栽杉留阔模式的杉木生长过程特点

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The growth process of Chinese fir trees under the pattern of reserving broad leaved tree species in Chinese fir plantation and in pure Chinese fir stand(control) were studied. The results showed that comparing with the control, the tree height, D.B.H and tree volume increment of Chinese fir under the pattern was a little slower in the early seven years and higher at 8~22 5 year old. After 22 5 year old the increment declined hardly (though total increment was higher than the control). All these reflected the effect of tree competition and soil fertility development on the tree growth of Chinese fir. In order to cultivate large timber under the pattern, the relationship of Chinese fir and broad leaved tree species must be adjusted in time and the broad leaved trees existed in the same forest canopy with Chinese fir must be cut over at about 20 year old. The growth process of Chinese fir trees under the pattern of reserving broad leaved tree species in Chinese fir plantation and in pure Chinese fir stand (control) were studied. The results showed that comparing with the control, the tree height, DBH and tree volume increment of Chinese fir under the pattern was a little slower in the early seven years and higher at 8 ~ 22 5 year old. After 22 5 year old the increment declined hardly (though total increment was higher than the control). All these reflected the effect of tree competition and soil fertility development on the tree growth of Chinese fir. In order to cultivate large timber under the pattern, the relationship of Chinese fir and broad leaved tree species must be adjusted in time and the broad leaved trees existed in the same forest canopy with Chinese fir must be cut over at about 20 year old.
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