When provided with continuous nourishment, trees, like people, grow “complacent”—the word tree-ring scientists use to describe trees like those on the floor of the Colorado River Valley, whose roots tap into thick reservoirs of moist soil. Complacent trees aren’t much use for learning about climate history, because they pack on wide new rings of wood even in dry years. To find trees that feel the same climatic pulses as the river, trees whose rings widen and narrow from year to year with the river itself, scientists have to climb up the steep, rocky slopes above the valley and look for gnarled, ugly trees, the kind that loggers ignore. For some reason such “sensitive” trees seem to live longer than the complacent ones. “Maybe you can get too much of a good thing,” says Dave Meko, a tree-ring scientist who has been studying the climate history of the western United States for decades. Tree-ring fieldwork is hardly expensive, but during the relatively wet 1980s and early ’90s, Meko found it difficult to raise even the modest funds for his work. “You don’t generate interest to study drought unless you’re in a drought,” he says.
【題組】49 According to this passage, when are people most likely interested in the study of drought?
(A)In times of war.
(B)After an earthquake.
(C)Right in the midst of water shortage.
(D)At the time when both trees and people grow complacent.
44 With the coming of the election, both of the candidates will need to _____ their support in order to win.
(A) consolidate (B) contribute (C) deprive (D) deceive
23 Because of the heavy rainfall today, all public ______will only be running on major thoroughfares.
(A) penalty (B) journeys (C) varieties (D) transit
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