黄河口湿地土壤中生物硅的分布与植硅体的形态特征  

Distribution of Biogenic Silica and Composition of Phytolith in the Yellow River Estuary Wetland

作　　者：刘森[1] 冉祥滨[1] 车宏[1] 马永星[1,2] 臧家业[1] 

机构地区：[1]国家海洋局第一海洋研究所海洋生态研究中心,山东青岛266061 [2]青岛大学化学化工与环境学院,山东青岛266071

出　　处：《土壤》2014年第5期886-893,共8页Soils

基　　金：国家自然科学基金项目(41106072);山东省自然科学基金项目(ZR2010DM006);中央级公益性科研院所基本科研业务费专项资金项目(GY02-2012G29)资助

摘　　要：硅是地壳中重要元素之一,深刻影响着地表物质循环。湿地是全球碳、硅循环和气候变化研究的重要组成部分,然而针对湿地硅循环方面的研究较少。本文分别运用化学提取法和无损提取法,得出了黄河口三角洲湿地地表土壤中生物硅的含量、组成,并对湿地硅的分布特征与影响因素进行了研究。结果发现：黄河口湿地生物硅含量介于2.48~19.3 g/kg之间,并具有冬季高、秋季低的特点;生物硅与颗粒有机碳和颗粒有机氮含量具有显著的正相关关系,表明三者具有相似的来源;生物硅和植物可利用硅之间显著的相关性表明生物硅在土壤硅循环中起着主要作用。土壤中生物硅的含量与距离河道和海岸的长度均呈负相关关系,在生物硅的“距离效应”中海洋的作用较为显著。湿地表层土壤中植硅体的形态丰富,在黄河沿岸分别以哑铃形或突起棒形为主要植硅体形态,这与其植被特点有关;在II区域则主要以平滑棒形为主,且硅藻对生物硅的贡献比例明显增加。I区大部分站位发现的硅藻为圆筛藻,而在II区发现的硅藻主要为月形藻和舟形藻（羽纹硅藻纲）,这与湿地水陆相互作用有关。植硅体主要来源于本地植物,是土壤中生物硅的最主要贡献者,同时黄河泥沙携带的来自上游流域的植硅体也对湿地生物硅含量和组成有一定的贡献。黄河口湿地土壤中生物硅的含量和组成受到河流和海洋的共同影响,具有一定的区域特性,并可能对河流和海洋硅循环产生重大影响。Silicon is crucial in numerous biochemical and geochemical processes, its cycle is a hot issue of global environmental change and also an important area of marine science. Despite the importance of silicon, less knowledge is available on wetland silicon cycle. Base on the investigation in Yellow River estuary wetland in January of 2011 and October of 2012, distributions and sources of biogenic silica （BSi） were discussed. The results showed that： BSi in soil ranged from 2.48 to 19.3 g/kg, a significant linear relationship was found between BSi and particle organic carbon （POC） and particle organic nitrogen （PON）, which indicated their sources were same to some extent. Phytoliths were very rich in surface sediment, with forms of spiny bar, bar, pie, short saddle, corrugated shape, triangle, dumb-bell shape, etc. Spiny bar and dumb-bell shape were main forms of phytolith in I area of the Yellow River estuary wetland. While smooth bar model was the dominant form in II area. In this study, BSi in sediment was composed by diatoms and phytolith. As a small amount in the BSi, part of phytolith in I area came from the basin of Huanghe River transferred by river. While in II area, most of phytolith came from sediment of the Huanghe River deposited before the Yellow River diversion. Phytolith is co-affacted by river and ocean and may influence the silicon cycle in Huanghe River and Bohai Sea.

关 键 词：黄河口湿地 生物硅 植硅体 

分 类 号：S153.6[农业科学—土壤学] P343.5[农业科学—农业基础科学]