About science; About seaweed

They say it is about science produced by the California Institute of Technology and originally broadcast by station KPCC in Pasadena California. The programs are made available to the station by a national educational radio. This program is about seaweed meeting to discuss this topic. Dr. Peter Liss a man and his guest Dr. Wheeler now an associate professor of Environmental Health engineering. Here now is Dr. Leslie Mann. For centuries the ocean and its mysteries has fascinated the sailor landlubber and poet one Victorian poet wrote sand strewn caverns cool and deep where the winds are all asleep where the spent lights quiver and gleam where the salt weed sways in the stream where the sea beasts range all around feed in the use of their pasture ground. Those lines are by Matthew Arnold from his work the Forsaken Memon. Today we have with

us a far from forsaken Merman Dr. Weeden North graduate of Celtic the Scripps Institute of Oceanography and professor of Environmental Health engineering at Cal Tech. As a biologist an engineer can you tell us something about those sand strewn caverns where the salt weed sways in the stream. Yes. That's seen a good deal of it myself and I can assure you that California underwater it is beautiful and fascinating as Matthew Arnold depicts it. We have underwater jungles deserts canyons mountains. Reefs. And I've never seen anything to beat it on Dr. There are some places that equal it that the fascination of the place continues to hold me after many years of looking at it I suppose really most of the world is is

underneath the oceans. Yes that's right. A little over two thirds of the world lies underneath the surface of the sea. This is something that it's about we need to know a good deal more about because there are certainly vast resources that are untapped in this watery world. The watery will is quite different from the UN that we trade on. Well there are differences and there are similarities to. The temperatures in the ocean for instance tend to be more uniform you don't. Get a tremendous fluctuation between day and night. Something that does fluctuate more than we have here on dry land is the pressure at the upper part of the sea that pressures roughly what it is here on dry land but if you go down for every 33 feet pressure increases by

one atmosphere this builds up very rapidly where why is the pressure so much more and what does it mean to beasts under the sea. Well it doesn't mean anything to a beast under the sea if if he's made entirely out of solid substance or liquid such as water because he's are incompressible But if he has air spaces in his body such as a man does why these compress as you go down to greater and greater pressures and. This can cause problems if the pressure inside and outside already equalize. You can get squeezes which divers experience and they're quite harmful. I might mention some of the other differences light intensities are always much dimmer underwater and after you get down through 400 feet there's inky blackness. It takes a lot more energy to

move underwater because the watery medium is so much more viscous. Does that mean that the Sienna mills are relatively stronger than horses or dogs. No it turns out that they move rather slowly or if they're rapid movers they're much more streamlined than land animals with the possible exception of birds. But I suppose in many ways there are similarities between these underwater environment and our very definitely especially when we get in the biological field we find many of the same basic principles. The. Plants are all important under water as they are in dry land because they capture the energy of the sun which is essentially what keeps us all going.

Photosynthesis is the process whereby plants convert light energy to chemical energy. In the chemicals of their bodies and then some animals the herbivores the plants the carnivores are meat eaters eat the herbivores so that everything ultimately depends on the plants. But on this question of like Tweedle you said it was very dark done. Oh this is right. And the plants can really live only in the uppermost layers of the sea. If they sink down to these dark areas they perish. And one reason the shore are so prolific is because the bottom of course keeps the plants from sinking. And some plants actually attach to the bottom just like plants grow in the ground here upon dry land.

And this is the importance of seaweed really because these. See we can achieve huge massive forests and form extremely rich environments in the ocean. Now people talk about sea weeds and but in California the wood is always kelp. Does that mean the same thing. No kelp is a particular kind of seaweed it's a brown one. It's generally of a calyx are huge enormous plants. And one of the important calques that we have here in Southern California giant kelp is has been called the longest plant in the world. The ones we have here only 200 feet long but they've been reported from the southern hemisphere. AS. Lankes ranging from 300 to a thousand feet is this length.

