Willey N J, Martin M H
Faculty of Applied Sciences, University of the West of England, Bristol, BS16 1QY, UK.
Environ Pollut. 1997;95(3):311-7. doi: 10.1016/s0269-7491(96)00144-3.
Six plant species in the family Gramineae were used to investigate the relationship between Cs uptake, nutrient regime and plant growth strategy sensu Grime (1979: Plant Growth Strategies and Vegetation Processes, John Wiley). The roots of 66 day old Elymus repens (L.) Gould., Bromus sterilis L., Agrostis stolonifera L., Anthoxanthum odoratum L., Festuca ovina L. and Nardus stricta L. plants grown in acid-washed sand at high and low nutrient levels were exposed to a 96 h pulse of stable Cs at 0.05 mM, 0.15 mM, 0.3 mM, 1.0 mM and 3.0 mM concentrations. Different nutrient regimes induced large differences in dry wt in E. repens, B. sterilis and A. stolonifera plants but only small differences in N. stricta and F. ovina plants. At high nutrient concentrations, A. stolonifera, A. odoratum, F. ovina and N. stricta shoots showed significantly greater increases in internal Cs concentration with rising external Cs concentrations than did E. repens and B. sterilis shoots. The relationship between increases in shoot and external Cs concentrations was statistically indistinguishable between species in plants grown at the low nutrient concentration. These patterns of Cs uptake ensured that with long-term high K concentrations the more competitive plants (E. repens and B. sterilis) accumulated higher concentrations of Cs from low external concentrations than did non-competitive plants or competitive plants grown at low nutrient levels. It is suggested that the relationship between plant growth strategy sensu Grime (1979) and Cs accumulation patterns may help to explain the different concentrations to which species accumulate radiocaesium from the soil.
禾本科的六种植物被用于研究铯吸收、养分状况与植物生长策略（参照Grime，1979年：《植物生长策略与植被过程》，约翰·威利出版社）之间的关系。将66日龄的偃麦草（Elymus repens (L.) Gould.）、无芒雀麦（Bromus sterilis L.）、匍匐翦股颖（Agrostis stolonifera L.）、黄花茅（Anthoxanthum odoratum L.）、羊茅（Festuca ovina L.）和硬羊茅（Nardus stricta L.）植株种植在高、低养分水平的酸洗砂中，其根系暴露于浓度为0.05 mM、0.15 mM、0.3 mM、1.0 mM和3.0 mM的稳定铯溶液中96小时。不同的养分状况导致偃麦草、无芒雀麦和匍匐翦股颖植株的干重差异很大，但硬羊茅和羊茅植株的差异很小。在高养分浓度下，与偃麦草和无芒雀麦的地上部分相比，匍匐翦股颖、黄花茅、羊茅和硬羊茅的地上部分内部铯浓度随外部铯浓度升高而显著增加。在低养分浓度下生长的植株中，各物种地上部分铯浓度增加与外部铯浓度之间的关系在统计学上没有差异。这些铯吸收模式确保了在长期高钾浓度条件下，更具竞争力的植物（偃麦草和无芒雀麦）比非竞争性植物或在低养分水平下生长的竞争性植物从低外部浓度中积累更高浓度的铯。研究表明，Grime（1979年）提出的植物生长策略与铯积累模式之间的关系可能有助于解释不同物种从土壤中积累放射性铯的不同浓度。
