Phosphorus fractions, microbial biomass and enzyme activities in some alkaline calcareous subtropical soils

The relationship between microbial biomass and enzyme activities under heavy metal pollution had attracted much attention in ecology. The experimental sediment samples were supplemented with Pb and Cr and incubated at room temperature for a month. Microbial properties such as microbial biomass, urease, catalase and cellulase activities, together with several chemical properties such as pH, total organic carbon , oxidation-reduction potential, total nitrogen and phosphorus were measured to evaluate changes in sediment qualities. Our results demonstrate that heavy metals would inhibit sediment microbe biomass and enzyme activities. Such decreases in sediments microbial biomass and enzyme activities by Pb and Cr contamination may help to evaluate heavy metals contaminated soil ecologies.

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Differences of soil enzyme activities and its influencing factors under different flooding conditions in Ili Valley, Xinjiang

PeerJ ◽

10.7717/peerj.8531 ◽

2020 ◽

Vol 8 ◽

pp. e8531 ◽

Cited By ~ 1

Author(s):

Yulu Zhang ◽

Dong Cui ◽

Haijun Yang ◽

Nijat Kasim

Keyword(s):

Microbial Biomass ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Total Phosphorus ◽

Enzyme Activities ◽

Catalase Activity ◽

Microbial Biomass Carbon ◽

Chemical Properties ◽

Soil Enzyme ◽

Biomass Carbon

Background A wetland is a special ecosystem formed by the interaction of land and water. The moisture content variation will greatly affect the function and structure of the wetland internal system. Method In this paper, three kinds of wetlands with different flooding levels (Phragmites australis wetland (long-term flooding), Calamagrostis epigeios wetland(seasonal flooding) and Ditch millet wetland (rarely flooded)) in Ili Valley of Xinjiang China were selected as research areas. The changes of microbial biomass carbon, soil physical and chemical properties in wetlands were compared, and redundancy analysis was used to analyze the correlation between soil physical and chemical properties, microbial biomass carbon and enzyme activities (soil sucrase, catalase, amylase and urease). The differences of soil enzyme activities and its influencing factors under different flooding conditions in Ili Valley were studied and discussed. Result The results of this study were the following: (1) The activities of sucrase and amylase in rarely flooded wetlands and seasonally flooded wetlands were significantly higher than those in long-term flooded wetlands; the difference of catalase activity in seasonal flooded wetland was significant and the highest. (2) Redundancy analysis showed that soil organic carbon, dissolved organic carbon, total phosphorus and soil microbial biomass carbon had significant effects on soil enzyme activity (p < 0.05). (3) The correlation between soil organic carbon and the sucrase activity, total phosphorus and the catalase activity was the strongest; while soil organic carbon has a significant positive correlation with invertase, urease and amylase activity, with a slight influence on catalase activity. The results of this study showed that the content of organic carbon, total phosphorus and other soil fertility factors in the soil would be increased and the enzyme activity would be enhanced if the flooding degree was changed properly.

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