干旱区生态环境知识资源中心(Arid): 微鞘藻胞外多糖在沙漠土壤成土中的作用

Arid

	微鞘藻胞外多糖在沙漠土壤成土中的作用
其他题名	The function of exopolysaccharides of microcoleus in the formation of desert soil
	陈兰周; 刘永定; 宋立荣
来源期刊	水生生物学报
ISSN	1000-3207
出版年	2002
卷号	26 期号:2 页码:155-159
中文摘要	研究了沙坡藻结皮中的优势物种－微鞘藻的胞外多糖对沙漠表层土壤分分布状况的影响及其光合特性。随胞外多糖浓度的升高，土壤持水量增大，土壤水分蒸发速率降低，水分在土壤中运动的速率被延缓。藻总水溶性多糖产率为28.82％，胞外水溶性多糖产率为16.09％；多糖产量在稳定期生物量最大时增长最快。微鞘藻光合作用最适温度为25℃，最适光强为400muE·m~(-2)·s~(-1)，在0.3mol/L NaCl浓度下其光合作用活性被强烈抑制；微鞘藻的吸收光谱表明它比生长在湿润地区的藻类含有更多的胡萝卜成分；叶绿素a荧光（Fv/Fm）分析表明在失水约为实绍湿重的56％时Fv/Fm值恢复到水培养的96％；其光合作用特性有利于对逆境的适应和生物量的积累。表明微鞘藻胞外多糖可影响沙漠表层土壤水分分布状况，并可作为一种潜在的生物肥料，在荒漠原始成土过程中扮演着重要角色。
英文摘要	The present work deals with the exopolysaccharides (EPS) and photosynthetic activities of Microcoleus.vaginatus (one of the pioneer species in algal crusts at Shapotou, Linxia). With the concentration of EPS increasing, water-holding capacity of desert soil was increasing, water evaporation was decreasing, and water movement through the desert soil was retarded. The yield of exopolysaccharides was 28.82% of dry weight, and reached the maximum during the stationary phase. Mirocoleus had more carotenoid contents than other misted cells in view of its absorption spectrum; the most optimum temperature for photosynthesis was about 25℃, the most optimum light intensity for photosynthesis was 400muEm~(-2)·s~(-1), and photosynthetic activity was inhibited strongly after 0.3mol/l of NaCl; the value of Chlorophyll a fluorescence (Fv/Fm) recovered 96% of cultures after losing water to 56% of fresh weight. It indicated that Microcoleus influenced the hydrological properties and played an important role in desert soil formation.
中文关键词	藻结皮 ; 胞外多糖 ; 成土作用 ; 水分分布状况 ; 光合活性
英文关键词	algae crust exopolysaccharide (EPS) soil formation hydrological property photosynthetic activity
语种	中文
国家	中国
收录类别	CSCD
WOS类目	PLANT SCIENCES
WOS研究方向	Plant Sciences
CSCD记录号	CSCD:1142072
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/203428
作者单位	中国科学院水生生物研究所, 武汉, 湖北 430072, 中国
推荐引用方式 GB/T 7714	陈兰周,刘永定,宋立荣. 微鞘藻胞外多糖在沙漠土壤成土中的作用[J],2002,26(2):155-159.
APA	陈兰周,刘永定,&宋立荣.(2002).微鞘藻胞外多糖在沙漠土壤成土中的作用.水生生物学报,26(2),155-159.
MLA	陈兰周,et al."微鞘藻胞外多糖在沙漠土壤成土中的作用".水生生物学报 26.2(2002):155-159.