Do they grow straight upwards or do they just sort of stream out as Matthew Arnold has it. Well. When there's a strong current running they stream out. But when there's slack water. The kelp has a little gas bobs on it that boy it up and it comes straight up to the surface and spread out over the top of the sea to form a kind of a canopy this canopy is particularly important here in Southern California because we cut it away and use it. Why are your associates especially concerned with cutting away the stuff I mean does it get in the way of shipping or what is the real purpose. Oh no no it's used by man in all kinds of. Things for example. And goes into fertilizers into animal feed. But one of the most important uses is an exotic chemical that's

extracted from it called allergen. Knowledge and what exactly. That's a funny name one doesn't hear it much. What is this. Y'all probably eat now engine two or three times today without realizing it. I'll gin gets into used an ice cream when you have a little bit of algae in an ice cream like ice crystals are reduced and you don't get this rather granular ice cream. Heavens whatever sort of things do they do with it. Well it's put in salad dressing it keeps the oil in the water of the dressing mixed up in a permanent emotion. We find it in toothpaste textiles paints for printing. Firefighting pharmaceuticals. It's even put into beer where it tends to maintain the foam stable on top of the beer and makes a glass of beer look like a glass of beer.

Well I like that touch about the beer we lead but tell me what did people use to make beer or textiles or ice cream before they knew about algae and have they always used. Can you get home you know all actually allergen was discovered about 1883 by a British chemist named Sanford and it went for almost 50 years without. Having any particular use although Sanford felt that it was a most versatile chemical. But then some people down in San Diego here. Began to find all kinds of uses for it in industry and through their ingenuity and resources mental resources. We have this extremely valuable kelp harvesting industry in Southern California. About 100000 tons of Calabar harvested a year.

Is this the main place in the world where they harvest this kelp or are there other places it's collected also in giant kelp I might say grows all over the world as well as some of the other smaller kelp Scn allergen can be gotten from many of these. Allergen is manufactured in Europe and there's an allergen company or two on the East Coast of America. But. Our Southern California industry is by far the largest. It is that because you need relatively warm waters do you get the same sort of kelp and sea weed growth in the North Sea for example. You get. Well let me say first of all that we have a fairly cold waters here in Southern California because of the prevailing currents come down to us from the Gulf of Alaska. And the kid ups can do favor the colder waters of the world. You actually find a much reduced in the tropics.

The big jungles are found around the. Land masses of the Southern Hemisphere and occasionally here and there in the northern hemisphere. Actually a giant cow doesn't grow in European waters and they have to use some of the smaller ones. Are at sea but of course when we think about the traces from the sea most people think about all the various fishes and all the spiny shiny creatures which can be pulled out and which make such a delicious lunch or denies they connected with the kelp in any way. I'm glad you mentioned it because it is very very intimately connected with Calpe. And with other sea weeds. A good many of them. Eat this material directly as food. There are schools of fishes browse through kelp baje just like cows go through a pasture. And then of course as I've said

before. There are the meat eaters a carnivores that live on these herbivores and the kelp beds are truly jungles they're just teeming with life of all kinds. Other animals that we harvest from the kelp beds in addition to the fishes or the lobster and the abalone. I always thought of the lobsters living among rocks and I never thought of kelp as being among the rocks is that is that the way things are or am I just mistaken. Noah Wyle kelp and lobster both live among the rocks that kelp doesn't have a crude root like a land plant does it has what is called a home fast at the bottom man and this is just an anchoring structure. Oh I see so the kelp crew is no nutrition from the earth in the same way that we think of a plant.

That's right the kelp gets all its. It's minerals and so forth out of the sea itself and it absorbs and throughout all the tissues of the plant not just from the root. You know we're talking about absorbing things from the sea itself. People are always worried in California about the way we dispose our wastes upwards in the form of smog. And of course our crude into the ocean into the form of sewage. Does this have any effect on the life in the ocean around our shores here. Well I might say at the start that this is an extremely complex problem and one in which I am very greatly interested because the amount of sewage that we're putting out into the ocean. Increases by leaps and bounds each year. And. I'd hate to see our marvelous resources sort of disrepair and vanish in. A sea of sewage.

