<html><head></head><body><div>Thank you, Anna.</div><div>r.sim.water finishes the simulation not at the end of the rainfall event, in my case at 30 minutes, but at an earlier time. In my case, in the smaller reservoir at 16 minutes, in the case of the more extensive reservoir at 24 minutes. But the water keeps coming even after that. I imagined that the calculation ends when it reaches the steady state of the water blade.</div><div>But it's not so. Then I don't understand why it ends at 16 or 24 minutes. Doesn't the water continue to arrive after that? Shouldn't it increase?</div><div>I cannot understand it. In the reservoirs, the discharge is very low, as I expect. But if the discharge does not increase and the precipitation continues, I expect the water depth to rise again.</div><div>And it is not understandable that two reservoirs, one twice the volume of the other, contain the same depth of 30 cm at the end of the rainfall.</div><div>To understand how this works, I would apply waterproofing to the reservoirs. The ksat, or infil_value, is the only variable that can explain this: the larger reservoir loses more water.</div><div>If both reservoirs were waterproof, I would have removed this variable. Unfortunately r.sim.water infil=raster where I have marked value 0 in the reservoirs does not work. There is perhaps a bug that I have reported. So I haven't had a chance to test this.</div><div>I don't know how to do it; I can't trust the 30 cm as a value to calculate the water volume in the two reservoirs. I will have to use another model.</div><div>I will try to use a distributed model. Since I have the data in GRASS, I will try using the old geomhydas, hoping the modules will work in GRASS8, and then use the Mhydas models in OpenFluid. I have no other chance unless someone can help me find a solution.</div><div><span><pre>-- <br></pre><pre>--
Perito agrario Enrico Gabrielli
progetto F.A.R.M. www.farm-agroecologia.it
Tessera n. 633 Collegio Periti agrari prov. Di Modena
Biblioteca agricoltura: https://www.zotero.org/groups/aplomb/
https://www.inaturalist.org/observations/bonushenricus
</pre></span></div><div><br></div><div>Il giorno mar, 01/08/2023 alle 09.23 -0400, Anna Petrášová ha scritto:</div><blockquote type="cite" style="margin:0 0 0 .8ex; border-left:2px #729fcf solid;padding-left:1ex"><div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Jul 31, 2023 at 11:42 PM bonushenricus <<a href="mailto:bonushenricus76@gmail.com">bonushenricus76@gmail.com</a>> wrote:<br></div><blockquote type="cite" style="margin:0 0 0 .8ex; border-left:2px #729fcf solid;padding-left:1ex"><div><div>Hi Anna</div><div>I too immediately thought it was enough to compute it for the final step of the simulation,</div><div>but I noticed that the same slope, same ditches, same rainfall, for two reservoirs at the same location, same length along a contour, but different width and depth, at the final step of the simulation the water depth was always 30 cm, I went to read the article </div><div style="line-height:1.35;margin-left:2em"><div>Mitasova, Helena, Chris Thaxton, Jaroslav Hofierka, Richard McLaughlin, Amber Moore, e Lubos Mitas. «Path Sampling Method for Modeling Overland Water Flow, Sediment Transport, and Short Term Terrain Evolution in Open Source GIS». In <i>Developments in Water Science</i>, 55:1479–90. Elsevier, 2004. <a href="https://doi.org/10.1016/S0167-5648(04)80159-X" target="_blank">https://doi.org/10.1016/S0167-5648(04)80159-X</a></div><div>where I read the Saint-Venant equation. I am an agricultural technician and geographer unfortunately ignorant of hydrological calculations and serious mathematics, and I understood, looking at the equation, that the water depth is the depth of overland flow = rainfall exces - water flow.</div><div>So the final 30 cm should not be understood as accumulated water, but as the blade of water that was added at that precise moment.</div><div>Isn't my interpretation right?</div></div></div><br></blockquote><div><br></div><div>No, it should be actual water depth. I didn't understand the discrepancy you are describing?<br></div><blockquote type="cite" style="margin:0 0 0 .8ex; border-left:2px #729fcf solid;padding-left:1ex"><div><div style="line-height:1.35;margin-left:2em"> <span title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_id=urn%3Aisbn%3A978-0-444-51840-8&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Path%20sampling%20method%20for%20modeling%20overland%20water%20flow%2C%20sediment%20transport%2C%20and%20short%20term%20terrain%20evolution%20in%20Open%20Source%20GIS&rft.publisher=Elsevier&rft.aufirst=Helena&rft.aulast=Mitasova&rft.au=Helena%20Mitasova&rft.au=Chris%20Thaxton&rft.au=Jaroslav%20Hofierka&rft.au=Richard%20McLaughlin&rft.au=Amber%20Moore&rft.au=Lubos%20Mitas&rft.date=2004&rft.pages=1479-1490&rft.spage=1479&rft.epage=1490&rft.isbn=978-0-444-51840-8&rft.language=en"></span></div><div><span><pre>-- <br></pre><pre>--
Perito agrario Enrico Gabrielli
progetto F.A.R.M. <a href="http://www.farm-agroecologia.it" target="_blank">www.farm-agroecologia.it</a>
Tessera n. 633 Collegio Periti agrari prov. Di Modena
Biblioteca agricoltura: <a href="https://www.zotero.org/groups/aplomb/" target="_blank">https://www.zotero.org/groups/aplomb/</a>
<a href="https://www.inaturalist.org/observations/bonushenricus" target="_blank">https://www.inaturalist.org/observations/bonushenricus</a>
</pre></span></div><div><br></div><div><br></div><div>Il giorno lun, 31/07/2023 alle 14.34 -0400, Anna Petrášová ha scritto:</div><blockquote type="cite" style="margin:0 0 0 .8ex; border-left:2px #729fcf solid;padding-left:1ex"><div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sun, Jul 30, 2023 at 6:01 AM bonushenricus <<a href="mailto:bonushenricus76@gmail.com" target="_blank">bonushenricus76@gmail.com</a>> wrote:<br></div><blockquote type="cite" style="margin:0 0 0 .8ex; border-left:2px #729fcf solid;padding-left:1ex"><div>Hi<br>From r.sim.water, how can I calculate the volume of water stored in<br>small water storages placed along a relief and connected to ditches?<br>In this article <a href="https://doi.org/10.1016/j.agwat.2023.108398" rel="noreferrer" target="_blank">https://doi.org/10.1016/j.agwat.2023.108398</a> these<br>Italian researchers with r.sim.water manage did this calculation, but I<br>do not understand how. With a calculation at different times on<br>discharge at the entrance to the water storage?<br>I tried to contact them, but they did not reply.<br>Thanks!<br></div><div><br></div></blockquote><div><br></div><div>Hi,</div><div><br></div><div>volume would be simple depth times cell size squared for a certain selected area. I would compute it for the final step of the simulation, I am not sure what is the purpose of summing it for different time steps. Perhaps you could clarify a little bit?</div><div><br></div><div>Anna</div><div> </div><blockquote type="cite" style="margin:0 0 0 .8ex; border-left:2px #729fcf solid;padding-left:1ex"><div><br></div></blockquote></div></div></blockquote></div></blockquote></div></div></blockquote></body></html>