岷江上游毛榛、辽东栎灌丛及3种人工幼林土壤种子库的比较

本文采用野外调查与萌发实验相结合的方法对岷江上游地区自然恢复的灌丛以及 3种人工林的土壤种子库状况进行了比较研究。结果显示 ,各样地土壤种子库的储量为 192 5 0～ 3 13 60粒 /(m2 × 10cm)之间 ,人工林的土壤种子库储量和物种数量都大于自然恢复的灌丛 ,其顺序为连香树Cercidiphyllum japonicum、油松Pinustabulaeformis混交林 >连香树林 >油松林 >毛榛Corylusmandshurica、辽东栎Quercusliaotungensis灌丛 ,各样地土壤种子库密度的垂直分布均为上层 >中层 >下层。在各样地土壤种子库的生活型组成中 ,乔木种类所占比例极少 ,而草本种类的数量较多。在灌丛的土壤种子库中 ,灌木的物种数量及其在种子库中所占的比例均大于人工林。大序醉鱼草Buddlejamacrostachya、喜阴悬钩子Rubusmesogaeus、华西绣线菊Spiraealaeta在种子库中的大量存在明显提高了灌木在各样地土壤种子库中所占的比例

A Comparison in the Soil Seed Banks of a Corylus Mandshurica-Quercus Liaotungensis Mixed Scrub Community and Three Young Forest Plantations in the Upper Reach of Minjiang River

As a preliminary study of the soil seed banks in the upper r ea ch of Minjiang River,this paper examined the soil seed banks of three forest pl antations and a Corylus mandshurica Quercus liaotungensis mixed scrub community based on the field observation and germination trial in Dagou Basin,Maoxian C ounty,NW Sichuan The results showed that the seed densities in the soil seed b anks of 4 communities were between 19 250 and 31 360 seeds m -2 in the top soil of 10 cm Both the numbers of the individual and species of seeds in the so il seed bank of the three forest plantations were higher than those of the scrub community The seed densities decreased with soil depth in all four communities The seedsof grass and herb species dominated the soil seed banks,but tree see ds were rare in the soil seed banks under all four communities The percentage o f seeds of shrub species in the soil seed banks of the scrub community was highe r than those of the forest plantations The proportions of scrub were highly inc reased as the large storage of seeds of Buddleja macrostachya?Rubus mesogaeus and Spiraea rosthornii in the soil seed banks of all 4 communities