Does a sewage kill everything then. Now well now and then we run a great many tests of. Diluted sewage and I might say that our engineers have very cleverly designed dispersing devices that. Really mix the sewage up fairly with the sea water so it's very quickly diluted by factors of a hundred to one or up sometimes up to 500 to one. But you get these tremendous dilutions it's not toxic to anything. So so really we have this completely under control and it doesn't make any difference to anything that goes on down there. Well I wouldn't go so far as to say that because one of the things that has disturbed me and disturbed a great many people is that many of our richest kelp beds that are near these submarine outfalls discharge sewage many of these kelp beds have

disappeared in recent times and the disappearance if you look at aerial photographs taken year after year that part of it can't bad nearest the sewage discharge is the part that disappears first and then it. It leaves us at increasing distances. That's pretty good evidence that there's some relationship there. But I thought you just said that the sewage didn't affect the kelp beds. Well what we think happens in these cases. Is that the sewage upsets a rather delicate ecological balance. What does ecological mean. Well ecology has been defined as scientific natural history. I'm sure. Many of the listeners. Love to go out and make observations in nature on plants and animals. And this is a very rewarding pastime and if you make a

lifetime profession of it and. And record these observations. And accumulate them compare them with other ones and short use and methods of science why then you're an ecologist. I see so he studies the relationship of everything to everything else. Yes that's a good way of putting it because that's the way it often turns out. You have. So many things. Going on that you have. You can't just isolate one of them and study it. You know I'm fascinated by your talk about sea urchins. I always remember being brought up with pictures of street urchins. These are funny that will slum boys with tonsil hair while they see a chins do they run around street corners or Iraq. Actually I believe the word comes from the French where the street urchins were caught. And

long before anybody called the marine animals by the same name and then one day somebody compared this little spiny pin cushion from the sea to the head of St.. And everybody thought that was so appropriate that they proceeded to call a marine animal an urchin ever since. I love that touch. But it is the sea urchin really an animal or is it a plant. Or is there a distinction for that matter. Well for our purposes I think there's a clear distinction. Sometimes when you get down to the microscopic level you have difficulties. In answer to your other question the urchin is very definitely an animal. And it's a rather voracious animal it eats plant material and it's a very wasteful eater. It doesn't ever get up off the bottom very far.

It doesn't have any limbs or hands to hole on left so it just grazes around the bottom of these kelp plants takes a few bites and the anchorage is lost in the main part of the plant maybe two hundred feet long drifts away and is lost to all the other animals. But now when this plant drifts away. In other words when you cut the bottom off of this plant does that mean that it's going to die. It probably can survive in the drifting state for a few months but sooner or later it gets carried into the tropics. And as I've said it can't withstand warm temperatures so it dies. Talking about the tropics I'd like to make a little excursion. What about the Sargasso Sea that we always read about in romantic novels. This is a sort of a gigantic sitting off the West Indies in the Atlantic Ocean and

the currents just go. In a circular path. Round and round apparently one of the drifting sea weeds has gotten in there and flourished. This particular seaweed is called a saga some lead giving the name Sargasso Sea to the area. I see that normally of course that seaweed is not rooted on the bottom in any way the ocean must be terribly deep in those regions. That's right it's not rooted it can it can withstand the warm water so it just flourishes there. It's a matter of fact there is a similar circular movement goes around the South Pole. I should say the Antarctic continent. It doesn't happen in the at the northern end of the planet because the land mass is in the way but this west wind drift its call goes around the

South Pole and Makar of these giant kelp plants. Macro sesterces is its name. Apparently go around endlessly there and they seem to survive. People of color the Macra Cistus see in comparison to the Sargasso Sea. I guess that well you know I think I'd like to get back to these TA's little head little referee and the actions that seem to have these very bad and messy eating habits they spin everything and they just take a bite of one or two things and then they'd leave it how I mean how are we going to get rid of these. They must be a serious menace to the kelp beds. Well. Ordinarily Nature takes care of the urchins because after they've gotten rid of all the callup and all the other animals star the urchins either have to move away and find greener pastures or they starve to death and selves. Once the urchins are gone why then the vegetation comes back.

