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大兴安岭林区位于我国最北部,地处高寒林区,年平均气温低、干旱、风大,春季防火期长,往往容易发生特大森林火灾。该林区主要以寒温带针叶林为主,树种种类少,大都属于阳性树种,加上气候寒冷,森林结构稀疏,林分郁闭度在0.4—0.6居多,因此,林下阳光充足,生长大量的阳性杂草,增加了森林的易燃性;土层薄(一般山区土层厚度仅20cm左右),气候恶劣,林木生长缓慢。如兴安落叶松人工林达到郁闭至少需要20年。所以,有许多人认为在大兴安岭开展生
Daxinganling Forest is located in the northernmost part of China, is located in the high cold forest area, the annual average temperature is low, drought, windy, long spring fire, often prone to super-large forest fires. The forest is dominated by frigid temperate coniferous forest, with fewer tree species, mostly belonging to the positive tree species. With cold climate and sparse forest structure, the forest canopy density is mostly 0.4-0.6. Therefore, there is sufficient sunshine and growth in the forest A large number of positive weeds, increased the flammability of the forest; thin soil (usually mountainous soil thickness of only about 20cm), bad weather, slow forest growth. Such as Larix gmelinii plantation canopy closed at least 20 years. Therefore, many people think that they will be students in Daxinganling