The Interaction of Soil and Lake Microflora at Signy Island
The Interaction of Soil and Lake Microflora at Signy Island
复制标题
西格尼岛土壤和湖泊微生物区系的相互作用
DOI：
10.1007/978-3-642-82275-9_92
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
D. Wynn
中科院分区：
文献类型：
--
作者：
J. Ellis;D. Wynn
锡尼的湖泊很小，在夏季无冰期间，从周围集水区接收大量流入的径流，大大超过其总容量。在每个湖泊集水区的各种生境中，存在着大量的细菌、酵母菌和真菌。湖泊表面沃茨中的色杆菌和酵母菌的出现证明了陆地微生物区系在径流水中向湖泊的运输，同时它们的数量在某些陆地栖息地中增加。然而，仔细检查发现湖泊和陆地种群之间存在很大差异，可能最明显的是湖泊样本中几乎没有革兰氏阳性细菌，而陆地种群占20%。通过数字剖面，可以证明湖泊种群的组成在湖泊之间以及湖泊与其集水区种群之间存在差异。这些差异可以从流域组成和养分供应方面加以解释。对特定温度生长速率特征的研究表明，从广义上讲，成功的淡水细菌可以被视为嗜冷菌，而成功的陆地细菌则更具耐冷性。底物亲和力值的比较表明，淡水细菌是更有效的比陆地细菌或酵母菌在利用低浓度的溶解有机碳在低温下。在较高温度下，底物亲和力值更等效。从所提供的数据，它是建议，这两个群体可以被认为是一个混合文化恒化器人口。在高营养浓度下，将存在典型的陆地种群，随着温度和营养水平的波动，也将发生典型的演替。但是，当营养水平在很长一段时间内突然下降，温度稳定在0 °C左右时，就会出现一个典型的淡水种群，其组成部分以前只存在于非常低的数量。
Lakes on Signy are small and, during the summer ice-free period, receive a substantial influx of run-off from the surrounding catchment, greatly in excess of their total volume. Within the various habitats comprising each lake’s catchment area, large populations of bacteria, yeasts and fungi exist. Transport of terrestrial micro-flora to the lakes in run-off water is demonstrated by the appearance ofChromobacteriumand yeasts in lake surface waters at around the same time as their numbers increase in certain terrestrial habitats. However, close examination reveals substantial differences between lake and terrestrial populations, possibly the most obvious being the virtual absence of gram-positive bacteria from lake samples whilst comprising 20% of terrestrial populations. By means of numerical profiles, it has been possible to demonstrate that the composition of lake populations differs between lakes, and between lakes and their catchment populations. These differences can be explained in terms of catchment composition and nutrient availability. A study of temperature-specific growth rate characteristics indicates that successful freshwater bacteria can, in broad terms, be considered psychrophiles, whereas successful terrestrial bacteria are more psychrotolerant. A comparison of substrate affinity values indicates that freshwater bacteria are more efficient than terrestrial bacteria or yeasts in utilizing low concentrations of dissolved organic C at low temperatures. At higher temperatures, substrate affinity values are more equivalent. From the data presented, it is proposed that the two populations may be considered as a mixed-culture chemostat population. At high nutrient concentrations, a typical terrestrial population will exist and with fluctuations in temperature and nutrient level, a typical succession will also occur. But when nutrient levels drop suddenly for an extended period and temperature stabilizes at about 0 °C, a typical freshwater population emerges whose components had previously existed only in very low numbers.