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理论生物学——至少可以有,或应该有,还是地球上的一个“南方针叶林”?

我遇到过的所有数据的针叶林“磁极周围”,巨大的寒冷森林主要由松柏门树,是关于北极周围的森林从斯堪的纳维亚半岛北部和欧洲北部俄罗斯西伯利亚北部和加拿大北部。

考虑森林地区靠近一点南部极,南巴塔哥尼亚(南美南部的极端)北部森林的使我想起了一个;植被和新西兰和诺福克岛(可能主要是人工岛屿)一点,或许paleoentological在南极洲发现树过去将更像一个“泰加林”。

理论生物学——至少可以有,或应该有,还是地球上的一个“南方针叶林”?

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我将定义一个北方森林的地方,1。树,即。长寿的木本植物,生长的至少10米高和生长都向上通过扩展新的分支和扩大对外的主干。在其他的事情,这排除了次~ 3.8亿年前,第一个树木形成的时候。2。有足够的树,构成一片森林,我将定义一个稍大的区域树木生长足够致密,形成一个或多或少的树冠。这个区别森林地区只有几棵树热带稀树草原和高山矮曲林等。3所示。有非常严酷的冬天,至少一个月的平均温度远低于冰点,和-40°C的温度并不罕见。这种区分从寒冷的北方森林海洋森林等(麦哲伦亚寒带森林)(https://en.wikipedia.org/wiki/Magellanic_subpolar_forests)在智利和阿根廷南部。4。 Has mild summers, with only a few months where the average temperature exceeds 10° C. This distinguishes boreal forests from hemiboreal and temperate forests. Note that some scientists do not make this distinction, classifying Köppen climate zone Dfb as boreal. 5. Is extensive. This distinguishes large boreal forests from high altitude subalpine forests that would locally pass the above tests. Subalpine forests can occur at any latitude, including [Australia's Snow Mountains](https://en.wikipedia.org/wiki/Snowy_Mountains), New Zealand's [Southern Alps](https://en.wikipedia.org/wiki/Southern_Alps), and parts of the Andes. This is not a clear-cut boundary. As a climate cools, subalpine forests may spread to the valleys between mountains and then spread out beyond the mountains. At some point, such montane forests becomes boreal forests. The need for very harsh winters coupled with the need for extensiveness means that boreal forests did not exist between the start of the Triassic ~252 million years ago to the end of the Eocene ~34 million years ago. The Earth was in its greenhouse phase during that long stretch of time, with balmy temperatures year round even at the poles. A boreal forest can only exist when the Earth is in its icehouse phase. This includes the last 34 million years, and also the period between 340 to 250, the late Paleozoic glaciation. Unlike the current ice age, the Earth in the late Paleozoic had land (Gondwana) surrounding the South Pole. The question then is whether either of those intervals (the last ~34 million years, and the late Paleozoic glaciation) have supported a southern boreal forest. Per *Rees-Owens et al.*, the answer is a possible yes to the more recent interval. Forests existed on Antarctica until as recently as 2.5 million years ago. Whether these were Köppen climate zone Cfc (subpolar) or Dfc (continental boreal) is very hard to say. If one relaxes the requirement for cold winters a bit, then those recent forests almost certainly were boreal. Per *Horton, et al.*, and also per the authors of several related papers, the answer is an unequivocal yes to the more ancient interval. Moreover, the boreal forest of that ancient time would have been very much like the boreal forest of present time: One of the largest ecozones on the planet. <br> References: [Horton, D.E., Poulsen, C.J. and Pollard, D., 2010. Influence of high-latitude vegetation feedbacks on late Palaeozoic glacial cycles. Nature Geoscience, 3(8), p.572.](https://www.nature.com/articles/ngeo922) [Pross, J., Contreras, L., Bijl, P.K., Greenwood, D.R., Bohaty, S.M., Schouten, S., Bendle, J.A., Röhl, U., Tauxe, L., Raine, J.I. and Huck, C.E., 2012. Persistent near-tropical warmth on the Antarctic continent during the early Eocene epoch. *Nature*, 488(7409), p.73.](https://www.nature.com/articles/nature11300) [Rees-Owen, R.L., Gill, F.L., Newton, R.J., Ivanović, R.F., Francis, J.E., Riding, J.B., Vane, C.H. and dos Santos, R.A.L., 2018. The last forests on Antarctica: Reconstructing flora and temperature from the Neogene Sirius Group, Transantarctic Mountains. *Organic Geochemistry*, 118, pp.4-14.](https://www.sciencedirect.com/science/article/pii/S014663801730219X)

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\ begingroup美元 + 1好开始。我在想沿着这条线的东西:我们必须寻找一个安排,允许为大陆性气候,即在南极洲和澳大利亚分离。然后我们在一系列针叶林正如我们所知,不存在仅仅是因为一些类群及其社区与其他生物不存在。可能的答案会是“不,针叶林像我们知道不,在南半球不存在”。也许类似的东西。similarness程度必须定义:-) \ endgroup美元
- - - - - -user18411
在2019年12月28日
2

\ begingroup美元 @ebv——谢谢。我写了大量的研究和大量的时间,但它只是一个“好开始”。我将更新。请添加你的两位。$ $ \ \ $ $的泰加林晚古生代会相当不同于遥远的北方针叶林的今天,原因很简单,生活的发展。但在某些方面它会看起来相似,有“树木”,形成广泛的森林,和冬天是脏话的删除。 \ endgroup美元
- - - - - -大卫Hammen
2019年12月28日,在10:56

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