratios were substantially and consistently different between the channel banks and surface
soils for all 6 basins. The results show that additional research is needed to ascertain whether or not the use of Co/Pb and Co/Zn ratios as tracers is widely applicable or restricted to specific terrestrial environments.
Oxygen isotope ratios from tree rings containing compression wood
During studies of oxygen isotope : temperature relationships for tree rings in the Canadian Rockies, the AA. noted differences in oxygen isotope ratios between samples from compression wood and normal radii in the same stem. This paper briefly
Falu-varos aranyok Kelet-Kozép-Europaban (Rural-urban ratios in East-Central-Europe)
The relatively high ratio of rural population in East-Central-Europe is not indicative of backwardness, but a normal corollary of the peculiar urbanization in the region. The characteristics of the special path of progress are outlined. - (DLO)
Modelling the determinants of swing ratio and bias in US House elections 1850-1980
The AA. distinguish two important features of the seats-votes relationship that are often confounded : swing ratio and partisan bias. They are a product of the shape of the constituency partisan distribution.