[Coral-List] induced mineral accretion
dr_iamacdonald at yahoo.co.uk
Wed Jul 25 06:50:07 EDT 2007
Dear Toms, Biorock users and other interested parties
After reading the recent posts and an article in Nature that in the US they are now paying $$$$ to remove old tyres (due to their instability and some might argue toxicity) thrown into the sea as artificial reefs I would like to know about the long term viability of this Biorock method. For the Colombian Tom I also offer some advice regarding power companies.
I don't mean to detract from the novel / innovative and resourcefulness of this technology but for the last 4 years I have lead a split life following the coral reef related discussions but also getting heavily into chlorination of seawater - whats the relevance to BIOROCK you ask? Well we have electrochlorinators to produce sodium hypochlorite - "chlorine" same as that you use to disinfect drinking water or your local swimming pool. We abbreviate these machines to ECP. Most coastal power stations will use seawater for cooling purposes and will also use this technology and be aware of the properties I mention below. So for the Colombian Tom any power station managers you approach will easily understand the basics of the Biorock method. They may also hold some of the concerns below.
On the components of these ECPs (Cathodes and Anodes) we regularly get a build up of "scale" that is removed by acid washing since they reduce the efficiency of chlorine production that would probably eventually cease altogether. Now my understanding is that Biorock also uses cathodes/anodes and is basically the same technology used with a different intention.
So my question is the "technique" of biorock any different? In other words will the scale build up will eventually cease and the associated microlayer of a "protective" halo around such structures provided by the sodium hypochlorite and other more potent chlorination by-products. This leads to an effective stopping of any precipitation of carbonate around the metal bars. Thus after a year or two (longer???) there is no point in providing these structures with a power supply and they just become structures providing vertical relief much like other human made reef modules with the benefit of not being coal-ash / plastic / rubber / concrete-based. In the long term the metal will surely rust such at that exposed to water in concrete reinforced structures of buildings etc. expand and damage the integrity of anything attached to it?
Another question is the improved ability of corals to survive bleaching and their enhanced growth rates on BioRock. Could this be due to the chlorine keeping the local bacterial (and other microorganisms) population low? Also keeps away preditors/competitors/etc. I have been lead to believe that the corals bacteria community play an intricate role in bleaching that we are only just starting to understand. But please dont go pouring Chlorox all over the bleaching reefs
I dont know if you have observed this with Biorock but there are reports (paper I would need to find
..) of certain fish species having a tendency to swim into chlorinated water plumes and they have proposed that this is due to the high the fish received from CBPs. They can appear quite docile and unresponsive but then perhaps they are just teenagers?
A lot of countries are signatories (but not Colombia) to the London Convention (1972) and London Protocol (2005) to prevent the dumping of waste at sea which some may now consider the example of the tyres being a prime candidate especially if not fully engineered deployment. Small scale metal projects such as Biorock may not make the reverse list that allows certain materials to be dumped. Permits etc. would be needed.
Finally, I have heard that there is a plan for a Biorock-type reef being installed off Dubai perhaps one of the islands - has anybody heard anything about this
Sanderson, K. (2007) Divers dismantle artificial reef: Wayward tyres were damaging corals off Florida . Nature. doi:10.1038/news070709-3.
Aleksandrov B.G. et al. (2002) Ecological Aspects of Artificial Reef Construction Using Scrap Tires. Russian Journal of Marine Biology 28 (2): 120-126.
tom lop <tolope at gmail.com> wrote: Dear coral-listers,
Thanks to all of you who answer my request some days ago about artificial
reef accretion by electrodeposition technique. I will try to keep in mind
all of your recommendations and suggestions.
After the different opinions about this technology, I think I should clarify
some of the reasons that took me to try this methodology here in Colombia,
if support results of course.
Here in Colombia, founds destined for marine investigation and mechanisms to
conserve and regenerate marine ecosystems, as coral reefs, are sometimes
scarce or difficult to access. Having this in mind and the aim as Marine
Biologist to study, protect and regenerate marine ecosystems, I propose this
project to an electrical energy commerce company hoping that they support at
least part of the project. What I´m trying with this idea is to hopefully
involve a company who works with electrical energy (as the main part of the
electrodeposition technique) to protect and regenerate actually one of the
most damaged marine ecosystems, bringing benefits to local communities.
After all your valuable comments and the estimated costs of the project, I
understand that it´s not a cheap technique and that it could be
unpredictable. Even though, having into count that it could be involved the
local community, coral reefs and an electrical energy commerce company, with
feasible benefits to all of the parts (tourism and fishing for community,
and credits because of environmental restoration and protection for the
company), I would like to make an attempt
Again, thank you so much and sorry for the multiple mistakes that should be
in the message (I know that there should more than one), I try to do my
Tomás López Londoño
Universidad de Bogotá Jorge Tadeo Lozano
Coral-List mailing list
Coral-List at coral.aoml.noaa.gov
Do not compromise. Get unlimited storage and first rate spam protection with Yahoo! Mail.
More information about the Coral-List