title: Metabolic influence of psychrophilic diatoms on travertines at the Huanglong Natural Scenic District of China.
abstract: Diatoms are a highly diversified group of algae that are widely distributed in aquatic ecosystems, and various species have different nutrient and temperature requirements for optimal growth. Here, we describe unusual psychrophilic diatoms of Cymbella in a travertine deposition environment in southwestern China in winter season. Travertine surfaces are colonized by these psychrophilic diatoms, which form biofilms of extracellular polysaccharide substances (EPS) with active metabolic activities in extremely cold conditions. The travertine in Huanglong, is a typical single crystalline calcite with anisotropic lattice distortions of unit cell parameters along axes of a and c, and this structure is suggestive of some level of metabolic mediation on mineralization. Near-edge X-ray absorption fine structure spectroscopy (NEXAFS) results further confirmed the occurrence of biogenic distortion of the crystal lattice of travertine calcite. Overall, our results imply that the metabolic influence of psychrophilic diatoms may be particularly important for promoting formation and dissolution of travertine in extremely cold environments of Huanglong. The EPS of psychrophilic diatoms will protect travertine from HCO3- etching and provide template for forming travertine when water re-flowing, in warm season.
authors.affiliation: Department of Geological and Mineral Engineering, Key Laboratory of Solid Waste Treatment and Resource Recycle & Fundamental Science on Nuclear Waste and Environmental Security Laboratory, Southwest University of Science and Technology, Mianyang 621010, China. shysun@swust.edu.cn.
authors.forename: Shiyong
authors.initials: S
authors.lastname: Sun
authors.affiliation: Department of Geological and Mineral Engineering, Key Laboratory of Solid Waste Treatment and Resource Recycle & Fundamental Science on Nuclear Waste and Environmental Security Laboratory, Southwest University of Science and Technology, Mianyang 621010, China. fqdong@swust.edu.cn.
authors.forename: Faqin
authors.initials: F
authors.lastname: Dong
authors.affiliation: Institute of Experimental Physics, Technische Universität Bergakademie Freiberg, Freiberg 09599, Germany. hermann.ehrlich@physik.tu-freiberg.de.
authors.forename: Hermann
authors.initials: H
authors.lastname: Ehrlich
authors.affiliation: Department of Geological and Mineral Engineering, Key Laboratory of Solid Waste Treatment and Resource Recycle & Fundamental Science on Nuclear Waste and Environmental Security Laboratory, Southwest University of Science and Technology, Mianyang 621010, China. zxqch@sina.com.
authors.forename: Xueqing
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Department of Geological and Mineral Engineering, Key Laboratory of Solid Waste Treatment and Resource Recycle & Fundamental Science on Nuclear Waste and Environmental Security Laboratory, Southwest University of Science and Technology, Mianyang 621010, China. dragonlmx@126.com.
authors.forename: Mingxue
authors.initials: M
authors.lastname: Liu
authors.affiliation: Department of Geological and Mineral Engineering, Key Laboratory of Solid Waste Treatment and Resource Recycle & Fundamental Science on Nuclear Waste and Environmental Security Laboratory, Southwest University of Science and Technology, Mianyang 621010, China. qw_dai@163.com.
authors.forename: Qunwei
authors.initials: Q
authors.lastname: Dai
authors.affiliation: Department of Geological and Mineral Engineering, Key Laboratory of Solid Waste Treatment and Resource Recycle & Fundamental Science on Nuclear Waste and Environmental Security Laboratory, Southwest University of Science and Technology, Mianyang 621010, China. liqiongfang992605@126.com.
authors.forename: Qiongfang
authors.initials: Q
authors.lastname: Li
authors.affiliation: Huanglong National Scenic Resort Administrative Bureau, Songpan 623300, China. andejun.618hl@126.com.
authors.forename: Dejun
authors.initials: D
authors.lastname: An
authors.affiliation: Department of Geology and Environmental Earth Science, Miami University, Oxford, OH 45056, USA. dongh@miamioh.edu.
authors.forename: Hailiang
authors.initials: H
authors.lastname: Dong
mesh_terms: D018441:Biofilms; D002681:China; D003080:Cold Temperature; D017377:Diatoms / Q000502:physiology*; D005618:Fresh Water / Q000032:analysis*; D019015:Geologic Sediments / Q000737:chemistry*; D045482:Hot Springs / Q000737:chemistry; D012621:Seasons; D056928:X-Ray Absorption Spectroscopy