On Tue, Aug 1, 2023 at 10:23 AM bonushenricus <bonushenricu...@gmail.com> wrote:
> Thank you, Anna. > 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. > 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? > 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. > 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. > 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. > 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. > 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. > 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. > > Unfortunately I haven't had time to look at the reported issue. Perhaps you could share your data and provide exact commands and pictures, explaining very clearly what's wrong. > -- > > -- > 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 > > > Il giorno mar, 01/08/2023 alle 09.23 -0400, Anna Petrášová ha scritto: > > > > On Mon, Jul 31, 2023 at 11:42 PM bonushenricus <bonushenricu...@gmail.com> > wrote: > > Hi Anna > I too immediately thought it was enough to compute it for the final step > of the simulation, > 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 > 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 *Developments in Water Science*, 55:1479–90. Elsevier, > 2004. https://doi.org/10.1016/S0167-5648(04)80159-X > 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. > 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. > Isn't my interpretation right? > > > No, it should be actual water depth. I didn't understand the discrepancy > you are describing? > > -- > > -- > 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 > > > > Il giorno lun, 31/07/2023 alle 14.34 -0400, Anna Petrášová ha scritto: > > > > On Sun, Jul 30, 2023 at 6:01 AM bonushenricus <bonushenricu...@gmail.com> > wrote: > > Hi > From r.sim.water, how can I calculate the volume of water stored in > small water storages placed along a relief and connected to ditches? > In this article https://doi.org/10.1016/j.agwat.2023.108398 these > Italian researchers with r.sim.water manage did this calculation, but I > do not understand how. With a calculation at different times on > discharge at the entrance to the water storage? > I tried to contact them, but they did not reply. > Thanks! > > > Hi, > > 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? > > Anna > > > >
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