植被类型对亚高山森林土壤微生物生物量碳氮的影响。

Effects of vegetation type on microbial biomass carbon and nitrogen in subalpine mountain forest soils.

机构信息

Department of Food Science, China University of Science and Technology, Nankang, Taipei, Taiwan; Department of Biochemical Science and Technology, National Taiwan University, Taipei, Taiwan.

出版信息

J Microbiol Immunol Infect. 2015 Aug;48(4):362-9. doi: 10.1016/j.jmii.2014.02.003. Epub 2014 Mar 21.

DOI:10.1016/j.jmii.2014.02.003

PMID:24662014

Abstract

BACKGROUND/PURPOSE: Microbial biomass plays an important role in nutrient transformation and conservation of forest and grassland ecosystems. The objective of this study was to determine the microbial biomass among three vegetation types in subalpine mountain forest soils of Taiwan.

METHODS

Tatachia is a typical high-altitude subalpine temperate forest ecosystem in Taiwan with an elevation of 1800-3952 m and consists of three vegetation types: spruce, hemlock, and grassland. Three plots were selected in each vegetation type. Soil samples were collected from the organic layer, topsoil, and subsoil. Microbial biomass carbon (Cmic) was determined by the chloroform fumigation-extraction method, and microbial biomass nitrogen (Nmic) was determined from the total nitrogen (Ntot) released during fumigation-extraction. Bacteria, actinomycetes, fungi, cellulolytic microbes, phosphate-solubilizing microbes, and nitrogen-fixing microbes were also counted.

RESULTS

The Cmic and Nmic were highest in the surface soil and declined with the soil depth. These were also highest in spruce soils, followed by in hemlock soils, and were lowest in grassland soils. Cmic and Nmic had the highest values in the spring season and the lowest values in the winter season. Cmic and Nmic had significantly positive correlations with total organic carbon (Corg) and Ntot. Contributions of Cmic and Nmic, respectively, to Corg and Ntot indicated that the microbial biomass was immobilized more in spruce and hemlock soils than in grassland soils. Microbial populations of the tested vegetation types decreased with increasing soil depth.

CONCLUSION

Cmic and Nmic were high in the organic layer and decreased with the depth of layers. These values were higher for spruce and hemlock soils than for grassland soils. Positive correlations were observed between Cmic and Nmic and between Corg and Ntot.

摘要

背景/目的：微生物生物量在森林和草原生态系统的养分转化和保护中起着重要作用。本研究的目的是确定台湾亚高山森林土壤中三种植被类型的微生物生物量。

方法

塔塔西亚是台湾典型的高海拔亚高山温带森林生态系统，海拔 1800-3952 米，由三种植被类型组成：云杉、铁杉和草原。在每种植被类型中选择三个样地。从有机层、表土层和底土层采集土壤样本。采用氯仿熏蒸-提取法测定微生物生物量碳（Cmic），从熏蒸-提取过程中释放的总氮（Ntot）中测定微生物生物量氮（Nmic）。还计数了细菌、放线菌、真菌、纤维素分解菌、解磷菌和固氮菌。

结果

Cmic 和 Nmic 在表土中最高，随土壤深度下降。云杉土壤中最高，铁杉土壤次之，草原土壤中最低。Cmic 和 Nmic 在春季最高，冬季最低。Cmic 和 Nmic 与总有机碳（Corg）和 Ntot 呈显著正相关。Cmic 和 Nmic 对 Corg 和 Ntot 的贡献表明，微生物生物量在云杉和铁杉土壤中比在草原土壤中固定得更多。测试植被类型的微生物种群随土壤深度的增加而减少。