And with it all the richness of the associated animal life in the ocean. You talk about these chins moving away but they don't just simply take a bus or they have no feet. How do they move away while they have these spines that stick out all over them make them look like a pain question and they have little flashy like. Protuberances little arms or tubes that stick out and they have suckers on the end that they can grasp the bottom with and they can actually move along at a rate of three or four feet an hour. And presumably they cover a matter of a few thousand feet or a thousand feet or so and a year capable of doing this. How do they in a rock what way to go. Well if they're being

guided by the odor of sea weeds somewhere else. This tends to move them off in that direction if there's seaweeds up current from them and in fact we've detected this and some experiments we've gone into these areas where urchins are completely dominant and we've anchored seaweeds up off the bottom so that they can't. Get at them they're just two or three feet off the bottom and the urchins come congregating in under them. So we know that they can detect these plants. Good heavens. So now we discover that under the ocean we have these great beds of kelp that are almost like wheat or something that you might have on land and that we have trimmings which are somewhat like the pests the plague from is you'll be suggesting that we're actually farming under the ocean soon.

While I think we are because we found ways to control the urchins we. Use a. Toxic but cheap chemical called quicklime that comes in a lamp form and we go out and sprinkle it on the water and it drops down to where it hits an urchin it kills him. And when you've gotten rid of the urchins why you can bring the kelp back much quicker than it would if you had to wait for the urchins to starve to death. Does this have any effect on any of the other creatures living underneath there. Well. For the most part no if you control your dosage properly the urchins appear to be much more sensitive than other animals so that if you just sprinkle air quicklime very lightly you can clean out the air and not harm anything else. You know we die we introduced you as the Forsaken Merman but I suppose you do most of your work at a desk and with mathematics and great serious

tomes rather than really going out there and seeing what's happening. Well I do a considerable amount of work at my desk Yes the day I get out into the ocean usually at least once a week and sometimes three or four times. Are you actually going to go diving underneath the ocean then do yo yo. And. Right now we're trying to transplant some kelp barren area down off a lawyer. I see you. You wear the normal skin diving equipment is this a dangerous occupation. Well it's sort of like driving an automobile or handling a loaded gun. If you do it improperly you can be a hazard to yourself and others. But if you do it properly you can accomplish a great deal. Have a good deal of fun. And and it really isn't hazardous when done properly.

Have you ever had any experiences with any of these monsters of the deep during your trips under the ocean. Well I had a shark once come in and look me over. And the important thing when a shark is looking you over is to look him over because if you turn and swim away in an awful flap why be right on your fins nibbling at them. It's like if you run away from from an angry dog he'll chase you. But if you stand your ground and show him that you're not afraid you stand a much better chance. I see. How deep do you go when you when you go how deep can people go comfortably and skin diving. Well with the ordinary apparatus it's available. Here. We can go down 200 feet but really you can't do much more work. Comfortably than down a

hundred feet at the present time. This I might say is. If you're thinking of using the resources of the sea working down to 100 feet all around the world gives an area the size of the continent of Africa to develop. Well that is a really fascinating picture of two thirds of the world. We have kelp. We have it since we have sea beasts and we have men working down there in relative comfort 100 feet below the surface of the ocean. Thank you very much Rita. Most interesting. This was about science with host Dr. Peter listen and his guest Dr. Wheeler nor an associate professor of Environmental Health engineering joining us again for our next program on another subject of interest to scientist and layman will be discussed.

About science is produced by the California Institute of Technology and is originally broadcast by station PPC Pasadena California. The programs are made available to this station by national educational radio. They say is the national educational radio network.