Life Sciences College of Fujian Agriculture and Forestry University, Fujian, 350002, China.
Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
Sci Rep. 2017 Jul 27;7(1):6691. doi: 10.1038/s41598-017-06768-x.
This study examined the hypotheses that soil microbial community composition and catabolic activity would significantly degenerated by consecutive monoculture in Chinese fir plantations. The phospholipid fatty acids (PLFA) and community level physiological profiles (CLPP) methods were used to assess the variations of soil microbial community among the first rotation Chinese fir plantation (FCP), the second rotation plantation (SCP) and the third rotation plantation (TCP). The total content of PLFA biomarkers was highest in FCP, followed by SCP, and TCP was the least detected. Conversely, the fungi/bacteria ratio significantly increased in the SCP and TCP soils. The average well-color development (AWCD) values significantly decreased (FCP > SCP > TCP). However, the sum of AWCD values of amino acids, carboxylic acids and phenolic compounds were higher significantly in the SCP and TCP soils than FCP soils, suggesting that the microflora feeding on acids gradually became predominant in the continuous monoculture plantation soils. Soil C/N ratio was one of the most important factors to soil microbial diversity. Both the PLFA and CLPP results illustrated the long-term pure plantation pattern exacerbated the microecological imbalance in the rhizospheric soils of Chinese fir, and markedly decreased the soil microbial community diversity and metabolic activity.
在连续的人工林单一种植模式下，土壤微生物群落组成和代谢活性会显著退化。采用磷脂脂肪酸（PLFA）和群落水平生理图谱（CLPP）方法评估了第一、二、三代杉木人工林（FCP、SCP 和 TCP）根际土壤微生物群落的变化。FCP 中 PLFA 生物标志物的总含量最高，其次是 SCP，而 TCP 检测到的含量最少。相反，SCP 和 TCP 土壤中的真菌/细菌比值显著增加。平均好氧颜色发展（AWCD）值显著降低（FCP>SCP>TCP）。然而，SCP 和 TCP 土壤中氨基酸、羧酸和酚类化合物的 AWCD 值总和明显高于 FCP 土壤，表明在连续的单一种植模式下，以酸为食的微生物逐渐占据主导地位。土壤 C/N 比是影响土壤微生物多样性的最重要因素之一。PLFA 和 CLPP 的结果都表明，长期的纯人工林种植模式加剧了杉木根际土壤的微生态失衡，显著降低了土壤微生物群落的多样性和代谢活性。
