宁夏盐池荒漠草原土壤种子库动态变化研究

A study on dynamic changes of soil seed bank in desert steppe of Yanchi in Ningxia

研究宁夏盐池县荒漠草原牧草不同生长时期土壤种子库种子密度动态变化.结果表明牧草返青期,牧草生长发育期,牧草种子成熟期的种子库种子密度呈先下降后上升的动态变化.种子库种子平均发芽率为38.26%,且以单子叶种子数量居多,是双子叶数量的6.75倍.种子密度水平分布上以中坡和下坡较高,在垂直分布上随着土壤深度加深呈现减少的趋势.

The seed density dynamic changes of soil seed bank in different pasturage growth phase on the desert steppe of Yanchi, county Ningxia were studied. The result showed that the density of seed first decreased and then increased with the time of pasturage reviving, pasturage growing and seed maturing. The average germination rate of seed in the seed bank was 38.26%. The seed number of monocotyledon was higher than that of dicotyledonous, and the seed number of monocotyledon was 6.75 times for that of dicotyledonous. On the level distribution, the density of seed was higher in mesoslope and lowslope. On the vertical distribution, the number of seed took on a decreasing trend with the depth of soil increased.