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#201
08/19/2004, 03:53 PM
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There are lots of recent studies of the bay of Finland, for example, and they show phosphate being stored and released from sediments where the iron level is as high as, or higher then the phosphorus (shown below).
So again, I take these sorts of mechanisms to be interesting, but not likely relevant. Binding of phosphate in sediment accumulation areas of the eastern Gulf of Finland, Baltic Sea. Lehtoranta, Jouni; Pitkaenen, Heikki. Finnish Environment Institute, Helsinki, Finland. Hydrobiologia (2003), 492 55-67. Abstract The relations between P and components binding P were studied by analyzing the concns. of N, P, Fe, Mn, Ca and Al in sediments and pore water along the estuarine transect of the River Neva in August 1995. The high sediment org. matter concn. resulted in low surface redox potential and high pore-water o-P concn., whereas the abundance of amphipods resulted in high surface redox potentials and low pore-water o-P concn. However, despite the variation in sediment org. matter and the abundance of amphipods, very reduced conditions and slightly variable concns. of TP (0.7-1.1 mg/g DW) were obsd. in the 10-15 cm sediment depth along the estuarine gradient, indicating that the pools of mobile P were largely depleted within the depth of 0-15 cm. Multiple regression anal. demonstrated that org. matter and TFe concn. of the sediment were closely related to the variation in TP concn. of the sediments (r2 =0.817, n=32). The high total Fe:P ratio suggested that there is enough Fe to bind P in sediments along the estuarine gradient. However, low Fediss concns. in the pore water of reduced sediment (redox-potential <-50 mV) indicated efficient pptn. of FeS (FeS and FeS2), incapable to efficiently bind P. Consequently, the low Fediss : o-P ratio (<1) recorded in pore water in late summer implied that Fe3+ oxides formed by diffusing Fediss in the oxic zone of the sediments were insufficient to bind the diffusing o-P completely. The measured high o-P concns. in the near-bottom water are consistent with this conclusion. However, there was enough Fediss in pore water to form Fe3+ oxides to bind upwards diffusing P in the oxic sediment layer of the innermost Neva estuary and the areas bioturbated by abundant amphipods. Benthic release of phosphorus and its relation to environmental conditions in the estuarial Gulf of Finland, Baltic Sea, in the early 2000s. Pitkanen, Heikki; Lehtoranta, Jouni; Peltonen, Heikki; Laine, Ari; Kotta, Jonne; Kotta, Ilmar; Moskalenko, Pavel; Makinen, Anita; Kangas, Pentti; Perttila, Matti; Kiirikki, Mikko. Finnish Environment Institute, Helsinki, Finland. Proceedings of the Estonian Academy of Sciences, Biology, Ecology (2003), 52(3), 173-192. Abstract After the mid-1990s the phosphorus concns. and budget of the Gulf of Finland were strongly affected by the enhanced benthic P input caused by reduced conditions at the sediment-water interface. Esp. in late summers and autumns of 1996 and 2001 the total areas of reduced bottom sediments were large enough to affect the P concns. of the whole gulf. The total benthic release of phosphate-P, on an annual level, can be several times higher than the bioavailable P load from the catchment of the gulf. The area of reduced surface sediments varies considerably both spatially and from year to year, esp. in the relatively shallow eastern gulf. The intensity of the internal P loading is greatly controlled by vertical stratification, bottom topog., org. matter content of the sediment surface layer, and the abundance of benthic fauna. Evidently the sediment efflux can strongly affect the annual P balance and dynamics of the Gulf of Finland and counteract the decreases in the external P loading. This is verified both by inter-annual concn. changes and exptl. results. The only way to reduce the benthic release of nutrients is to decrease primary prodn. and the succeeding sedimentation of org. matter via further cutting external nutrient inputs both directly to the Gulf of Finland and to the Baltic Proper, which is an important source of nutrients for the gulf. Dissolved iron : phosphate ratio as an indicator of phosphate release to oxic water of the inner and outer coastal Baltic Sea. Lehtoranta, Jouni; Heiskanen, Anna-Stiina. Finnish Environment Institute, Helsinki, Finland. Hydrobiologia (2003), 492 69-84. Abstract Pore water concns. and benthic fluxes of dissolved Fe, P and N were measured at 2 coastal basins in the Gulf of Finland, northern Baltic Sea, during a seasonal cycle. The bioturbated inner coastal basin, where exchange of near-bottom water is efficient, had a better ability to retain P in sediments than the outer basin, where near-bottom water O concn. decreases during summer. Under the presence of O high pore water dissolved Fe:P ratio (>3.6 w : w) in surface layer of the sediment, measured esp. in winter, indicated negligible or low P-release and high N:P ratio in the efflux. On the contrary, low Fe:P ratio (<3.6), measured in summer and autumn, indicated high efflux of P and low N:P flux ratio. The low dissolved Fe:P ratio suggested that there was not enough diffusing Fe to form Fe3+ oxide-rich layer in the oxic surface zone of the sediments or near-bottom water to bind the P diffusing from the sediment. However, in sediments bioturbated by the abundant bivalve Macoma baltica, small efflux of P were measured almost throughout the study period. Thus, the Fe:P ratio cannot alone explain the P-release in bioturbated sediments. The low N:P ratio in the efflux measured in summer and autumn partly explains the measured low N:P ratio in the near-bottom water and thus N limitation of primary prodn. in the Gulf. It is evident that the release of P in the Gulf itself is of great importance for the trophic state of the Gulf of Finland.
