湘中丘陵区马尾松林粗木质残体研究

Coarse woody debris in a Pinus massoniana forest in the hilly area of Central Hunan Province

以湘中丘陵区马尾松林为研究对象,分析粗木质残体（CWD）的储量特征、物种组成、径级结构以及腐烂等级,研究湘中丘陵区马尾松林CWD的基本特征。结果表明：湘中丘陵区马尾松林CWD的平均储量为1.72 t/hm2,马尾松和杉木是针叶CWD的主要组成树种,樟树、南酸枣、枫香是阔叶CWD的主要组成树种。马尾松-阔叶树种混交林的CWD总储量显著大于马尾松-杉木混交林的,两者的CWD总储量与其对应森林总生物量的比例差异明显,且均表现为随森林生物量增长而增加的趋势。CWD的个体数量随着径级的增加而减少,呈反J型下降趋势,且不同存在形式CWD的数量比例大致表现为倒木〉枯立木〉大枝〉根桩。CWD具备完整的腐烂等级（Ⅰ~Ⅴ级）,主要集中在Ⅰ、Ⅱ腐烂等级,且随着径级的增加,各腐烂等级CWD的数量比例呈现逐渐减少的趋势。

The characteristics of storage, species composition, DBH class and decay class of coarse woody debris（ CWD） were studied in a Pinus massoniana forest in the hilly area,Central Hunan Province. The results showed the average storage of CWD was 1. 72 t / hm2,the conifer tree specie of CWD were Pinus massonianaand Cunninghamia lanceolata,the broad-leaved tree specie of CWD were Cinnamomum camphora、 Choerospondias axillarisand Chinese sweet gum. The storage of the area of mixed of P. massonianaand broad-leaved tree species significantlly bigger than the area of mixed of P. massonianaand C. lanceolata,showed with the increase of forest biomass has a growth trend. The density of CWDs decreased as increase of DBH class,and followed the inverse J-shape,the ratio showed log 〉snag 〉branch 〉stump. The CWD had all classes（ class I to V） with a focus of decay classⅠandⅡ,the decay class of CWDs decreased with increase of DBH class.