桉树人工林土壤种子库研究

为了了解桉树人工林土壤种子库的物种组成、密度、垂直分布等特征，以2年生桉树人工林为研究对象，相邻的大叶栎人工林作对照，取其土壤，通过室内种子萌发的方法，研究桉树人工林土壤种子库分布特征。结果表明：（1）各土壤层种子萌发的规律基本一致，大约从第7天开始进入种子萌发高峰期，第19天萌发高峰期基本结束，随后进入缓慢萌发期，至最后停止萌发；（2）桉树人工林土壤种子库储量较大，种子密度为9804粒/m2（对照为3614粒/m2），共计物种15种，分属于9科，其中禾本科的弓果黍为优势种，种子密度为8849粒/m2，占土壤种子库总量90.26%；（3）种子库垂直分布格局显示，80%以上的种子储存在枯枝落叶层和0~5 cm的土壤中。2年生桉树人工林土壤种子库的种子密度大于大叶栎人工林，其组成以草本为主，灌木次之，种子多集中在枯枝落叶层和浅层土壤中。

The Study on the Soil Seed Bank of Eucalyptus Plantation

In order to investigate the species composition, density and vertical distribution characteristics of the soil seed bank of Eucalyptus plantation, the growth of 2-year-old Eucalyptus plantation was researched in comparison with the nearby miscellaneous wood. Through the method of the interior of seed germination and taking their forest soil, the distribution characteristics of Eucalyptus plantation soil seed bank were studied. The results showed that： （1） the rate of seed germination was about the same rule from 7 days beginning to enter seed germination peak, 19 days to an end, then germination peak into the slow development to finally stop germination; （2） Eucalyptus plantation＇ s soil seed banks and seed density largely reserved for 9804 grain/ms （control for 3614 grain/mS）, a total of 15 species, belonging to 9 families, of which the Gramineae cyrtococcum as the dominant species with an seed density of 8849 grain/m2, accounting for 90.26% of total soil seed bank; （3） Seed bank vertical distribution pattern showed that more than 80% of the seeds stored in dead branches of leaves and 0-5 cm of soil. The density characteristics of the soil seed bank of Eucalyptus plantation were larger than the miscellaneous wood, which were mainly the branches of leaves and the surface soils. herb and next to the shrub. The seed stored mostly in dead