Reproductive output of mosses under experimental warming on Fildes Peninsula, King George Island, maritime Antarctica
Reproductive output of mosses under experimental warming on Fildes Peninsula, King George Island, maritime Antarctica
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DOI：
10.1186/s40693-016-0061-y
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发表时间：
2016-01-01
影响因子：
2.2
通讯作者：
Eppley, S. M.
中科院分区：
文献类型：
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作者：
Casanova-Katny, A.;Torres-Mellado, G. A.;Eppley, S. M.
背景资料：苔藓在南极的植被中占主导地位，但气候变化对苔藓生长和有性繁殖的影响却很少被研究。在南极洲，苔藓很少产生孢子体;这是由于生理限制还是适应性反应尚不清楚。我们研究了实验变暖（开放式顶室，OTCs）对孢子体生产的影响菲尔德斯半岛，国王乔治岛的四种藓类（Bartramia patens，Hennediella anapartica，Polytrichastrum alpinum，Sanionia georgicouncinata）。为了确定减少冷应激是否会增加有性生殖，如果性别受到限制，由于生理上的限制，我们计算了孢子体这四种藓类在OTC和控制地块在两年。此外，我们测量了孢子体的大小为两个物种，B的孢子体较小的样品。patens和H.结果：经过2年的实验治疗，最高日气温，但不是每日平均气温，在OTC内比外面显着更高。我们发现了孢子体产生的显著处理效应，与B的对照相比，OTC中产生的孢子体更多。patens和高山松（P. alpinum）。此外，还观察到B的孢子体。patens和H. anaitica显着较大的OTCs与对照plots.Conclusions相比：我们的研究结果表明，缺乏这些南极苔藓的有性生殖是不适应的，但受到当前环境条件的限制，改善条件，如温度升高可能会影响许多南极苔藓的有性生殖，改变苔藓种群遗传学和传播模式。
Background: Mosses dominate much of the vegetation in the Antarctic, but the effect of climatic change on moss growth and sexual reproduction has scarcely been studied. In Antarctica, mosses infrequently produce sporophytes; whether this is due to physiological limitation or an adaptive response is unknown. We studied the effect of experimental warming (with Open Top Chambers, OTCs) on sporophyte production on Fildes Peninsula, King George Island for four moss species (Bartramia patens, Hennediella antarctica, Polytrichastrum alpinum, and Sanionia georgicouncinata). To determine whether reducing cold stress increases sexual reproduction as would be predicted if sex is being constrained due to physiological limitations, we counted sporophytes for these four moss species in OTC and control plots during two years. Also, we measured sporophyte size for a smaller sample of sporophytes of two species, B. patens and H. antarctica, in the OTC and control plots.Results: After 2 years of the experimental treatment, maximum daily air temperature, but not daily mean air temperature, was significantly higher inside OTCs than outside. We found a significant species by treatment effect for sporophyte production, with more sporophytes produced in OTCs compared with controls for B. patens and P. alpinum. Also, sporophytes of B. patens and H. antarctica were significantly larger in the OTCs compared with the control plots.Conclusions: Our results suggest that the lack of sexual reproduction in these Antarctic mosses is not adaptive but is constrained by current environmental conditions and that ameliorating conditions, such as increased temperature may affect sexual reproduction in many Antarctic mosses, altering moss population genetics and dispersal patterns.