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#202
08/19/2004, 04:08 PM
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Mike |
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#203
08/19/2004, 04:56 PM
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i dose iron and use phosban..........i would think using phosban would be good for the sandbed cuz it would keep phos levels down to begin with, i dont know where iron comes into play, most of what these guys are discussing goes over my head really =(
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#204
08/19/2004, 05:13 PM
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#205
08/19/2004, 05:16 PM
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#206
08/19/2004, 05:19 PM
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#207
08/19/2004, 05:21 PM
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Spend some time looking up how little iron is involved. |
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#209
08/19/2004, 05:25 PM
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Randy do some time looking at U of Miami and Hawaii stuff. Also stop beating the iron to death. Look up how pH releases P from sediments. We all know you have different Ph in a sand bed that's performing denitrification/eutrophication, Right?
P is necessary for life. It's necessary for these bacteria, and you have those bacteria or you would not have denitrification. Don't matter if you have sand, coral chips, lava rocks, or marbles - all you need is anaerobic areas and no where for them to go but up. I'll check back in later to see how you guys are doing. 
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#210
08/19/2004, 05:52 PM
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You ask a reef aquarium to perform denitrification, eutrophication is a product of denitrificaton. You can't have one without the other, they are one and the same.
OK, before I try to answer that one, let me hear your definition of eutrophication. I don't want to have a great answer spoiled when you redefine it to mean "The result of denitrification". 
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Randy Holmes-Farley |
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#211
08/19/2004, 06:03 PM
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Spend some time looking up how little iron is involved.
I thought I bolded that part above??? More iron than phosphate. Since my system can handle a lot of P (based on how fast my macroalgae grows), I'd need one whopping iron mine in the sand bed. You didn't think we started our sand beds with tailings from Boomer, did you? i dose iron and use phosban.......... The amount of iron that I dose is inconsequentially small relative to P. I don't know how much iron is released when folks use the iron-based phosphate binders.
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Randy Holmes-Farley Last edited by Randy Holmes-Farley; 08/19/2004 at 06:14 PM. |
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#212
08/19/2004, 06:12 PM
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You keep trying to lead this into a sudden crash.
And if your version of old sand beds lead to a crash boils down to the simple idea that some sand beds may collect and allow degradation of organic detritus, which on decomposing can release nitrogen and phosphorus, then I'd have think that such terminology makes it sound worse than it is to many aquarists who are trying to understand. Why not just use the detritus description, instead of vague, unexplained, and possibly not relevent theories that will scare folks into thinking the problem is something quite differentt, more ominous, and not worth trying to understand?
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Randy Holmes-Farley Last edited by Randy Holmes-Farley; 08/19/2004 at 06:37 PM. |
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#213
08/19/2004, 06:34 PM
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Quote:
 We've known each other too too long.  It was back on page five. Quote:
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#214
08/19/2004, 06:36 PM
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#215
08/19/2004, 06:42 PM
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You ask a reef aquarium to perform denitrification, eutrophication is a product of denitrificaton. You can't have one without the other, they are one and the same.
