北京西山国家森林公园人工林质量及景观效益分析

Analysis of the Plantation Quality of Xiahan National Forest Park,Beijing

北京西山森林公园，距市区近、交通方便、森林类型及人文古迹多，主要人工林类型１３种。幼中林多，近成熟林少；高、中、低郁闭度林分都有。不同林分物种多样性差别不明显。树种观赏指数依次为：黄护、元宝枫（２１分）＞白皮松（１９分）＞樟子松、华山松、山杏、桃（１８分）＞油松（１７分）＞刺槐、栾树（１６）＞侧柏（１５分）＞栎类（１４分）＞白蜡（１０分）．森林类型中，观赏价值高的林分面积小，有的空间分布欠合理；有的下层灌木多不便游憩；景观补救方法是：引入新“斑块”，扩大珍贵景观斑块，人工抚育、修枝等，创造适应游憩的环境。

Located at the northwest suburban of Beijing,Xishan National Forest Parkdistinguishes itself by its short distance from the urban area,convenient traffic,and numerousplantation types and ancient artificial relics. In the park more than 13 types of plantations aredistributed,which are dominated by the young and the middle-aged stands,No apparent dif-ferences of species diversities among plantations are found.The order(from high to low)ofesthetics of main tree species is:Aronsheard(Cotinus coggygnia)and Purpleblow Maple(Acet truncatum)>Lacebark Pine(Pinus bungeana)>Scotch Pine(Pinus sylvestris var lnongolica),Armand Pine(Pinus arandi),David Peach(Prunus davidiana)and Apricot(Prunusarmeniaca )>Chinese Pine(Pinus tabulaeformis)>Black Locust(Robinia pseudoaeacio)andPanicled Goldraintree(Koelreuteria panicuiata)> Orintal Arborvitae(Platycladusoeiwnralis)>Oriental Oak(Quercus variabilis) > Chinese Ash(Fraxinus chinesis ).Thetourist function of some plantations is limited at some extent by their little areas,unrationalspacial distribution and inconvenience of rest caused by understory shrubs,which can be im-proved by constructing patches of new tree species,increasing the percentage of patches oftree species with high esthetics indexes and reconstructing old plantations by pruning,tend-ing and shrub-cutting.