消落带湿地土壤苍耳种子库研究

为了解三峡水库三期蓄水后消落带新生湿地苍耳种子库,于2010年4月对澎溪河消落带湿地进行了调查.结果表明:(1)土壤表层(0～5cm)种子密度、萌发率及萌发数量均随海拔升高而增加.(2)种子密度介于490.33～1 191.83颗/m2之间,萌发率从0.20%到18.45%,萌发数量为1～214颗/m2.(3)多重比较检验显示,无论植物群落类型还是水位梯度上种子密度、萌发率和萌发数量差异均不显著(p＞0.05).(4)相关分析表明,萌发率、萌发数量与群落类型显著相关(p＜0.05),种子密度与植物群落类型极相关(p＜0.01);萌发数量与水位梯度相关性极显著(p＜0.01),但萌发率、种子密度与其不相关(p＞0.05).三峡水库水位周期性变动下,苍耳种子空间分布格局发生改变,种子在消落带范围内的分布趋于均质,同时由于微生境的异质性而产生一些差异.

Soil Seed Bank of Xanthum sibircum in Newly Created Wetlands in Water-Level Fluctuation Zone of Three Gorges Reservoir

In April 2010,an investigation was made to study the X.sibircum dynamics of soil seed bank in water-level fluctuation zone of the newly created wetlands-Three Gorges Reservoir after flooding to 173 m height.The following results have been obtained:(1)The germination rate,germination amount and the seed density in soil surface(0~5 cm)increased with altitude.(2)The density ranged from 490.11 to 1 191.83 grain/m2,while the germination rate went from 0.20% to 18.45% and germination amount was between 1 to 214 g...