华南退化草坡自然恢复中物种多度分布的动态与模拟  

Dynamics and modeling of species abundance distribution during natural restoration of degraded hilly grassland in south China

作　　者：殷祚云[1,2] 任海[2] 彭少麟[3] 郭勤峰[4] 曾令海[1] 贺骁[5] 

机构地区：[1]广东省林业科学研究院,广东广州510520 [2]中国科学院华南植物园,广东广州510650 [3]中山大学生命科学学院,广东广州510275 [4]美国农业部东部森林威胁评估中心,美国Asheville NC 28804 [5]广东商学院经济贸易与统计学院,广东广州510320

出　　处：《生态环境学报》2009年第1期222-228,共7页Ecology and Environmental Sciences

基　　金：广东省自然科学基金项目(06300348,07118249);国家自然科学基金项目(40871249)

摘　　要：华南地区退化草坡自然恢复过程中物种多度格局的动态及其模拟,尚缺乏较为系统的研究。文章探讨是否不同演替阶段群落适合不同的种多度模型,是否存在一个最佳模型以揭示演替过程中群落结构的某些内在数量特征;还要推导多个模型的尺度转换形式。为此,在地处南亚热带的鹤山退化草坡选取处于不同演替阶段的2个典型群落样地,分木本层和草本层调查每个维管植物种的多度;且选择7个具有不同函数形式和广泛代表性的种多度模型,均在倍程(即log2)尺度下拟合数据,运用卡方检验和调整决定系数评估各个模型的适合性。结果表明:(1)7个模型的适合性顺序为:对数柯西>对数双曲正割>对数正态>对数级数>生态位优先占领>断棒>重叠生态位,其中对数柯西适合全部数据,重叠生态位则全部不适合;(2)各模型适合与否和演替阶段无关;(3)左截断对数柯西模型预测的种多度分布显示,随着群落演替,上层(木本层)罕见种比例减少、常见种比例增多,下层(草本层)则相反,这与实际相符。对数柯西分布具有普适性,能最好地反映退化草坡自然恢复中种多度分布的格局与动态。Comprehensive studies on dynamics and modeling of species abundance patterns during the natural restoration of the degraded hilly grassland in South China are relatively rare. Here we explore whether communities in different successional stages follow different species abundance models and whether there is a best model that can reveal some of the intrinsic quantitative characteristics of community structure in succession. We also attempt to derive the scale transformation of several models of species abundances. We use the abundance data of each vascular plant from both wood and herb layers within two typical communities of different succesional stages in the degraded hilly grassland of lower subtropical Heshan, Guandong, China. Seven widely representative species abundance models with obviously different function forms are synchronously selected to fit each dataset on octave （i.e., log2） scale, and the goodness-of-fits are evaluated using both chi-squared tests and the adjusted coefficients of determination. The results show that： （1） the order in goodness-of-fit is： logCauchy 〉 log-sech 〉 lognormal 〉 logseries 〉 niche pre-emption 〉 broken stick 〉 overlapping niche, and the logCauchy follow all the datasets while the overlapping niche fits none, （2） the fit of each model to observation is not directly related to successional stage, and （3） in both the left-truncated species abundance distributions fitted by the logCauchy and field observation, for the proportion of number of species, the rare species decreased but the common ones increased in the upper layer （i.e., wood layer） with succession while the reverse is true in the lower layer （i.e., herb layer）. Therefore, we conclude that the logCauchy distribution has the widest applicability, and can best mirror the patterns and dynamics of species abundances during the natural restoration of the degraded hilly grassland.

关 键 词：退化草坡 自然恢复 物种多度分布 模型 动态 

分 类 号：X142[环境科学与工程—环境科学]