Detailed spatio‐temporal sediment supply reconstruction using tree roots data

Floods are an important geomorphic agent that accelerate sediment supply from bank failures. The quantitative proportions supplied by lateral inputs and the transport conditions of the channel can create local or extended accumulation zones within the channel reaches. These accumulation zones play an important role in the geomorphic regime of the stream. Knowledge of long‐term history of sediment supply is necessary to determine how these input and deposition forms developed. This study introduces a new approach for the quantification of past sediment supply via lateral erosion (incised banks and individual bank failures), using a case study of the confluence of three partial tributaries in the accumulation zone in the Outer Western Carpathians. For each tributary, as well as the channel reach downstream of the confluence zone, we calculated the mean of the largest bed particles and the unit stream power as indicators of transport capacity. We found that two of the tributaries supply significant amounts of sediment to the accumulation zone because of their higher unit stream power related to their higher transport potential, and observed coarser bed sediment. Seventy‐three bank failures with a total volume 395.5 m³ were mapped, and the sediment supply volume was dated using dendrogeomorphic analysis of 114 scarred tree roots (246 samples). The total volume of the dated sediment supply in the individual tributaries was 193.9 m³, whereas the volume of erosion in the accumulation zone was only 4.9 m³ for a period of approximately 30 years. The period represented by the dated tree roots included 12 years in which erosion events occurred and impacted the total sediment budget in the study area. Although sediment supply was greater than erosion in the accumulation zone, there are no present‐day signs of accretion. The rupture of a dam in an old pond (which is situated approximately 50 m below the accumulation zone) probably increased the transport conditions in the accumulation zone so that it balanced the high sediment supply from individual tributaries. Copyright © 2016 John Wiley & Sons, Ltd.     

The extended Lissajous–Levi-Civita transformation

Action-angle variables for the Levi-Civita regularized planar Kepler problem were introduced independently first by Chenciner and then by Deprit and Williams. The latter used explicitly the so-called Lissajous variables. When applied to the transformed Keplerian Hamiltonian, the Lissajous transformation encounters the difficulty of being defined in terms of the constant frequency parameter, whereas the Kepler problem transformed into a harmonic oscillator involves the frequency as a function of an energy-related canonical variable. A simple canonical transformation is proposed as a remedy for this inconvenience. The problem is circumvented by adding to the physical time a correcting term, which occurs to be a generalized Kepler’s equation. Unlike previous versions, the transformation is symplectic in the extended phase space and allows the treatment of time-dependent perturbations. The relation of the extended Lissajous–Levi-Civita variables to the classical Delaunay angles and actions is given, and it turns out to be a straightforward generalization of the results published by Deprit and Williams.     

Long-Term Stability Of Geoidal Geopotential FromTopex/Poseidon Satellite Altimetry 1993–1999

The TOPEX/POSEIDON (T/P) satellite altimeter data from January 1, 1993to October 24, 1999 (cycles 11–261) was used for investigating thelong-term variations in the geoidal geopotential W₀ and/orin the geopotential scale factor R₀ = GM/W₀ (GM is theadopted geocentric gravitational constant). The mean valuesdetermined for the whole period covered are: W₀ =(62 636 856.161 ± 0.002) m² s^-2, R₀ =(6 363 672.5448 ± 0.0002) m. The actual accuracy is limited bythe altimeter calibration error (2–3 cm) and it isestimated to be about ± 0.5 m² s^-2 (± 5 cm).The yearly variations of the above mean values are at the formalerror level. No long-term trend in W₀, representing the oceanvolume change, was found for the seven years period 1993–9 on thebasis of T/P altimeter (AVISO) data. No sea surface topography modelwas used in the solution. This revised version was published online in July 2006 with corrections to the Cover Date.     

The computation of the elastic constants of an anisotropic medium from the velocities of body waves

¶rt;m n¶rt;u nu nm n m . m¶rt; n¶rt;am nuuu am uma au muna (6) u (10). amua aumnu m m nn unam u u, m nmu ama mm (u. 2). uu nu nm ¶rt;u am mu n¶rt; uua 15mu anau u mu u nn uua mu anau. u unauu m nn ¶rt;u am mu n¶rt; uua ¶rt; 21 anau.

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Dedicated to 90th Birthday of Professor Frantiek Fiala     

Daily variations of the characteristics of beating-typePc3 (Bpc3) pulsations

Summary The spectra of nearly 100 samples of Bpc3 pulsations were computed in the X and Y components of data from the Budkov Observatory. These spectra were used to study the daily variations of the fundamental characteristics of the pulsations, the frequency f ₀ and amplitude A ₀ of the main spectral peaks. The daily variation of the ellipticity of the polarization ellipses of oscillations in frequency f ₀ was also studied in the XY-plane.Part of these results was reported at the XVth General Assembly of the IUGG, Moscow, August 1971.     

Beitrag Zur Ökonomie Der Ausnützung Von Luftaufnahmen

Résumé L'auteur décrit une combinaison de l'aérotriangulation en bloc — le bloc étant obtenu par raccordement de bandes — et de l'orthophotoplan. Ce procédé topographique largement automatisé est convenable pour un terrain montagneux et mal accessible (Fig. 1; Tab. 1, 2). L'auteur prouve par une analyse théorique de même que par des travaux expérimentaux et de routine qu'il est possible de contrôler le gauchissement des blocs à base de leurs écarts, constatés sur le recouvrement des bandes de clichés et que le nombre des points de repère est réduit au minimum (Fig. 2, 3; Tab. 1).

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Herrn Prof. Dr. Frantiek Fiala zum 90-sten Geburtstag gewidmet