凋落物和根系去除对滨海沙地土壤微生物群落组成和功能的影响

发布时间：2018-10-31 12:14

【摘要】：通过在亚热带滨海防护林湿地松、尾巨桉、纹荚相思和木麻黄人工林中设置去除凋落物、去除根系和对照处理,分析改变地上、地下碳输入对沙地人工林土壤微生物生物量、群落结构和功能的影响.2015年9月,在处理设置一年后采集各处理样方0~10 cm土壤样品,分别采用磷脂脂肪酸分析方法和微孔板酶检测技术对土壤样品的微生物群落组成和6种酶活性进行测定.结果表明:碳输入处理对土壤微生物生物量的影响因树种而异,并主要取决于凋落物和根系的质量.在尾巨桉林中,去除根系使得脂肪酸总量、革兰氏阳性细菌、革兰氏阴性细菌、真菌和放线菌生物量分别显著减少了31%、30%、32%、36%和26%,去除凋落物使得革兰氏阳性细菌、真菌和放线菌生物量显著减少了24%、27%和24%,而其他树种处理对微生物生物量无显著影响.碳输入处理对土壤微生物群落结构的影响主要表现为真菌丰度下降而放线菌丰度上升.不同树种的土壤酶活性对处理的响应表现不一致:湿地松、纹荚相思和木麻黄林分去除凋落物显著降低土壤中纤维素水解酶、β-葡萄糖苷酶、酸性磷酸酶和乙酰氨基葡萄糖苷酶活性,去除根系仅分别降低和提高了湿地松和纹荚相思林β-葡萄糖苷酶的活性;湿地松、木麻黄人工林去除凋落物显著降低了多酚氧化酶和过氧化物酶活性;去除根系对所有树种土壤氧化酶活性影响不显著.不同树种的凋落物、根系特性是影响土壤微生物群落组成和酶活性的重要因子,碳输入处理造成的土壤温度、水分等微环境的改变也是土壤微生物性质变化的重要驱动力.
[Abstract]:Through setting up litter removal, root removal and control treatment in Pinus elliottii, Eucalyptus grandis, Acacia acacia and Casuarina equisetifolia plantation in subtropical coastal shelter forest, the soil microbial biomass of sandy plantation was analyzed by changing the ground and underground carbon input. The effect of community structure and function. In September 2015, soil samples of 0 ~ 10 cm were collected from each treatment sample one year after the treatment was set up. The microbial community composition and the activities of 6 enzymes in soil samples were determined by phospholipid fatty acid analysis and microplate enzyme detection. The results showed that the effect of carbon input treatment on soil microbial biomass varied with tree species and mainly depended on the quality of litter and root system. In Eucalyptus grandis forest, the total fatty acids, gram-positive bacteria, gram-negative bacteria, fungi and actinomycetes were significantly reduced by 313032% and 26%, respectively. Removal of litter significantly reduced the biomass of Gram-positive bacteria, fungi and actinomycetes by 24% and 24%, while the treatment of other species had no significant effect on microbial biomass. The effect of carbon input treatment on soil microbial community structure mainly showed that the abundance of fungi decreased and the abundance of actinomycetes increased. The soil enzyme activity of different tree species showed different responses to the treatments: Pinus elliottii, Acacia acacia and Casuarina equisetifolia stand to remove litter significantly reduced soil cellulose hydrolase, 尾-glucosidase, 尾-glucosidase. The activities of acid phosphatase and acetyl glucosaminidase were decreased and increased only by removing root system of Pinus elliottii and Acacia acacia Linn. The removal of litter from Pinus elliottii and Casuarina equisetifolia plantation significantly reduced the activities of polyphenol oxidase and peroxidase, but the removal of roots had no significant effect on the soil oxidase activity of all tree species. The root characteristics of different tree species are important factors affecting soil microbial community composition and enzyme activity. The changes of soil temperature and water caused by carbon input are also important driving forces of soil microbial properties change.
【作者单位】：湿润亚热带山地生态国家重点实验室培育基地;福建师范大学地理科学学院;福建省长乐大鹤国有防护林场;
【基金】：国家自然科学基金项目(41371269,31570604) 国家重点基础研究发展计划项目(2014CB954003)资助~~
【分类号】：S714

【相似文献】