IF the sand bed were the only method of nutrient export, and IF it acts as you say, then that might be true. But whether the claims about phosphate export are true or not, the water can easily be kept from being eutrophic in other ways. My water has low levels of phosphate, presumably from some combination of skimming, limewater, macroalgae, etc. So sand beds and eutrophication are not inextricibly linked in every aquarium. Further, I do not define macroalgae growth in my refugium as "proliferation"
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#216
08/19/2004, 06:43 PM
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I thought I did lay it out. You have denitrification taking place.
You have to have nitrogenous compounds in order to have denitrification. Can you add nitrogenous compounds without adding anything else? And all those anything else's just build up. Found it, back on page four. I think it would be easier to just retype it. Quote:
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#217
08/19/2004, 06:57 PM
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IF the sand bed were the only method of nutrient export, and IF it acts as you say, then that might be true.
Nope, remember diffusion. Your tank will always have first grab at it. The best you can do the way you're doing it, it after the fact. Look it up, it acts exactly the way I'm saying it does. Don't just ask me about it. Look it up and you'll see I'm right. But whether the claims about phosphate export are true or not, the water can easily be kept from being eutrophic in other ways. My water has low levels of phosphate, presumably from some combination of skimming, limewater, macroalgae, etc. What kind of P are you testing for that you know that you have low levels? What form? So sand beds and eutrophication are not inextricably linked in every aquarium. Oh course not, only in the ones that have detrius in the sand. Further, I do not define macro growth in my refugee as "proliferation" Well, if you don't light you tank bright enough, or have enough things in the tank to keep it under control, or if you just don't mind seeing it, or or You are also not trying to keep animals that are sensitive to P. |
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#218
08/19/2004, 06:59 PM
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Randy,
When using limewater were does the PO4 go. And if it's just hiding what might make it become disolved latter. Or is the same thing as the PO4 in the DSB. Steve U
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#220
08/19/2004, 07:20 PM
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Bomber,
Was the "Tell him what I would say" my answer from you? Steve U
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AKA, Riff |
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#221
08/19/2004, 08:56 PM
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Trophic States
Oligotrophic Clear waters with little organic matter or sediment and minimum biological activity. Mesotrophic Waters with more nutrients, and therefore, more biological productivity. Eutrophic Waters extremely rich in nutrients, with high biological productivity. Some species may be choked out. Hypereutrophic Murky, highly productive waters, closest to the wetland status. Many clearwater species cannot survive. Dystrophic Low in nutrients, highly colored with dissolved humic organic material. (Not necessarily a part of the natural trophic progression.) |
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#222
08/19/2004, 09:01 PM
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Quote:
http://archive.reefcentral.com/forum...hreadid=361361 |
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#223
08/19/2004, 09:16 PM
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Steve free PO4 gets bound by the calcium in Kalkwater. It then looks or a clean seed surface in order to percipatate out of solution. Usually the sand is the best first choice as LR is usually covered by algae. Once on the sand bacteria begin to reduce it in order to free the P for thier consumsion. The whole process from bind up to re-release usually takes about 12 hours in hour tanks.
Mike |
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#224
08/20/2004, 12:05 AM
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It is funny how all this stuff was the "New Wave" created by some disgruntle outcast that is now going around saying Live Rock maybe harmful to reef tanks. Boy, when are the lot of you going to open your eyes and see what's going on?
Crash = Broke, ain't working no more. Stopped producing positive results. I guess we should change the phenomenon of DSBs dying phase as the P.O.S. phase instead? Just got invited to this thread, I don't have time to post my true thoughts tonight. Boy these things can go on and on and on and some people still go around wearing blinders. |
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#225
08/20/2004, 06:43 AM
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I thought I did lay it out. You have denitrification taking place.
You have to have nitrogenous compounds in order to have denitrification. Can you add nitrogenous compounds without adding anything else? And all those anything else's just build up. Found it, back on page four. I think it would be easier to just retype it. News flash. Aerobic metabolism of organics leads to the same amount of phosphorus being released. Maybe the answer is to keep the whole tank free of oxygen atoms. Seriously, while I have always accepted the argument that detritus is not generally a good thing where ever it lands and degrades, and that may be a knock against sand, I don't see how the mode of degradation of it matters. So again, if we confine this discussion to the degradation of organics being bad, that's unlikely to develop much disagreement. It's when some folks invoke special, unspecified but scary things in the sand that it gets more contentious.
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Randy Holmes-Farley |
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Linear Mode
