LIVING NEAR VOLCANOES

Evening Star, Issue 22458, 1 October 1936, Page 9

LIVING NEAR VOLCANOES

Why does civilisation in _ active volcanic regions insist on getting as close to smoking fire mountains as possible and why are towns destroyed by larva and asn, frequently rebuilt directly over the ruins? The answers to these questions and half a hundred more equally as baffling have been sought by Dr E. G. Zies, volcanologist of the Carnegie Institution of Washington, who has headed expeditions into Central America and the Netherlands East Indies to study recently active craters. “ People are so impressed with the terrifying and devastating effects of volcanoes they overlook the benefits arising from them,” Dr Zies declared in a recent public address. Everywhere he went ho found inhabitants of volcanic areas turning such activities to their own benefit. “ They know they have more to gain than lose from volcanoes.” he said, “ and the chances of destruction are small, usually with ample warning.” Dr Zies carried a small portable laboratory with him in his _ travels, largely for the testing of soils. He found the luxuriant vegetation characteristic of the Hawaiian Islands, Java, and the plains and mountain slopes of Central America to be the result of unusually fertile soil. “ Mankind in the early search for food found these _ places satisfied wants,” said Dr Zies. “ Men soon learned that the destructive volcanic eruptions came only at infrequent intervals, and, even though _ distressing, only involved local destruction of crops. “ They also learned that tnese peaks towering into the sky and reaching into the cooler strata of the atmosphere were capable of of bearing food crops on their slopes which could not be raised in the lowlands.” The peaks attain an altitude of 10,000 ft or more in many lands, and are exposed to the water-bearing trade winds and monsoons. Therefore being in the tropics or sub-tropics they have & wide range of climatic conditions varying from the hot and humid lowlands to elevated areas subject to occasional frost. Such volcanic regions have supported a relatively large population from the to time, and detailed study of the archaeological and written records is likely to throw light on how these people of Central America attained a considerable culture during the so-called “ Dark Ages ” of our civilisation. ERUPTION BENEFITS.

Five of Guatemala’s peaks have been more or less active during the past 100 years. Manifestations appear as dust clouds and as flows of pumice. The erauption of Fuego in 1932, for example, took place during the dry season and covered the slopes ot the volcano with coarse ash to a depth of lOin. Much vegetation was apparently destroyed, but Dr Zies noticed, three weeks afterwards, that such vegetation as had escaped complete destruction, was vigorously putting forth foliage. When the layer of coarse ash was removed it was found that the ground was obviously moist, a condition not usual for the dry season. The Indian soon learned that corn planted in the soil below this ash sprouted promptly and grew vigorously. It has frequently been observed by the coffee planters in both Java and Salvador that their crops are larger the year after an eruption than before and this the Carnegie volcanologist believes is due to the mulching effect of the ash which conserves the moisture in the ground during the dry season. In the immediate vicinity of an active volcano the destructive action of the hot flows can be serious indeed, but farther away the new material becomes a distinct addition to the soil and has a rejuvenating effect. The fine dust which is often carried to great distances by the W'inds is of distinct value in these regions, furnishing potential soil which is made quickly available for plant growth by its porosity and fine-