Deadly oasis:Recurrent annihilation of Cretaceous desert bryophyte colonies;the role of solar,climate and lithospheric forcing  

作　　者：Juan Pedro Rodríguez-Lópeza Eduardo Barrón Daniel Peyrot Gary B.Hughes 

机构地区：[1]Department of Geology.Faculty of Science.United Arab Emirates University.50009.Al Ain,Abu Dhabi,United Arab Emirates [2]Instituto Geológico y Minero de Espana(IGME),Ríos Rosas 23,E-28003,Madrid,Spain [3]School of Earth and Environment,University of Western Australia.6101,Crawley,Western Australia,Australia [4]Centre for Energy Geosciences,University of Western Australia.6101,Crawley,Western Australia,Australia [5]Physics Department,University of California,Santa Barbara,CA,93106,USA

出　　处：《Geoscience Frontiers》2021年第1期1-12,共12页地学前缘（英文版）

基　　金：financed by the Project CRE:“Cretaceous Resin Event:Global bioevent of massive resin production at the initial diversification of modern forest ecosystems”;funded by the Spanish AEI/FEDER,UE Grant CGL2017-84419;Funded by the CGL2005-07445-C03-03 and CGL201123717 projects of the Ministry of Education of the Government of Spain。

摘　　要：Many oases(wet interdunes)are sedimentary systems characterized by high-frequency water-level oscillations,marked changes in salinity and intense biological activity at their margins.They are considered to be one of the most challenging environments on Earth for ecosystem development.These dynamic,depositional settings are usually unfavourable for fossilization and subsequent preservation of vegetal remains.This paper describes bryophyte(liverwort)assemblages occurring in three successive horizons interpreted to represent(i)recurrent early successional phases of biological soil crust colonization of wet interdune margins or(ii)exceptional preservation of floating or riparian liverworts in oasis pond waters associated with a progressive fall of the interdune water level.The record of in situ colonization surfaces characterized by delicate(e.g.lignin-free)three-dimensional structures represents an exceptional type of preservation herein associated with a rapid variation in phreatic interdune water level and the subsequent establishment of anoxic and reducing conditions.The occurrence of exceptionally preserved liverwort colonies coincides with the sedimentary record of,at least,three seismite levels in the oasis.Data gathered from the site suggests that the water table of the oasis was controlled by a combination of(i)a positive creation of accommodation space due to subsidence associated with movement on syn-sedimentary extensional faults,and(ii)the rise and fall of the oasis water table controlled by the oscillations of the groundwater system due to orbital changes which appear to drive the variability of the climate system.Rising groundwater levels flooded the oasis soil crusts and lead to the exceptional recurrent preservation of liverwort colonies at the oasis margins.Alternatively,considering the hypothesis of floating or riparian liverworts in the oasis pond waters,the fall in the level of the oasis water table placed the floating liverworts in contact with the oasis bottom sediments.This fall in the level o

关 键 词：OASIS CRETACEOUS LIVERWORTS COLONIES Extensional tectonics Solar cyclicity 

分 类 号：Q948[生物学—植物学] P534.53[天文地球—古生物学与地层学]