Linking global change and deep-sea macrobenthos diversity – bathyal Atelostomata as a model taxon.

将全球变化与深海大型底栖动物多样性联系起来 – 深海 Atelostomata 作为模型分类单元。

• 批准号: 408168002
• 负责人: Privatdozent Dr. Frank Wiese
• 金额: --
• 依托单位: Abteilung Geobiologie
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/408168002?language=en
• 关键词: Linking; global; change; deep; sea

The deep-sea is the Earth’s largest ecosystem, and due to its sheer size and inaccessibility, our knowledge on global deep-sea biota and its controlling mechanisms is still ambiguous. While chemosynthetic ecosystems are progressively understood, the bathyal to abyssal plains and the hadal deep-sea trenches remain widely unexplored. Due to the scarce geologic record of deep-sea sediments onshore and the lack of continuous geological/palaeontological records of any group of higher deep-sea Metazoa, our knowledge on deep-sea palaeobiogeography and macrofauna evolution is even more rudimentary. A survey to extract remains of deep-sea macrobenthos from Lower Cretaceous to Upper Miocene sediments deposited at deep bathyal palaeo-waterdepths below 2000 m in ODP/DSDP/IODP core samples yielded astonishing results: Echinodermata (holothurians, brittle stars, sea stars, crinoids), today common in the deep-sea, are absent, while only spines of irregular echinoids (Holasteroida, Spatangoida: Atelostomata) occur frequently. Because the spines are morphologically highly variable, the assessment of spine morphospace, its changes in time and the spine accumulation rate bears the potential to map diversity and biomass changes in the deep-sea in response to global change. In particular, global warming results in decreasing export productivity due to lower primary productivity especially in open oceanic settings, why the eastern tropical Pacific serves as a model area to clarify two hypotheses. i) Atelostomate spine diversity correlates inversely with Cenozoic warm periods, supporting the productivity-diversity relation and ii) atelostomate spine abundance is expression of biomass and export productivity, showing lower values in warm phases. Atelostomate spines from selected intervals of the rapidly changing Cenozoic world with massive sea surface and bottom water temperature changes and were considered (Mid-Miocene cooling, Mid-Miocene climatic optimum, late Oligocene warming; Oi-2c glaciation and aftermath, Upper Oligocene; Oi-2b glaciation and aftermath). Spine characters (e.g. shaft morphology, arrangement and frequency of thorns, shape/number of pores, shape of tips etc.) are included in a data matrix and statistically processed. Variations in spine diversity are considered to express changing biodiversity, and decreasing diversity and biomass is expected during warming periods. A principal component analyses of the spine assemblages from the intervals above aid the recognition of morphospace disparity between the time-specific intervals and diversity changes. This give additionally clues on gradual (evolution?) or abrupt (extinction and speciation/immigration?) faunal changes between the deep-sea Atleostomata and the relation of faunal turnovers/changes to fluctuating export productivity into the dee-sea during global change.

深海是地球上最大的生态系统，由于它的巨大规模和难以进入，我们对全球深海生物群及其控制机制的了解仍然不明确。虽然人们逐渐了解了化学合成生态系统，但半深海到深海平原和哈达尔深海海沟仍然广泛未被开发。由于陆上深海沉积物地质记录的稀缺，以及深海高等后生动物群的连续地质/古生物记录的缺乏，我们对深海古生物地理和大型动物演化的认识更加粗浅。通过对大洋下白垩统至上中新世深海大型底栖动物遗骸的提取，发现了一些令人震惊的结果：如今在深海中常见的棘皮动物(海鞘动物、脆星动物、海星动物、海星动物)不存在，而只有不规则的棘皮动物脊骨(海鞘动物纲、甲壳动物纲：无口棘目)频繁出现。由于脊椎在形态上是高度可变的，对脊椎形态空间、其时间变化和脊椎积累速率的评估有可能绘制深海生物多样性和生物量变化图，以应对全球变化。特别是，全球变暖导致出口生产力下降，因为初级生产力降低，特别是在开阔的海洋环境中，为什么东热带太平洋是澄清两个假设的模型区。1)无口脊椎多样性与新生代暖期呈负相关，支持生产力-多样性关系；2)无口脊椎丰度是生物量和输出生产力的反映，在暖期表现出较低的数值。在快速变化的新生代，海面和底层水温发生了巨大变化的选定时段有无口棘，并被认为是(中中新世降温、中中新世气候最佳、晚渐新世变暖；OI-2c冰川作用和后果、上渐新世；OI-2b冰川作用和后果)。脊椎特征(例如，刺的形状、排列和频率、毛孔的形状/数量、尖端的形状等)包括在数据矩阵中并进行统计处理。脊椎多样性的变化被认为表明了生物多样性的变化，预计在变暖期间多样性和生物量将会减少。对上述间隔的脊椎组合进行主成分分析有助于识别特定时间间隔之间的形态空间差异和多样性变化。这为渐进(进化？)提供了额外的线索。或者突然(灭绝和物种形成/移民？)在全球变化期间，深海气孔之间的动物群变化和动物群周转/变化与流入深海的波动的出口生产力之间的关系。