哀牢山中山湿性常绿阔叶林枯立木数量及分配规律

Quantity and Distribution of Standing Dead Trees in Montane Moist Evergreen Broad-leaved Forest in Ailao Mountain,Yunnan

以三棵树、锅底塘、山门口和簸箕坝4块样地调查资料为基础,研究了云南哀牢山国家级自然保护区内中山湿性常绿阔叶林枯立木的数量组成、分配格局和生物量特征。结果表明:哀牢山中山湿性常绿阔叶林内枯立木的密度为(68.5±18.0)株/hm2,枯立木占全部乔木的(5.7±0.6)%。枯立木胸径(DBH)分配以小径级为主(5≤DBH<20cm),此径级的枯立木显著高于另外2个级别(20≤DBH<40cm和DBH≥40cm,P<0.05)。哀牢山中山湿性常绿阔叶林枯立木的物种组成极其丰富,分属于14科32种,树种组成以壳斗科的腾冲栲(Castanopsis wat-tii)、硬壳柯(Lithocarpus hancei)和木果柯(Lithocarpus xylocarpus),越桔科的云南越桔(Vaccinium duclouxii),杜鹃花科的珍珠花(Lyonia ovalifolia)和薄叶杜鹃(Rhododendron leptothrium)为主。哀牢山中山湿性常绿阔叶林枯立木贮量较高为(3.9±0.7)t.hm-2,生物量的树种分配以腾冲栲(Castanopsis wattii)和木果柯(Lithocarpus xylocarpus)为主。

An experiment was conducted to study the quantity ratio, spatial distribution, species composition and biomass charac-teristics of standing dead trees in montane moist evergreen broad-leaved forest in Ailao Mountain, Yunnan Province, based on data of four sampling plots. Results showed that the density of standing dead trees was （68.5±18.0） stems/hm^2, ac- counting for （5.7±0.6）% of all trees in the plots. The standing dead trees distributed mainly in small size class （5cm≤DBn〈20cm） , which was significantly more than the other classes （20 cm≤DBH 〈40cm and DBH≥40cm）. The standing dead trees of Castanopsis wattii, Lithocarpus hancei, Lithocarpus xylocarpus, Vacciniura duclouxii, Lyonia ovalifolia and Rhododendron leptothrium were abundant, belonging to 14 families and 32 species. The storage of standing dead trees was （3.9±0.7）t/hm^2. The biomass of standing dead trees of C.watttii and L. xyloearpus made up a high proportion.