马尾松飞播林地土壤微生物的研究

Study of Soil Microorganisms in Air-sowing Pinus massoniana Stands

为了探讨湘南丘陵低山区马尾松飞播林地土壤微生物的分布规律和土壤肥力综合评价方法 ,于 2 0 0 0年 12月 2 0日采集到湖南醴陵市大林乡 5个马尾松飞播林标准林地土壤样品和 1个阔叶林地土壤样品 ,分析其土壤微生物的数量及其类群分布规律 .结果表明 :马尾松飞播林地土壤微生物数量 (以干土计 )主要集中在 0～ 2 0 cm的表土层中 ,随土层加深 ,其数量迅速减少 ;在深度为 0～ 60 cm的土层中 ,同一类群的微生物数量变动范围较大 ,其中好气性细菌为 2 .46× 10 5～ 6.48× 10 5个 /g,厌气性细菌为 1.14× 10 3～ 8.8× 10 3个 /g,自生固氮菌为 1.3× 10 2～ 3 .0 1× 10 4个 /g,放线菌为 8.6× 10 3～ 2 .99× 10 4个 /g,真菌为 6.6× 10 3～ 2 .43 5× 10 5个 /g.其中 1号样地微生物数量最多 ,达 2 .45× 10 6个 /g。

To find out a synthetic way to evaluate the soil fertility of air sowing Pinus massoniana stands in lower mountainous areas of the southern part of Hunan Province, some researches were conducted on the amount and group distribution of air sowing Pinus massoniana stands in LiLing City on December 20,2000. The results show that soil microorganisms there are mainly concentrated in the 0～20 cm soil layer and their quantity rapidly decreases with the increase of soil depth; that the number of soil microorganisms of the same group varies greatly in soil within 0～60 cm depth, in which aerobic bacteria is 2.46×10 5～6.48×10 5 cell·g -1 , anaerobe is 1.143×10～8.8×10 4 cell·g -1 , nitrogen fixing bacteria is 1.3×10 2～3.01×10 4 cell·g -1 , Actinomyces is 8.6×10 3～2.99×10 4 cell.g -1 ,and fungi is 6.6×10 3～2.435×10 5 cell·g -1 ; and that the quantity of soil microorganisms in No.1 is the largest, which amounts to 2.45×10 6 cell·g -1 .