Showing posts with label Ecology. Show all posts
Showing posts with label Ecology. Show all posts

Monday, June 7, 2010

Gulf Oil Spill

In Die Welt,  a German newspaper there was a story about a new variety of concrete which is seeded with microorganisms that will actually remove organic waste from water.  Time to place an order?

  Below is my (very rough) translation of the piece linked to above:


It stinks like rotten cheese, and besides Japan, the Germans first cultivated Natto during the Second World War, on their submarines.  Natto is a slimy mixture of fermented soybeans that the Japanese for centuries have polished off for breakfast.  With the help of the hungry but resistant Natto bacteria, Japanese reseachers have now developed a concrete which sustainably converts smelly sewers and stinking streams into clear water.

Foto: Marubeni/Kölling Beton aus Japan verwandelt stinkende Flüsse in klare Gewässer
The firm Koyoh has now employed this development in Yanagawa, a city with a dead, black, stinking creek. Now in just two weeks the bacteria saturated concrete disapateed the smell and in two months the water was again clear and good enough for carp. This piece of technology was produced by nature over the ages, and through cultivation yields high capacity bacteria which can consume or even produce oil.  However, the Natto-bacteria have long served as a living water filter. Fish farmers and aquarium owners shake them in as a powder to reduce turbidity.

The new discovery of the researchers from Koyoh consists of this, the Natto-bacteria can be processed with a variety fo concrete, which for years, if not decades has served as a breeding site.   No one will need to sprinkle the Natto powder.

"A method which also works in flowing water," according to Sachiko Kobayashi, the manager of the petrochemical division of Japan's second largest trading company, Marubeni whose duties include the international operations.
The capability of nature through the bacterialy charged concrete to assist in the repurification of a source, should not be underrated.  Almost all attempts failed, since most bacteria lose their appetite in the alkaline environment of concrete.  In the Koyoh patent application, the bacteria of the eco-cement, that is Bacillus subtilis (Hay bacteria), Bacillus thuringiensis, and bacillus sphaeris, survive both the alkaline conditions and heat very well.  Thus they are well suited to working into concrete.
 For a label for the bacterial water filter the Japanese reached deep into Greek mythology: Gaia Healing Project, appears in the sales catalog, named for the goddess Gaia, who in antiquity embodied the earth.
 The bacterialy infused concrete is marketed by Marubeni as "EcoBio-Block" in diverse porous large grained concrete forms, cylindrical for aquariums and fishtanks, stonelike for lakes and water tanks, or as rippled tiles for canals and streams.

It works this way: on contact with water, the hungry bacteria search out food.  In doing so, the ferment organic matter, and convert ammonia into nitrite and then nitrate.  This nitrification is an important part of the purification of water.  And even better, a shortage of nitrate is an environmental risk.  The unicellular creatures are nearly indestructible, surviving both freezing and boiling water.  If the water tempurature is below 10 degrees Celsius, they become inactive. 
In application, certain conditions must be observed, that not too much mud or leaves cover the tiles , says Kobayashi.  The bacteria require oxygen.  In light of the water pollution in Russia, and also in Asia's ecologically challenged developing countries, Marubeni expects good business.  In standing water, Kobayashi the manager recommends putting three blocks per cubic meter of water.  In canals or streams, once piece of Natto-concrete every ten meters.

Wednesday, August 5, 2009

Ecology and Rhetoric

This post deals with two things that I have absolutely no professional training in. I also haven't surveyed the literature to determine whether this is novel, but I suspect in might be. Why, because of what C.P. Snow called the Two Cultures. These are roughly speaking the sciences and the humanities. I therefore believe that no one has likely considered the relationship between ecology and rhetoric, but I would be happy to be corrected.

The term which I find particularly interesting from a rhetorical point of view is "invasive species." Here's what Wikipedia has to say about them. What interests me about the term in the value set that it appears to incorporate. Specifically, most of us are likely to have the notion that an invasion is a bad thing. (I except certain former officials of the Bush Administration.) Consequently, our knee-jerk reaction to hearing the an invasive species has established itself in a particular locality is probably negative.

Now current theories of speciation, suggest that geographic and/ or reproductive isolation are necessary for a new species to emerge. The late Stephen J. Gould suggested, in fact, that speciation might occur through a process of punctuated equilibrium. What does this mean for ecology? Unless a species never leaves the biome where it evolved by whatever mechanism, it must be invasive at some point. If a newly emerged species is fitter in an evolutionary sense than the parent species, or the species that fill the same niche elsewhere it will spread at the expense of those species.

Now, living in the South, I am well aware of the toll that kudzu lays upon native species. However, the problem with such introductions is not the species itself, but the absence of the controls that have evolved in its native biome.

In the sense that the term is often used, humanity could be considered an invasive species everywhere in the world except for Africa south and east of the great rift system. Now perhaps invasive species carries exactly the appropriate connotation needed for ecology. However, I really think a more appropriate term is "exotic species."