摘要:
采用Biolog-ECO微平板检测法，以21、30、40和52年生落叶松人工林土壤为对象，研究了典型黑土区0～20 cm土层范围内土壤微生物群落碳源代谢的多样性变化特征。结果表明：1）在培养168 h时，落叶松人工林地上层（0～10 cm）和下层（10～20 cm）土壤的微生物碳源平均颜色变化率（AWCD）的变化范围分别为0.41～1.40和0.20～0.69，且均随林龄的增加而逐渐增大。2）落叶松人工林微生物群落功能多样性指数随林龄的增加呈逐渐升高的趋势，即52 a40 a30 a21 a，且上层土壤的微生物功能多样性高于下层。上层和下层土壤的丰富度指数、ShannonWeiner多样性指数、Simpson指数和McIntosh指数的变化范围分别为12～25和6～14、2.55～3.12和1.83～2.62、0.89～0.95和0.76～0.91、4.22～9.49和2.52～6.18。3）落叶松人工林土壤微生物群落对6类碳源的利用率均随林龄的增加而增大，且碳水类、多聚物类和胺类是导致上层土壤微生物代谢差异的敏感碳源，碳水类、羧酸类和胺类是导致下层土壤微生物代谢差异的敏感碳源。4）落叶松人工林土壤微生物多样性指标与土壤理化性质相关性极为密切。可以认为，随着林龄的增加，落叶松人工林微生物功能多样性逐渐提高，这为进一步揭示其林地土壤质量的演变提供了参考。
Abstract:
Metabolism diversity of soil microbial carbon sources of surface soil (0-20 cm) from 21, 30, 40, and 52-year-old larch (Larix gmelini) plantations in typical black soil region of northeastern China was studied by using the method of Biolog-ECO microplate culture. Results showed that the average well color development (AWCD) increased gradually with forest age increasing, varying from 0.41 to 1.40 and 0.20 to 0.69 (cultured for 168 hrs) for 0-10 cm and 10-20 cm soil depth, respectively. The peak value of microbial functional diversity was found in 52-year-old plantations, followed by 40, 30, 21-year-old in consequence. The microbial functional diversity indices in shallower soil depth all showed higher values: for soil in 0-10 cm and 10-20 cm depth, richness index was 12-25 and 6-14, ShannonWeiner diversity index was 2.55-3.12 and 1.83-2.62, Simpson diversity index was 0.89-0.95 and 0.76-0.91, McIntosh index was 4.22-9.49 and 2.52-6.18, respectively. The utilization efficiency of six carbon sources by the soil microbial community also increased when plantations grew from 21 to 52-year-old. Sensitive carbon sources to cause microbial metabolic differences were carbohydrates, polymers and amines for soil of 0-10 cm, and carboxylic acids in addition to carbohydrates and amines for 10-20 cm also. The significant relationships were observed between the metabolic diversity of microbial communities and soil physical and chemical properties. We conclude that functional diversity of soil microbial community in larch plantations increases gradually with the increase of forest age, and soil microbial functional diversity can be improved by implementing plantation vegetations recovery. The results presented in this paper could further suggest a reference for revealing transmutation of soil quality under plantations of black soil region, northeastern China.
百度学术
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