摘要
介绍了固N蓝藻细胞的结构和主要功能:固N蓝藻细胞中含有的叶绿素a能够进行产氧型光合作用;其异形细胞(heterocyst)是进行固N的场所;细胞能分泌胞外多糖(EPS),EPS为多聚阴离子大分子,可与阳离子相互作用,它对Na+的吸附能影响外环境pH改变。从4个方面分析了固N蓝藻的耐盐机理:Na+/H+和Na+/H+-K+反向载体系统可以不断地将胞内Na+排出胞外;在盐胁迫情况下可以合成酸性化合物,从而降低土壤的pH值;积累或产生一些相溶性物质,维持细胞内外渗透压平衡;结合N的存在可以阻止过量Na+的积累,从而提高蓝细菌的耐盐性等。详细介绍了国内外固N蓝藻在盐碱土生态恢复中的研究进展,分析了固N蓝藻在盐碱地改良中的优势及应用潜力以及蓝藻生物菌肥的研究与应用。
The cell structure and function of nitrogen-fixing cyanophytes were introduced. Chlorophyll a （Chl a） in cyanophytes possesses the capability of aerogenic photosynthesis. The heterocysts are the location of nitrogen fixation. The cells of nitrogen-fixing cyanobacteria can secrete exopolysaccharide （EPS）, most of which are anion polymers and can interact with cations, EPS＇s adsorption of Na^＋ can affect pH of external environment. The mechanism of salt tolerance of cyanobacteria were analyzed from four aspects, which focused on Na^＋ removal out of the cells by Na^＋/H^＋ and Na^＋/H^＋-K^＋ anti-carrier transportation system; pH decrease due to the acid compounds formed under the salt stress; osmatic-pressure balance of cell membrane by some soluble substances accumulated or produced and the presence of combined nitrogen, etc. The progresses of the research and application of nitrogen-fixing cyanophytes in the bio-remediation of saline-alkaline soils were reviewed. The advantages and potential of nitrogen-fixing cyanophytes in the amelioration of saline soils as well as the research and application of cyanobacteria biofertilizers were also discussed.
出处
《土壤》
CAS
CSCD
北大核心
2008年第4期510-516,共7页
Soils
基金
黑龙江省杰出青年基金(JC-02-04)资助
关键词
固氮蓝藻
盐碱土生态修复
耐盐机理
Nitrogen-fixing cyanophytes, Amelioration of saline-alkaline soil, Mechanism of salt tolerance
