岷江干旱河谷辐射松人工林土壤微生物数量的季节动态

研究岷江干旱河谷不同造林时间辐射松(Pinus radiata D.Don)人工林土壤细菌(Bacteria)、放线菌(Actino-mycete)和真菌(Fungi)三类微生物数量的季节动态变化。结果表明:三大类土壤微生物区系中,细菌数量占优势,放线菌数量次之,真菌数量最少;三类微生物均有明显的季节变化,微生物数量秋季最高,夏季最少。茂县小庙山造林地土壤微生物总数最多,土壤肥力较其他林地高;理县薛城马山造林地的微生物总数最少,土壤肥力最低;总的来说,随着林龄的增加,辐射松人工林土壤肥力有增加的趋势。

Seasonal Dynamic State of Soil Microbial Counts beneath Pinus radiata Plantation in the Dry Valley of the Minjiang River

Seasonal dynamic state of soil microbial counts were studied to understand the changes in soil fertility beneath the Pinus radiata D.Don plantations of the dry valley of the Minjiang river.Regardless of the forest sites and sampling time,microbial counts in soils showed the ranked order of bateria>actinomycetes>fungi.Significant seasonal fluctuation was found in soil microbial counts with the maximum in autumn and the minimum in summer.Soil fertility,indicated by total microbial counts,was the highest in the plantation of Xiaomiao mountain,Mao county,while the lowest soil fertility was found in the plantation of Ma mountain of Li county.On the whole,soil fertility beneath the Pinus radiata plantation increased with the forest stand age.