The effect of environmental factors on field and laboratory germination in a population of Zostera marina L. from southern England
The effect of environmental factors on field and laboratory germination in a population of Zostera marina L. from southern England
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DOI：
10.1017/s0960258599000343
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发表时间：
1999-12-01
影响因子：
2.1
通讯作者：
Brenchley, JL
中科院分区：
文献类型：
--
作者：
Probert, RJ;Brenchley, JL
研究了温度、氧供应量和盐度对大叶藻种子萌发的影响。在实验室里对英国南部的一个潮汐泻湖--弗利特湖的海水进行了研究。全年还从岩芯样品和用尼龙袋埋在沉积层中的种子样品中监测种子在自然条件下的命运。在研究地点进行的温度、盐度和含氧量测量的支持下，实地数据证实，9月/10月种子传播后，大部分种子在冬季和早春在船队中发芽。在实验室中，与有氧条件相比，在厌氧条件下种子发芽更快，最终百分比更高。在厌氧条件下，快速，接近完全发芽是可能的，在全盐度（30克升（-1））或当盐度降低了50%（15克升（-1））。在有氧条件下，种子发芽更迅速，在较低的盐度。温度的影响强烈地依赖于氧的存在或不存在。在厌氧条件下，有一个明显的最佳恒温发芽约6摄氏度，密切对应的平均水温记录在10月中旬至3月底。另一方面，在有氧条件下，在低温下记录到非常低的发芽水平。这些发现支持了先前发表的证据，即Z。海洋生物非常适合在厌氧沉积物中发芽，水温是决定自然条件下发芽时间的关键环境变量。以前的误用休眠术语来描述种子种群的Z。Marina正在讨论。
The effects of temperature, oxygen availability and salinity on seed germination in a population of Zostera marina L. from the Fleet, a tidal lagoon in southern England, were investigated in the laboratory. The fate of seeds under natural conditions was also monitored throughout the year from core samples and from seed samples buried in the sediment layer in nylon sachets. Supported with temperature, salinity and oxygen level measurements at the study site, field data confirmed that following seed dispersal in September/October, the majority of seeds germinated in the Fleet during the winter and early spring. In the laboratory, seeds germinated more rapidly and to a higher final percentage under anaerobic conditions compared to aerobic conditions. Under anaerobic conditions, rapid, near complete germination was possible at full salinity (30 g l(-1)) or when the salinity was reduced by 50% (15 g l(-1)). Under aerobic conditions, seeds germinated more rapidly at lower salinity. The effects of temperature were strongly dependent on the presence or absence of oxygen. Under anaerobic conditions, there was a pronounced optimum constant temperature for germination around 6 degrees C, corresponding closely to the average water temperature recorded during the period mid-October to the end of March. On the other hand, under aerobic conditions, very low levels of germination were recorded at low temperatures. These findings support previously published evidence that seeds of Z. marina are well adapted to germinate in anaerobic sediments and that water temperature is the key environmental variable that determines the timing of germination under natural conditions. Previous misuse of dormancy terms to describe seed populations of Z. marina is discussed.