有壳变形虫(testate amoebae)是一种新的具有潜力的环境变化生物指标。对采集自长白山区哈泥(42°12′50″N,126°31′05″E)、金川(42°20′47″N,126°21′35″E)、赤池(42°03′16″N,128°03′22″E)和圆池(42°01′55″N,128°25′58″E)等4个泥炭地不同生境的75个有壳变形虫样品,采用冗余分析方法(RDA)研究有壳变形虫种类组合变化与7个环境变量的关系,所有采样点均以泥炭藓(Sphagnum)为优势植被。结果表明水位埋深(depth to watertable),pH值和泥炭湿度是影响长白山区泥炭地有壳变形虫种类变化的主要环境因子,显著性检验达到p<0.001的水平。这一结果与国外其他地区的研究结果相一致,这3个环境因子可以作为目标变量进行有壳变形虫-环境因子转换函数的构建。
[Objective] To study the germination characteristics of Hordeum brevisubulatum seeds in the Songnen Plains of China under different conditions and find out the optimum conditions for germination.[Method] A total of five variable temperatures including 15/25,20/30,15/30,20/25 and 15/20 °C,five concentrations of sodium chloride solutions including 0,75,85,95 and 105 mmol/L,and five concentrations of CS2 strain(the A values were 0,0.500 0,0.050 0,0.005 0 and 0.000 5,respectively) were studied by orthogonal experimental design.[Result] The germination rate,germination energy and germination index were significantly(P < 0.05) affected by the temperature and sodium chloride concentration,but rarely affected by the CS2 strain concentration.Moreover,the germination rate,germination potential and germination index were all decreased with the increasing of sodium chloride concentration.[Conclusion] The optimal germination conditions of Hordeum brevisubulatum are as follows:temperatures of 15/25 °C and 15/30 °C,0 mmol/L of sodium chloride concentration.
