Feng Zhuo, Gou Xu-Dong, McLoughlin Stephen, Wei Hai-Bo, Guo Yun
Institute of Palaeontology & Yunnan Key Laboratory of Earth System Science & Yunnan Key Laboratory for Palaeobiology & MEC International Joint Laboratory for Palaeobiology and Palaeoenvironment, Yunnan University, Kunming 650500, China.
Graduate Department, Kunming University, Kunming 650214, China.
iScience. 2022 Oct 26;25(11):105433. doi: 10.1016/j.isci.2022.105433. eCollection 2022 Nov 18.
Nurse logs are common in modern forests from boreal to temperate and tropical ecosystems. However, the evolution of the nurse-log strategy remains elusive because of their rare occurrence in the fossil record. We report seven coniferous nurse logs from lowermost to uppermost Permian strata of northern China that have been colonized by conifer and sphenophyllalean roots. These roots are associated with two types of arthropod coprolites and fungal remains. Our study provides the first glimpse into plant-plant facilitative relationships between late Paleozoic gymnosperms and sphenopsids. Detritivorous arthropods and fungi appear to have been crucial for the utilization of nurse logs in Permian forests. The phylogenetically distant roots demonstrate that nurse-log interaction was a sophisticated seedling strategy in late Paleozoic humid tropical forests, and this approach may have been adopted and developed by a succession of plant groups leading to its wide representation in modern forest ecosystems.
护根在从寒温带至温带和热带生态系统的现代森林中很常见。然而，由于护根在化石记录中很少出现，其演化过程仍然难以捉摸。我们报告了来自中国北方二叠纪最底层至最上层地层的七根针叶树护根，这些护根已被针叶树和楔叶类植物的根系所占据。这些根系与两种节肢动物粪便化石和真菌遗迹有关。我们的研究首次揭示了晚古生代裸子植物和楔叶类植物之间的植物-植物促进关系。食碎屑节肢动物和真菌似乎对二叠纪森林中护根的利用至关重要。系统发育关系较远的根系表明，护根相互作用是晚古生代潮湿热带森林中一种复杂的幼苗策略，并且这种方法可能被一系列植物类群采用和发展，从而在现代森林生态系统中广泛存在。
