Microbial biomass C and N, and respiratory activity in soil of repeatedly limed and N-and P-fertilized Norway spruce stands

• Published in: Soil biology & biochemistry 1994, Vol.26 (8), p.957-962
• Main Authors: Smolander, A., Kurka, A., Kitunen, V., Mälkönen, E.
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biochemistry and biology; Biological and medical sciences; Chemical, physicochemical, biochemical and biological properties; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Generalities. Analysis and diagnosis methods; Microbiology; Physics, chemistry, biochemistry and biology of agricultural and forest soils; Picea abies; Soil science; Soil-plant relationships. Soil fertility. Fertilization. Amendments
• ISSN: 0038-0717; 1879-3428
• DOI: 10.1016/0038-0717(94)90109-0

Our aim was to assess long-term effects of repeated liming and N and P additions on soil microbial biomass and activity. The experimental sites were four, 40–60 yr old, Norway spruce ( Picea abies L.) stands growing on mineral soil sites. During the 30 yr study period, the cumulative amount of finely-ground limestone totalled 6000 kg ha −1, and fertilizer N and P totalled 530–950 and 70–115 kg ha −1, respectively. The main effects of the additions, expressed on an organic matter basis, were as follows: liming increased, and N addition decreased, both the fumigation-extraction (FE) and substrate-induced-respiration (SIR) derived microbial biomass C, microbial biomass N and its proportion of total soil N, and microbial respiration rate. Nitrogen addition increased slightly the soil ergosterol content, indicating an increase in fungal biomass or a change in fungal population structure. There were no significant differences in microbial C:N ratio and respiration: biomass ratio between the treatments. No clear effects of P addition were observed.