[Rivers-list] Riverbed data processing for 2-dim simulation(Spain)

[Francisco Martinez Capel]

Hello again,

We have got nice TIN in several rivers, I mean that the survey was very good in
detail: in places with coarse substrate every cobble meant about 3-6 nodes, and
every boulder approximately 8-12 nodes. The average is around a node every 1m2.
Anyway when we make breaklines and the TIN in ArcView or ArcMAP, it does not
look natural, because the surrounded pieces of substrate still have many edges.

Of course, it can influence the 2-dim simulation at a microhabitat scale,
because the aquatic fauna is affected by the velocity field in a great manner
(in example, trout). We use River-2D (Peter Steffler, Univ. of Alberta) to do
physical habitat simulation, so it is a very detailed application what we do.

Some people recommend krigging, others say it does not work. Do you recommend
just IDW? Have you compared with spline or krigging in a detailed work?

Thank you in advance for further details,

Francisco Martinez Capel
Polytechnic University of Valencia
Valencia, SPAIN.

Cita de Jose Rodriguez <Jose.Rodriguez at newcastle.edu.au>:
> Dear Aina,
>
> We have done 2 and 3D modeling of rivers and we have used Tecplot for all of
> our pre and post processing, including interpolation and smoothing. Our
> experience with rivers is that linear or inverse distance interpolations are
> the ones that do best, mainly because the information grid is not
> homogeneous in the streamwise and spanwise directions. Sometimes other
> methods generate spurious topography. I can expand if you are interested.
>
> Regards
>
> José F. Rodríguez
>
> Lecturer in Civil and Environmental Engineering
> School of Engineering, The University of Newcastle
> Callaghan, NSW, 2308, Australia
> Phone: +61 2 49217376 - Fax: +61 2 49216991
> Jose.Rodriguez at newcastle.edu.au
>   _____
>
> From: rivers-list-bounces at iahr.org [mailto:rivers-list-bounces at iahr.org] On
> Behalf Of FRANCISCO MARTINEZ CAPEL
> Sent: Friday, 28 October 2005 6:37 PM
> To: afs at fisheries.org; rivers-list at iahr.org; grassam at fisheries.org
> Subject: [Rivers-list] Riverbed data processing for 2-dim simulation
>
>
>
> Dear colleagues,
>
> My name is Aina Hernández, I write you from the E.P.S. de Gandia
> (Polytechnic University of Valencia) in Spain. I am a PhD-student and I
> write you on behalf of my thesis supervisor Francisco Martínez Capel. We
> belong to the  <http://www.upv.es/informa/info/DIHMA/index_2f200i.html>
> Dept. of Hydraulic Engineering and Environment.
>
>
>
> We are dealing with different methods for interpolating and smoothing data
> of riverbed data, for hydraulic simulation with River-2D. We will compare
> some methods because we want to obtain a riverbed topography more similar to
> the real surrounded pieces of substrate. The usual TIN is a little rough and
> can have undesirable effects on the final results. We have tried with
> different methods of interpolation with ArcGIS (spline, inverse distance
> weighted, natural neighbours). We would appreciate more information about
> the software and methods recommended for the riverbed data processing for
> hydraulic simulation.
>
>
>
> Thank you very much in advance.
>
>
>
> Yours sincerely,
>
>
>
> Francisco Martínez Capel & Aina B. Hernández Mascarell
>
> E.P.S. Gandía (Universidad Politécnica de Valencia)
>
> Phone: +34 962849458 Ext. 49458
>
> aihermas at doctor.upv.es
>
>
>
>
>
> Paco Martinez-Capel
>
>  <http://www.upv.es/informa/info/DIHMA/index_2f200i.html> Dept. of Hydraulic
> Engineering and Environment
>
> E.P.S. de Gandia (Polytechnic University of Valencia)
>
> Ctra. Nazaret-Oliva s/n
>
> Grao de Gandia, 46730 VALENCIA
>
> SPAIN
>
>
>
> WEB-SITE:  <http://ttt.gan.upv.es/~fmcapel>
> http://personales.gan.upv.es/fmcapel
>
> Ph.nº. +34-96-2849458
>
> Fax nº. +34-96-2849309
>
>
>
>
>
>


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