Biodiversity development of terrestrial testate amoebae: is there any succession at all?
Biodiversity development of terrestrial testate amoebae: is there any succession at all?
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陆地睾丸变形虫的生物多样性发展：是否有任何演替？
DOI：
10.1007/s00374-005-0850-y
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发表时间：
2005
影响因子：
6.5
通讯作者：
W. Xylander
中科院分区：
文献类型：
--
作者：
M. Wanner;W. Xylander
异养原生生物（如有壳变形虫）在原生演替中起着重要作用，因为这些单细胞生物体以高丰度和生物量立即出现在新暴露的陆地表面，促进了植物和动物的建立。我们调查了不同年龄和演替阶段的土壤中有壳变形虫，即使在非常干燥的地方，也显示出非常高的丰度和生物量。重点放在两个内陆沙丘的不同植物演替阶段（裸砂，Corynephorus canescens和毛状金发藓作为早期阶段，羊茅和樟子松作为晚期阶段）的微年代序列。有遗嘱的变形虫物种的数量明显增加植被覆盖的演替阶段，但没有一致的更换或灭绝的类群观察。“新来者”显然没有减少“居民”的密度，虽然社区模式（丰度，生物量，优势）显着改变。暴露在空气中或附近的土壤中的不同质量的无有机体基质被快速和高丰度的有壳阿米巴定殖，但没有发生物种的时间更替。聚类分析的物种库存和丰富的多种类型的土壤不同年龄的突出分类阿米巴社区对区域的影响，而不是当地的植被演替阶段。这些数据证实了这样一个事实，即地下社区的运作不同于植物群落，因为它们的特点是添加剂入侵，而不是种间竞争。这是典型的中立社区模式。
Heterotrophic protists (e.g. testate amoebae) play an important part in primary succession because these unicellular organisms occur immediately at newly exposed land surfaces in high abundances and biomasses, facilitating the establishment of plants and animals. We investigated testate amoebae from soils of different age and successional stage, which revealed remarkably high abundances and biomasses even at very dry sites. Emphasis was set on two inland dune microchronosequences of different plant successional stages (bare sand, Corynephorus canescens and Polytrichum piliferum as early stages; Festuca ovina and Pinus sylvestris as late stages). The number of testate amoebae species increased clearly with the successional stage of the vegetation cover, but no consistent replacement or extinction of taxa was observed. The “newcomers” obviously did not reduce the density of the “residents”, although the community pattern (abundances, biomasses, dominances) was significantly altered. Organism-free substrate of different quality exposed to the air or adjacent soil was colonised quickly and in high abundance by testate amoebae, but no temporal replacement of species occurred. Cluster analysis of species inventory and abundances of numerous types of soil of different age highlight a classification of amoebal communities towards regional influences rather than local successional stages of vegetation. These data corroborate the fact that belowground communities operate differently from plant communitites in that they are characterised by additive invasion and not by interspecific competition. This is typical for a neutral community model.