Responses of Soil Microbial Biomass and Enzyme Activities to Tillage and Fertilization Systems in Soybean (Glycine max L.) Production

The aim of this study was to define a relationship between heavy metal (Cu, Mo) pollution of soil and various extracellular enzyme activities. Six enzymatic activities involved in cycles of carbon, nitrogen, phosphorus and sulfur (β-glucosidase, chitinase, leucine-aminopeptidase, acid phosphomonoesterase, alkaline phosphomonoesterase, and arylsulphatase) as well as microbial biomass were determined in soil samples collected in the surroundings of Zangezur Copper and Molybdenum Combine. The investigations showed that pollution of soil with copper and molybdenum led to a decrease in microbial biomass and soil enzymatic activity, which in turn had a negative impact on cycles of chemical elements, in particular C, P, N and S. This gives reason to conclude that the changes in soil microbial biomass and enzymatic activity may act as indicators of soil biological activity and quality.

Download Full-text

Age and Species of Eucalyptus Plantations Affect Soil Microbial Biomass and Enzymatic Activities

Microorganisms ◽

10.3390/microorganisms8060811 ◽

2020 ◽

Vol 8 (6) ◽

pp. 811 ◽

Cited By ~ 1

Author(s):

Jie Xu ◽

Bing Liu ◽

Zhao-lei Qu ◽

Yang Ma ◽

Hui Sun

Keyword(s):

Microbial Biomass ◽

Enzyme Activities ◽

Fungal Biomass ◽

Soil Microbial Biomass ◽

Extracellular Enzymes ◽

Eucalyptus Species ◽

Eucalyptus Plantation ◽

Soil Microbial ◽

Eucalyptus Plantations ◽

Plantation Age

Soil microorganisms and extracellular enzymes play important roles in soil nutrient cycling. Currently, China has the second-largest area of eucalyptus plantations in the world. Information on the effects of eucalyptus age and species of trees on soil microbial biomass and enzyme activities, however, is limited. In this paper, the soil microbial biomass and enzyme activities were studied in eucalyptus plantations with different ages (1 and 5+ years) and species of trees (E. urophylla×E. grandis, E. camaldulens and E. pellita) in South China. The results showed that both plantation age and eucalyptus species could affect the total microbial biomass and fungal biomass, whereas the bacterial biomass was affected only by plantation age. The fungal biomass and the fungi-to-bacteria ratio significantly increased along with increasing plantation age. Similarly, the plantation age and eucalyptus species significantly affected the enzyme activities associated with carbon cycling (β-xylosidase, β-d-glucuronidase, β-cellobiosidase and β-glucosidase). The activities of β-d-glucuronidase and β-glucosidase were significantly higher in the E. camaldulens plantation. The enzymes involved in nitrogen (N-acetyl-glucosamidase) and sulfur (sulfatase) cycling were only affected by the eucalyptus plantation age and species, respectively. The results highlight the importance of the age and species of eucalyptus plantations on soil microbial activities.

Download Full-text