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在我国亚热带、暖温带靠近人口密度较大的市、镇附近的低山丘陵地区,常分布着一定面积的人工或半人工经营的针叶树纯林.如在亚热带常绿阔叶林区中的东部亚区有马尾松林,西部亚区有云南松林、华山松林;在暖温带区中有侧柏林、赤松林、油松林、白皮松林以及由国外引种栽培形成的黑松林、湿地松林、火炬松林等.由上述各种针叶树所形成的各种针叶林群落结构和林地的基本情况是;(1)树种单一;(2)林龄相似;(3)树干细长,修枝较高,树冠较小;(4)下木层及枯枝落叶层缺乏;(5)乔木层林冠稀硫,郁闭度低,透光量大,林地干燥导致林木生长缓慢,甚至形成“小老树”;(6)针叶树纯
In China’s subtropical and warm temperate zone near the densely populated cities and towns in the hilly areas near the town, often distributed in a certain area of artificial or semi-artificial conifer pure forest .As in the subtropical evergreen broad-leaved forest in eastern Pinus massoniana forest in the sub-region, Pinus yunnanensis forest and Huashan pine forest in the western subregion. In the warm temperate zone, there are Platycladus orientalis, Pinus koraiensis, Pinus tabulaeformis and Pinus bungeana, as well as black pine forest, Pinus elliottii forest and Pinus taeda forest introduced from abroad. The basic conformations of various coniferous forest communities and woodlands formed by the above coniferous trees are: (1) single tree species; (2) similar forest age; (3) slender tree trunks, higher pruning and smaller crown ; (4) Lack of understory and litter layers; (5) Canopy of dilute sulfur in forest canopy, low canopy density and large amount of light transmissibility; dry woodland leads to slow growth of forest trees and even “small old trees”; Conifer pure