Why is Ulva intestinalis the only macroalga inhabiting isolated rockpools along the Swedish Atlantic coast?
Why is Ulva intestinalis the only macroalga inhabiting isolated rockpools along the Swedish Atlantic coast?
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DOI：
10.3354/meps284109
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发表时间：
2004-01-01
影响因子：
2.5
通讯作者：
Beer, S
中科院分区：
文献类型：
--
作者：
Björk, M;Axelsson, L;Beer, S
石莼（以前称为浒苔）是瑞典西海岸沿着孤立岩池中生长的主要海洋大型藻类。考虑到这种藻类可以在高pH值和低浓度无机碳（Ci）的条件下吸收HCO 3-，我们假设这些条件对其他藻类的光合性能不利，使得它们不能在相同的池中生长。这是通过将两种最常见的大型藻类墨角藻和角叉菜从邻近一些岩池的海湾的浅沃茨转移到两个含有U的岩池来测试的。好吧3d后测定光合电子传递速率（ETR）和最大量子产率（F-v/F-m）。类似的测量也进行了一整天，在模拟的室外岩池中，3个物种被单独或一起保持24小时。结果表明，与开放湾相比，岩池中所有物种的午间ETR都受到抑制，但转移的F. vesiculosus和C. crispus（分别为湾值的33和0.6%）比U.（58%）。此外，C. crisp us显示异常抑制中午F-v/F-m值在岩池（约22%，在海湾），并有很大的光漂白后3天。同样，在模拟岩池中，ETRs在白天下降，尤其是C。当其他藻类存在时，crispus（早晨值的7%，单独时为36%）。也就是F-v/F-m。白天在模拟岩池中的下降，F. vesiculosus和C.当其他藻类存在时，crispus（约。12%和10%的早晨值，而单独使用时分别为76%和54%）。就像在岩池中一样，后者在与其他物种一起时会发生光漂白，但单独时不会。基于这些结果。并考虑到它们不同的Ci利用机制，得出的结论是，在岩池中没有藻类，如在这里测试的，可能主要是由于高pH和低Ci浓度的不利条件下所造成的光合特性的U。好吧
Ulva intestinalis (previously called Enteromorpha intestinalis) is the principal marine macroalga growing in isolated rockpools along the Swedish west coast. Given that this alga can take up HCO3- under the conditions of high pH and low concentrations of inorganic carbon (Ci) that it creates in those pools, we hypothesized that those conditions would be unfavourable for the photosynthetic performance of other algae such that the), would not be able to grow in the same pools. This was tested by transferring 2 of the most common macroalgae, Fucus vesicalosus and Chondrus crispus, from the shallow waters of a bay adjacent to some rockpools, to 2 rockpools containing U. intestinalis. Both photosynthetic electron transport rates (ETR) and maximal quantum yields (F-v/F-m) were measured 3 d later. Similar measurements were also performed throughout the day in simulated outdoor rockpools where the 3 species were kept either alone or together for 24 h. It was found that midday ETRs were repressed for all species in the (upper) rockpool as compared to the open bay, but more so for the transferred F. vesiculosus and C. crispus (33 and 0.6%, respectively, of the bay values) than for U. intestinalis (58%). Also, C. crisp us showed exceptionally repressed midday F-v/F-m values in the rockpools (some 22% of that in the bay), and had largely photobleached alter 3 d. Similarly, ETRs declined in the simulated rockpools during the day, especially for C. crispus when the other algae were present (to 7% of morning values, compared to 36% when alone). Also, F-v/F-m. declined in the simulated rockpools during the day, indeed much more so for F. vesiculosus and C. crispus when the other algae were present (to ca. 12 and 10% of morning values as compared to 76 and 54%, respectively, when alone). As in the rockpools, the latter alga photobleached when kept together with the other species, but not when alone. Based on these results. and considering their different Ci utilisation mechanisms, it was concluded that the absence in rockpools of algae such as those tested here may be largely due to the adverse conditions of high pH and low Ci concentrations caused by the photosynthetic traits of U. intestinalis.