闽北毛竹林枯落物层持水功能研究

以杉木林和常绿阔叶林为对照,对闽北典型毛竹林(杉竹混交林、毛竹纯林、竹阔混交林)林下枯落物储量、持水特性及其对降雨的拦蓄能力进行研究,结果表明:(1)各林分未分解层、半分解层和已分解层枯落物储量、最大持水量和有效拦蓄差异较大,但均以半分解层最高,分解层次之,未分解层最小;杉木纯林枯落物总储量、最大持水量和有效拦蓄均最高,分别为14.6 t·hm^-2、2.668 mm和1.43mm,竹阔混交林次之,分别为7.0 t·hm^-2、1.298 mm和0.76 mm,毛竹纯林最低,分别仅为4.7 t·hm^-2、0.916 mm和0.58 mm。(2)5种林分各层枯落物持水量与浸泡时间的关系为:S=k ln(t)+p,在0 - 2 h内,枯落物持水量迅速增加,此后增加速度逐渐减缓;其吸水速率与浸泡时间的关系为:V=at^-1+b,在0 - 1 h内,枯落物吸水速率迅速下降,2 h后下降速度逐渐减缓。(3)竹阔混交林枯落物持水能力虽小于杉木纯林但在竹林中最强,对此,在竹林改造和竹林经营过程中应加以重视。

Study on Function of Litter Water Interception Capacity under Different Bamboo (Phyllostachys edulis) Plantations in the North of Fujian Province

The litter amount and its water holding characteristic parameters,such as the maximum water holding capacity,water absorption rate and the modified interception amount under different typical bamboo plantations (Cunninghamia lanceolata and Phyllostachys edulis mixed stands, P. edulis pure stands and P. edulis and hardwood mixed stands) were studied by regarding C. lanceolata stands and evergreen broadleaved forests as contrasts in northern Fujian Province. The results were as follows:(1)The total amount, maximum water holding capacity and modified interception of litter under different stands were different in undecomposed, half-decomposed and decomposed litters, they were all biggest in half-decomposed litter and the least in undecomposed litter for all the five testing stands, and they were also all the biggest in C. lanceolata pure plantation which followed by P. edulis and hardwood mixed stands and the least in P. edulis pure stands. The total amount, maximum water holding capacity and modified interception of litter were 14.6 t·hm^-2, 7.0 t·hm^-2 and 4.7 t·hm^-2, 2.668 mm, 1.298 mm and 0.916 m, 1.43 mm, 0.76 mm and 0.58 mm respectively in C. lanceolata stands, P. edulis and hardwood mixed stands and P. edulis stands.(2)By analyzing, the relationsip between water holding capacity of litter and immersion time followed the equation of:S=kln(t)+p in five stands, and the litter water capacity increased rapidly within the first two hours, then it increased slowly. While, the equation of the litter absorption rate and immersion time was:V=at^-1+b, and the litter water absobtion rate dropped rapidly within the first hour, then it decreased slowly. (3)Although the litter water holding capacity in P.edulis and hardwood mixed stands was lower than that in C. lanceolata stands, it was the highest among bamboo forests, so it must be fully considered in stands improvement and ecological management of bamboo stands.