地球有多少全球GPP和生物量变化的历史吗?- 江南体育网页版- - - - -地球科学堆江南电子竞技平台栈交换 最近30从www.hoelymoley.com 2023 - 07 - 10 - t13:12:59z //www.hoelymoley.com/feeds/question/2439 https://creativecommons.org/licenses/by-sa/4.0/rdf //www.hoelymoley.com/q/2439 26 地球有多少全球GPP和生物量变化的历史吗? n .处女座 //www.hoelymoley.com/users/215 2014 - 09 - 02 - t09:32:35z 2017 - 09 - 19 - t08:07:51z < p >我很好奇是多少知道这个话题:多少地球上的生命改变的总量在40亿年左右,它已经存在这个星球上?< / p > < p >有估计全球总初级生产力(GPP),或生物量,或者两者兼有,以前的地质时代?如果是这样,如何确定这些估计,假设他们是基于什么?< / p > < p >如果总数据被认为是改变过去,认为造成这些变化的主要因素是什么?相反,如果总被认为是相对稳定的,有哪些主要的反馈被认为是确保呢? < / p > //www.hoelymoley.com/questions/2439/-/2710 # 2710 14 plannapus回答的有多少地球全球GPP和生物量变化的历史吗? plannapus //www.hoelymoley.com/users/87 2014 - 11 - 01 - t10:52:00z 2017 - 09 - 19 - t08:07:51z < p >点回答你的问题:我们不知道。< / p > < p >的生物体,化石记录是不存在的或者非常零碎。甚至估算物种的数量(这是不太困难的,因为你只需要一个样品的每个物种访问信息)是非常困难的,受到很多影响,许多偏见(看到杰克Sepkoski的作品,例如,大卫。罗普和约翰Alroy看到估计过去生物多样性)的难度。尝试重建海洋无脊椎动物多样性(<强> Sepkoski 1978;Alroy et al . 2001, 2008 < /强>)显示在显生宙增加(误差,最后几千万年漫长岁月),有5个主要的大规模灭绝事件(最终奥陶纪、泥盆纪晚二叠纪、三叠纪边界,边界三叠纪、侏罗纪和白垩纪/早第三纪的边界)。< / p > < p >一般的假设是,生物量增加当多样性增加。实在是没有很强的这种假设的基础,但这基本上是所有我们可以处理。< / p > < p >然而一些生物有一个更好的化石记录:硅藻、放射虫、有孔虫和钙质超微化石(主要来自藻类群Haptophyta)构成了大部分的海洋沉积物,因此记录一致且丰富。新生代记录(即过去的66最高产量研究)是相当完整的,但在某些情况下偏见仍足以使我们估算合理丰富的变化。< / p > < p >,事实上,我现在的研究围绕在沉积物硅藻丰度的变化在过去50最高产量研究(<强> Renaudie 2016 < /强>)。 Without going too much into the details, it seems, in that case, that their abundance (in sediments at least) and their diversity are more or loss synced. The interest of diatoms, in regard to your specific question, is that, today, there are one of the two main oceanic primary producers (along with Haptophyta), oceanic production itself being more or less half of the global production (see this previous answer of mine). Their abundance increased significantly at the Eocene/Oligocene boundary and then during the Mid-Miocene. Of course it is possible that in the mean time other phytoplankton (Haptophyta, Dinoflagellates, or others) abundance might have dropped but what makes us think that this is not the case is that changes in diatom abundances during the Cenozoic match changes in atmospheric $p\mathrm{CO}_2$ (Beerling & Royer 2011), implying a global increase in the net primary production.

References:
Alroy, J. et al., 2001. Effects of sampling standardization on estimates of Phanerozoic marine diversification. PNAS, 98(11): 6261-6266.
Alroy, J. et al., 2008. Phanerozoic Trends in the Global Diversity of Marine Invertebrates. Science, 321: 97-100.
Beerling, D. J. & Royer, D. L. 2011. Convergent Cenozoic CO2 history. Nature Geosciences, 4: 418-420.
Renaudie, J. 2016. Quantifying the Cenozoic marine diatom deposition history: links to the C and Si cycles. Biogeosciences, 13: 6003-6014. [Disclaimer: I am the author of this article]
Sepkoski J. J. Jr, 1978. A kinetic model of Phanerozoic taxonomic diversity I. Analysis of marine orders. Paleobiology, 4: 223-251.

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