林窗大小对川西马尾松人工林林下物种多样性和生物量的影响  

Effects of canopy gap size on understory species diversity and biomass in a Pinus massoniana plantation in western Sichuan

作　　者：姚俊宇[1] 伍炫蓓 孙千惠[1] 吴霞[1] 姚小兰[1] 郝建锋[1,2] 齐锦秋 YAO Junyu;WU Xuanbei;SUN Qianhui;WU Xia;YAO Xiaolan;HAO Jianfeng;QI Jinqiu(College of Forestry, Sichuan Agricultural University, Chengdu 611130, China;Key Laboratory of Soil ＆ Water Conservation and Desertification Combating, Chengdu 611130, China;Wood Industry and Furniture Engineering Sichuan Provincial Colleges and Universities Key Laboratory, Chengdu 611130, China)

机构地区：[1]四川农业大学林学院,成都611130 [2]水土保持与荒漠化防治实验室,成都611130 [3]木材工业与家具工程重点实验室,成都611130

出　　处：《应用与环境生物学报》2018年第2期214-220,共7页Chinese Journal of Applied and Environmental Biology

基　　金：四川省教育厅一般项目(15ZB0020);国家自然科学基金项目(31370628);四川农业大学“双支计划”(03571838);国家级大学生创新性实验计划项目(1510626064)资助~~

摘　　要：林窗是植被演替和森林循环的重要驱动力，研究林窗大小对物种多样性和生物量的影响有利于揭示林窗干扰在生态系统恢复中的作用. 以川西莲花山马尾松人工林为研究对象，划分出5种不同面积（81-625 m^2）的林窗共计15个和3个非林窗（林下）作对照（CK），对其群落物种组成、物种多样性水平（丰富度指数D、Simpson优势度指数H’、Shannon-Wiener指数H、Pielou均匀度指数Jsw）和林下生物量（灌木层生物量、草本层生物量）进行调查研究. 结果表明：（1）在总面积为5 493 m^2的样地中，共记录到维管植物99种，隶属56科84属；草本层和灌木层物种数随林窗面积增加均呈单峰格局，前者的物种数变化较后者明显. （2）总的来看，林窗下的D、H、Jsw值较林下大，H’值较林下小，且400-450 m^2面积的林窗下灌木、草本各物种多样性指数值达到一个较高水平. （3）林窗内的生物量显著大于林下生物量，200-250 m^2林窗下的生物量最大. （4）群落各层次物种多样性指数与对应层次地上、地下、全株生物量的相关性均不显著. 因此认为，大面积林窗（400-450 m^2）有利于增加马尾松人工林林下群落物种丰富度，提升林下群落物种多样性水平；而中等面积林窗（200-250 m^2）则有利于增加林下生物量. （图2 表4 参28）Canopy gap is an important driving force for vegetation succession and forest cycle. This study aimed to investigate the effects of natural gap size on understory species diversity and biomass in Pinus massoniana plantations in order to elucidate the function of gap disturbance on ecosystem restoration. Fifteen natural canopy gaps were divided into five different sizes （81–625 m^2）, and three non-gaps served as control groups. Species composition, species diversity （Richness index D, Simpson dominance index H’, Shannon-Wiener diversity index H, and Pielou evenness index Jsw）, and understory biomass （shrub biomass, herb biomass） of P. massoniana plantations were investigated in the Lianhua Mountain, West of Sichuan. （1） Ninety-five plants species, belonging to 56 families and 87 genera, were surveyed in the 5 493 m^2 plot; both the number of herbaceous species number and shrub species showed unimodal patterns with the increase in canopy gap area. However, the species number of herbs exhibited a greater change than that of the shrubs. （2） The D, H, and Jsw indices of the canopy gaps were higher than those of non-gaps, and the H’ index was lower than that of non-gaps. The four species diversity indices reached a high level in the 400–450 m^2 canopy gap area. （3） The biomass of the canopy gaps was significantly higher than the understory biomass, and the biomass in the 200–250 m^2 canopy gap area was the highest. （4） The correlations among the aboveground, belowground, and total biomasses with species diversity indices were not significant. The results showed that large-sized canopy gap （400–450 m^2） increases species richness and promotes species diversity in P. massoniana plantations, and the medium sized canopy gap （200–250 m^2） favors the increase of the understory biomass.

关 键 词：林窗 马尾松人工林 物种多样性 生物量 林下植被 

分 类 号：S753.75[农业科学—森林经理学]