Long-term effects of nutrient and CO2 enrichment on the temperate coral Astrangia poculata (Ellis and Solander, 1786)

Long-term effects of nutrient and CO2 enrichment on the temperate coral Astrangia poculata (Ellis and Solander, 1786)

JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY, APRIL 2010

DOI: 10.1016/j.jembe.2010.02.007

PDF Available

Nutrient limited corals are unable to utilize an increase in dissolved inorganic carbon (DIC) as nutrients are already limiting growth, thus the effect of elevated CO2 on saturation state drives the calcification response. Under nutrient replete conditions, corals may have the ability to utilize more DIC, thus the calcification response to CO2 becomes the product of a negative effect on saturation state and a positive effect on gross carbon fixation, depending upon which dominates, the calcification response can be either positive or negative.

Biological control of aragonite formation in stony corals

Biological control of aragonite formation in stony corals

Stanislas Von Euw1, Qihong Zhang, Viacheslav Manichev, Nagarajan Murali, Juliane Gross, Leonard C. Feldman, Torgny Gustafsson, Carol Flach, Richard Mendelsohn, Paul G. Falkowski

Science  02 Jun 2017:
Vol. 356, Issue 6341, pp. 933-938
DOI: 10.1126/science.aam6371

PDF Available

[…]mineral precipitation in corals is a biologically controlled process mediated by organic molecules, rather than an abiotic one that depends only on physico-chemical conditions.

[…]biomineralization in stony corals is not simply related to physicochemical parameters such as the equilibrium saturation state of carbonate ions or the bulk pH of seawater (33).

Effects of herbivory, nutrient levels, and introduced algae on the distribution and abundance of the invasive macroalga Dictyosphaeria cavernosa in Kaneohe Bay, Hawaii

Effects of herbivory, nutrient levels, and introduced algae on the distribution and abundance of the invasive macroalga Dictyosphaeria cavernosa in Kaneohe Bay, Hawaii

Coral Reefs (2001) 19: 343-357

DOI 10.1007/s003380000123

PDF available.

Bubble algae!  The less-fun variant in the Family.  (Valonia is not so bad.)

Don’t provide foods to your herbivores that are more desirable.   Pellet food was the “worst”….mysis were better and more herbivores ate bubble algae when that was the tank’s food.

Aerosol dispersal of the fish pathogen, Amyloodinium ocellatum

Aerosol dispersal of the fish pathogen, Amyloodinium ocellatum

Aquaculture, Volume 257, Issues 1–4, 30 June 2006, Pages 118-123

Ashley Roberts-Thomson, Andrew Barnes, D. Stewart Fielder, Robert J.G. Lester, Robert D. Adlard

PDF Available

 

They performed three sets of tests to see how “suseceptible” a tank or pond could be when placed “close” to infected tanks:

  • The first set was more or less a typical indoor home aquarium setup.
  • The second set was an indoor setup, but force-aerosolized the infected water.
  • The third set was more typical of a pond system and simulated outdoor windy conditions and also force-aerosolized the infected water.

This is a table I prepared to show the organization of their trials into three sets of experiments:

velvet table.png

The goal of their experiments was to prove whether Amyloodinium can “ride” a water droplet to a foreign body of water and arrive intact enough to infect fish.

They did this successfully, and indeed Amyloodinium can “ride” water droplets.  But that might not be the most interesting part to us in the reefing community.

Here are some charts I made which depict the reported results for the three sets of experiments:

velvet charts.png

The first thing that jumps out at me – from the first chart – is that airstones running in an open tank like a stereotypical home setup are totally unable to spread dinospores.

As it turns out, dinospores are relatively big and subject to hypersalinity and dehydration while in transit.   It took a lot more than bubbles in a fish tank to achieve transmission – they need a lot of help to get anywhere successfully!

annual_descriptive_catalogue_-_seeds_28189729_282055573274129

The second and third chart demonstrate the successful conditions.

Without strong wind, dinospores were only infective out to a maximum of 17 inches from the source tank.

Forced-arosolization was implemented in these two experiments by spraying 2 liters of dinospore-infected water into the air through a hand-pumped sprayer somewhat like the one depicted to the left, fitted with a misting nozzle.

The Ecological Role of Water-Column Microbes in the Sea

The Ecological Role of Water-Column Microbes in the Sea
Marine Ecology Progress Series, January 1983
DOI: 10.3354/meps010257

PDF Available

 

This article gives some insight into the ecology we are missing when we try to control algae blooms with carbon dosing.

It’s not even close to a simple bacteria vs algae contest, or bacteria-to-skimmer export that gets reported in hobby literature.

A few quotes:

There is evidence that bacteria show kinesis [movement] in a field 10 to 100 µm from algal cells, close enough to take advantage of DOM (Azam, in press). Under laboratory conditions in natural sea- water, bacteria were observed to remain at distances of the order of 10 pm from algal cells, possibly being repelled by antibiotics produced by healthy algae. They attach mainly to moribund algae.

[…]it follows that the supply of either carbon for energy, or other nutrients may limit bacterial growth.  However, in phytoplankton blooms DOM is often produced, and bacteria with their large surface:volume ratio are adapted to scavenging nutrients from the water at very low concentrations.  The difficulties experienced in quantifying the release of DOM by algae are almost certainly due to its rapid uptake by bacteria.  The same argument applies to nutrient cycling.  If bacteria are so well adapted to
scavenging DOM and nutrients at low concentrations, what limits their population size to the biomass levels given in Table I ? Fenchel (1982a,b, c, d, in press) has shown that heterotrophic microflagellates in the size range 3 to 10 pm are effective bacteriovores in the sea, capable of filtering 12 to 67 % of the water column per day (see also Sorokin, 1979; Sieburth, 1982).These are principally choanoflagellates and colourless chry- somonads[…]

 

Total replacement of fish oil by soybean or linseed oil with a return to fish oil in Turbot

Total replacement of fish oil by soybean or linseed oil with a return to fish oil in turbot (Psetta maxima): 1. Growth performance, flesh fatty acid profile, and lipid metabolism
Original research article
Aquaculture, Volume 217, Issues 1–4, 17 March 2003, Pages 465-482
C Regost, J Arzel, J Robin, G Rosenlund, S.J Kaushik
https://doi.org/10.1016/S0044-8486(02)00259-4
PDF Available

Total replacement of fish oil by soybean or linseed oil with a return to fish oil in Turbot (Psetta maxima): 2. Flesh quality properties
Original research article
Aquaculture, Volume 220, Issues 1–4, 14 April 2003, Pages 737-747
C. Regost, J. Arzel, M. Cardinal, G. Rosenlund, S.J. Kaushik
https://doi.org/10.1016/S0044-8486(02)00655-5

In summary, it’s possible to replace at least some of a marine fish’s diet with high quality, specifically selected vegetable oils, but it’s not a perfect replacement in every way.

For example, growth seems unaffected, but flavor, odor and other important factors are affected.

Some, but not all, affected factors can be reformed by a “finishing diet” consisting of normal food containing fish oil.