Abstract
A comprehensive understanding of how microbial associated with nitrogen (N) cycling respond to artificial vegetation restoration is still lacking, particularly in arid to semi-arid degraded ecosystems. We compared soil net N mineralization rates and the abundance of bacteria, archaea, and eleven N microbial genes on the northern Loess Plateau of China during the process of artificial vegetation restoration. The quantitative relationships between net N mineralization rates and N microbial genes were determined. We observed a significant difference of net transformation rates of NH4+-N (Ra), NO3−-N (Rd), and total mineralization (Rm), which rapidly decreased in 10-year soils and steadily increased in the 10–30-year soils. Different N functional microbial groups responded to artificial vegetation restoration distinctly and differentially, especially for denitrifying bacteria. Stepwise regression analysis suggested that Ra was collectively controlled by AOA-amoA and Archaea; Rd was jointly governed by narG, napA, nxrA, and bacreria; and Rm was jointly controlled by napA, narG, nirK, nirS, norB, nosZ, and nxrA.
Highlights
Artificial vegetation restoration is an effective way to improve soil conditions and to restore degraded ecosystems, especially in the degraded ecosystems of arid to semi-arid regions[1, 2]
The three genes, ammonia-oxidizing archaea (AOA-amoA), ammonia-oxidizing bacteria (AOB-amoA), and nitrite oxidoreductase, are three functional genes involved in the nitrification process (NH4+-N → NO2−-N → NO3−-N)[5]
Relatively few studies have focused on soil microbial properties and N functional microbes during the process of artificial vegetation restoration, and very little is known in regard to the fate of N processing and the underlying mechanism that governs the N transformation
Summary
Artificial vegetation restoration is an effective way to improve soil conditions and to restore degraded ecosystems, especially in the degraded ecosystems of arid to semi-arid regions[1, 2]. Relatively few studies have focused on soil microbial properties and N functional microbes during the process of artificial vegetation restoration, and very little is known in regard to the fate of N processing and the underlying mechanism that governs the N transformation. The effects of artificial afforestation on soil nutrient properties, bacterial, and fungal dynamics have been reported[11, 25, 26], but very little is known regarding the shift of soil net N transformation rates, N functional microbes, and underlying N transformation mechanisms This information can help achieve in-depth understanding N cycling process, reactive N availability and N2O emissions potential during ecological restoration, providing predictions and mitigation strategies for N2O emissions. The objective of this study was to: (1) evaluate net N transformation rates during the 40 years of forest ecosystem restoration after agricultural abandonment; (2) quantify the dynamic evolution of N microbial genes in the process of vegetation restoration; (3) determine quantitative relationships between net N transformation rates and N functional genes; and (4) discern key functional genes that govern net N transformation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
