Phytolith Morphology And Available Silicon Content Variations In A Bamboo Forest Plant-soil System

Phytolith has been widely used in paleoclimate,paleoenvironment reconstruction and phytoarchaeology.The representation of phytolith will be biased after burial.Most studies on the taphonomy of phytolith are carried out in forest,grassland,alpine soil and sediments.Complex origin of phytolith in soils with multi-community vegetation distribution and difficulties in identifying signals for taphonomy.The relationship between soil phytoliths and plants under single vegetation is clear,which is conducive to quantitative analysis of conservation characteristics.Karst rocky soils are characterized by thin soil layer,unique origin and little influence from external sources.Study on phytolith of karst soils can fill the research gap in this area.Based on the distribution characteristics of available silicon in plant-soil system of Dendrocalamus ronganensis,this study analyzed the combination and size of phytoliths in the plant-soil system.(1)There were differences in phytolith content and morphological combination among organs.The phytolith content variation trend of bamboo tissues was O-Layer > old leaves >new leaves> branch > culm,and phytolith content variation trend of soils was A-Layer > ABLayer.A total of 13 phytoliths were found in Dendrocalamus ronganensis.The content of GSSCP in bamboo leaves was high,dominated by BILOBATE(BILOBATE/SADDLE)and SADDLE,with high content of ELONGATEs in branches and culms.(2)The phytolith morphotype assemblage of soil and bamboo leaves is significantly correlated,and the phytolith assemblages of soil and bamboo leaves are mainly of BILOBATE(BILOBATE/SADDLE)and SADDLE.(3)There is still difference of phytolith assemblage between soil and plant tissue,and it is found that great difference between different phytolith morphotype after calculating representative index.The GSSCP were well preserved,and the size of SADDLE did not change significantly between plant and soil,indicating that was stable during burial.SILICA STOMA and ACUTE BULBOSUS gradually disappeared in humus and soil,indicating that it was not easily preserved.Besides soil properties,phytolith preservation may be related to its morphotype and chemical composition.(4)The distribution trend of available silicon content among samples was: O-Layer,ALayer and AB-Layer>new leaves>fallen leaves>branches>culms.Comparing the variation of available silicon content and phytoliths between samples,the high content of available silicon in soil indicated the supplementation with highly soluble biogenic silica.When the content of available silicon is high,it promotes the uptake and use of more silicon by plants and precipitate more phytolith under transpiration.