The Species Composition of Soil Seed Banks Beneath Lowland Tropical Rainforests in North Queensland, Australia
The Species Composition of Soil Seed Banks Beneath Lowland Tropical Rainforests in North Queensland, Australia
复制标题
澳大利亚北昆士兰低地热带雨林下土壤种子库的物种组成
DOI：
10.2307/2387950
复制
发表时间：
1983
期刊：
影响因子：
2.1
通讯作者：
A. Graham
中科院分区：
文献类型：
--
作者：
M. Hopkins;A. Graham
从昆士兰北部胡尔姆热带低地的四种热带雨林类型的不同土壤中提取了12个表层土壤样本，并将其移至发芽室条件下，在8月至11月期间对种子萌发进行了14周的监测。四个地点的幼苗数量（平均密度为588 m-2 ~ 1068 m-2）与其他地方采用类似技术在热带雨林土壤中记录的幼苗数量相当。粗质花岗质砂样地的种子萌发数量显著高于细质花岗质砂样地。这是由于种子很容易进入质地粗糙的土壤。所有样地的幼苗大多为次生种或林缘杂草，其中许多是所有样地共有的。一些次生物种在一个或两个站点上的特征丰度通常可以用这些物种在站点上的常绿雨林中的流行度来解释。在取样时，只有少数大种原生林树种发芽，大多数正在结果。种子库中没有许多原始森林树木，这可以用它们种子特有的快速发芽、寿命短的特性来解释。一些原始森林物种可能寿命较长的种子的大尺寸被认为是重要的，可以防止它们被纳入土壤剖面，从而影响它们对捕食的敏感性和在森林地面上的寿命。植物群落土壤中可活种子的组成是该群落再生潜力的一个指标。大多数关于土壤种子储存的研究都是在温带农业和畜牧业环境中进行的，这些信息被用于控制杂草和预测不同管理强度下的成分变化（Milton 1943, 1948; Champness and Morris 1948; Douglas 1965; Suckling and Charlton 1978）。土壤种子研究的结果在预测演代变化和解释过去占据一个区域的植物群落（Oosting and Humphreys 1940, Howard 1974），预测和解释各种强度干扰的结果（Olmsted and Curtis 1947, Floyd 1966, Howard and Ashton 1967, Thompson 1978），以及解释自然更新的途径和单个物种的建立策略（Liew 1973, Baskin and Baskin 1978）方面非常有用。然而，对热带雨林土壤种子的研究很少（Symington 1933, Keay 1960, Guevara and Gomez-Pompa 1972, Liew 1973, Cheke et al. 1979），迫切需要更多的研究（Whitmore 1978）。本文报道了一项研究的结果，该研究旨在确定四个澳大利亚热带雨林地点含有不同土壤的土壤种子库的组成。它是同一地区正在进行的更大规模的次生演替研究的一部分。
Twelve surface soil samples from each of four rainforest types on different soils of the huLmid, tropical lowlands of north Queensland were removed to germination-house conditions, Seed germination was monitored over a period of 14 weeks between AugLst and November. Seedling numbers at the four sites (mean densities ranged from 588 m-2 to 1068 m-2) were comparable to numbers recorded elsewhere by similar techniques in tropical rainforest soils. The numbers of germinated seeds were significantly higher at the site with coarse granitic sands than at the three sites with finer-textured soils. This was attribuLted to the ease with which seeds could be incorporated into the coarse-textured soil. Most of the seedlings produced at all sites were secondary species or weeds of the forest margins, many being common to all sites. The characteristic abundance of some secondary species at one or two sites could be explained usually in terms of the prevalence of those species in the standing rainforest on the sites. Only a few largeseeded primary forest species were germinated and most of these were fruiting at the time of sampling. The absence of many primary forest trees from the seed banks can be explained by the obligately quick-germinating, short-lived natuLre of their seeds. The large size of the potentially longer-lived seeds of some primary forest species was considered to be important in preventing their incorporation in the soil profile and, hence, affecting their susceptibility to predation and longevity on the forest floor. THE COMPOSITION OF VIABLE SEED in soils beneath a plant community is one indicator of the regrowth potential of that community. Most studies of soil seed storage have been conducted in temperate agricultural and pastoral situations where the information has been used to control weeds and predict compositional changes under various intensities of management (Milton 1943, 1948; Champness and Morris 1948; Douglas 1965; Suckling and Charlton 1978). The results of soil seed studies have been useful in predicting successional changes and interpreting past plant communities which occupied an area (Oosting and Humphreys 1940, Howard 1974), predicting and interpreting the results of various intensities of disturbance (Olmsted and Curtis 1947, Floyd 1966, Howard and Ashton 1967, Thompson 1978), and interpreting the pathways of natural regeneration and the strategies of establishment of individual species (Liew 1973, Baskin and Baskin 1978). However, few soil seed studies of tropical rainforests have been conducted (Symington 1933, Keay 1960, Guevara and Gomez-Pompa 1972, Liew 1973, Cheke et al. 1979) and more are urgently required (Whitmore 1978). This paper reports the results of a study designed to define the compositions of the soil seed banks of four Australian tropical rainforest sites containing different soils. It forms part of a larger study of secondary succession which is being carried out in the same area.