柏木低效林不同改造模式优势草本植物多样性及其生态位  

Study on plant diversity and niche characteristics of dominant herbaceous populations under different reconstruction patterns in low efficiency stands of Cupressus funebris

作　　者：陈丝露 赵敏 李贤伟[1] 范川[1] 肖宝茹 

机构地区：[1]四川农业大学林学院长江上游林业生态工程四川省重点实验室,成都611130 [2]德阳市林业局,德阳618000

出　　处：《生态学报》2018年第1期143-155,共13页Acta Ecologica Sinica

基　　金：国家"十二五"科技支撑项目(2011BAC09B05);德国政府贷款四川林业可持续经营管理项目(003H0602);国家林业局中央财政林业科技推广示范(2010TK55);四川省科技支撑计划(2010NZ0049)

摘　　要：草本层对森林生态系统具有重要的作用,其对于环境的变化比乔木层和灌木层更为敏感,在较短的时间内更容易反映改造带来的影响。为了分析林分改造后草本植物多样性的变化和揭示草本群落间的关系,以川中丘陵区改造4 a后的11种模式:不同密度(株行距1.5 m×4 m与1.5 m×2 m)的桤木(Alnus cremastogyne)、香椿(Toona sinensis)、银木(Cinnamomum septentrionale)纯林模式和株行距为1.5 m×2 m的银木+桤木模式、香椿+银木模式、香椿+桤木模式、桤木+香椿+银木模式以及采伐迹地作为研究对象,柏木(Cupressus funebris)纯林为对照,对柏木低效林不同改造模式的优势草本植物多样性、生态位宽度及生态位重叠进行研究。结果表明:(1)除高低密度香椿模式、低密度银木模式和桤木+香椿+银木模式外,其他模式的草本植物多样性均优于柏木纯林,其中以香椿+银木模式(Shannon-Wiener指数、Simpson指数、均匀度和丰富度指数分别为(1.82、0.83、0.94和1.30),与香椿+桤木模式(1.83、0.83、0.93和1.33)的生物多样性显著高于柏木纯林(1.48、0.69、0.82和1.27),为最优的改造模式。(2)改造前铁线蕨(Adiantum capillus-veneris)生态位宽度最广为2.365,喜阴植物占有优势地位,改造后林下光照环境发生变化,喜阳植物五节芒(Miscanthus floridulus)在低密度的纯林模式中迅速占据林下生长空间,生态位宽度较大,随改造模式郁闭度的增加,薹草(Carex tristachya)、地果(Ficus tikoua)、竹叶草(Oplismenus compositus)等喜阴植物逐渐占据优势地位,喜阳植物逐渐被淘汰。生态位宽度的大小与重要值呈极显著正相关关系(r=0.916),但也与资源位呈极显著正相关关系(r=0.977)。(3)生态位宽度较大的物种间既有较大的生态位重叠,也有较小的生态位重叠,不能仅凭生态位宽度来判定生态位重叠值,而生态位宽度较小的鼠麴草(Gnaphalium affine)(0.647)与蛇莓(Duchesnea indica)(2.15Herbaceous layer plays a very important role in a forest ecosystem; it is more sensitive to environment than the arborous and shrub layers. Changes in herbaceous communities are more likely to reflect the effects of transformation in a relatively short period. To analyze the diversity of herbaceous plants after reconstruction and reveal the ecological relationships of herbaceous communities, pure forest plantations of Cinnamomum septentrionale, Alnus cremastogyne, and Toona sinensis and mixed plantations of C. septentrionale ＋ A. cremastogyne, Cinnamomum septentrionale ＋ T. sinensis, T. sinensis ＋ A. cremastogyne, and C. septentrionale ＋ A. cremastogyne ＋ T. sinensis were studied The cutting-blank were selected as the research object, whereas the pure C. funebris forest was used as contrast. Pure forest plantations exhibit high and low planting densities, i.e. a spacing of 1.5 m×2 m and 1.5 m×4 m, respectively. Planting spacing in mixed plantations is 1.5 m×2 m. The results were as follows：（1） The Shannon-Wiener index, Simpson＇s index, Pielou＇s index and richness index of reconstruction plantation types were higher than those of the pure C. funebris forest （1.48, 0.69, 0.82, and 1.27, respectively）, except low and high density pure T.sinensis plantation （1.19, 0.65, 0.86, and 0.66, respectively） （1.30, 0.65, 0.72, and 1.15, respectively）, low density pure C. septentrionale plantation （1.48, 0.76, 0.92, and 0.85, respectively） and C. septentrionale ＋ A. cremastogyne ＋ T. sinensis plantation （1.44, 0.72, 0.81, and 1.12, respectively）. Among all planting patterns, the biological diversity indices of mixed plantations of C. septentrionale ＋ T. sinensis （1.83, 0.83, 0.94, and 1.30, respectively） and A. cremastogyne ＋ T. sinensis （1.82, 0.83, 0.93, and 1.33, respectively） were significantly higher than those of the pure C. funebris forest; the two mixed plantation types were the relatively optimal reconstruction types. （2） The Adiantum capillus-veneris had

关 键 词：柏木 低效林 植物多样性 生态位 改造模式 

分 类 号：S718.5[农业科学—林学]